Roll skia/third_party/skcms 14ea609fa6ca..99b01c076f47 (1 commits)

https://skia.googlesource.com/skcms.git/+log/14ea609fa6ca..99b01c076f47

2018-07-02 mtklein@chromium.org move skcms impl into skcms.c


The AutoRoll server is located here: https://skcms-skia-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
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CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
TBR=ethannicholas@google.com

Change-Id: I950f7b604eef056641fec3e6691d8c8a928d2d37
Reviewed-on: https://skia-review.googlesource.com/138950
Commit-Queue: skcms-skia-autoroll <skcms-skia-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Reviewed-by: skcms-skia-autoroll <skcms-skia-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>

9 files changed, 2322 insertions, 2395 deletions

diff --git a/third_party/skcms/skcms.c b/third_party/skcms/skcms.c
index 6b1abf59dd..5b66128ab0 100644
--- a/third_party/skcms/skcms.c
+++ b/third_party/skcms/skcms.c
@@ -5,11 +5,2323 @@
  * found in the LICENSE file.
  */
 
-// skcms.c is a unity build target for skcms, #including every other C source file.
-
-#include "src/Curve.c"
-#include "src/ICCProfile.c"
-#include "src/LinearAlgebra.c"
-#include "src/PortableMath.c"
-#include "src/TransferFunction.c"
-#include "src/Transform.c"
+#include "skcms.h"
+#include "skcms_internal.h"
+#include <assert.h>
+#include <float.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+static float minus_1_ulp(float x) {
+    int32_t bits;
+    memcpy(&bits, &x, sizeof(bits));
+    bits = bits - 1;
+    memcpy(&x, &bits, sizeof(bits));
+    return x;
+}
+
+float skcms_eval_curve(const skcms_Curve* curve, float x) {
+    if (curve->table_entries == 0) {
+        return skcms_TransferFunction_eval(&curve->parametric, x);
+    }
+
+    float ix = fmaxf_(0, fminf_(x, 1)) * (curve->table_entries - 1);
+    int   lo = (int)            ix,
+          hi = (int)minus_1_ulp(ix + 1.0f);
+    float t = ix - (float)lo;
+
+    float l, h;
+    if (curve->table_8) {
+        l = curve->table_8[lo] * (1/255.0f);
+        h = curve->table_8[hi] * (1/255.0f);
+    } else {
+        uint16_t be_l, be_h;
+        memcpy(&be_l, curve->table_16 + 2*lo, 2);
+        memcpy(&be_h, curve->table_16 + 2*hi, 2);
+        uint16_t le_l = ((be_l << 8) | (be_l >> 8)) & 0xffff;
+        uint16_t le_h = ((be_h << 8) | (be_h >> 8)) & 0xffff;
+        l = le_l * (1/65535.0f);
+        h = le_h * (1/65535.0f);
+    }
+    return l + (h-l)*t;
+}
+
+float skcms_MaxRoundtripError(const skcms_Curve* curve, const skcms_TransferFunction* inv_tf) {
+    uint32_t N = curve->table_entries > 256 ? curve->table_entries : 256;
+    const float dx = 1.0f / (N - 1);
+    float err = 0;
+    for (uint32_t i = 0; i < N; i++) {
+        float x = i * dx,
+              y = skcms_eval_curve(curve, x);
+        err = fmaxf_(err, fabsf_(x - skcms_TransferFunction_eval(inv_tf, y)));
+    }
+    return err;
+}
+
+bool skcms_AreApproximateInverses(const skcms_Curve* curve, const skcms_TransferFunction* inv_tf) {
+    return skcms_MaxRoundtripError(curve, inv_tf) < (1/512.0f);
+}
+
+// Additional ICC signature values that are only used internally
+enum {
+    // File signature
+    skcms_Signature_acsp = 0x61637370,
+
+    // Tag signatures
+    skcms_Signature_rTRC = 0x72545243,
+    skcms_Signature_gTRC = 0x67545243,
+    skcms_Signature_bTRC = 0x62545243,
+    skcms_Signature_kTRC = 0x6B545243,
+
+    skcms_Signature_rXYZ = 0x7258595A,
+    skcms_Signature_gXYZ = 0x6758595A,
+    skcms_Signature_bXYZ = 0x6258595A,
+
+    skcms_Signature_A2B0 = 0x41324230,
+    skcms_Signature_A2B1 = 0x41324231,
+    skcms_Signature_mAB  = 0x6D414220,
+
+    skcms_Signature_CHAD = 0x63686164,
+
+    // Type signatures
+    skcms_Signature_curv = 0x63757276,
+    skcms_Signature_mft1 = 0x6D667431,
+    skcms_Signature_mft2 = 0x6D667432,
+    skcms_Signature_para = 0x70617261,
+    skcms_Signature_sf32 = 0x73663332,
+    // XYZ is also a PCS signature, so it's defined in skcms.h
+    // skcms_Signature_XYZ = 0x58595A20,
+};
+
+static uint16_t read_big_u16(const uint8_t* ptr) {
+    uint16_t be;
+    memcpy(&be, ptr, sizeof(be));
+#if defined(_MSC_VER)
+    return _byteswap_ushort(be);
+#else
+    return __builtin_bswap16(be);
+#endif
+}
+
+static uint32_t read_big_u32(const uint8_t* ptr) {
+    uint32_t be;
+    memcpy(&be, ptr, sizeof(be));
+#if defined(_MSC_VER)
+    return _byteswap_ulong(be);
+#else
+    return __builtin_bswap32(be);
+#endif
+}
+
+static int32_t read_big_i32(const uint8_t* ptr) {
+    return (int32_t)read_big_u32(ptr);
+}
+
+static float read_big_fixed(const uint8_t* ptr) {
+    return read_big_i32(ptr) * (1.0f / 65536.0f);
+}
+
+// Maps to an in-memory profile so that fields line up to the locations specified
+// in ICC.1:2010, section 7.2
+typedef struct {
+    uint8_t size                [ 4];
+    uint8_t cmm_type            [ 4];
+    uint8_t version             [ 4];
+    uint8_t profile_class       [ 4];
+    uint8_t data_color_space    [ 4];
+    uint8_t pcs                 [ 4];
+    uint8_t creation_date_time  [12];
+    uint8_t signature           [ 4];
+    uint8_t platform            [ 4];
+    uint8_t flags               [ 4];
+    uint8_t device_manufacturer [ 4];
+    uint8_t device_model        [ 4];
+    uint8_t device_attributes   [ 8];
+    uint8_t rendering_intent    [ 4];
+    uint8_t illuminant_X        [ 4];
+    uint8_t illuminant_Y        [ 4];
+    uint8_t illuminant_Z        [ 4];
+    uint8_t creator             [ 4];
+    uint8_t profile_id          [16];
+    uint8_t reserved            [28];
+    uint8_t tag_count           [ 4]; // Technically not part of header, but required
+} header_Layout;
+
+typedef struct {
+    uint8_t signature [4];
+    uint8_t offset    [4];
+    uint8_t size      [4];
+} tag_Layout;
+
+static const tag_Layout* get_tag_table(const skcms_ICCProfile* profile) {
+    return (const tag_Layout*)(profile->buffer + SAFE_SIZEOF(header_Layout));
+}
+
+// s15Fixed16ArrayType is technically variable sized, holding N values. However, the only valid
+// use of the type is for the CHAD tag that stores exactly nine values.
+typedef struct {
+    uint8_t type     [ 4];
+    uint8_t reserved [ 4];
+    uint8_t values   [36];
+} sf32_Layout;
+
+bool skcms_GetCHAD(const skcms_ICCProfile* profile, skcms_Matrix3x3* m) {
+    skcms_ICCTag tag;
+    if (!skcms_GetTagBySignature(profile, skcms_Signature_CHAD, &tag)) {
+        return false;
+    }
+
+    if (tag.type != skcms_Signature_sf32 || tag.size < SAFE_SIZEOF(sf32_Layout)) {
+        return false;
+    }
+
+    const sf32_Layout* sf32Tag = (const sf32_Layout*)tag.buf;
+    const uint8_t* values = sf32Tag->values;
+    for (int r = 0; r < 3; ++r)
+    for (int c = 0; c < 3; ++c, values += 4) {
+        m->vals[r][c] = read_big_fixed(values);
+    }
+    return true;
+}
+
+// XYZType is technically variable sized, holding N XYZ triples. However, the only valid uses of
+// the type are for tags/data that store exactly one triple.
+typedef struct {
+    uint8_t type     [4];
+    uint8_t reserved [4];
+    uint8_t X        [4];
+    uint8_t Y        [4];
+    uint8_t Z        [4];
+} XYZ_Layout;
+
+static bool read_tag_xyz(const skcms_ICCTag* tag, float* x, float* y, float* z) {
+    if (tag->type != skcms_Signature_XYZ || tag->size < SAFE_SIZEOF(XYZ_Layout)) {
+        return false;
+    }
+
+    const XYZ_Layout* xyzTag = (const XYZ_Layout*)tag->buf;
+
+    *x = read_big_fixed(xyzTag->X);
+    *y = read_big_fixed(xyzTag->Y);
+    *z = read_big_fixed(xyzTag->Z);
+    return true;
+}
+
+static bool read_to_XYZD50(const skcms_ICCTag* rXYZ, const skcms_ICCTag* gXYZ,
+                           const skcms_ICCTag* bXYZ, skcms_Matrix3x3* toXYZ) {
+    return read_tag_xyz(rXYZ, &toXYZ->vals[0][0], &toXYZ->vals[1][0], &toXYZ->vals[2][0]) &&
+           read_tag_xyz(gXYZ, &toXYZ->vals[0][1], &toXYZ->vals[1][1], &toXYZ->vals[2][1]) &&
+           read_tag_xyz(bXYZ, &toXYZ->vals[0][2], &toXYZ->vals[1][2], &toXYZ->vals[2][2]);
+}
+
+typedef struct {
+    uint8_t type          [4];
+    uint8_t reserved_a    [4];
+    uint8_t function_type [2];
+    uint8_t reserved_b    [2];
+    uint8_t parameters    [ ];  // 1, 3, 4, 5, or 7 s15.16 parameters, depending on function_type
+} para_Layout;
+
+static bool read_curve_para(const uint8_t* buf, uint32_t size,
+                            skcms_Curve* curve, uint32_t* curve_size) {
+    if (size < SAFE_SIZEOF(para_Layout)) {
+        return false;
+    }
+
+    const para_Layout* paraTag = (const para_Layout*)buf;
+
+    enum { kG = 0, kGAB = 1, kGABC = 2, kGABCD = 3, kGABCDEF = 4 };
+    uint16_t function_type = read_big_u16(paraTag->function_type);
+    if (function_type > kGABCDEF) {
+        return false;
+    }
+
+    static const uint32_t curve_bytes[] = { 4, 12, 16, 20, 28 };
+    if (size < SAFE_SIZEOF(para_Layout) + curve_bytes[function_type]) {
+        return false;
+    }
+
+    if (curve_size) {
+        *curve_size = SAFE_SIZEOF(para_Layout) + curve_bytes[function_type];
+    }
+
+    curve->table_entries = 0;
+    curve->parametric.a  = 1.0f;
+    curve->parametric.b  = 0.0f;
+    curve->parametric.c  = 0.0f;
+    curve->parametric.d  = 0.0f;
+    curve->parametric.e  = 0.0f;
+    curve->parametric.f  = 0.0f;
+    curve->parametric.g  = read_big_fixed(paraTag->parameters);
+
+    switch (function_type) {
+        case kGAB:
+            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
+            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
+            if (curve->parametric.a == 0) {
+                return false;
+            }
+            curve->parametric.d = -curve->parametric.b / curve->parametric.a;
+            break;
+        case kGABC:
+            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
+            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
+            curve->parametric.e = read_big_fixed(paraTag->parameters + 12);
+            if (curve->parametric.a == 0) {
+                return false;
+            }
+            curve->parametric.d = -curve->parametric.b / curve->parametric.a;
+            curve->parametric.f = curve->parametric.e;
+            break;
+        case kGABCD:
+            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
+            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
+            curve->parametric.c = read_big_fixed(paraTag->parameters + 12);
+            curve->parametric.d = read_big_fixed(paraTag->parameters + 16);
+            break;
+        case kGABCDEF:
+            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
+            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
+            curve->parametric.c = read_big_fixed(paraTag->parameters + 12);
+            curve->parametric.d = read_big_fixed(paraTag->parameters + 16);
+            curve->parametric.e = read_big_fixed(paraTag->parameters + 20);
+            curve->parametric.f = read_big_fixed(paraTag->parameters + 24);
+            break;
+    }
+    return skcms_TransferFunction_isValid(&curve->parametric);
+}
+
+typedef struct {
+    uint8_t type          [4];
+    uint8_t reserved      [4];
+    uint8_t value_count   [4];
+    uint8_t parameters    [ ];  // value_count parameters (8.8 if 1, uint16 (n*65535) if > 1)
+} curv_Layout;
+
+static bool read_curve_curv(const uint8_t* buf, uint32_t size,
+                            skcms_Curve* curve, uint32_t* curve_size) {
+    if (size < SAFE_SIZEOF(curv_Layout)) {
+        return false;
+    }
+
+    const curv_Layout* curvTag = (const curv_Layout*)buf;
+
+    uint32_t value_count = read_big_u32(curvTag->value_count);
+    if (size < SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t)) {
+        return false;
+    }
+
+    if (curve_size) {
+        *curve_size = SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t);
+    }
+
+    if (value_count < 2) {
+        curve->table_entries = 0;
+        curve->parametric.a  = 1.0f;
+        curve->parametric.b  = 0.0f;
+        curve->parametric.c  = 0.0f;
+        curve->parametric.d  = 0.0f;
+        curve->parametric.e  = 0.0f;
+        curve->parametric.f  = 0.0f;
+        if (value_count == 0) {
+            // Empty tables are a shorthand for an identity curve
+            curve->parametric.g = 1.0f;
+        } else {
+            // Single entry tables are a shorthand for simple gamma
+            curve->parametric.g = read_big_u16(curvTag->parameters) * (1.0f / 256.0f);
+        }
+    } else {
+        curve->table_8       = NULL;
+        curve->table_16      = curvTag->parameters;
+        curve->table_entries = value_count;
+    }
+
+    return true;
+}
+
+// Parses both curveType and parametricCurveType data. Ensures that at most 'size' bytes are read.
+// If curve_size is not NULL, writes the number of bytes used by the curve in (*curve_size).
+static bool read_curve(const uint8_t* buf, uint32_t size,
+                       skcms_Curve* curve, uint32_t* curve_size) {
+    if (!buf || size < 4 || !curve) {
+        return false;
+    }
+
+    uint32_t type = read_big_u32(buf);
+    if (type == skcms_Signature_para) {
+        return read_curve_para(buf, size, curve, curve_size);
+    } else if (type == skcms_Signature_curv) {
+        return read_curve_curv(buf, size, curve, curve_size);
+    }
+
+    return false;
+}
+
+// mft1 and mft2 share a large chunk of data
+typedef struct {
+    uint8_t type                 [ 4];
+    uint8_t reserved_a           [ 4];
+    uint8_t input_channels       [ 1];
+    uint8_t output_channels      [ 1];
+    uint8_t grid_points          [ 1];
+    uint8_t reserved_b           [ 1];
+    uint8_t matrix               [36];
+} mft_CommonLayout;
+
+typedef struct {
+    mft_CommonLayout common      [ 1];
+
+    uint8_t tables               [  ];
+} mft1_Layout;
+
+typedef struct {
+    mft_CommonLayout common      [ 1];
+
+    uint8_t input_table_entries  [ 2];
+    uint8_t output_table_entries [ 2];
+    uint8_t tables               [  ];
+} mft2_Layout;
+
+static bool read_mft_common(const mft_CommonLayout* mftTag, skcms_A2B* a2b) {
+    // MFT matrices are applied before the first set of curves, but must be identity unless the
+    // input is PCSXYZ. We don't support PCSXYZ profiles, so we ignore this matrix. Note that the
+    // matrix in skcms_A2B is applied later in the pipe, so supporting this would require another
+    // field/flag.
+    a2b->matrix_channels = 0;
+
+    a2b->input_channels  = mftTag->input_channels[0];
+    a2b->output_channels = mftTag->output_channels[0];
+
+    // We require exactly three (ie XYZ/Lab/RGB) output channels
+    if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) {
+        return false;
+    }
+    // We require at least one, and no more than four (ie CMYK) input channels
+    if (a2b->input_channels < 1 || a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) {
+        return false;
+    }
+
+    for (uint32_t i = 0; i < a2b->input_channels; ++i) {
+        a2b->grid_points[i] = mftTag->grid_points[0];
+    }
+    // The grid only makes sense with at least two points along each axis
+    if (a2b->grid_points[0] < 2) {
+        return false;
+    }
+
+    return true;
+}
+
+static bool init_a2b_tables(const uint8_t* table_base, uint64_t max_tables_len, uint32_t byte_width,
+                            uint32_t input_table_entries, uint32_t output_table_entries,
+                            skcms_A2B* a2b) {
+    // byte_width is 1 or 2, [input|output]_table_entries are in [2, 4096], so no overflow
+    uint32_t byte_len_per_input_table  = input_table_entries * byte_width;
+    uint32_t byte_len_per_output_table = output_table_entries * byte_width;
+
+    // [input|output]_channels are <= 4, so still no overflow
+    uint32_t byte_len_all_input_tables  = a2b->input_channels * byte_len_per_input_table;
+    uint32_t byte_len_all_output_tables = a2b->output_channels * byte_len_per_output_table;
+
+    uint64_t grid_size = a2b->output_channels * byte_width;
+    for (uint32_t axis = 0; axis < a2b->input_channels; ++axis) {
+        grid_size *= a2b->grid_points[axis];
+    }
+
+    if (max_tables_len < byte_len_all_input_tables + grid_size + byte_len_all_output_tables) {
+        return false;
+    }
+
+    for (uint32_t i = 0; i < a2b->input_channels; ++i) {
+        a2b->input_curves[i].table_entries = input_table_entries;
+        if (byte_width == 1) {
+            a2b->input_curves[i].table_8  = table_base + i * byte_len_per_input_table;
+            a2b->input_curves[i].table_16 = NULL;
+        } else {
+            a2b->input_curves[i].table_8  = NULL;
+            a2b->input_curves[i].table_16 = table_base + i * byte_len_per_input_table;
+        }
+    }
+
+    if (byte_width == 1) {
+        a2b->grid_8  = table_base + byte_len_all_input_tables;
+        a2b->grid_16 = NULL;
+    } else {
+        a2b->grid_8  = NULL;
+        a2b->grid_16 = table_base + byte_len_all_input_tables;
+    }
+
+    const uint8_t* output_table_base = table_base + byte_len_all_input_tables + grid_size;
+    for (uint32_t i = 0; i < a2b->output_channels; ++i) {
+        a2b->output_curves[i].table_entries = output_table_entries;
+        if (byte_width == 1) {
+            a2b->output_curves[i].table_8  = output_table_base + i * byte_len_per_output_table;
+            a2b->output_curves[i].table_16 = NULL;
+        } else {
+            a2b->output_curves[i].table_8  = NULL;
+            a2b->output_curves[i].table_16 = output_table_base + i * byte_len_per_output_table;
+        }
+    }
+
+    return true;
+}
+
+static bool read_tag_mft1(const skcms_ICCTag* tag, skcms_A2B* a2b) {
+    if (tag->size < SAFE_SIZEOF(mft1_Layout)) {
+        return false;
+    }
+
+    const mft1_Layout* mftTag = (const mft1_Layout*)tag->buf;
+    if (!read_mft_common(mftTag->common, a2b)) {
+        return false;
+    }
+
+    uint32_t input_table_entries  = 256;
+    uint32_t output_table_entries = 256;
+
+    return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft1_Layout), 1,
+                           input_table_entries, output_table_entries, a2b);
+}
+
+static bool read_tag_mft2(const skcms_ICCTag* tag, skcms_A2B* a2b) {
+    if (tag->size < SAFE_SIZEOF(mft2_Layout)) {
+        return false;
+    }
+
+    const mft2_Layout* mftTag = (const mft2_Layout*)tag->buf;
+    if (!read_mft_common(mftTag->common, a2b)) {
+        return false;
+    }
+
+    uint32_t input_table_entries = read_big_u16(mftTag->input_table_entries);
+    uint32_t output_table_entries = read_big_u16(mftTag->output_table_entries);
+
+    // ICC spec mandates that 2 <= table_entries <= 4096
+    if (input_table_entries < 2 || input_table_entries > 4096 ||
+        output_table_entries < 2 || output_table_entries > 4096) {
+        return false;
+    }
+
+    return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft2_Layout), 2,
+                           input_table_entries, output_table_entries, a2b);
+}
+
+static bool read_curves(const uint8_t* buf, uint32_t size, uint32_t curve_offset,
+                        uint32_t num_curves, skcms_Curve* curves) {
+    for (uint32_t i = 0; i < num_curves; ++i) {
+        if (curve_offset > size) {
+            return false;
+        }
+
+        uint32_t curve_bytes;
+        if (!read_curve(buf + curve_offset, size - curve_offset, &curves[i], &curve_bytes)) {
+            return false;
+        }
+
+        if (curve_bytes > UINT32_MAX - 3) {
+            return false;
+        }
+        curve_bytes = (curve_bytes + 3) & ~3U;
+
+        uint64_t new_offset_64 = (uint64_t)curve_offset + curve_bytes;
+        curve_offset = (uint32_t)new_offset_64;
+        if (new_offset_64 != curve_offset) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+typedef struct {
+    uint8_t type                 [ 4];
+    uint8_t reserved_a           [ 4];
+    uint8_t input_channels       [ 1];
+    uint8_t output_channels      [ 1];
+    uint8_t reserved_b           [ 2];
+    uint8_t b_curve_offset       [ 4];
+    uint8_t matrix_offset        [ 4];
+    uint8_t m_curve_offset       [ 4];
+    uint8_t clut_offset          [ 4];
+    uint8_t a_curve_offset       [ 4];
+} mAB_Layout;
+
+typedef struct {
+    uint8_t grid_points          [16];
+    uint8_t grid_byte_width      [ 1];
+    uint8_t reserved             [ 3];
+    uint8_t data                 [  ];
+} mABCLUT_Layout;
+
+static bool read_tag_mab(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) {
+    if (tag->size < SAFE_SIZEOF(mAB_Layout)) {
+        return false;
+    }
+
+    const mAB_Layout* mABTag = (const mAB_Layout*)tag->buf;
+
+    a2b->input_channels  = mABTag->input_channels[0];
+    a2b->output_channels = mABTag->output_channels[0];
+
+    // We require exactly three (ie XYZ/Lab/RGB) output channels
+    if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) {
+        return false;
+    }
+    // We require no more than four (ie CMYK) input channels
+    if (a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) {
+        return false;
+    }
+
+    uint32_t b_curve_offset = read_big_u32(mABTag->b_curve_offset);
+    uint32_t matrix_offset  = read_big_u32(mABTag->matrix_offset);
+    uint32_t m_curve_offset = read_big_u32(mABTag->m_curve_offset);
+    uint32_t clut_offset    = read_big_u32(mABTag->clut_offset);
+    uint32_t a_curve_offset = read_big_u32(mABTag->a_curve_offset);
+
+    // "B" curves must be present
+    if (0 == b_curve_offset) {
+        return false;
+    }
+
+    if (!read_curves(tag->buf, tag->size, b_curve_offset, a2b->output_channels,
+                     a2b->output_curves)) {
+        return false;
+    }
+
+    // "M" curves and Matrix must be used together
+    if (0 != m_curve_offset) {
+        if (0 == matrix_offset) {
+            return false;
+        }
+        a2b->matrix_channels = a2b->output_channels;
+        if (!read_curves(tag->buf, tag->size, m_curve_offset, a2b->matrix_channels,
+                         a2b->matrix_curves)) {
+            return false;
+        }
+
+        // Read matrix, which is stored as a row-major 3x3, followed by the fourth column
+        if (tag->size < matrix_offset + 12 * SAFE_SIZEOF(uint32_t)) {
+            return false;
+        }
+        float encoding_factor = pcs_is_xyz ? 65535 / 32768.0f : 1.0f;
+        const uint8_t* mtx_buf = tag->buf + matrix_offset;
+        a2b->matrix.vals[0][0] = encoding_factor * read_big_fixed(mtx_buf + 0);
+        a2b->matrix.vals[0][1] = encoding_factor * read_big_fixed(mtx_buf + 4);
+        a2b->matrix.vals[0][2] = encoding_factor * read_big_fixed(mtx_buf + 8);
+        a2b->matrix.vals[1][0] = encoding_factor * read_big_fixed(mtx_buf + 12);
+        a2b->matrix.vals[1][1] = encoding_factor * read_big_fixed(mtx_buf + 16);
+        a2b->matrix.vals[1][2] = encoding_factor * read_big_fixed(mtx_buf + 20);
+        a2b->matrix.vals[2][0] = encoding_factor * read_big_fixed(mtx_buf + 24);
+        a2b->matrix.vals[2][1] = encoding_factor * read_big_fixed(mtx_buf + 28);
+        a2b->matrix.vals[2][2] = encoding_factor * read_big_fixed(mtx_buf + 32);
+        a2b->matrix.vals[0][3] = encoding_factor * read_big_fixed(mtx_buf + 36);
+        a2b->matrix.vals[1][3] = encoding_factor * read_big_fixed(mtx_buf + 40);
+        a2b->matrix.vals[2][3] = encoding_factor * read_big_fixed(mtx_buf + 44);
+    } else {
+        if (0 != matrix_offset) {
+            return false;
+        }
+        a2b->matrix_channels = 0;
+    }
+
+    // "A" curves and CLUT must be used together
+    if (0 != a_curve_offset) {
+        if (0 == clut_offset) {
+            return false;
+        }
+        if (!read_curves(tag->buf, tag->size, a_curve_offset, a2b->input_channels,
+                         a2b->input_curves)) {
+            return false;
+        }
+
+        if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout)) {
+            return false;
+        }
+        const mABCLUT_Layout* clut = (const mABCLUT_Layout*)(tag->buf + clut_offset);
+
+        if (clut->grid_byte_width[0] == 1) {
+            a2b->grid_8  = clut->data;
+            a2b->grid_16 = NULL;
+        } else if (clut->grid_byte_width[0] == 2) {
+            a2b->grid_8  = NULL;
+            a2b->grid_16 = clut->data;
+        } else {
+            return false;
+        }
+
+        uint64_t grid_size = a2b->output_channels * clut->grid_byte_width[0];
+        for (uint32_t i = 0; i < a2b->input_channels; ++i) {
+            a2b->grid_points[i] = clut->grid_points[i];
+            // The grid only makes sense with at least two points along each axis
+            if (a2b->grid_points[i] < 2) {
+                return false;
+            }
+            grid_size *= a2b->grid_points[i];
+        }
+        if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout) + grid_size) {
+            return false;
+        }
+    } else {
+        if (0 != clut_offset) {
+            return false;
+        }
+
+        // If there is no CLUT, the number of input and output channels must match
+        if (a2b->input_channels != a2b->output_channels) {
+            return false;
+        }
+
+        // Zero out the number of input channels to signal that we're skipping this stage
+        a2b->input_channels = 0;
+    }
+
+    return true;
+}
+
+static bool read_a2b(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) {
+    bool ok = false;
+    if (tag->type == skcms_Signature_mft1) {
+        ok = read_tag_mft1(tag, a2b);
+    } else if (tag->type == skcms_Signature_mft2) {
+        ok = read_tag_mft2(tag, a2b);
+    } else if (tag->type == skcms_Signature_mAB) {
+        ok = read_tag_mab(tag, a2b, pcs_is_xyz);
+    }
+    if (!ok) {
+        return false;
+    }
+
+    // Detect and canonicalize identity tables.
+    skcms_Curve* curves[] = {
+        a2b->input_channels  > 0 ? a2b->input_curves  + 0 : NULL,
+        a2b->input_channels  > 1 ? a2b->input_curves  + 1 : NULL,
+        a2b->input_channels  > 2 ? a2b->input_curves  + 2 : NULL,
+        a2b->input_channels  > 3 ? a2b->input_curves  + 3 : NULL,
+        a2b->matrix_channels > 0 ? a2b->matrix_curves + 0 : NULL,
+        a2b->matrix_channels > 1 ? a2b->matrix_curves + 1 : NULL,
+        a2b->matrix_channels > 2 ? a2b->matrix_curves + 2 : NULL,
+        a2b->output_channels > 0 ? a2b->output_curves + 0 : NULL,
+        a2b->output_channels > 1 ? a2b->output_curves + 1 : NULL,
+        a2b->output_channels > 2 ? a2b->output_curves + 2 : NULL,
+    };
+
+    for (int i = 0; i < ARRAY_COUNT(curves); i++) {
+        skcms_Curve* curve = curves[i];
+
+        if (curve && curve->table_entries && curve->table_entries <= (uint32_t)INT_MAX) {
+            int N = (int)curve->table_entries;
+
+            float c,d,f;
+            if (N == skcms_fit_linear(curve, N, 1.0f/(2*N), &c,&d,&f)
+                && c == 1.0f
+                && f == 0.0f) {
+                curve->table_entries = 0;
+                curve->table_8       = NULL;
+                curve->table_16      = NULL;
+                curve->parametric    = (skcms_TransferFunction){1,1,0,0,0,0,0};
+            }
+        }
+    }
+
+    return true;
+}
+
+void skcms_GetTagByIndex(const skcms_ICCProfile* profile, uint32_t idx, skcms_ICCTag* tag) {
+    if (!profile || !profile->buffer || !tag) { return; }
+    if (idx > profile->tag_count) { return; }
+    const tag_Layout* tags = get_tag_table(profile);
+    tag->signature = read_big_u32(tags[idx].signature);
+    tag->size      = read_big_u32(tags[idx].size);
+    tag->buf       = read_big_u32(tags[idx].offset) + profile->buffer;
+    tag->type      = read_big_u32(tag->buf);
+}
+
+bool skcms_GetTagBySignature(const skcms_ICCProfile* profile, uint32_t sig, skcms_ICCTag* tag) {
+    if (!profile || !profile->buffer || !tag) { return false; }
+    const tag_Layout* tags = get_tag_table(profile);
+    for (uint32_t i = 0; i < profile->tag_count; ++i) {
+        if (read_big_u32(tags[i].signature) == sig) {
+            tag->signature = sig;
+            tag->size      = read_big_u32(tags[i].size);
+            tag->buf       = read_big_u32(tags[i].offset) + profile->buffer;
+            tag->type      = read_big_u32(tag->buf);
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool usable_as_src(const skcms_ICCProfile* profile) {
+    return profile->has_A2B
+       || (profile->has_trc && profile->has_toXYZD50);
+}
+
+bool skcms_Parse(const void* buf, size_t len, skcms_ICCProfile* profile) {
+    assert(SAFE_SIZEOF(header_Layout) == 132);
+
+    if (!profile) {
+        return false;
+    }
+    memset(profile, 0, SAFE_SIZEOF(*profile));
+
+    if (len < SAFE_SIZEOF(header_Layout)) {
+        return false;
+    }
+
+    // Byte-swap all header fields
+    const header_Layout* header = buf;
+    profile->buffer              = buf;
+    profile->size                = read_big_u32(header->size);
+    uint32_t version             = read_big_u32(header->version);
+    profile->data_color_space    = read_big_u32(header->data_color_space);
+    profile->pcs                 = read_big_u32(header->pcs);
+    uint32_t signature           = read_big_u32(header->signature);
+    float illuminant_X           = read_big_fixed(header->illuminant_X);
+    float illuminant_Y           = read_big_fixed(header->illuminant_Y);
+    float illuminant_Z           = read_big_fixed(header->illuminant_Z);
+    profile->tag_count           = read_big_u32(header->tag_count);
+
+    // Validate signature, size (smaller than buffer, large enough to hold tag table),
+    // and major version
+    uint64_t tag_table_size = profile->tag_count * SAFE_SIZEOF(tag_Layout);
+    if (signature != skcms_Signature_acsp ||
+        profile->size > len ||
+        profile->size < SAFE_SIZEOF(header_Layout) + tag_table_size ||
+        (version >> 24) > 4) {
+        return false;
+    }
+
+    // Validate that illuminant is D50 white
+    if (fabsf_(illuminant_X - 0.9642f) > 0.0100f ||
+        fabsf_(illuminant_Y - 1.0000f) > 0.0100f ||
+        fabsf_(illuminant_Z - 0.8249f) > 0.0100f) {
+        return false;
+    }
+
+    // Validate that all tag entries have sane offset + size
+    const tag_Layout* tags = get_tag_table(profile);
+    for (uint32_t i = 0; i < profile->tag_count; ++i) {
+        uint32_t tag_offset = read_big_u32(tags[i].offset);
+        uint32_t tag_size   = read_big_u32(tags[i].size);
+        uint64_t tag_end    = (uint64_t)tag_offset + (uint64_t)tag_size;
+        if (tag_size < 4 || tag_end > profile->size) {
+            return false;
+        }
+    }
+
+    if (profile->pcs != skcms_Signature_XYZ && profile->pcs != skcms_Signature_Lab) {
+        return false;
+    }
+
+    bool pcs_is_xyz = profile->pcs == skcms_Signature_XYZ;
+
+    // Pre-parse commonly used tags.
+    skcms_ICCTag kTRC;
+    if (profile->data_color_space == skcms_Signature_Gray &&
+        skcms_GetTagBySignature(profile, skcms_Signature_kTRC, &kTRC)) {
+        if (!read_curve(kTRC.buf, kTRC.size, &profile->trc[0], NULL)) {
+            // Malformed tag
+            return false;
+        }
+        profile->trc[1] = profile->trc[0];
+        profile->trc[2] = profile->trc[0];
+        profile->has_trc = true;
+
+        if (pcs_is_xyz) {
+            profile->toXYZD50.vals[0][0] = illuminant_X;
+            profile->toXYZD50.vals[1][1] = illuminant_Y;
+            profile->toXYZD50.vals[2][2] = illuminant_Z;
+            profile->has_toXYZD50 = true;
+        }
+    } else {
+        skcms_ICCTag rTRC, gTRC, bTRC;
+        if (skcms_GetTagBySignature(profile, skcms_Signature_rTRC, &rTRC) &&
+            skcms_GetTagBySignature(profile, skcms_Signature_gTRC, &gTRC) &&
+            skcms_GetTagBySignature(profile, skcms_Signature_bTRC, &bTRC)) {
+            if (!read_curve(rTRC.buf, rTRC.size, &profile->trc[0], NULL) ||
+                !read_curve(gTRC.buf, gTRC.size, &profile->trc[1], NULL) ||
+                !read_curve(bTRC.buf, bTRC.size, &profile->trc[2], NULL)) {
+                // Malformed TRC tags
+                return false;
+            }
+            profile->has_trc = true;
+        }
+
+        skcms_ICCTag rXYZ, gXYZ, bXYZ;
+        if (skcms_GetTagBySignature(profile, skcms_Signature_rXYZ, &rXYZ) &&
+            skcms_GetTagBySignature(profile, skcms_Signature_gXYZ, &gXYZ) &&
+            skcms_GetTagBySignature(profile, skcms_Signature_bXYZ, &bXYZ)) {
+            if (!read_to_XYZD50(&rXYZ, &gXYZ, &bXYZ, &profile->toXYZD50)) {
+                // Malformed XYZ tags
+                return false;
+            }
+            profile->has_toXYZD50 = true;
+        }
+    }
+
+    skcms_ICCTag a2b_tag;
+
+    // For now, we're preferring A2B0, like Skia does and the ICC spec tells us to.
+    // TODO: prefer A2B1 (relative colormetric) over A2B0 (perceptual)?
+    // This breaks with the ICC spec, but we think it's a good idea, given that TRC curves
+    // and all our known users are thinking exclusively in terms of relative colormetric.
+    const uint32_t sigs[] = { skcms_Signature_A2B0, skcms_Signature_A2B1 };
+    for (int i = 0; i < ARRAY_COUNT(sigs); i++) {
+        if (skcms_GetTagBySignature(profile, sigs[i], &a2b_tag)) {
+            if (!read_a2b(&a2b_tag, &profile->A2B, pcs_is_xyz)) {
+                // Malformed A2B tag
+                return false;
+            }
+            profile->has_A2B = true;
+            break;
+        }
+    }
+
+    return usable_as_src(profile);
+}
+
+
+const skcms_ICCProfile* skcms_sRGB_profile() {
+    static const skcms_ICCProfile sRGB_profile = {
+        // These fields are moot when not a skcms_Parse()'d profile.
+        .buffer    = NULL,
+        .size      =    0,
+        .tag_count =    0,
+
+        // We choose to represent sRGB with its canonical transfer function,
+        // and with its canonical XYZD50 gamut matrix.
+        .data_color_space = skcms_Signature_RGB,
+        .pcs              = skcms_Signature_XYZ,
+        .has_trc      = true,
+        .has_toXYZD50 = true,
+        .has_A2B      = false,
+
+        .trc = {
+            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
+            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
+            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
+        },
+
+        .toXYZD50 = {{
+            { 0.436065674f, 0.385147095f, 0.143066406f },
+            { 0.222488403f, 0.716873169f, 0.060607910f },
+            { 0.013916016f, 0.097076416f, 0.714096069f },
+        }},
+    };
+    return &sRGB_profile;
+}
+
+const skcms_ICCProfile* skcms_XYZD50_profile() {
+    static const skcms_ICCProfile XYZD50_profile = {
+        .buffer           = NULL,
+        .size             = 0,
+        .tag_count        = 0,
+
+        .data_color_space = skcms_Signature_RGB,
+        .pcs              = skcms_Signature_XYZ,
+        .has_trc          = true,
+        .has_toXYZD50     = true,
+        .has_A2B          = false,
+
+        .trc = {
+            {{0, {1,1,0,0,0,0,0}}},
+            {{0, {1,1,0,0,0,0,0}}},
+            {{0, {1,1,0,0,0,0,0}}},
+        },
+
+        .toXYZD50 = {{
+            {1,0,0},
+            {0,1,0},
+            {0,0,1},
+        }},
+    };
+
+    return &XYZD50_profile;
+}
+
+const skcms_TransferFunction* skcms_sRGB_TransferFunction() {
+    return &skcms_sRGB_profile()->trc[0].parametric;
+}
+
+const skcms_TransferFunction* skcms_sRGB_Inverse_TransferFunction() {
+    static const skcms_TransferFunction sRGB_inv =
+        { (float)(1/2.4), 1.137119f, 0, 12.92f, 0.0031308f, -0.055f, 0 };
+    return &sRGB_inv;
+}
+
+const skcms_TransferFunction* skcms_Identity_TransferFunction() {
+    static const skcms_TransferFunction identity = {1,1,0,0,0,0,0};
+    return &identity;
+}
+
+const uint8_t skcms_252_random_bytes[] = {
+    8, 179, 128, 204, 253, 38, 134, 184, 68, 102, 32, 138, 99, 39, 169, 215,
+    119, 26, 3, 223, 95, 239, 52, 132, 114, 74, 81, 234, 97, 116, 244, 205, 30,
+    154, 173, 12, 51, 159, 122, 153, 61, 226, 236, 178, 229, 55, 181, 220, 191,
+    194, 160, 126, 168, 82, 131, 18, 180, 245, 163, 22, 246, 69, 235, 252, 57,
+    108, 14, 6, 152, 240, 255, 171, 242, 20, 227, 177, 238, 96, 85, 16, 211,
+    70, 200, 149, 155, 146, 127, 145, 100, 151, 109, 19, 165, 208, 195, 164,
+    137, 254, 182, 248, 64, 201, 45, 209, 5, 147, 207, 210, 113, 162, 83, 225,
+    9, 31, 15, 231, 115, 37, 58, 53, 24, 49, 197, 56, 120, 172, 48, 21, 214,
+    129, 111, 11, 50, 187, 196, 34, 60, 103, 71, 144, 47, 203, 77, 80, 232,
+    140, 222, 250, 206, 166, 247, 139, 249, 221, 72, 106, 27, 199, 117, 54,
+    219, 135, 118, 40, 79, 41, 251, 46, 93, 212, 92, 233, 148, 28, 121, 63,
+    123, 158, 105, 59, 29, 42, 143, 23, 0, 107, 176, 87, 104, 183, 156, 193,
+    189, 90, 188, 65, 190, 17, 198, 7, 186, 161, 1, 124, 78, 125, 170, 133,
+    174, 218, 67, 157, 75, 101, 89, 217, 62, 33, 141, 228, 25, 35, 91, 230, 4,
+    2, 13, 73, 86, 167, 237, 84, 243, 44, 185, 66, 130, 110, 150, 142, 216, 88,
+    112, 36, 224, 136, 202, 76, 94, 98, 175, 213
+};
+
+bool skcms_ApproximatelyEqualProfiles(const skcms_ICCProfile* A, const skcms_ICCProfile* B) {
+    // For now this is the essentially the same strategy we use in test_only.c
+    // for our skcms_Transform() smoke tests:
+    //    1) transform A to XYZD50
+    //    2) transform B to XYZD50
+    //    3) return true if they're similar enough
+    // Our current criterion in 3) is maximum 1 bit error per XYZD50 byte.
+
+    // Here are 252 of a random shuffle of all possible bytes.
+    // 252 is evenly divisible by 3 and 4.  Only 192, 10, 241, and 43 are missing.
+
+    if (A->data_color_space != B->data_color_space) {
+        return false;
+    }
+
+    // Interpret as RGB_888 if data color space is RGB or GRAY, RGBA_8888 if CMYK.
+    skcms_PixelFormat fmt = skcms_PixelFormat_RGB_888;
+    size_t npixels = 84;
+    if (A->data_color_space == skcms_Signature_CMYK) {
+        fmt = skcms_PixelFormat_RGBA_8888;
+        npixels = 63;
+    }
+
+    uint8_t dstA[252],
+            dstB[252];
+    if (!skcms_Transform(
+                skcms_252_random_bytes,     fmt, skcms_AlphaFormat_Unpremul, A,
+                dstA, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(),
+                npixels)) {
+        return false;
+    }
+    if (!skcms_Transform(
+                skcms_252_random_bytes,     fmt, skcms_AlphaFormat_Unpremul, B,
+                dstB, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(),
+                npixels)) {
+        return false;
+    }
+
+    for (size_t i = 0; i < 252; i++) {
+        if (abs((int)dstA[i] - (int)dstB[i]) > 1) {
+            return false;
+        }
+    }
+    return true;
+}
+
+bool skcms_TRCs_AreApproximateInverse(const skcms_ICCProfile* profile,
+                                      const skcms_TransferFunction* inv_tf) {
+    if (!profile || !profile->has_trc) {
+        return false;
+    }
+
+    return skcms_AreApproximateInverses(&profile->trc[0], inv_tf) &&
+           skcms_AreApproximateInverses(&profile->trc[1], inv_tf) &&
+           skcms_AreApproximateInverses(&profile->trc[2], inv_tf);
+}
+
+static bool is_zero_to_one(float x) {
+    return 0 <= x && x <= 1;
+}
+
+bool skcms_PrimariesToXYZD50(float rx, float ry,
+                             float gx, float gy,
+                             float bx, float by,
+                             float wx, float wy,
+                             skcms_Matrix3x3* toXYZD50) {
+    if (!is_zero_to_one(rx) || !is_zero_to_one(ry) ||
+        !is_zero_to_one(gx) || !is_zero_to_one(gy) ||
+        !is_zero_to_one(bx) || !is_zero_to_one(by) ||
+        !is_zero_to_one(wx) || !is_zero_to_one(wy) ||
+        !toXYZD50) {
+        return false;
+    }
+
+    // First, we need to convert xy values (primaries) to XYZ.
+    skcms_Matrix3x3 primaries = {{
+        { rx, gx, bx },
+        { ry, gy, by },
+        { 1 - rx - ry, 1 - gx - gy, 1 - bx - by },
+    }};
+    skcms_Matrix3x3 primaries_inv;
+    if (!skcms_Matrix3x3_invert(&primaries, &primaries_inv)) {
+        return false;
+    }
+
+    // Assumes that Y is 1.0f.
+    skcms_Vector3 wXYZ = { { wx / wy, 1, (1 - wx - wy) / wy } };
+    skcms_Vector3 XYZ = skcms_MV_mul(&primaries_inv, &wXYZ);
+
+    skcms_Matrix3x3 toXYZ = {{
+        { XYZ.vals[0],           0,           0 },
+        {           0, XYZ.vals[1],           0 },
+        {           0,           0, XYZ.vals[2] },
+    }};
+    toXYZ = skcms_Matrix3x3_concat(&primaries, &toXYZ);
+
+    // Now convert toXYZ matrix to toXYZD50.
+    skcms_Vector3 wXYZD50 = { { 0.96422f, 1.0f, 0.82521f } };
+
+    // Calculate the chromatic adaptation matrix.  We will use the Bradford method, thus
+    // the matrices below.  The Bradford method is used by Adobe and is widely considered
+    // to be the best.
+    skcms_Matrix3x3 xyz_to_lms = {{
+        {  0.8951f,  0.2664f, -0.1614f },
+        { -0.7502f,  1.7135f,  0.0367f },
+        {  0.0389f, -0.0685f,  1.0296f },
+    }};
+    skcms_Matrix3x3 lms_to_xyz = {{
+        {  0.9869929f, -0.1470543f, 0.1599627f },
+        {  0.4323053f,  0.5183603f, 0.0492912f },
+        { -0.0085287f,  0.0400428f, 0.9684867f },
+    }};
+
+    skcms_Vector3 srcCone = skcms_MV_mul(&xyz_to_lms, &wXYZ);
+    skcms_Vector3 dstCone = skcms_MV_mul(&xyz_to_lms, &wXYZD50);
+
+    skcms_Matrix3x3 DXtoD50 = {{
+        { dstCone.vals[0] / srcCone.vals[0], 0, 0 },
+        { 0, dstCone.vals[1] / srcCone.vals[1], 0 },
+        { 0, 0, dstCone.vals[2] / srcCone.vals[2] },
+    }};
+    DXtoD50 = skcms_Matrix3x3_concat(&DXtoD50, &xyz_to_lms);
+    DXtoD50 = skcms_Matrix3x3_concat(&lms_to_xyz, &DXtoD50);
+
+    *toXYZD50 = skcms_Matrix3x3_concat(&DXtoD50, &toXYZ);
+    return true;
+}
+
+
+bool skcms_Matrix3x3_invert(const skcms_Matrix3x3* src, skcms_Matrix3x3* dst) {
+    double a00 = src->vals[0][0],
+           a01 = src->vals[1][0],
+           a02 = src->vals[2][0],
+           a10 = src->vals[0][1],
+           a11 = src->vals[1][1],
+           a12 = src->vals[2][1],
+           a20 = src->vals[0][2],
+           a21 = src->vals[1][2],
+           a22 = src->vals[2][2];
+
+    double b0 = a00*a11 - a01*a10,
+           b1 = a00*a12 - a02*a10,
+           b2 = a01*a12 - a02*a11,
+           b3 = a20,
+           b4 = a21,
+           b5 = a22;
+
+    double determinant = b0*b5
+                       - b1*b4
+                       + b2*b3;
+
+    if (determinant == 0) {
+        return false;
+    }
+
+    double invdet = 1.0 / determinant;
+    if (invdet > +FLT_MAX || invdet < -FLT_MAX || !isfinitef_((float)invdet)) {
+        return false;
+    }
+
+    b0 *= invdet;
+    b1 *= invdet;
+    b2 *= invdet;
+    b3 *= invdet;
+    b4 *= invdet;
+    b5 *= invdet;
+
+    dst->vals[0][0] = (float)( a11*b5 - a12*b4 );
+    dst->vals[1][0] = (float)( a02*b4 - a01*b5 );
+    dst->vals[2][0] = (float)(        +     b2 );
+    dst->vals[0][1] = (float)( a12*b3 - a10*b5 );
+    dst->vals[1][1] = (float)( a00*b5 - a02*b3 );
+    dst->vals[2][1] = (float)(        -     b1 );
+    dst->vals[0][2] = (float)( a10*b4 - a11*b3 );
+    dst->vals[1][2] = (float)( a01*b3 - a00*b4 );
+    dst->vals[2][2] = (float)(        +     b0 );
+
+    for (int r = 0; r < 3; ++r)
+    for (int c = 0; c < 3; ++c) {
+        if (!isfinitef_(dst->vals[r][c])) {
+            return false;
+        }
+    }
+    return true;
+}
+
+skcms_Matrix3x3 skcms_Matrix3x3_concat(const skcms_Matrix3x3* A, const skcms_Matrix3x3* B) {
+    skcms_Matrix3x3 m = { { { 0,0,0 },{ 0,0,0 },{ 0,0,0 } } };
+    for (int r = 0; r < 3; r++)
+        for (int c = 0; c < 3; c++) {
+            m.vals[r][c] = A->vals[r][0] * B->vals[0][c]
+                         + A->vals[r][1] * B->vals[1][c]
+                         + A->vals[r][2] * B->vals[2][c];
+        }
+    return m;
+}
+
+skcms_Vector3 skcms_MV_mul(const skcms_Matrix3x3* m, const skcms_Vector3* v) {
+    skcms_Vector3 dst = {{0,0,0}};
+    for (int row = 0; row < 3; ++row) {
+        dst.vals[row] = m->vals[row][0] * v->vals[0]
+                      + m->vals[row][1] * v->vals[1]
+                      + m->vals[row][2] * v->vals[2];
+    }
+    return dst;
+}
+
+#if defined(__clang__) || defined(__GNUC__)
+    #define small_memcpy __builtin_memcpy
+#else
+    #define small_memcpy memcpy
+#endif
+
+float log2f_(float x) {
+    // The first approximation of log2(x) is its exponent 'e', minus 127.
+    int32_t bits;
+    small_memcpy(&bits, &x, sizeof(bits));
+
+    float e = (float)bits * (1.0f / (1<<23));
+
+    // If we use the mantissa too we can refine the error signficantly.
+    int32_t m_bits = (bits & 0x007fffff) | 0x3f000000;
+    float m;
+    small_memcpy(&m, &m_bits, sizeof(m));
+
+    return (e - 124.225514990f
+              -   1.498030302f*m
+              -   1.725879990f/(0.3520887068f + m));
+}
+
+float exp2f_(float x) {
+    float fract = x - floorf_(x);
+
+    float fbits = (1.0f * (1<<23)) * (x + 121.274057500f
+                                        -   1.490129070f*fract
+                                        +  27.728023300f/(4.84252568f - fract));
+    if (fbits > INT_MAX) {
+        return INFINITY_;
+    } else if (fbits < INT_MIN) {
+        return -INFINITY_;
+    }
+    int32_t bits = (int32_t)fbits;
+    small_memcpy(&x, &bits, sizeof(x));
+    return x;
+}
+
+float powf_(float x, float y) {
+    return (x == 0) || (x == 1) ? x
+                                : exp2f_(log2f_(x) * y);
+}
+
+float skcms_TransferFunction_eval(const skcms_TransferFunction* tf, float x) {
+    float sign = x < 0 ? -1.0f : 1.0f;
+    x *= sign;
+
+    return sign * (x < tf->d ? tf->c * x + tf->f
+                             : powf_(tf->a * x + tf->b, tf->g) + tf->e);
+}
+
+bool skcms_TransferFunction_isValid(const skcms_TransferFunction* tf) {
+    // Reject obviously malformed inputs
+    if (!isfinitef_(tf->a + tf->b + tf->c + tf->d + tf->e + tf->f + tf->g)) {
+        return false;
+    }
+
+    // All of these parameters should be non-negative
+    if (tf->a < 0 || tf->c < 0 || tf->d < 0 || tf->g < 0) {
+        return false;
+    }
+
+    return true;
+}
+
+// TODO: Adjust logic here? This still assumes that purely linear inputs will have D > 1, which
+// we never generate. It also emits inverted linear using the same formulation. Standardize on
+// G == 1 here, too?
+bool skcms_TransferFunction_invert(const skcms_TransferFunction* src, skcms_TransferFunction* dst) {
+    // Original equation is:       y = (ax + b)^g + e   for x >= d
+    //                             y = cx + f           otherwise
+    //
+    // so 1st inverse is:          (y - e)^(1/g) = ax + b
+    //                             x = ((y - e)^(1/g) - b) / a
+    //
+    // which can be re-written as: x = (1/a)(y - e)^(1/g) - b/a
+    //                             x = ((1/a)^g)^(1/g) * (y - e)^(1/g) - b/a
+    //                             x = ([(1/a)^g]y + [-((1/a)^g)e]) ^ [1/g] + [-b/a]
+    //
+    // and 2nd inverse is:         x = (y - f) / c
+    // which can be re-written as: x = [1/c]y + [-f/c]
+    //
+    // and now both can be expressed in terms of the same parametric form as the
+    // original - parameters are enclosed in square brackets.
+    skcms_TransferFunction tf_inv = { 0, 0, 0, 0, 0, 0, 0 };
+
+    // This rejects obviously malformed inputs, as well as decreasing functions
+    if (!skcms_TransferFunction_isValid(src)) {
+        return false;
+    }
+
+    // There are additional constraints to be invertible
+    bool has_nonlinear = (src->d <= 1);
+    bool has_linear = (src->d > 0);
+
+    // Is the linear section not invertible?
+    if (has_linear && src->c == 0) {
+        return false;
+    }
+
+    // Is the nonlinear section not invertible?
+    if (has_nonlinear && (src->a == 0 || src->g == 0)) {
+        return false;
+    }
+
+    // If both segments are present, they need to line up
+    if (has_linear && has_nonlinear) {
+        float l_at_d = src->c * src->d + src->f;
+        float n_at_d = powf_(src->a * src->d + src->b, src->g) + src->e;
+        if (fabsf_(l_at_d - n_at_d) > (1 / 512.0f)) {
+            return false;
+        }
+    }
+
+    // Invert linear segment
+    if (has_linear) {
+        tf_inv.c = 1.0f / src->c;
+        tf_inv.f = -src->f / src->c;
+    }
+
+    // Invert nonlinear segment
+    if (has_nonlinear) {
+        tf_inv.g = 1.0f / src->g;
+        tf_inv.a = powf_(1.0f / src->a, src->g);
+        tf_inv.b = -tf_inv.a * src->e;
+        tf_inv.e = -src->b / src->a;
+    }
+
+    if (!has_linear) {
+        tf_inv.d = 0;
+    } else if (!has_nonlinear) {
+        // Any value larger than 1 works
+        tf_inv.d = 2.0f;
+    } else {
+        tf_inv.d = src->c * src->d + src->f;
+    }
+
+    *dst = tf_inv;
+    return true;
+}
+
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //
+
+// From here below we're approximating an skcms_Curve with an skcms_TransferFunction{g,a,b,c,d,e,f}:
+//
+//   tf(x) =  cx + f          x < d
+//   tf(x) = (ax + b)^g + e   x ≥ d
+//
+// When fitting, we add the additional constraint that both pieces meet at d:
+//
+//   cd + f = (ad + b)^g + e
+//
+// Solving for e and folding it through gives an alternate formulation of the non-linear piece:
+//
+//   tf(x) =                           cx + f   x < d
+//   tf(x) = (ax + b)^g - (ad + b)^g + cd + f   x ≥ d
+//
+// Our overall strategy is then:
+//    For a couple tolerances,
+//       - skcms_fit_linear(): fit c,d,f iteratively to as many points as our tolerance allows
+//       - invert c,d,f
+//       - fit_nonlinear():    fit g,a,b using Gauss-Newton given those inverted c,d,f
+//                             (and by constraint, inverted e) to the inverse of the table.
+//    Return the parameters with least maximum error.
+//
+// To run Gauss-Newton to find g,a,b, we'll also need the gradient of the residuals
+// of round-trip f_inv(x), the inverse of the non-linear piece of f(x).
+//
+//    let y = Table(x)
+//    r(x) = x - f_inv(y)
+//
+//    ∂r/∂g = ln(ay + b)*(ay + b)^g
+//          - ln(ad + b)*(ad + b)^g
+//    ∂r/∂a = yg(ay + b)^(g-1)
+//          - dg(ad + b)^(g-1)
+//    ∂r/∂b =  g(ay + b)^(g-1)
+//          -  g(ad + b)^(g-1)
+
+// Return the residual of roundtripping skcms_Curve(x) through f_inv(y) with parameters P,
+// and fill out the gradient of the residual into dfdP.
+static float rg_nonlinear(float x,
+                          const skcms_Curve* curve,
+                          const skcms_TransferFunction* tf,
+                          const float P[3],
+                          float dfdP[3]) {
+    const float y = skcms_eval_curve(curve, x);
+
+    const float g = P[0],  a = P[1],  b = P[2],
+                c = tf->c, d = tf->d, f = tf->f;
+
+    const float Y = fmaxf_(a*y + b, 0.0f),
+                D =        a*d + b;
+    assert (D >= 0);
+
+    // The gradient.
+    dfdP[0] = 0.69314718f*log2f_(Y)*powf_(Y, g)
+            - 0.69314718f*log2f_(D)*powf_(D, g);
+    dfdP[1] = y*g*powf_(Y, g-1)
+            - d*g*powf_(D, g-1);
+    dfdP[2] =   g*powf_(Y, g-1)
+            -   g*powf_(D, g-1);
+
+    // The residual.
+    const float f_inv = powf_(Y, g)
+                      - powf_(D, g)
+                      + c*d + f;
+    return x - f_inv;
+}
+
+int skcms_fit_linear(const skcms_Curve* curve, int N, float tol, float* c, float* d, float* f) {
+    assert(N > 1);
+    // We iteratively fit the first points to the TF's linear piece.
+    // We want the cx + f line to pass through the first and last points we fit exactly.
+    //
+    // As we walk along the points we find the minimum and maximum slope of the line before the
+    // error would exceed our tolerance.  We stop when the range [slope_min, slope_max] becomes
+    // emtpy, when we definitely can't add any more points.
+    //
+    // Some points' error intervals may intersect the running interval but not lie fully
+    // within it.  So we keep track of the last point we saw that is a valid end point candidate,
+    // and once the search is done, back up to build the line through *that* point.
+    const float dx = 1.0f / (N - 1);
+
+    int lin_points = 1;
+    *f = skcms_eval_curve(curve, 0);
+
+    float slope_min = -INFINITY_;
+    float slope_max = +INFINITY_;
+    for (int i = 1; i < N; ++i) {
+        float x = i * dx;
+        float y = skcms_eval_curve(curve, x);
+
+        float slope_max_i = (y + tol - *f) / x,
+              slope_min_i = (y - tol - *f) / x;
+        if (slope_max_i < slope_min || slope_max < slope_min_i) {
+            // Slope intervals would no longer overlap.
+            break;
+        }
+        slope_max = fminf_(slope_max, slope_max_i);
+        slope_min = fmaxf_(slope_min, slope_min_i);
+
+        float cur_slope = (y - *f) / x;
+        if (slope_min <= cur_slope && cur_slope <= slope_max) {
+            lin_points = i + 1;
+            *c = cur_slope;
+        }
+    }
+
+    // Set D to the last point that met our tolerance.
+    *d = (lin_points - 1) * dx;
+    return lin_points;
+}
+
+static bool gauss_newton_step(const skcms_Curve* curve,
+                              const skcms_TransferFunction* tf,
+                              float P[3],
+                              float x0, float dx, int N) {
+    // We'll sample x from the range [x0,x1] (both inclusive) N times with even spacing.
+    //
+    // We want to do P' = P + (Jf^T Jf)^-1 Jf^T r(P),
+    //   where r(P) is the residual vector
+    //   and Jf is the Jacobian matrix of f(), ∂r/∂P.
+    //
+    // Let's review the shape of each of these expressions:
+    //   r(P)   is [N x 1], a column vector with one entry per value of x tested
+    //   Jf     is [N x 3], a matrix with an entry for each (x,P) pair
+    //   Jf^T   is [3 x N], the transpose of Jf
+    //
+    //   Jf^T Jf   is [3 x N] * [N x 3] == [3 x 3], a 3x3 matrix,
+    //                                              and so is its inverse (Jf^T Jf)^-1
+    //   Jf^T r(P) is [3 x N] * [N x 1] == [3 x 1], a column vector with the same shape as P
+    //
+    // Our implementation strategy to get to the final ∆P is
+    //   1) evaluate Jf^T Jf,   call that lhs
+    //   2) evaluate Jf^T r(P), call that rhs
+    //   3) invert lhs
+    //   4) multiply inverse lhs by rhs
+    //
+    // This is a friendly implementation strategy because we don't have to have any
+    // buffers that scale with N, and equally nice don't have to perform any matrix
+    // operations that are variable size.
+    //
+    // Other implementation strategies could trade this off, e.g. evaluating the
+    // pseudoinverse of Jf ( (Jf^T Jf)^-1 Jf^T ) directly, then multiplying that by
+    // the residuals.  That would probably require implementing singular value
+    // decomposition, and would create a [3 x N] matrix to be multiplied by the
+    // [N x 1] residual vector, but on the upside I think that'd eliminate the
+    // possibility of this gauss_newton_step() function ever failing.
+
+    // 0) start off with lhs and rhs safely zeroed.
+    skcms_Matrix3x3 lhs = {{ {0,0,0}, {0,0,0}, {0,0,0} }};
+    skcms_Vector3   rhs = {  {0,0,0} };
+
+    // 1,2) evaluate lhs and evaluate rhs
+    //   We want to evaluate Jf only once, but both lhs and rhs involve Jf^T,
+    //   so we'll have to update lhs and rhs at the same time.
+    for (int i = 0; i < N; i++) {
+        float x = x0 + i*dx;
+
+        float dfdP[3] = {0,0,0};
+        float resid = rg_nonlinear(x,curve,tf,P, dfdP);
+
+        for (int r = 0; r < 3; r++) {
+            for (int c = 0; c < 3; c++) {
+                lhs.vals[r][c] += dfdP[r] * dfdP[c];
+            }
+            rhs.vals[r] += dfdP[r] * resid;
+        }
+    }
+
+    // If any of the 3 P parameters are unused, this matrix will be singular.
+    // Detect those cases and fix them up to indentity instead, so we can invert.
+    for (int k = 0; k < 3; k++) {
+        if (lhs.vals[0][k]==0 && lhs.vals[1][k]==0 && lhs.vals[2][k]==0 &&
+            lhs.vals[k][0]==0 && lhs.vals[k][1]==0 && lhs.vals[k][2]==0) {
+            lhs.vals[k][k] = 1;
+        }
+    }
+
+    // 3) invert lhs
+    skcms_Matrix3x3 lhs_inv;
+    if (!skcms_Matrix3x3_invert(&lhs, &lhs_inv)) {
+        return false;
+    }
+
+    // 4) multiply inverse lhs by rhs
+    skcms_Vector3 dP = skcms_MV_mul(&lhs_inv, &rhs);
+    P[0] += dP.vals[0];
+    P[1] += dP.vals[1];
+    P[2] += dP.vals[2];
+    return isfinitef_(P[0]) && isfinitef_(P[1]) && isfinitef_(P[2]);
+}
+
+
+// Fit the points in [L,N) to the non-linear piece of tf, or return false if we can't.
+static bool fit_nonlinear(const skcms_Curve* curve, int L, int N, skcms_TransferFunction* tf) {
+    float P[3] = { tf->g, tf->a, tf->b };
+
+    // No matter where we start, dx should always represent N even steps from 0 to 1.
+    const float dx = 1.0f / (N-1);
+
+    for (int j = 0; j < 3/*TODO: tune*/; j++) {
+        // These extra constraints a >= 0 and ad+b >= 0 are not modeled in the optimization.
+        // We don't really know how to fix up a if it goes negative.
+        if (P[1] < 0) {
+            return false;
+        }
+        // If ad+b goes negative, we feel just barely not uneasy enough to tweak b so ad+b is zero.
+        if (P[1] * tf->d + P[2] < 0) {
+            P[2] = -P[1] * tf->d;
+        }
+        assert (P[1] >= 0 &&
+                P[1] * tf->d + P[2] >= 0);
+
+        if (!gauss_newton_step(curve, tf,
+                               P,
+                               L*dx, dx, N-L)) {
+            return false;
+        }
+    }
+
+    // We need to apply our fixups one last time
+    if (P[1] < 0) {
+        return false;
+    }
+    if (P[1] * tf->d + P[2] < 0) {
+        P[2] = -P[1] * tf->d;
+    }
+
+    tf->g = P[0];
+    tf->a = P[1];
+    tf->b = P[2];
+    tf->e =   tf->c*tf->d + tf->f
+      - powf_(tf->a*tf->d + tf->b, tf->g);
+    return true;
+}
+
+bool skcms_ApproximateCurve(const skcms_Curve* curve,
+                            skcms_TransferFunction* approx,
+                            float* max_error) {
+    if (!curve || !approx || !max_error) {
+        return false;
+    }
+
+    if (curve->table_entries == 0) {
+        // No point approximating an skcms_TransferFunction with an skcms_TransferFunction!
+        return false;
+    }
+
+    if (curve->table_entries == 1 || curve->table_entries > (uint32_t)INT_MAX) {
+        // We need at least two points, and must put some reasonable cap on the maximum number.
+        return false;
+    }
+
+    int N = (int)curve->table_entries;
+    const float dx = 1.0f / (N - 1);
+
+    *max_error = INFINITY_;
+    const float kTolerances[] = { 1.5f / 65535.0f, 1.0f / 512.0f };
+    for (int t = 0; t < ARRAY_COUNT(kTolerances); t++) {
+        skcms_TransferFunction tf,
+                               tf_inv;
+        int L = skcms_fit_linear(curve, N, kTolerances[t], &tf.c, &tf.d, &tf.f);
+
+        if (L == N) {
+            // If the entire data set was linear, move the coefficients to the nonlinear portion
+            // with G == 1.  This lets use a canonical representation with d == 0.
+            tf.g = 1;
+            tf.a = tf.c;
+            tf.b = tf.f;
+            tf.c = tf.d = tf.e = tf.f = 0;
+        } else if (L == N - 1) {
+            // Degenerate case with only two points in the nonlinear segment. Solve directly.
+            tf.g = 1;
+            tf.a = (skcms_eval_curve(curve, (N-1)*dx) -
+                    skcms_eval_curve(curve, (N-2)*dx))
+                 / dx;
+            tf.b = skcms_eval_curve(curve, (N-2)*dx)
+                 - tf.a * (N-2)*dx;
+            tf.e = 0;
+        } else {
+            // Start by guessing a gamma-only curve through the midpoint.
+            int mid = (L + N) / 2;
+            float mid_x = mid / (N - 1.0f);
+            float mid_y = skcms_eval_curve(curve, mid_x);
+            tf.g = log2f_(mid_y) / log2f_(mid_x);;
+            tf.a = 1;
+            tf.b = 0;
+            tf.e =    tf.c*tf.d + tf.f
+              - powf_(tf.a*tf.d + tf.b, tf.g);
+
+
+            if (!skcms_TransferFunction_invert(&tf, &tf_inv) ||
+                !fit_nonlinear(curve, L,N, &tf_inv)) {
+                continue;
+            }
+
+            // We fit tf_inv, so calculate tf to keep in sync.
+            if (!skcms_TransferFunction_invert(&tf_inv, &tf)) {
+                continue;
+            }
+        }
+
+        // We find our error by roundtripping the table through tf_inv.
+        //
+        // (The most likely use case for this approximation is to be inverted and
+        // used as the transfer function for a destination color space.)
+        //
+        // We've kept tf and tf_inv in sync above, but we can't guarantee that tf is
+        // invertible, so re-verify that here (and use the new inverse for testing).
+        if (!skcms_TransferFunction_invert(&tf, &tf_inv)) {
+            continue;
+        }
+
+        float err = skcms_MaxRoundtripError(curve, &tf_inv);
+        if (*max_error > err) {
+            *max_error = err;
+            *approx    = tf;
+        }
+    }
+    return isfinitef_(*max_error);
+}
+
+// Without this wasm would try to use the N=4 128-bit vector code path,
+// which while ideal, causes tons of compiler problems.  This would be
+// a good thing to revisit as emcc matures (currently 1.38.5).
+#if 1 && defined(__EMSCRIPTEN_major__)
+    #if !defined(SKCMS_PORTABLE)
+        #define  SKCMS_PORTABLE
+    #endif
+#endif
+
+extern bool g_skcms_dump_profile;
+bool g_skcms_dump_profile = false;
+
+#if !defined(NDEBUG) && defined(__clang__)
+    // Basic profiling tools to time each Op.  Not at all thread safe.
+
+    #include <stdio.h>
+    #include <stdlib.h>
+
+    #if defined(__arm__) || defined(__aarch64__)
+        #include <time.h>
+        static const char* now_units = "ticks";
+        static uint64_t now() { return (uint64_t)clock(); }
+    #else
+        static const char* now_units = "cycles";
+        static uint64_t now() { return __builtin_readcyclecounter(); }
+    #endif
+
+    #define M(op) +1
+    static uint64_t counts[FOREACH_Op(M)];
+    #undef M
+
+    static void profile_dump_stats() {
+    #define M(op) #op,
+        static const char* names[] = { FOREACH_Op(M) };
+    #undef M
+        for (int i = 0; i < ARRAY_COUNT(counts); i++) {
+            if (counts[i]) {
+                fprintf(stderr, "%16s: %12llu %s\n",
+                        names[i], (unsigned long long)counts[i], now_units);
+            }
+        }
+    }
+
+    static inline Op profile_next_op(Op op) {
+        if (__builtin_expect(g_skcms_dump_profile, false)) {
+            static uint64_t start    = 0;
+            static uint64_t* current = NULL;
+
+            if (!current) {
+                atexit(profile_dump_stats);
+            } else {
+                *current += now() - start;
+            }
+
+            current = &counts[op];
+            start   = now();
+        }
+        return op;
+    }
+#else
+    static inline Op profile_next_op(Op op) {
+        (void)g_skcms_dump_profile;
+        return op;
+    }
+#endif
+
+#if defined(__clang__)
+    typedef float    __attribute__((ext_vector_type(4)))   Fx4;
+    typedef int32_t  __attribute__((ext_vector_type(4))) I32x4;
+    typedef uint64_t __attribute__((ext_vector_type(4))) U64x4;
+    typedef uint32_t __attribute__((ext_vector_type(4))) U32x4;
+    typedef uint16_t __attribute__((ext_vector_type(4))) U16x4;
+    typedef uint8_t  __attribute__((ext_vector_type(4)))  U8x4;
+
+    typedef float    __attribute__((ext_vector_type(8)))   Fx8;
+    typedef int32_t  __attribute__((ext_vector_type(8))) I32x8;
+    typedef uint64_t __attribute__((ext_vector_type(8))) U64x8;
+    typedef uint32_t __attribute__((ext_vector_type(8))) U32x8;
+    typedef uint16_t __attribute__((ext_vector_type(8))) U16x8;
+    typedef uint8_t  __attribute__((ext_vector_type(8)))  U8x8;
+
+    typedef float    __attribute__((ext_vector_type(16)))   Fx16;
+    typedef int32_t  __attribute__((ext_vector_type(16))) I32x16;
+    typedef uint64_t __attribute__((ext_vector_type(16))) U64x16;
+    typedef uint32_t __attribute__((ext_vector_type(16))) U32x16;
+    typedef uint16_t __attribute__((ext_vector_type(16))) U16x16;
+    typedef uint8_t  __attribute__((ext_vector_type(16)))  U8x16;
+#elif defined(__GNUC__)
+    typedef float    __attribute__((vector_size(16)))   Fx4;
+    typedef int32_t  __attribute__((vector_size(16))) I32x4;
+    typedef uint64_t __attribute__((vector_size(32))) U64x4;
+    typedef uint32_t __attribute__((vector_size(16))) U32x4;
+    typedef uint16_t __attribute__((vector_size( 8))) U16x4;
+    typedef uint8_t  __attribute__((vector_size( 4)))  U8x4;
+
+    typedef float    __attribute__((vector_size(32)))   Fx8;
+    typedef int32_t  __attribute__((vector_size(32))) I32x8;
+    typedef uint64_t __attribute__((vector_size(64))) U64x8;
+    typedef uint32_t __attribute__((vector_size(32))) U32x8;
+    typedef uint16_t __attribute__((vector_size(16))) U16x8;
+    typedef uint8_t  __attribute__((vector_size( 8)))  U8x8;
+
+    typedef float    __attribute__((vector_size( 64)))   Fx16;
+    typedef int32_t  __attribute__((vector_size( 64))) I32x16;
+    typedef uint64_t __attribute__((vector_size(128))) U64x16;
+    typedef uint32_t __attribute__((vector_size( 64))) U32x16;
+    typedef uint16_t __attribute__((vector_size( 32))) U16x16;
+    typedef uint8_t  __attribute__((vector_size( 16)))  U8x16;
+#endif
+
+// First, instantiate our default exec_ops() implementation using the default compiliation target.
+
+#if defined(SKCMS_PORTABLE) || !(defined(__clang__) || defined(__GNUC__))
+    #define N 1
+
+    #define F   float
+    #define U64 uint64_t
+    #define U32 uint32_t
+    #define I32 int32_t
+    #define U16 uint16_t
+    #define U8  uint8_t
+
+    #define F0 0.0f
+    #define F1 1.0f
+
+#elif defined(__AVX512F__)
+    #define N 16
+
+    #define F     Fx16
+    #define U64 U64x16
+    #define U32 U32x16
+    #define I32 I32x16
+    #define U16 U16x16
+    #define U8   U8x16
+
+    #define F0 (F){0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0}
+    #define F1 (F){1,1,1,1, 1,1,1,1, 1,1,1,1, 1,1,1,1}
+#elif defined(__AVX__)
+    #define N 8
+
+    #define F     Fx8
+    #define U64 U64x8
+    #define U32 U32x8
+    #define I32 I32x8
+    #define U16 U16x8
+    #define U8   U8x8
+
+    #define F0 (F){0,0,0,0, 0,0,0,0}
+    #define F1 (F){1,1,1,1, 1,1,1,1}
+#else
+    #define N 4
+
+    #define F     Fx4
+    #define U64 U64x4
+    #define U32 U32x4
+    #define I32 I32x4
+    #define U16 U16x4
+    #define U8   U8x4
+
+    #define F0 (F){0,0,0,0}
+    #define F1 (F){1,1,1,1}
+#endif
+
+#define NS(id) id
+#define ATTR
+    #include "src/Transform_inl.h"
+#undef N
+#undef F
+#undef U64
+#undef U32
+#undef I32
+#undef U16
+#undef U8
+#undef F0
+#undef F1
+#undef NS
+#undef ATTR
+
+// Now, instantiate any other versions of run_program() we may want for runtime detection.
+#if !defined(SKCMS_PORTABLE) && (defined(__clang__) || defined(__GNUC__)) \
+        && defined(__x86_64__) && !defined(__AVX2__)
+    #define N 8
+    #define F     Fx8
+    #define U64 U64x8
+    #define U32 U32x8
+    #define I32 I32x8
+    #define U16 U16x8
+    #define U8   U8x8
+    #define F0 (F){0,0,0,0, 0,0,0,0}
+    #define F1 (F){1,1,1,1, 1,1,1,1}
+
+    #define NS(id) id ## _hsw
+    #define ATTR __attribute__((target("avx2,f16c")))
+
+    // We check these guards to see if we have support for these features.
+    // They're likely _not_ defined here in our baseline build config.
+    #ifndef __AVX__
+        #define __AVX__ 1
+        #define UNDEF_AVX
+    #endif
+    #ifndef __F16C__
+        #define __F16C__ 1
+        #define UNDEF_F16C
+    #endif
+    #ifndef __AVX2__
+        #define __AVX2__ 1
+        #define UNDEF_AVX2
+    #endif
+
+    #include "src/Transform_inl.h"
+
+    #undef N
+    #undef F
+    #undef U64
+    #undef U32
+    #undef I32
+    #undef U16
+    #undef U8
+    #undef F0
+    #undef F1
+    #undef NS
+    #undef ATTR
+
+    #ifdef UNDEF_AVX
+        #undef __AVX__
+        #undef UNDEF_AVX
+    #endif
+    #ifdef UNDEF_F16C
+        #undef __F16C__
+        #undef UNDEF_F16C
+    #endif
+    #ifdef UNDEF_AVX2
+        #undef __AVX2__
+        #undef UNDEF_AVX2
+    #endif
+
+    #define TEST_FOR_HSW
+
+    static bool hsw_ok_ = false;
+    static void check_hsw_ok() {
+        // See http://www.sandpile.org/x86/cpuid.htm
+
+        // First, a basic cpuid(1).
+        uint32_t eax, ebx, ecx, edx;
+        __asm__ __volatile__("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
+                                     : "0"(1), "2"(0));
+
+        // Sanity check for prerequisites.
+        if ((edx & (1<<25)) != (1<<25)) { return; }   // SSE
+        if ((edx & (1<<26)) != (1<<26)) { return; }   // SSE2
+        if ((ecx & (1<< 0)) != (1<< 0)) { return; }   // SSE3
+        if ((ecx & (1<< 9)) != (1<< 9)) { return; }   // SSSE3
+        if ((ecx & (1<<19)) != (1<<19)) { return; }   // SSE4.1
+        if ((ecx & (1<<20)) != (1<<20)) { return; }   // SSE4.2
+
+        if ((ecx & (3<<26)) != (3<<26)) { return; }   // XSAVE + OSXSAVE
+
+        {
+            uint32_t eax_xgetbv, edx_xgetbv;
+            __asm__ __volatile__("xgetbv" : "=a"(eax_xgetbv), "=d"(edx_xgetbv) : "c"(0));
+            if ((eax_xgetbv & (3<<1)) != (3<<1)) { return; }  // XMM+YMM state saved?
+        }
+
+        if ((ecx & (1<<28)) != (1<<28)) { return; }   // AVX
+        if ((ecx & (1<<29)) != (1<<29)) { return; }   // F16C
+        if ((ecx & (1<<12)) != (1<<12)) { return; }   // FMA  (TODO: not currently used)
+
+        // Call cpuid(7) to check for our final AVX2 feature bit!
+        __asm__ __volatile__("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
+                                     : "0"(7), "2"(0));
+        if ((ebx & (1<< 5)) != (1<< 5)) { return; }   // AVX2
+
+        hsw_ok_ = true;
+    }
+
+    #if defined(_MSC_VER)
+        #include <Windows.h>
+        INIT_ONCE check_hsw_ok_once = INIT_ONCE_STATIC_INIT;
+
+        static BOOL check_hsw_ok_InitOnce_wrapper(INIT_ONCE* once, void* param, void** ctx) {
+            (void)once;
+            (void)param;
+            (void)ctx;
+            check_hsw_ok();
+            return TRUE;
+        }
+
+        static bool hsw_ok() {
+            InitOnceExecuteOnce(&check_hsw_ok_once, check_hsw_ok_InitOnce_wrapper, NULL, NULL);
+            return hsw_ok_;
+        }
+    #else
+        #include <pthread.h>
+        static pthread_once_t check_hsw_ok_once = PTHREAD_ONCE_INIT;
+
+        static bool hsw_ok() {
+            pthread_once(&check_hsw_ok_once, check_hsw_ok);
+            return hsw_ok_;
+        }
+    #endif
+
+#endif
+
+static bool is_identity_tf(const skcms_TransferFunction* tf) {
+    return tf->g == 1 && tf->a == 1
+        && tf->b == 0 && tf->c == 0 && tf->d == 0 && tf->e == 0 && tf->f == 0;
+}
+
+typedef struct {
+    Op          op;
+    const void* arg;
+} OpAndArg;
+
+static OpAndArg select_curve_op(const skcms_Curve* curve, int channel) {
+    static const struct { Op parametric, table_8, table_16; } ops[] = {
+        { Op_tf_r, Op_table_8_r, Op_table_16_r },
+        { Op_tf_g, Op_table_8_g, Op_table_16_g },
+        { Op_tf_b, Op_table_8_b, Op_table_16_b },
+        { Op_tf_a, Op_table_8_a, Op_table_16_a },
+    };
+
+    if (curve->table_entries == 0) {
+        return is_identity_tf(&curve->parametric)
+            ? (OpAndArg){ Op_noop, NULL }
+            : (OpAndArg){ ops[channel].parametric, &curve->parametric };
+    } else if (curve->table_8) {
+        return (OpAndArg){ ops[channel].table_8,  curve };
+    } else if (curve->table_16) {
+        return (OpAndArg){ ops[channel].table_16, curve };
+    }
+
+    assert(false);
+    return (OpAndArg){Op_noop,NULL};
+}
+
+static size_t bytes_per_pixel(skcms_PixelFormat fmt) {
+    switch (fmt >> 1) {   // ignore rgb/bgr
+        case skcms_PixelFormat_A_8           >> 1: return  1;
+        case skcms_PixelFormat_G_8           >> 1: return  1;
+        case skcms_PixelFormat_ABGR_4444     >> 1: return  2;
+        case skcms_PixelFormat_RGB_565       >> 1: return  2;
+        case skcms_PixelFormat_RGB_888       >> 1: return  3;
+        case skcms_PixelFormat_RGBA_8888     >> 1: return  4;
+        case skcms_PixelFormat_RGBA_1010102  >> 1: return  4;
+        case skcms_PixelFormat_RGB_161616    >> 1: return  6;
+        case skcms_PixelFormat_RGBA_16161616 >> 1: return  8;
+        case skcms_PixelFormat_RGB_hhh       >> 1: return  6;
+        case skcms_PixelFormat_RGBA_hhhh     >> 1: return  8;
+        case skcms_PixelFormat_RGB_fff       >> 1: return 12;
+        case skcms_PixelFormat_RGBA_ffff     >> 1: return 16;
+    }
+    assert(false);
+    return 0;
+}
+
+static bool prep_for_destination(const skcms_ICCProfile* profile,
+                                 skcms_Matrix3x3* fromXYZD50,
+                                 skcms_TransferFunction* invR,
+                                 skcms_TransferFunction* invG,
+                                 skcms_TransferFunction* invB) {
+    // We only support destinations with parametric transfer functions
+    // and with gamuts that can be transformed from XYZD50.
+    return profile->has_trc
+        && profile->has_toXYZD50
+        && profile->trc[0].table_entries == 0
+        && profile->trc[1].table_entries == 0
+        && profile->trc[2].table_entries == 0
+        && skcms_TransferFunction_invert(&profile->trc[0].parametric, invR)
+        && skcms_TransferFunction_invert(&profile->trc[1].parametric, invG)
+        && skcms_TransferFunction_invert(&profile->trc[2].parametric, invB)
+        && skcms_Matrix3x3_invert(&profile->toXYZD50, fromXYZD50);
+}
+
+bool skcms_Transform(const void*             src,
+                     skcms_PixelFormat       srcFmt,
+                     skcms_AlphaFormat       srcAlpha,
+                     const skcms_ICCProfile* srcProfile,
+                     void*                   dst,
+                     skcms_PixelFormat       dstFmt,
+                     skcms_AlphaFormat       dstAlpha,
+                     const skcms_ICCProfile* dstProfile,
+                     size_t                  nz) {
+    const size_t dst_bpp = bytes_per_pixel(dstFmt),
+                 src_bpp = bytes_per_pixel(srcFmt);
+    // Let's just refuse if the request is absurdly big.
+    if (nz * dst_bpp > INT_MAX || nz * src_bpp > INT_MAX) {
+        return false;
+    }
+    int n = (int)nz;
+
+    // Null profiles default to sRGB. Passing null for both is handy when doing format conversion.
+    if (!srcProfile) {
+        srcProfile = skcms_sRGB_profile();
+    }
+    if (!dstProfile) {
+        dstProfile = skcms_sRGB_profile();
+    }
+
+    // We can't transform in place unless the PixelFormats are the same size.
+    if (dst == src && (dstFmt >> 1) != (srcFmt >> 1)) {
+        return false;
+    }
+    // TODO: this check lazilly disallows U16 <-> F16, but that would actually be fine.
+    // TODO: more careful alias rejection (like, dst == src + 1)?
+
+    Op          program  [32];
+    const void* arguments[32];
+
+    Op*          ops  = program;
+    const void** args = arguments;
+
+    skcms_TransferFunction inv_dst_tf_r, inv_dst_tf_g, inv_dst_tf_b;
+    skcms_Matrix3x3        from_xyz;
+
+    switch (srcFmt >> 1) {
+        default: return false;
+        case skcms_PixelFormat_A_8           >> 1: *ops++ = Op_load_a8;       break;
+        case skcms_PixelFormat_G_8           >> 1: *ops++ = Op_load_g8;       break;
+        case skcms_PixelFormat_ABGR_4444     >> 1: *ops++ = Op_load_4444;     break;
+        case skcms_PixelFormat_RGB_565       >> 1: *ops++ = Op_load_565;      break;
+        case skcms_PixelFormat_RGB_888       >> 1: *ops++ = Op_load_888;      break;
+        case skcms_PixelFormat_RGBA_8888     >> 1: *ops++ = Op_load_8888;     break;
+        case skcms_PixelFormat_RGBA_1010102  >> 1: *ops++ = Op_load_1010102;  break;
+        case skcms_PixelFormat_RGB_161616    >> 1: *ops++ = Op_load_161616;   break;
+        case skcms_PixelFormat_RGBA_16161616 >> 1: *ops++ = Op_load_16161616; break;
+        case skcms_PixelFormat_RGB_hhh       >> 1: *ops++ = Op_load_hhh;      break;
+        case skcms_PixelFormat_RGBA_hhhh     >> 1: *ops++ = Op_load_hhhh;     break;
+        case skcms_PixelFormat_RGB_fff       >> 1: *ops++ = Op_load_fff;      break;
+        case skcms_PixelFormat_RGBA_ffff     >> 1: *ops++ = Op_load_ffff;     break;
+    }
+    if (srcFmt & 1) {
+        *ops++ = Op_swap_rb;
+    }
+    skcms_ICCProfile gray_dst_profile;
+    if ((dstFmt >> 1) == (skcms_PixelFormat_G_8 >> 1)) {
+        // When transforming to gray, stop at XYZ (by setting toXYZ to identity), then transform
+        // luminance (Y) by the destination transfer function.
+        gray_dst_profile = *dstProfile;
+        skcms_SetXYZD50(&gray_dst_profile, &skcms_XYZD50_profile()->toXYZD50);
+        dstProfile = &gray_dst_profile;
+    }
+
+    if (srcProfile->data_color_space == skcms_Signature_CMYK) {
+        // Photoshop creates CMYK images as inverse CMYK.
+        // These happen to be the only ones we've _ever_ seen.
+        *ops++ = Op_invert;
+        // With CMYK, ignore the alpha type, to avoid changing K or conflating CMY with K.
+        srcAlpha = skcms_AlphaFormat_Unpremul;
+    }
+
+    if (srcAlpha == skcms_AlphaFormat_Opaque) {
+        *ops++ = Op_force_opaque;
+    } else if (srcAlpha == skcms_AlphaFormat_PremulAsEncoded) {
+        *ops++ = Op_unpremul;
+    }
+
+    // TODO: We can skip this work if both srcAlpha and dstAlpha are PremulLinear, and the profiles
+    // are the same. Also, if dstAlpha is PremulLinear, and SrcAlpha is Opaque.
+    if (dstProfile != srcProfile ||
+        srcAlpha == skcms_AlphaFormat_PremulLinear ||
+        dstAlpha == skcms_AlphaFormat_PremulLinear) {
+
+        if (!prep_for_destination(dstProfile,
+                                  &from_xyz, &inv_dst_tf_r, &inv_dst_tf_b, &inv_dst_tf_g)) {
+            return false;
+        }
+
+        if (srcProfile->has_A2B) {
+            if (srcProfile->A2B.input_channels) {
+                for (int i = 0; i < (int)srcProfile->A2B.input_channels; i++) {
+                    OpAndArg oa = select_curve_op(&srcProfile->A2B.input_curves[i], i);
+                    if (oa.op != Op_noop) {
+                        *ops++  = oa.op;
+                        *args++ = oa.arg;
+                    }
+                }
+                switch (srcProfile->A2B.input_channels) {
+                    case 3: *ops++ = srcProfile->A2B.grid_8 ? Op_clut_3D_8 : Op_clut_3D_16; break;
+                    case 4: *ops++ = srcProfile->A2B.grid_8 ? Op_clut_4D_8 : Op_clut_4D_16; break;
+                    default: return false;
+                }
+                *args++ = &srcProfile->A2B;
+            }
+
+            if (srcProfile->A2B.matrix_channels == 3) {
+                for (int i = 0; i < 3; i++) {
+                    OpAndArg oa = select_curve_op(&srcProfile->A2B.matrix_curves[i], i);
+                    if (oa.op != Op_noop) {
+                        *ops++  = oa.op;
+                        *args++ = oa.arg;
+                    }
+                }
+
+                static const skcms_Matrix3x4 I = {{
+                    {1,0,0,0},
+                    {0,1,0,0},
+                    {0,0,1,0},
+                }};
+                if (0 != memcmp(&I, &srcProfile->A2B.matrix, sizeof(I))) {
+                    *ops++  = Op_matrix_3x4;
+                    *args++ = &srcProfile->A2B.matrix;
+                }
+            }
+
+            if (srcProfile->A2B.output_channels == 3) {
+                for (int i = 0; i < 3; i++) {
+                    OpAndArg oa = select_curve_op(&srcProfile->A2B.output_curves[i], i);
+                    if (oa.op != Op_noop) {
+                        *ops++  = oa.op;
+                        *args++ = oa.arg;
+                    }
+                }
+            }
+
+            if (srcProfile->pcs == skcms_Signature_Lab) {
+                *ops++ = Op_lab_to_xyz;
+            }
+
+        } else if (srcProfile->has_trc && srcProfile->has_toXYZD50) {
+            for (int i = 0; i < 3; i++) {
+                OpAndArg oa = select_curve_op(&srcProfile->trc[i], i);
+                if (oa.op != Op_noop) {
+                    *ops++  = oa.op;
+                    *args++ = oa.arg;
+                }
+            }
+        } else {
+            return false;
+        }
+
+        // At this point our source colors are linear, either RGB (XYZ-type profiles)
+        // or XYZ (A2B-type profiles). Unpremul is a linear operation (multiply by a
+        // constant 1/a), so either way we can do it now if needed.
+        if (srcAlpha == skcms_AlphaFormat_PremulLinear) {
+            *ops++ = Op_unpremul;
+        }
+
+        // A2B sources should already be in XYZD50 at this point.
+        // Others still need to be transformed using their toXYZD50 matrix.
+        // N.B. There are profiles that contain both A2B tags and toXYZD50 matrices.
+        // If we use the A2B tags, we need to ignore the XYZD50 matrix entirely.
+        assert (srcProfile->has_A2B || srcProfile->has_toXYZD50);
+        static const skcms_Matrix3x3 I = {{
+            { 1.0f, 0.0f, 0.0f },
+            { 0.0f, 1.0f, 0.0f },
+            { 0.0f, 0.0f, 1.0f },
+        }};
+        const skcms_Matrix3x3* to_xyz = srcProfile->has_A2B ? &I : &srcProfile->toXYZD50;
+
+        // There's a chance the source and destination gamuts are identical,
+        // in which case we can skip the gamut transform.
+        if (0 != memcmp(&dstProfile->toXYZD50, to_xyz, sizeof(skcms_Matrix3x3))) {
+            // Concat the entire gamut transform into from_xyz,
+            // now slightly misnamed but it's a handy spot to stash the result.
+            from_xyz = skcms_Matrix3x3_concat(&from_xyz, to_xyz);
+            *ops++  = Op_matrix_3x3;
+            *args++ = &from_xyz;
+        }
+
+        if (dstAlpha == skcms_AlphaFormat_PremulLinear) {
+            *ops++ = Op_premul;
+        }
+
+        // Encode back to dst RGB using its parametric transfer functions.
+        if (!is_identity_tf(&inv_dst_tf_r)) { *ops++ = Op_tf_r; *args++ = &inv_dst_tf_r; }
+        if (!is_identity_tf(&inv_dst_tf_g)) { *ops++ = Op_tf_g; *args++ = &inv_dst_tf_g; }
+        if (!is_identity_tf(&inv_dst_tf_b)) { *ops++ = Op_tf_b; *args++ = &inv_dst_tf_b; }
+    }
+
+    if (dstAlpha == skcms_AlphaFormat_Opaque) {
+        *ops++ = Op_force_opaque;
+    } else if (dstAlpha == skcms_AlphaFormat_PremulAsEncoded) {
+        *ops++ = Op_premul;
+    }
+    if (dstFmt & 1) {
+        *ops++ = Op_swap_rb;
+    }
+    if (dstFmt < skcms_PixelFormat_RGB_hhh) {
+        *ops++ = Op_clamp;
+    }
+    switch (dstFmt >> 1) {
+        default: return false;
+        case skcms_PixelFormat_A_8           >> 1: *ops++ = Op_store_a8;       break;
+        case skcms_PixelFormat_G_8           >> 1: *ops++ = Op_store_g8;       break;
+        case skcms_PixelFormat_ABGR_4444     >> 1: *ops++ = Op_store_4444;     break;
+        case skcms_PixelFormat_RGB_565       >> 1: *ops++ = Op_store_565;      break;
+        case skcms_PixelFormat_RGB_888       >> 1: *ops++ = Op_store_888;      break;
+        case skcms_PixelFormat_RGBA_8888     >> 1: *ops++ = Op_store_8888;     break;
+        case skcms_PixelFormat_RGBA_1010102  >> 1: *ops++ = Op_store_1010102;  break;
+        case skcms_PixelFormat_RGB_161616    >> 1: *ops++ = Op_store_161616;   break;
+        case skcms_PixelFormat_RGBA_16161616 >> 1: *ops++ = Op_store_16161616; break;
+        case skcms_PixelFormat_RGB_hhh       >> 1: *ops++ = Op_store_hhh;      break;
+        case skcms_PixelFormat_RGBA_hhhh     >> 1: *ops++ = Op_store_hhhh;     break;
+        case skcms_PixelFormat_RGB_fff       >> 1: *ops++ = Op_store_fff;      break;
+        case skcms_PixelFormat_RGBA_ffff     >> 1: *ops++ = Op_store_ffff;     break;
+    }
+
+    void (*run)(const Op*, const void**, const char*, char*, int, size_t,size_t) = run_program;
+#if defined(TEST_FOR_HSW)
+    if (hsw_ok()) {
+        run = run_program_hsw;
+    }
+#endif
+    run(program, arguments, src, dst, n, src_bpp,dst_bpp);
+    return true;
+}
+
+static void assert_usable_as_destination(const skcms_ICCProfile* profile) {
+#if defined(NDEBUG)
+    (void)profile;
+#else
+    skcms_Matrix3x3 fromXYZD50;
+    skcms_TransferFunction invR, invG, invB;
+    assert(prep_for_destination(profile, &fromXYZD50, &invR, &invG, &invB));
+#endif
+}
+
+bool skcms_MakeUsableAsDestination(skcms_ICCProfile* profile) {
+    skcms_Matrix3x3 fromXYZD50;
+    if (!profile->has_trc || !profile->has_toXYZD50
+        || !skcms_Matrix3x3_invert(&profile->toXYZD50, &fromXYZD50)) {
+        return false;
+    }
+
+    skcms_TransferFunction tf[3];
+    for (int i = 0; i < 3; i++) {
+        skcms_TransferFunction inv;
+        if (profile->trc[i].table_entries == 0
+            && skcms_TransferFunction_invert(&profile->trc[i].parametric, &inv)) {
+            tf[i] = profile->trc[i].parametric;
+            continue;
+        }
+
+        float max_error;
+        // Parametric curves from skcms_ApproximateCurve() are guaranteed to be invertible.
+        if (!skcms_ApproximateCurve(&profile->trc[i], &tf[i], &max_error)) {
+            return false;
+        }
+    }
+
+    for (int i = 0; i < 3; ++i) {
+        profile->trc[i].table_entries = 0;
+        profile->trc[i].parametric = tf[i];
+    }
+
+    assert_usable_as_destination(profile);
+    return true;
+}
+
+bool skcms_MakeUsableAsDestinationWithSingleCurve(skcms_ICCProfile* profile) {
+    // Operate on a copy of profile, so we can choose the best TF for the original curves
+    skcms_ICCProfile result = *profile;
+    if (!skcms_MakeUsableAsDestination(&result)) {
+        return false;
+    }
+
+    int best_tf = 0;
+    float min_max_error = INFINITY_;
+    for (int i = 0; i < 3; i++) {
+        skcms_TransferFunction inv;
+        skcms_TransferFunction_invert(&result.trc[i].parametric, &inv);
+
+        float err = 0;
+        for (int j = 0; j < 3; ++j) {
+            err = fmaxf_(err, skcms_MaxRoundtripError(&profile->trc[j], &inv));
+        }
+        if (min_max_error > err) {
+            min_max_error = err;
+            best_tf = i;
+        }
+    }
+
+    for (int i = 0; i < 3; i++) {
+        result.trc[i].parametric = result.trc[best_tf].parametric;
+    }
+
+    *profile = result;
+    assert_usable_as_destination(profile);
+    return true;
+}
diff --git a/third_party/skcms/skcms.gni b/third_party/skcms/skcms.gni
index fbd816cf4e..2cfe2fbe68 100644
--- a/third_party/skcms/skcms.gni
+++ b/third_party/skcms/skcms.gni
@@ -4,13 +4,8 @@
 # found in the LICENSE file.
 
 skcms_sources = [
+  "skcms.c",
   "skcms.h",
   "skcms_internal.h",
-  "src/Curve.c",
-  "src/ICCProfile.c",
-  "src/LinearAlgebra.c",
-  "src/PortableMath.c",
-  "src/TransferFunction.c",
-  "src/Transform.c",
   "src/Transform_inl.h",
 ]
diff --git a/third_party/skcms/src/Curve.c b/third_party/skcms/src/Curve.c
deleted file mode 100644
index 2b99fd7bf4..0000000000
--- a/third_party/skcms/src/Curve.c
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms_internal.h"
-#include <assert.h>
-
-static float minus_1_ulp(float x) {
-    int32_t bits;
-    memcpy(&bits, &x, sizeof(bits));
-    bits = bits - 1;
-    memcpy(&x, &bits, sizeof(bits));
-    return x;
-}
-
-float skcms_eval_curve(const skcms_Curve* curve, float x) {
-    if (curve->table_entries == 0) {
-        return skcms_TransferFunction_eval(&curve->parametric, x);
-    }
-
-    float ix = fmaxf_(0, fminf_(x, 1)) * (curve->table_entries - 1);
-    int   lo = (int)            ix,
-          hi = (int)minus_1_ulp(ix + 1.0f);
-    float t = ix - (float)lo;
-
-    float l, h;
-    if (curve->table_8) {
-        l = curve->table_8[lo] * (1/255.0f);
-        h = curve->table_8[hi] * (1/255.0f);
-    } else {
-        uint16_t be_l, be_h;
-        memcpy(&be_l, curve->table_16 + 2*lo, 2);
-        memcpy(&be_h, curve->table_16 + 2*hi, 2);
-        uint16_t le_l = ((be_l << 8) | (be_l >> 8)) & 0xffff;
-        uint16_t le_h = ((be_h << 8) | (be_h >> 8)) & 0xffff;
-        l = le_l * (1/65535.0f);
-        h = le_h * (1/65535.0f);
-    }
-    return l + (h-l)*t;
-}
-
-float skcms_MaxRoundtripError(const skcms_Curve* curve, const skcms_TransferFunction* inv_tf) {
-    uint32_t N = curve->table_entries > 256 ? curve->table_entries : 256;
-    const float dx = 1.0f / (N - 1);
-    float err = 0;
-    for (uint32_t i = 0; i < N; i++) {
-        float x = i * dx,
-              y = skcms_eval_curve(curve, x);
-        err = fmaxf_(err, fabsf_(x - skcms_TransferFunction_eval(inv_tf, y)));
-    }
-    return err;
-}
-
-bool skcms_AreApproximateInverses(const skcms_Curve* curve, const skcms_TransferFunction* inv_tf) {
-    return skcms_MaxRoundtripError(curve, inv_tf) < (1/512.0f);
-}
diff --git a/third_party/skcms/src/ICCProfile.c b/third_party/skcms/src/ICCProfile.c
deleted file mode 100644
index 257e111025..0000000000
--- a/third_party/skcms/src/ICCProfile.c
+++ /dev/null
@@ -1,1052 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "../skcms_internal.h"
-#include <assert.h>
-#include <limits.h>
-#include <stdlib.h>
-#include <string.h>
-
-// Additional ICC signature values that are only used internally
-enum {
-    // File signature
-    skcms_Signature_acsp = 0x61637370,
-
-    // Tag signatures
-    skcms_Signature_rTRC = 0x72545243,
-    skcms_Signature_gTRC = 0x67545243,
-    skcms_Signature_bTRC = 0x62545243,
-    skcms_Signature_kTRC = 0x6B545243,
-
-    skcms_Signature_rXYZ = 0x7258595A,
-    skcms_Signature_gXYZ = 0x6758595A,
-    skcms_Signature_bXYZ = 0x6258595A,
-
-    skcms_Signature_A2B0 = 0x41324230,
-    skcms_Signature_A2B1 = 0x41324231,
-    skcms_Signature_mAB  = 0x6D414220,
-
-    skcms_Signature_CHAD = 0x63686164,
-
-    // Type signatures
-    skcms_Signature_curv = 0x63757276,
-    skcms_Signature_mft1 = 0x6D667431,
-    skcms_Signature_mft2 = 0x6D667432,
-    skcms_Signature_para = 0x70617261,
-    skcms_Signature_sf32 = 0x73663332,
-    // XYZ is also a PCS signature, so it's defined in skcms.h
-    // skcms_Signature_XYZ = 0x58595A20,
-};
-
-static uint16_t read_big_u16(const uint8_t* ptr) {
-    uint16_t be;
-    memcpy(&be, ptr, sizeof(be));
-#if defined(_MSC_VER)
-    return _byteswap_ushort(be);
-#else
-    return __builtin_bswap16(be);
-#endif
-}
-
-static uint32_t read_big_u32(const uint8_t* ptr) {
-    uint32_t be;
-    memcpy(&be, ptr, sizeof(be));
-#if defined(_MSC_VER)
-    return _byteswap_ulong(be);
-#else
-    return __builtin_bswap32(be);
-#endif
-}
-
-static int32_t read_big_i32(const uint8_t* ptr) {
-    return (int32_t)read_big_u32(ptr);
-}
-
-static float read_big_fixed(const uint8_t* ptr) {
-    return read_big_i32(ptr) * (1.0f / 65536.0f);
-}
-
-// Maps to an in-memory profile so that fields line up to the locations specified
-// in ICC.1:2010, section 7.2
-typedef struct {
-    uint8_t size                [ 4];
-    uint8_t cmm_type            [ 4];
-    uint8_t version             [ 4];
-    uint8_t profile_class       [ 4];
-    uint8_t data_color_space    [ 4];
-    uint8_t pcs                 [ 4];
-    uint8_t creation_date_time  [12];
-    uint8_t signature           [ 4];
-    uint8_t platform            [ 4];
-    uint8_t flags               [ 4];
-    uint8_t device_manufacturer [ 4];
-    uint8_t device_model        [ 4];
-    uint8_t device_attributes   [ 8];
-    uint8_t rendering_intent    [ 4];
-    uint8_t illuminant_X        [ 4];
-    uint8_t illuminant_Y        [ 4];
-    uint8_t illuminant_Z        [ 4];
-    uint8_t creator             [ 4];
-    uint8_t profile_id          [16];
-    uint8_t reserved            [28];
-    uint8_t tag_count           [ 4]; // Technically not part of header, but required
-} header_Layout;
-
-typedef struct {
-    uint8_t signature [4];
-    uint8_t offset    [4];
-    uint8_t size      [4];
-} tag_Layout;
-
-static const tag_Layout* get_tag_table(const skcms_ICCProfile* profile) {
-    return (const tag_Layout*)(profile->buffer + SAFE_SIZEOF(header_Layout));
-}
-
-// s15Fixed16ArrayType is technically variable sized, holding N values. However, the only valid
-// use of the type is for the CHAD tag that stores exactly nine values.
-typedef struct {
-    uint8_t type     [ 4];
-    uint8_t reserved [ 4];
-    uint8_t values   [36];
-} sf32_Layout;
-
-bool skcms_GetCHAD(const skcms_ICCProfile* profile, skcms_Matrix3x3* m) {
-    skcms_ICCTag tag;
-    if (!skcms_GetTagBySignature(profile, skcms_Signature_CHAD, &tag)) {
-        return false;
-    }
-
-    if (tag.type != skcms_Signature_sf32 || tag.size < SAFE_SIZEOF(sf32_Layout)) {
-        return false;
-    }
-
-    const sf32_Layout* sf32Tag = (const sf32_Layout*)tag.buf;
-    const uint8_t* values = sf32Tag->values;
-    for (int r = 0; r < 3; ++r)
-    for (int c = 0; c < 3; ++c, values += 4) {
-        m->vals[r][c] = read_big_fixed(values);
-    }
-    return true;
-}
-
-// XYZType is technically variable sized, holding N XYZ triples. However, the only valid uses of
-// the type are for tags/data that store exactly one triple.
-typedef struct {
-    uint8_t type     [4];
-    uint8_t reserved [4];
-    uint8_t X        [4];
-    uint8_t Y        [4];
-    uint8_t Z        [4];
-} XYZ_Layout;
-
-static bool read_tag_xyz(const skcms_ICCTag* tag, float* x, float* y, float* z) {
-    if (tag->type != skcms_Signature_XYZ || tag->size < SAFE_SIZEOF(XYZ_Layout)) {
-        return false;
-    }
-
-    const XYZ_Layout* xyzTag = (const XYZ_Layout*)tag->buf;
-
-    *x = read_big_fixed(xyzTag->X);
-    *y = read_big_fixed(xyzTag->Y);
-    *z = read_big_fixed(xyzTag->Z);
-    return true;
-}
-
-static bool read_to_XYZD50(const skcms_ICCTag* rXYZ, const skcms_ICCTag* gXYZ,
-                           const skcms_ICCTag* bXYZ, skcms_Matrix3x3* toXYZ) {
-    return read_tag_xyz(rXYZ, &toXYZ->vals[0][0], &toXYZ->vals[1][0], &toXYZ->vals[2][0]) &&
-           read_tag_xyz(gXYZ, &toXYZ->vals[0][1], &toXYZ->vals[1][1], &toXYZ->vals[2][1]) &&
-           read_tag_xyz(bXYZ, &toXYZ->vals[0][2], &toXYZ->vals[1][2], &toXYZ->vals[2][2]);
-}
-
-typedef struct {
-    uint8_t type          [4];
-    uint8_t reserved_a    [4];
-    uint8_t function_type [2];
-    uint8_t reserved_b    [2];
-    uint8_t parameters    [ ];  // 1, 3, 4, 5, or 7 s15.16 parameters, depending on function_type
-} para_Layout;
-
-static bool read_curve_para(const uint8_t* buf, uint32_t size,
-                            skcms_Curve* curve, uint32_t* curve_size) {
-    if (size < SAFE_SIZEOF(para_Layout)) {
-        return false;
-    }
-
-    const para_Layout* paraTag = (const para_Layout*)buf;
-
-    enum { kG = 0, kGAB = 1, kGABC = 2, kGABCD = 3, kGABCDEF = 4 };
-    uint16_t function_type = read_big_u16(paraTag->function_type);
-    if (function_type > kGABCDEF) {
-        return false;
-    }
-
-    static const uint32_t curve_bytes[] = { 4, 12, 16, 20, 28 };
-    if (size < SAFE_SIZEOF(para_Layout) + curve_bytes[function_type]) {
-        return false;
-    }
-
-    if (curve_size) {
-        *curve_size = SAFE_SIZEOF(para_Layout) + curve_bytes[function_type];
-    }
-
-    curve->table_entries = 0;
-    curve->parametric.a  = 1.0f;
-    curve->parametric.b  = 0.0f;
-    curve->parametric.c  = 0.0f;
-    curve->parametric.d  = 0.0f;
-    curve->parametric.e  = 0.0f;
-    curve->parametric.f  = 0.0f;
-    curve->parametric.g  = read_big_fixed(paraTag->parameters);
-
-    switch (function_type) {
-        case kGAB:
-            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
-            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
-            if (curve->parametric.a == 0) {
-                return false;
-            }
-            curve->parametric.d = -curve->parametric.b / curve->parametric.a;
-            break;
-        case kGABC:
-            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
-            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
-            curve->parametric.e = read_big_fixed(paraTag->parameters + 12);
-            if (curve->parametric.a == 0) {
-                return false;
-            }
-            curve->parametric.d = -curve->parametric.b / curve->parametric.a;
-            curve->parametric.f = curve->parametric.e;
-            break;
-        case kGABCD:
-            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
-            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
-            curve->parametric.c = read_big_fixed(paraTag->parameters + 12);
-            curve->parametric.d = read_big_fixed(paraTag->parameters + 16);
-            break;
-        case kGABCDEF:
-            curve->parametric.a = read_big_fixed(paraTag->parameters + 4);
-            curve->parametric.b = read_big_fixed(paraTag->parameters + 8);
-            curve->parametric.c = read_big_fixed(paraTag->parameters + 12);
-            curve->parametric.d = read_big_fixed(paraTag->parameters + 16);
-            curve->parametric.e = read_big_fixed(paraTag->parameters + 20);
-            curve->parametric.f = read_big_fixed(paraTag->parameters + 24);
-            break;
-    }
-    return skcms_TransferFunction_isValid(&curve->parametric);
-}
-
-typedef struct {
-    uint8_t type          [4];
-    uint8_t reserved      [4];
-    uint8_t value_count   [4];
-    uint8_t parameters    [ ];  // value_count parameters (8.8 if 1, uint16 (n*65535) if > 1)
-} curv_Layout;
-
-static bool read_curve_curv(const uint8_t* buf, uint32_t size,
-                            skcms_Curve* curve, uint32_t* curve_size) {
-    if (size < SAFE_SIZEOF(curv_Layout)) {
-        return false;
-    }
-
-    const curv_Layout* curvTag = (const curv_Layout*)buf;
-
-    uint32_t value_count = read_big_u32(curvTag->value_count);
-    if (size < SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t)) {
-        return false;
-    }
-
-    if (curve_size) {
-        *curve_size = SAFE_SIZEOF(curv_Layout) + value_count * SAFE_SIZEOF(uint16_t);
-    }
-
-    if (value_count < 2) {
-        curve->table_entries = 0;
-        curve->parametric.a  = 1.0f;
-        curve->parametric.b  = 0.0f;
-        curve->parametric.c  = 0.0f;
-        curve->parametric.d  = 0.0f;
-        curve->parametric.e  = 0.0f;
-        curve->parametric.f  = 0.0f;
-        if (value_count == 0) {
-            // Empty tables are a shorthand for an identity curve
-            curve->parametric.g = 1.0f;
-        } else {
-            // Single entry tables are a shorthand for simple gamma
-            curve->parametric.g = read_big_u16(curvTag->parameters) * (1.0f / 256.0f);
-        }
-    } else {
-        curve->table_8       = NULL;
-        curve->table_16      = curvTag->parameters;
-        curve->table_entries = value_count;
-    }
-
-    return true;
-}
-
-// Parses both curveType and parametricCurveType data. Ensures that at most 'size' bytes are read.
-// If curve_size is not NULL, writes the number of bytes used by the curve in (*curve_size).
-static bool read_curve(const uint8_t* buf, uint32_t size,
-                       skcms_Curve* curve, uint32_t* curve_size) {
-    if (!buf || size < 4 || !curve) {
-        return false;
-    }
-
-    uint32_t type = read_big_u32(buf);
-    if (type == skcms_Signature_para) {
-        return read_curve_para(buf, size, curve, curve_size);
-    } else if (type == skcms_Signature_curv) {
-        return read_curve_curv(buf, size, curve, curve_size);
-    }
-
-    return false;
-}
-
-// mft1 and mft2 share a large chunk of data
-typedef struct {
-    uint8_t type                 [ 4];
-    uint8_t reserved_a           [ 4];
-    uint8_t input_channels       [ 1];
-    uint8_t output_channels      [ 1];
-    uint8_t grid_points          [ 1];
-    uint8_t reserved_b           [ 1];
-    uint8_t matrix               [36];
-} mft_CommonLayout;
-
-typedef struct {
-    mft_CommonLayout common      [ 1];
-
-    uint8_t tables               [  ];
-} mft1_Layout;
-
-typedef struct {
-    mft_CommonLayout common      [ 1];
-
-    uint8_t input_table_entries  [ 2];
-    uint8_t output_table_entries [ 2];
-    uint8_t tables               [  ];
-} mft2_Layout;
-
-static bool read_mft_common(const mft_CommonLayout* mftTag, skcms_A2B* a2b) {
-    // MFT matrices are applied before the first set of curves, but must be identity unless the
-    // input is PCSXYZ. We don't support PCSXYZ profiles, so we ignore this matrix. Note that the
-    // matrix in skcms_A2B is applied later in the pipe, so supporting this would require another
-    // field/flag.
-    a2b->matrix_channels = 0;
-
-    a2b->input_channels  = mftTag->input_channels[0];
-    a2b->output_channels = mftTag->output_channels[0];
-
-    // We require exactly three (ie XYZ/Lab/RGB) output channels
-    if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) {
-        return false;
-    }
-    // We require at least one, and no more than four (ie CMYK) input channels
-    if (a2b->input_channels < 1 || a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) {
-        return false;
-    }
-
-    for (uint32_t i = 0; i < a2b->input_channels; ++i) {
-        a2b->grid_points[i] = mftTag->grid_points[0];
-    }
-    // The grid only makes sense with at least two points along each axis
-    if (a2b->grid_points[0] < 2) {
-        return false;
-    }
-
-    return true;
-}
-
-static bool init_a2b_tables(const uint8_t* table_base, uint64_t max_tables_len, uint32_t byte_width,
-                            uint32_t input_table_entries, uint32_t output_table_entries,
-                            skcms_A2B* a2b) {
-    // byte_width is 1 or 2, [input|output]_table_entries are in [2, 4096], so no overflow
-    uint32_t byte_len_per_input_table  = input_table_entries * byte_width;
-    uint32_t byte_len_per_output_table = output_table_entries * byte_width;
-
-    // [input|output]_channels are <= 4, so still no overflow
-    uint32_t byte_len_all_input_tables  = a2b->input_channels * byte_len_per_input_table;
-    uint32_t byte_len_all_output_tables = a2b->output_channels * byte_len_per_output_table;
-
-    uint64_t grid_size = a2b->output_channels * byte_width;
-    for (uint32_t axis = 0; axis < a2b->input_channels; ++axis) {
-        grid_size *= a2b->grid_points[axis];
-    }
-
-    if (max_tables_len < byte_len_all_input_tables + grid_size + byte_len_all_output_tables) {
-        return false;
-    }
-
-    for (uint32_t i = 0; i < a2b->input_channels; ++i) {
-        a2b->input_curves[i].table_entries = input_table_entries;
-        if (byte_width == 1) {
-            a2b->input_curves[i].table_8  = table_base + i * byte_len_per_input_table;
-            a2b->input_curves[i].table_16 = NULL;
-        } else {
-            a2b->input_curves[i].table_8  = NULL;
-            a2b->input_curves[i].table_16 = table_base + i * byte_len_per_input_table;
-        }
-    }
-
-    if (byte_width == 1) {
-        a2b->grid_8  = table_base + byte_len_all_input_tables;
-        a2b->grid_16 = NULL;
-    } else {
-        a2b->grid_8  = NULL;
-        a2b->grid_16 = table_base + byte_len_all_input_tables;
-    }
-
-    const uint8_t* output_table_base = table_base + byte_len_all_input_tables + grid_size;
-    for (uint32_t i = 0; i < a2b->output_channels; ++i) {
-        a2b->output_curves[i].table_entries = output_table_entries;
-        if (byte_width == 1) {
-            a2b->output_curves[i].table_8  = output_table_base + i * byte_len_per_output_table;
-            a2b->output_curves[i].table_16 = NULL;
-        } else {
-            a2b->output_curves[i].table_8  = NULL;
-            a2b->output_curves[i].table_16 = output_table_base + i * byte_len_per_output_table;
-        }
-    }
-
-    return true;
-}
-
-static bool read_tag_mft1(const skcms_ICCTag* tag, skcms_A2B* a2b) {
-    if (tag->size < SAFE_SIZEOF(mft1_Layout)) {
-        return false;
-    }
-
-    const mft1_Layout* mftTag = (const mft1_Layout*)tag->buf;
-    if (!read_mft_common(mftTag->common, a2b)) {
-        return false;
-    }
-
-    uint32_t input_table_entries  = 256;
-    uint32_t output_table_entries = 256;
-
-    return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft1_Layout), 1,
-                           input_table_entries, output_table_entries, a2b);
-}
-
-static bool read_tag_mft2(const skcms_ICCTag* tag, skcms_A2B* a2b) {
-    if (tag->size < SAFE_SIZEOF(mft2_Layout)) {
-        return false;
-    }
-
-    const mft2_Layout* mftTag = (const mft2_Layout*)tag->buf;
-    if (!read_mft_common(mftTag->common, a2b)) {
-        return false;
-    }
-
-    uint32_t input_table_entries = read_big_u16(mftTag->input_table_entries);
-    uint32_t output_table_entries = read_big_u16(mftTag->output_table_entries);
-
-    // ICC spec mandates that 2 <= table_entries <= 4096
-    if (input_table_entries < 2 || input_table_entries > 4096 ||
-        output_table_entries < 2 || output_table_entries > 4096) {
-        return false;
-    }
-
-    return init_a2b_tables(mftTag->tables, tag->size - SAFE_SIZEOF(mft2_Layout), 2,
-                           input_table_entries, output_table_entries, a2b);
-}
-
-static bool read_curves(const uint8_t* buf, uint32_t size, uint32_t curve_offset,
-                        uint32_t num_curves, skcms_Curve* curves) {
-    for (uint32_t i = 0; i < num_curves; ++i) {
-        if (curve_offset > size) {
-            return false;
-        }
-
-        uint32_t curve_bytes;
-        if (!read_curve(buf + curve_offset, size - curve_offset, &curves[i], &curve_bytes)) {
-            return false;
-        }
-
-        if (curve_bytes > UINT32_MAX - 3) {
-            return false;
-        }
-        curve_bytes = (curve_bytes + 3) & ~3U;
-
-        uint64_t new_offset_64 = (uint64_t)curve_offset + curve_bytes;
-        curve_offset = (uint32_t)new_offset_64;
-        if (new_offset_64 != curve_offset) {
-            return false;
-        }
-    }
-
-    return true;
-}
-
-typedef struct {
-    uint8_t type                 [ 4];
-    uint8_t reserved_a           [ 4];
-    uint8_t input_channels       [ 1];
-    uint8_t output_channels      [ 1];
-    uint8_t reserved_b           [ 2];
-    uint8_t b_curve_offset       [ 4];
-    uint8_t matrix_offset        [ 4];
-    uint8_t m_curve_offset       [ 4];
-    uint8_t clut_offset          [ 4];
-    uint8_t a_curve_offset       [ 4];
-} mAB_Layout;
-
-typedef struct {
-    uint8_t grid_points          [16];
-    uint8_t grid_byte_width      [ 1];
-    uint8_t reserved             [ 3];
-    uint8_t data                 [  ];
-} mABCLUT_Layout;
-
-static bool read_tag_mab(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) {
-    if (tag->size < SAFE_SIZEOF(mAB_Layout)) {
-        return false;
-    }
-
-    const mAB_Layout* mABTag = (const mAB_Layout*)tag->buf;
-
-    a2b->input_channels  = mABTag->input_channels[0];
-    a2b->output_channels = mABTag->output_channels[0];
-
-    // We require exactly three (ie XYZ/Lab/RGB) output channels
-    if (a2b->output_channels != ARRAY_COUNT(a2b->output_curves)) {
-        return false;
-    }
-    // We require no more than four (ie CMYK) input channels
-    if (a2b->input_channels > ARRAY_COUNT(a2b->input_curves)) {
-        return false;
-    }
-
-    uint32_t b_curve_offset = read_big_u32(mABTag->b_curve_offset);
-    uint32_t matrix_offset  = read_big_u32(mABTag->matrix_offset);
-    uint32_t m_curve_offset = read_big_u32(mABTag->m_curve_offset);
-    uint32_t clut_offset    = read_big_u32(mABTag->clut_offset);
-    uint32_t a_curve_offset = read_big_u32(mABTag->a_curve_offset);
-
-    // "B" curves must be present
-    if (0 == b_curve_offset) {
-        return false;
-    }
-
-    if (!read_curves(tag->buf, tag->size, b_curve_offset, a2b->output_channels,
-                     a2b->output_curves)) {
-        return false;
-    }
-
-    // "M" curves and Matrix must be used together
-    if (0 != m_curve_offset) {
-        if (0 == matrix_offset) {
-            return false;
-        }
-        a2b->matrix_channels = a2b->output_channels;
-        if (!read_curves(tag->buf, tag->size, m_curve_offset, a2b->matrix_channels,
-                         a2b->matrix_curves)) {
-            return false;
-        }
-
-        // Read matrix, which is stored as a row-major 3x3, followed by the fourth column
-        if (tag->size < matrix_offset + 12 * SAFE_SIZEOF(uint32_t)) {
-            return false;
-        }
-        float encoding_factor = pcs_is_xyz ? 65535 / 32768.0f : 1.0f;
-        const uint8_t* mtx_buf = tag->buf + matrix_offset;
-        a2b->matrix.vals[0][0] = encoding_factor * read_big_fixed(mtx_buf + 0);
-        a2b->matrix.vals[0][1] = encoding_factor * read_big_fixed(mtx_buf + 4);
-        a2b->matrix.vals[0][2] = encoding_factor * read_big_fixed(mtx_buf + 8);
-        a2b->matrix.vals[1][0] = encoding_factor * read_big_fixed(mtx_buf + 12);
-        a2b->matrix.vals[1][1] = encoding_factor * read_big_fixed(mtx_buf + 16);
-        a2b->matrix.vals[1][2] = encoding_factor * read_big_fixed(mtx_buf + 20);
-        a2b->matrix.vals[2][0] = encoding_factor * read_big_fixed(mtx_buf + 24);
-        a2b->matrix.vals[2][1] = encoding_factor * read_big_fixed(mtx_buf + 28);
-        a2b->matrix.vals[2][2] = encoding_factor * read_big_fixed(mtx_buf + 32);
-        a2b->matrix.vals[0][3] = encoding_factor * read_big_fixed(mtx_buf + 36);
-        a2b->matrix.vals[1][3] = encoding_factor * read_big_fixed(mtx_buf + 40);
-        a2b->matrix.vals[2][3] = encoding_factor * read_big_fixed(mtx_buf + 44);
-    } else {
-        if (0 != matrix_offset) {
-            return false;
-        }
-        a2b->matrix_channels = 0;
-    }
-
-    // "A" curves and CLUT must be used together
-    if (0 != a_curve_offset) {
-        if (0 == clut_offset) {
-            return false;
-        }
-        if (!read_curves(tag->buf, tag->size, a_curve_offset, a2b->input_channels,
-                         a2b->input_curves)) {
-            return false;
-        }
-
-        if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout)) {
-            return false;
-        }
-        const mABCLUT_Layout* clut = (const mABCLUT_Layout*)(tag->buf + clut_offset);
-
-        if (clut->grid_byte_width[0] == 1) {
-            a2b->grid_8  = clut->data;
-            a2b->grid_16 = NULL;
-        } else if (clut->grid_byte_width[0] == 2) {
-            a2b->grid_8  = NULL;
-            a2b->grid_16 = clut->data;
-        } else {
-            return false;
-        }
-
-        uint64_t grid_size = a2b->output_channels * clut->grid_byte_width[0];
-        for (uint32_t i = 0; i < a2b->input_channels; ++i) {
-            a2b->grid_points[i] = clut->grid_points[i];
-            // The grid only makes sense with at least two points along each axis
-            if (a2b->grid_points[i] < 2) {
-                return false;
-            }
-            grid_size *= a2b->grid_points[i];
-        }
-        if (tag->size < clut_offset + SAFE_SIZEOF(mABCLUT_Layout) + grid_size) {
-            return false;
-        }
-    } else {
-        if (0 != clut_offset) {
-            return false;
-        }
-
-        // If there is no CLUT, the number of input and output channels must match
-        if (a2b->input_channels != a2b->output_channels) {
-            return false;
-        }
-
-        // Zero out the number of input channels to signal that we're skipping this stage
-        a2b->input_channels = 0;
-    }
-
-    return true;
-}
-
-static bool read_a2b(const skcms_ICCTag* tag, skcms_A2B* a2b, bool pcs_is_xyz) {
-    bool ok = false;
-    if (tag->type == skcms_Signature_mft1) {
-        ok = read_tag_mft1(tag, a2b);
-    } else if (tag->type == skcms_Signature_mft2) {
-        ok = read_tag_mft2(tag, a2b);
-    } else if (tag->type == skcms_Signature_mAB) {
-        ok = read_tag_mab(tag, a2b, pcs_is_xyz);
-    }
-    if (!ok) {
-        return false;
-    }
-
-    // Detect and canonicalize identity tables.
-    skcms_Curve* curves[] = {
-        a2b->input_channels  > 0 ? a2b->input_curves  + 0 : NULL,
-        a2b->input_channels  > 1 ? a2b->input_curves  + 1 : NULL,
-        a2b->input_channels  > 2 ? a2b->input_curves  + 2 : NULL,
-        a2b->input_channels  > 3 ? a2b->input_curves  + 3 : NULL,
-        a2b->matrix_channels > 0 ? a2b->matrix_curves + 0 : NULL,
-        a2b->matrix_channels > 1 ? a2b->matrix_curves + 1 : NULL,
-        a2b->matrix_channels > 2 ? a2b->matrix_curves + 2 : NULL,
-        a2b->output_channels > 0 ? a2b->output_curves + 0 : NULL,
-        a2b->output_channels > 1 ? a2b->output_curves + 1 : NULL,
-        a2b->output_channels > 2 ? a2b->output_curves + 2 : NULL,
-    };
-
-    for (int i = 0; i < ARRAY_COUNT(curves); i++) {
-        skcms_Curve* curve = curves[i];
-
-        if (curve && curve->table_entries && curve->table_entries <= (uint32_t)INT_MAX) {
-            int N = (int)curve->table_entries;
-
-            float c,d,f;
-            if (N == skcms_fit_linear(curve, N, 1.0f/(2*N), &c,&d,&f)
-                && c == 1.0f
-                && f == 0.0f) {
-                curve->table_entries = 0;
-                curve->table_8       = NULL;
-                curve->table_16      = NULL;
-                curve->parametric    = (skcms_TransferFunction){1,1,0,0,0,0,0};
-            }
-        }
-    }
-
-    return true;
-}
-
-void skcms_GetTagByIndex(const skcms_ICCProfile* profile, uint32_t idx, skcms_ICCTag* tag) {
-    if (!profile || !profile->buffer || !tag) { return; }
-    if (idx > profile->tag_count) { return; }
-    const tag_Layout* tags = get_tag_table(profile);
-    tag->signature = read_big_u32(tags[idx].signature);
-    tag->size      = read_big_u32(tags[idx].size);
-    tag->buf       = read_big_u32(tags[idx].offset) + profile->buffer;
-    tag->type      = read_big_u32(tag->buf);
-}
-
-bool skcms_GetTagBySignature(const skcms_ICCProfile* profile, uint32_t sig, skcms_ICCTag* tag) {
-    if (!profile || !profile->buffer || !tag) { return false; }
-    const tag_Layout* tags = get_tag_table(profile);
-    for (uint32_t i = 0; i < profile->tag_count; ++i) {
-        if (read_big_u32(tags[i].signature) == sig) {
-            tag->signature = sig;
-            tag->size      = read_big_u32(tags[i].size);
-            tag->buf       = read_big_u32(tags[i].offset) + profile->buffer;
-            tag->type      = read_big_u32(tag->buf);
-            return true;
-        }
-    }
-    return false;
-}
-
-static bool usable_as_src(const skcms_ICCProfile* profile) {
-    return profile->has_A2B
-       || (profile->has_trc && profile->has_toXYZD50);
-}
-
-bool skcms_Parse(const void* buf, size_t len, skcms_ICCProfile* profile) {
-    assert(SAFE_SIZEOF(header_Layout) == 132);
-
-    if (!profile) {
-        return false;
-    }
-    memset(profile, 0, SAFE_SIZEOF(*profile));
-
-    if (len < SAFE_SIZEOF(header_Layout)) {
-        return false;
-    }
-
-    // Byte-swap all header fields
-    const header_Layout* header = buf;
-    profile->buffer              = buf;
-    profile->size                = read_big_u32(header->size);
-    uint32_t version             = read_big_u32(header->version);
-    profile->data_color_space    = read_big_u32(header->data_color_space);
-    profile->pcs                 = read_big_u32(header->pcs);
-    uint32_t signature           = read_big_u32(header->signature);
-    float illuminant_X           = read_big_fixed(header->illuminant_X);
-    float illuminant_Y           = read_big_fixed(header->illuminant_Y);
-    float illuminant_Z           = read_big_fixed(header->illuminant_Z);
-    profile->tag_count           = read_big_u32(header->tag_count);
-
-    // Validate signature, size (smaller than buffer, large enough to hold tag table),
-    // and major version
-    uint64_t tag_table_size = profile->tag_count * SAFE_SIZEOF(tag_Layout);
-    if (signature != skcms_Signature_acsp ||
-        profile->size > len ||
-        profile->size < SAFE_SIZEOF(header_Layout) + tag_table_size ||
-        (version >> 24) > 4) {
-        return false;
-    }
-
-    // Validate that illuminant is D50 white
-    if (fabsf_(illuminant_X - 0.9642f) > 0.0100f ||
-        fabsf_(illuminant_Y - 1.0000f) > 0.0100f ||
-        fabsf_(illuminant_Z - 0.8249f) > 0.0100f) {
-        return false;
-    }
-
-    // Validate that all tag entries have sane offset + size
-    const tag_Layout* tags = get_tag_table(profile);
-    for (uint32_t i = 0; i < profile->tag_count; ++i) {
-        uint32_t tag_offset = read_big_u32(tags[i].offset);
-        uint32_t tag_size   = read_big_u32(tags[i].size);
-        uint64_t tag_end    = (uint64_t)tag_offset + (uint64_t)tag_size;
-        if (tag_size < 4 || tag_end > profile->size) {
-            return false;
-        }
-    }
-
-    if (profile->pcs != skcms_Signature_XYZ && profile->pcs != skcms_Signature_Lab) {
-        return false;
-    }
-
-    bool pcs_is_xyz = profile->pcs == skcms_Signature_XYZ;
-
-    // Pre-parse commonly used tags.
-    skcms_ICCTag kTRC;
-    if (profile->data_color_space == skcms_Signature_Gray &&
-        skcms_GetTagBySignature(profile, skcms_Signature_kTRC, &kTRC)) {
-        if (!read_curve(kTRC.buf, kTRC.size, &profile->trc[0], NULL)) {
-            // Malformed tag
-            return false;
-        }
-        profile->trc[1] = profile->trc[0];
-        profile->trc[2] = profile->trc[0];
-        profile->has_trc = true;
-
-        if (pcs_is_xyz) {
-            profile->toXYZD50.vals[0][0] = illuminant_X;
-            profile->toXYZD50.vals[1][1] = illuminant_Y;
-            profile->toXYZD50.vals[2][2] = illuminant_Z;
-            profile->has_toXYZD50 = true;
-        }
-    } else {
-        skcms_ICCTag rTRC, gTRC, bTRC;
-        if (skcms_GetTagBySignature(profile, skcms_Signature_rTRC, &rTRC) &&
-            skcms_GetTagBySignature(profile, skcms_Signature_gTRC, &gTRC) &&
-            skcms_GetTagBySignature(profile, skcms_Signature_bTRC, &bTRC)) {
-            if (!read_curve(rTRC.buf, rTRC.size, &profile->trc[0], NULL) ||
-                !read_curve(gTRC.buf, gTRC.size, &profile->trc[1], NULL) ||
-                !read_curve(bTRC.buf, bTRC.size, &profile->trc[2], NULL)) {
-                // Malformed TRC tags
-                return false;
-            }
-            profile->has_trc = true;
-        }
-
-        skcms_ICCTag rXYZ, gXYZ, bXYZ;
-        if (skcms_GetTagBySignature(profile, skcms_Signature_rXYZ, &rXYZ) &&
-            skcms_GetTagBySignature(profile, skcms_Signature_gXYZ, &gXYZ) &&
-            skcms_GetTagBySignature(profile, skcms_Signature_bXYZ, &bXYZ)) {
-            if (!read_to_XYZD50(&rXYZ, &gXYZ, &bXYZ, &profile->toXYZD50)) {
-                // Malformed XYZ tags
-                return false;
-            }
-            profile->has_toXYZD50 = true;
-        }
-    }
-
-    skcms_ICCTag a2b_tag;
-
-    // For now, we're preferring A2B0, like Skia does and the ICC spec tells us to.
-    // TODO: prefer A2B1 (relative colormetric) over A2B0 (perceptual)?
-    // This breaks with the ICC spec, but we think it's a good idea, given that TRC curves
-    // and all our known users are thinking exclusively in terms of relative colormetric.
-    const uint32_t sigs[] = { skcms_Signature_A2B0, skcms_Signature_A2B1 };
-    for (int i = 0; i < ARRAY_COUNT(sigs); i++) {
-        if (skcms_GetTagBySignature(profile, sigs[i], &a2b_tag)) {
-            if (!read_a2b(&a2b_tag, &profile->A2B, pcs_is_xyz)) {
-                // Malformed A2B tag
-                return false;
-            }
-            profile->has_A2B = true;
-            break;
-        }
-    }
-
-    return usable_as_src(profile);
-}
-
-
-const skcms_ICCProfile* skcms_sRGB_profile() {
-    static const skcms_ICCProfile sRGB_profile = {
-        // These fields are moot when not a skcms_Parse()'d profile.
-        .buffer    = NULL,
-        .size      =    0,
-        .tag_count =    0,
-
-        // We choose to represent sRGB with its canonical transfer function,
-        // and with its canonical XYZD50 gamut matrix.
-        .data_color_space = skcms_Signature_RGB,
-        .pcs              = skcms_Signature_XYZ,
-        .has_trc      = true,
-        .has_toXYZD50 = true,
-        .has_A2B      = false,
-
-        .trc = {
-            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
-            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
-            {{0, {2.4f, (float)(1/1.055), (float)(0.055/1.055), (float)(1/12.92), 0.04045f, 0, 0 }}},
-        },
-
-        .toXYZD50 = {{
-            { 0.436065674f, 0.385147095f, 0.143066406f },
-            { 0.222488403f, 0.716873169f, 0.060607910f },
-            { 0.013916016f, 0.097076416f, 0.714096069f },
-        }},
-    };
-    return &sRGB_profile;
-}
-
-const skcms_ICCProfile* skcms_XYZD50_profile() {
-    static const skcms_ICCProfile XYZD50_profile = {
-        .buffer           = NULL,
-        .size             = 0,
-        .tag_count        = 0,
-
-        .data_color_space = skcms_Signature_RGB,
-        .pcs              = skcms_Signature_XYZ,
-        .has_trc          = true,
-        .has_toXYZD50     = true,
-        .has_A2B          = false,
-
-        .trc = {
-            {{0, {1,1,0,0,0,0,0}}},
-            {{0, {1,1,0,0,0,0,0}}},
-            {{0, {1,1,0,0,0,0,0}}},
-        },
-
-        .toXYZD50 = {{
-            {1,0,0},
-            {0,1,0},
-            {0,0,1},
-        }},
-    };
-
-    return &XYZD50_profile;
-}
-
-const skcms_TransferFunction* skcms_sRGB_TransferFunction() {
-    return &skcms_sRGB_profile()->trc[0].parametric;
-}
-
-const skcms_TransferFunction* skcms_sRGB_Inverse_TransferFunction() {
-    static const skcms_TransferFunction sRGB_inv =
-        { (float)(1/2.4), 1.137119f, 0, 12.92f, 0.0031308f, -0.055f, 0 };
-    return &sRGB_inv;
-}
-
-const skcms_TransferFunction* skcms_Identity_TransferFunction() {
-    static const skcms_TransferFunction identity = {1,1,0,0,0,0,0};
-    return &identity;
-}
-
-const uint8_t skcms_252_random_bytes[] = {
-    8, 179, 128, 204, 253, 38, 134, 184, 68, 102, 32, 138, 99, 39, 169, 215,
-    119, 26, 3, 223, 95, 239, 52, 132, 114, 74, 81, 234, 97, 116, 244, 205, 30,
-    154, 173, 12, 51, 159, 122, 153, 61, 226, 236, 178, 229, 55, 181, 220, 191,
-    194, 160, 126, 168, 82, 131, 18, 180, 245, 163, 22, 246, 69, 235, 252, 57,
-    108, 14, 6, 152, 240, 255, 171, 242, 20, 227, 177, 238, 96, 85, 16, 211,
-    70, 200, 149, 155, 146, 127, 145, 100, 151, 109, 19, 165, 208, 195, 164,
-    137, 254, 182, 248, 64, 201, 45, 209, 5, 147, 207, 210, 113, 162, 83, 225,
-    9, 31, 15, 231, 115, 37, 58, 53, 24, 49, 197, 56, 120, 172, 48, 21, 214,
-    129, 111, 11, 50, 187, 196, 34, 60, 103, 71, 144, 47, 203, 77, 80, 232,
-    140, 222, 250, 206, 166, 247, 139, 249, 221, 72, 106, 27, 199, 117, 54,
-    219, 135, 118, 40, 79, 41, 251, 46, 93, 212, 92, 233, 148, 28, 121, 63,
-    123, 158, 105, 59, 29, 42, 143, 23, 0, 107, 176, 87, 104, 183, 156, 193,
-    189, 90, 188, 65, 190, 17, 198, 7, 186, 161, 1, 124, 78, 125, 170, 133,
-    174, 218, 67, 157, 75, 101, 89, 217, 62, 33, 141, 228, 25, 35, 91, 230, 4,
-    2, 13, 73, 86, 167, 237, 84, 243, 44, 185, 66, 130, 110, 150, 142, 216, 88,
-    112, 36, 224, 136, 202, 76, 94, 98, 175, 213
-};
-
-bool skcms_ApproximatelyEqualProfiles(const skcms_ICCProfile* A, const skcms_ICCProfile* B) {
-    // For now this is the essentially the same strategy we use in test_only.c
-    // for our skcms_Transform() smoke tests:
-    //    1) transform A to XYZD50
-    //    2) transform B to XYZD50
-    //    3) return true if they're similar enough
-    // Our current criterion in 3) is maximum 1 bit error per XYZD50 byte.
-
-    // Here are 252 of a random shuffle of all possible bytes.
-    // 252 is evenly divisible by 3 and 4.  Only 192, 10, 241, and 43 are missing.
-
-    if (A->data_color_space != B->data_color_space) {
-        return false;
-    }
-
-    // Interpret as RGB_888 if data color space is RGB or GRAY, RGBA_8888 if CMYK.
-    skcms_PixelFormat fmt = skcms_PixelFormat_RGB_888;
-    size_t npixels = 84;
-    if (A->data_color_space == skcms_Signature_CMYK) {
-        fmt = skcms_PixelFormat_RGBA_8888;
-        npixels = 63;
-    }
-
-    uint8_t dstA[252],
-            dstB[252];
-    if (!skcms_Transform(
-                skcms_252_random_bytes,     fmt, skcms_AlphaFormat_Unpremul, A,
-                dstA, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(),
-                npixels)) {
-        return false;
-    }
-    if (!skcms_Transform(
-                skcms_252_random_bytes,     fmt, skcms_AlphaFormat_Unpremul, B,
-                dstB, skcms_PixelFormat_RGB_888, skcms_AlphaFormat_Unpremul, skcms_XYZD50_profile(),
-                npixels)) {
-        return false;
-    }
-
-    for (size_t i = 0; i < 252; i++) {
-        if (abs((int)dstA[i] - (int)dstB[i]) > 1) {
-            return false;
-        }
-    }
-    return true;
-}
-
-bool skcms_TRCs_AreApproximateInverse(const skcms_ICCProfile* profile,
-                                      const skcms_TransferFunction* inv_tf) {
-    if (!profile || !profile->has_trc) {
-        return false;
-    }
-
-    return skcms_AreApproximateInverses(&profile->trc[0], inv_tf) &&
-           skcms_AreApproximateInverses(&profile->trc[1], inv_tf) &&
-           skcms_AreApproximateInverses(&profile->trc[2], inv_tf);
-}
-
-static bool is_zero_to_one(float x) {
-    return 0 <= x && x <= 1;
-}
-
-bool skcms_PrimariesToXYZD50(float rx, float ry,
-                             float gx, float gy,
-                             float bx, float by,
-                             float wx, float wy,
-                             skcms_Matrix3x3* toXYZD50) {
-    if (!is_zero_to_one(rx) || !is_zero_to_one(ry) ||
-        !is_zero_to_one(gx) || !is_zero_to_one(gy) ||
-        !is_zero_to_one(bx) || !is_zero_to_one(by) ||
-        !is_zero_to_one(wx) || !is_zero_to_one(wy) ||
-        !toXYZD50) {
-        return false;
-    }
-
-    // First, we need to convert xy values (primaries) to XYZ.
-    skcms_Matrix3x3 primaries = {{
-        { rx, gx, bx },
-        { ry, gy, by },
-        { 1 - rx - ry, 1 - gx - gy, 1 - bx - by },
-    }};
-    skcms_Matrix3x3 primaries_inv;
-    if (!skcms_Matrix3x3_invert(&primaries, &primaries_inv)) {
-        return false;
-    }
-
-    // Assumes that Y is 1.0f.
-    skcms_Vector3 wXYZ = { { wx / wy, 1, (1 - wx - wy) / wy } };
-    skcms_Vector3 XYZ = skcms_MV_mul(&primaries_inv, &wXYZ);
-
-    skcms_Matrix3x3 toXYZ = {{
-        { XYZ.vals[0],           0,           0 },
-        {           0, XYZ.vals[1],           0 },
-        {           0,           0, XYZ.vals[2] },
-    }};
-    toXYZ = skcms_Matrix3x3_concat(&primaries, &toXYZ);
-
-    // Now convert toXYZ matrix to toXYZD50.
-    skcms_Vector3 wXYZD50 = { { 0.96422f, 1.0f, 0.82521f } };
-
-    // Calculate the chromatic adaptation matrix.  We will use the Bradford method, thus
-    // the matrices below.  The Bradford method is used by Adobe and is widely considered
-    // to be the best.
-    skcms_Matrix3x3 xyz_to_lms = {{
-        {  0.8951f,  0.2664f, -0.1614f },
-        { -0.7502f,  1.7135f,  0.0367f },
-        {  0.0389f, -0.0685f,  1.0296f },
-    }};
-    skcms_Matrix3x3 lms_to_xyz = {{
-        {  0.9869929f, -0.1470543f, 0.1599627f },
-        {  0.4323053f,  0.5183603f, 0.0492912f },
-        { -0.0085287f,  0.0400428f, 0.9684867f },
-    }};
-
-    skcms_Vector3 srcCone = skcms_MV_mul(&xyz_to_lms, &wXYZ);
-    skcms_Vector3 dstCone = skcms_MV_mul(&xyz_to_lms, &wXYZD50);
-
-    skcms_Matrix3x3 DXtoD50 = {{
-        { dstCone.vals[0] / srcCone.vals[0], 0, 0 },
-        { 0, dstCone.vals[1] / srcCone.vals[1], 0 },
-        { 0, 0, dstCone.vals[2] / srcCone.vals[2] },
-    }};
-    DXtoD50 = skcms_Matrix3x3_concat(&DXtoD50, &xyz_to_lms);
-    DXtoD50 = skcms_Matrix3x3_concat(&lms_to_xyz, &DXtoD50);
-
-    *toXYZD50 = skcms_Matrix3x3_concat(&DXtoD50, &toXYZ);
-    return true;
-}
diff --git a/third_party/skcms/src/LinearAlgebra.c b/third_party/skcms/src/LinearAlgebra.c
deleted file mode 100644
index 1cd8b3cb32..0000000000
--- a/third_party/skcms/src/LinearAlgebra.c
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "../skcms_internal.h"
-#include <float.h>
-
-bool skcms_Matrix3x3_invert(const skcms_Matrix3x3* src, skcms_Matrix3x3* dst) {
-    double a00 = src->vals[0][0],
-           a01 = src->vals[1][0],
-           a02 = src->vals[2][0],
-           a10 = src->vals[0][1],
-           a11 = src->vals[1][1],
-           a12 = src->vals[2][1],
-           a20 = src->vals[0][2],
-           a21 = src->vals[1][2],
-           a22 = src->vals[2][2];
-
-    double b0 = a00*a11 - a01*a10,
-           b1 = a00*a12 - a02*a10,
-           b2 = a01*a12 - a02*a11,
-           b3 = a20,
-           b4 = a21,
-           b5 = a22;
-
-    double determinant = b0*b5
-                       - b1*b4
-                       + b2*b3;
-
-    if (determinant == 0) {
-        return false;
-    }
-
-    double invdet = 1.0 / determinant;
-    if (invdet > +FLT_MAX || invdet < -FLT_MAX || !isfinitef_((float)invdet)) {
-        return false;
-    }
-
-    b0 *= invdet;
-    b1 *= invdet;
-    b2 *= invdet;
-    b3 *= invdet;
-    b4 *= invdet;
-    b5 *= invdet;
-
-    dst->vals[0][0] = (float)( a11*b5 - a12*b4 );
-    dst->vals[1][0] = (float)( a02*b4 - a01*b5 );
-    dst->vals[2][0] = (float)(        +     b2 );
-    dst->vals[0][1] = (float)( a12*b3 - a10*b5 );
-    dst->vals[1][1] = (float)( a00*b5 - a02*b3 );
-    dst->vals[2][1] = (float)(        -     b1 );
-    dst->vals[0][2] = (float)( a10*b4 - a11*b3 );
-    dst->vals[1][2] = (float)( a01*b3 - a00*b4 );
-    dst->vals[2][2] = (float)(        +     b0 );
-
-    for (int r = 0; r < 3; ++r)
-    for (int c = 0; c < 3; ++c) {
-        if (!isfinitef_(dst->vals[r][c])) {
-            return false;
-        }
-    }
-    return true;
-}
-
-skcms_Matrix3x3 skcms_Matrix3x3_concat(const skcms_Matrix3x3* A, const skcms_Matrix3x3* B) {
-    skcms_Matrix3x3 m = { { { 0,0,0 },{ 0,0,0 },{ 0,0,0 } } };
-    for (int r = 0; r < 3; r++)
-        for (int c = 0; c < 3; c++) {
-            m.vals[r][c] = A->vals[r][0] * B->vals[0][c]
-                         + A->vals[r][1] * B->vals[1][c]
-                         + A->vals[r][2] * B->vals[2][c];
-        }
-    return m;
-}
-
-skcms_Vector3 skcms_MV_mul(const skcms_Matrix3x3* m, const skcms_Vector3* v) {
-    skcms_Vector3 dst = {{0,0,0}};
-    for (int row = 0; row < 3; ++row) {
-        dst.vals[row] = m->vals[row][0] * v->vals[0]
-                      + m->vals[row][1] * v->vals[1]
-                      + m->vals[row][2] * v->vals[2];
-    }
-    return dst;
-}
diff --git a/third_party/skcms/src/PortableMath.c b/third_party/skcms/src/PortableMath.c
deleted file mode 100644
index 52e8b7d1c8..0000000000
--- a/third_party/skcms/src/PortableMath.c
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "../skcms_internal.h"
-#include <limits.h>
-#include <string.h>
-
-#if defined(__clang__) || defined(__GNUC__)
-    #define small_memcpy __builtin_memcpy
-#else
-    #define small_memcpy memcpy
-#endif
-
-float log2f_(float x) {
-    // The first approximation of log2(x) is its exponent 'e', minus 127.
-    int32_t bits;
-    small_memcpy(&bits, &x, sizeof(bits));
-
-    float e = (float)bits * (1.0f / (1<<23));
-
-    // If we use the mantissa too we can refine the error signficantly.
-    int32_t m_bits = (bits & 0x007fffff) | 0x3f000000;
-    float m;
-    small_memcpy(&m, &m_bits, sizeof(m));
-
-    return (e - 124.225514990f
-              -   1.498030302f*m
-              -   1.725879990f/(0.3520887068f + m));
-}
-
-float exp2f_(float x) {
-    float fract = x - floorf_(x);
-
-    float fbits = (1.0f * (1<<23)) * (x + 121.274057500f
-                                        -   1.490129070f*fract
-                                        +  27.728023300f/(4.84252568f - fract));
-    if (fbits > INT_MAX) {
-        return INFINITY_;
-    } else if (fbits < INT_MIN) {
-        return -INFINITY_;
-    }
-    int32_t bits = (int32_t)fbits;
-    small_memcpy(&x, &bits, sizeof(x));
-    return x;
-}
-
-float powf_(float x, float y) {
-    return (x == 0) || (x == 1) ? x
-                                : exp2f_(log2f_(x) * y);
-}
diff --git a/third_party/skcms/src/TransferFunction.c b/third_party/skcms/src/TransferFunction.c
deleted file mode 100644
index 7bab9d9286..0000000000
--- a/third_party/skcms/src/TransferFunction.c
+++ /dev/null
@@ -1,432 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "../skcms_internal.h"
-#include <assert.h>
-#include <limits.h>
-#include <string.h>
-
-float skcms_TransferFunction_eval(const skcms_TransferFunction* tf, float x) {
-    float sign = x < 0 ? -1.0f : 1.0f;
-    x *= sign;
-
-    return sign * (x < tf->d ? tf->c * x + tf->f
-                             : powf_(tf->a * x + tf->b, tf->g) + tf->e);
-}
-
-bool skcms_TransferFunction_isValid(const skcms_TransferFunction* tf) {
-    // Reject obviously malformed inputs
-    if (!isfinitef_(tf->a + tf->b + tf->c + tf->d + tf->e + tf->f + tf->g)) {
-        return false;
-    }
-
-    // All of these parameters should be non-negative
-    if (tf->a < 0 || tf->c < 0 || tf->d < 0 || tf->g < 0) {
-        return false;
-    }
-
-    return true;
-}
-
-// TODO: Adjust logic here? This still assumes that purely linear inputs will have D > 1, which
-// we never generate. It also emits inverted linear using the same formulation. Standardize on
-// G == 1 here, too?
-bool skcms_TransferFunction_invert(const skcms_TransferFunction* src, skcms_TransferFunction* dst) {
-    // Original equation is:       y = (ax + b)^g + e   for x >= d
-    //                             y = cx + f           otherwise
-    //
-    // so 1st inverse is:          (y - e)^(1/g) = ax + b
-    //                             x = ((y - e)^(1/g) - b) / a
-    //
-    // which can be re-written as: x = (1/a)(y - e)^(1/g) - b/a
-    //                             x = ((1/a)^g)^(1/g) * (y - e)^(1/g) - b/a
-    //                             x = ([(1/a)^g]y + [-((1/a)^g)e]) ^ [1/g] + [-b/a]
-    //
-    // and 2nd inverse is:         x = (y - f) / c
-    // which can be re-written as: x = [1/c]y + [-f/c]
-    //
-    // and now both can be expressed in terms of the same parametric form as the
-    // original - parameters are enclosed in square brackets.
-    skcms_TransferFunction tf_inv = { 0, 0, 0, 0, 0, 0, 0 };
-
-    // This rejects obviously malformed inputs, as well as decreasing functions
-    if (!skcms_TransferFunction_isValid(src)) {
-        return false;
-    }
-
-    // There are additional constraints to be invertible
-    bool has_nonlinear = (src->d <= 1);
-    bool has_linear = (src->d > 0);
-
-    // Is the linear section not invertible?
-    if (has_linear && src->c == 0) {
-        return false;
-    }
-
-    // Is the nonlinear section not invertible?
-    if (has_nonlinear && (src->a == 0 || src->g == 0)) {
-        return false;
-    }
-
-    // If both segments are present, they need to line up
-    if (has_linear && has_nonlinear) {
-        float l_at_d = src->c * src->d + src->f;
-        float n_at_d = powf_(src->a * src->d + src->b, src->g) + src->e;
-        if (fabsf_(l_at_d - n_at_d) > (1 / 512.0f)) {
-            return false;
-        }
-    }
-
-    // Invert linear segment
-    if (has_linear) {
-        tf_inv.c = 1.0f / src->c;
-        tf_inv.f = -src->f / src->c;
-    }
-
-    // Invert nonlinear segment
-    if (has_nonlinear) {
-        tf_inv.g = 1.0f / src->g;
-        tf_inv.a = powf_(1.0f / src->a, src->g);
-        tf_inv.b = -tf_inv.a * src->e;
-        tf_inv.e = -src->b / src->a;
-    }
-
-    if (!has_linear) {
-        tf_inv.d = 0;
-    } else if (!has_nonlinear) {
-        // Any value larger than 1 works
-        tf_inv.d = 2.0f;
-    } else {
-        tf_inv.d = src->c * src->d + src->f;
-    }
-
-    *dst = tf_inv;
-    return true;
-}
-
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //
-
-// From here below we're approximating an skcms_Curve with an skcms_TransferFunction{g,a,b,c,d,e,f}:
-//
-//   tf(x) =  cx + f          x < d
-//   tf(x) = (ax + b)^g + e   x ≥ d
-//
-// When fitting, we add the additional constraint that both pieces meet at d:
-//
-//   cd + f = (ad + b)^g + e
-//
-// Solving for e and folding it through gives an alternate formulation of the non-linear piece:
-//
-//   tf(x) =                           cx + f   x < d
-//   tf(x) = (ax + b)^g - (ad + b)^g + cd + f   x ≥ d
-//
-// Our overall strategy is then:
-//    For a couple tolerances,
-//       - skcms_fit_linear(): fit c,d,f iteratively to as many points as our tolerance allows
-//       - invert c,d,f
-//       - fit_nonlinear():    fit g,a,b using Gauss-Newton given those inverted c,d,f
-//                             (and by constraint, inverted e) to the inverse of the table.
-//    Return the parameters with least maximum error.
-//
-// To run Gauss-Newton to find g,a,b, we'll also need the gradient of the residuals
-// of round-trip f_inv(x), the inverse of the non-linear piece of f(x).
-//
-//    let y = Table(x)
-//    r(x) = x - f_inv(y)
-//
-//    ∂r/∂g = ln(ay + b)*(ay + b)^g
-//          - ln(ad + b)*(ad + b)^g
-//    ∂r/∂a = yg(ay + b)^(g-1)
-//          - dg(ad + b)^(g-1)
-//    ∂r/∂b =  g(ay + b)^(g-1)
-//          -  g(ad + b)^(g-1)
-
-// Return the residual of roundtripping skcms_Curve(x) through f_inv(y) with parameters P,
-// and fill out the gradient of the residual into dfdP.
-static float rg_nonlinear(float x,
-                          const skcms_Curve* curve,
-                          const skcms_TransferFunction* tf,
-                          const float P[3],
-                          float dfdP[3]) {
-    const float y = skcms_eval_curve(curve, x);
-
-    const float g = P[0],  a = P[1],  b = P[2],
-                c = tf->c, d = tf->d, f = tf->f;
-
-    const float Y = fmaxf_(a*y + b, 0.0f),
-                D =        a*d + b;
-    assert (D >= 0);
-
-    // The gradient.
-    dfdP[0] = 0.69314718f*log2f_(Y)*powf_(Y, g)
-            - 0.69314718f*log2f_(D)*powf_(D, g);
-    dfdP[1] = y*g*powf_(Y, g-1)
-            - d*g*powf_(D, g-1);
-    dfdP[2] =   g*powf_(Y, g-1)
-            -   g*powf_(D, g-1);
-
-    // The residual.
-    const float f_inv = powf_(Y, g)
-                      - powf_(D, g)
-                      + c*d + f;
-    return x - f_inv;
-}
-
-int skcms_fit_linear(const skcms_Curve* curve, int N, float tol, float* c, float* d, float* f) {
-    assert(N > 1);
-    // We iteratively fit the first points to the TF's linear piece.
-    // We want the cx + f line to pass through the first and last points we fit exactly.
-    //
-    // As we walk along the points we find the minimum and maximum slope of the line before the
-    // error would exceed our tolerance.  We stop when the range [slope_min, slope_max] becomes
-    // emtpy, when we definitely can't add any more points.
-    //
-    // Some points' error intervals may intersect the running interval but not lie fully
-    // within it.  So we keep track of the last point we saw that is a valid end point candidate,
-    // and once the search is done, back up to build the line through *that* point.
-    const float dx = 1.0f / (N - 1);
-
-    int lin_points = 1;
-    *f = skcms_eval_curve(curve, 0);
-
-    float slope_min = -INFINITY_;
-    float slope_max = +INFINITY_;
-    for (int i = 1; i < N; ++i) {
-        float x = i * dx;
-        float y = skcms_eval_curve(curve, x);
-
-        float slope_max_i = (y + tol - *f) / x,
-              slope_min_i = (y - tol - *f) / x;
-        if (slope_max_i < slope_min || slope_max < slope_min_i) {
-            // Slope intervals would no longer overlap.
-            break;
-        }
-        slope_max = fminf_(slope_max, slope_max_i);
-        slope_min = fmaxf_(slope_min, slope_min_i);
-
-        float cur_slope = (y - *f) / x;
-        if (slope_min <= cur_slope && cur_slope <= slope_max) {
-            lin_points = i + 1;
-            *c = cur_slope;
-        }
-    }
-
-    // Set D to the last point that met our tolerance.
-    *d = (lin_points - 1) * dx;
-    return lin_points;
-}
-
-static bool gauss_newton_step(const skcms_Curve* curve,
-                              const skcms_TransferFunction* tf,
-                              float P[3],
-                              float x0, float dx, int N) {
-    // We'll sample x from the range [x0,x1] (both inclusive) N times with even spacing.
-    //
-    // We want to do P' = P + (Jf^T Jf)^-1 Jf^T r(P),
-    //   where r(P) is the residual vector
-    //   and Jf is the Jacobian matrix of f(), ∂r/∂P.
-    //
-    // Let's review the shape of each of these expressions:
-    //   r(P)   is [N x 1], a column vector with one entry per value of x tested
-    //   Jf     is [N x 3], a matrix with an entry for each (x,P) pair
-    //   Jf^T   is [3 x N], the transpose of Jf
-    //
-    //   Jf^T Jf   is [3 x N] * [N x 3] == [3 x 3], a 3x3 matrix,
-    //                                              and so is its inverse (Jf^T Jf)^-1
-    //   Jf^T r(P) is [3 x N] * [N x 1] == [3 x 1], a column vector with the same shape as P
-    //
-    // Our implementation strategy to get to the final ∆P is
-    //   1) evaluate Jf^T Jf,   call that lhs
-    //   2) evaluate Jf^T r(P), call that rhs
-    //   3) invert lhs
-    //   4) multiply inverse lhs by rhs
-    //
-    // This is a friendly implementation strategy because we don't have to have any
-    // buffers that scale with N, and equally nice don't have to perform any matrix
-    // operations that are variable size.
-    //
-    // Other implementation strategies could trade this off, e.g. evaluating the
-    // pseudoinverse of Jf ( (Jf^T Jf)^-1 Jf^T ) directly, then multiplying that by
-    // the residuals.  That would probably require implementing singular value
-    // decomposition, and would create a [3 x N] matrix to be multiplied by the
-    // [N x 1] residual vector, but on the upside I think that'd eliminate the
-    // possibility of this gauss_newton_step() function ever failing.
-
-    // 0) start off with lhs and rhs safely zeroed.
-    skcms_Matrix3x3 lhs = {{ {0,0,0}, {0,0,0}, {0,0,0} }};
-    skcms_Vector3   rhs = {  {0,0,0} };
-
-    // 1,2) evaluate lhs and evaluate rhs
-    //   We want to evaluate Jf only once, but both lhs and rhs involve Jf^T,
-    //   so we'll have to update lhs and rhs at the same time.
-    for (int i = 0; i < N; i++) {
-        float x = x0 + i*dx;
-
-        float dfdP[3] = {0,0,0};
-        float resid = rg_nonlinear(x,curve,tf,P, dfdP);
-
-        for (int r = 0; r < 3; r++) {
-            for (int c = 0; c < 3; c++) {
-                lhs.vals[r][c] += dfdP[r] * dfdP[c];
-            }
-            rhs.vals[r] += dfdP[r] * resid;
-        }
-    }
-
-    // If any of the 3 P parameters are unused, this matrix will be singular.
-    // Detect those cases and fix them up to indentity instead, so we can invert.
-    for (int k = 0; k < 3; k++) {
-        if (lhs.vals[0][k]==0 && lhs.vals[1][k]==0 && lhs.vals[2][k]==0 &&
-            lhs.vals[k][0]==0 && lhs.vals[k][1]==0 && lhs.vals[k][2]==0) {
-            lhs.vals[k][k] = 1;
-        }
-    }
-
-    // 3) invert lhs
-    skcms_Matrix3x3 lhs_inv;
-    if (!skcms_Matrix3x3_invert(&lhs, &lhs_inv)) {
-        return false;
-    }
-
-    // 4) multiply inverse lhs by rhs
-    skcms_Vector3 dP = skcms_MV_mul(&lhs_inv, &rhs);
-    P[0] += dP.vals[0];
-    P[1] += dP.vals[1];
-    P[2] += dP.vals[2];
-    return isfinitef_(P[0]) && isfinitef_(P[1]) && isfinitef_(P[2]);
-}
-
-
-// Fit the points in [L,N) to the non-linear piece of tf, or return false if we can't.
-static bool fit_nonlinear(const skcms_Curve* curve, int L, int N, skcms_TransferFunction* tf) {
-    float P[3] = { tf->g, tf->a, tf->b };
-
-    // No matter where we start, dx should always represent N even steps from 0 to 1.
-    const float dx = 1.0f / (N-1);
-
-    for (int j = 0; j < 3/*TODO: tune*/; j++) {
-        // These extra constraints a >= 0 and ad+b >= 0 are not modeled in the optimization.
-        // We don't really know how to fix up a if it goes negative.
-        if (P[1] < 0) {
-            return false;
-        }
-        // If ad+b goes negative, we feel just barely not uneasy enough to tweak b so ad+b is zero.
-        if (P[1] * tf->d + P[2] < 0) {
-            P[2] = -P[1] * tf->d;
-        }
-        assert (P[1] >= 0 &&
-                P[1] * tf->d + P[2] >= 0);
-
-        if (!gauss_newton_step(curve, tf,
-                               P,
-                               L*dx, dx, N-L)) {
-            return false;
-        }
-    }
-
-    // We need to apply our fixups one last time
-    if (P[1] < 0) {
-        return false;
-    }
-    if (P[1] * tf->d + P[2] < 0) {
-        P[2] = -P[1] * tf->d;
-    }
-
-    tf->g = P[0];
-    tf->a = P[1];
-    tf->b = P[2];
-    tf->e =   tf->c*tf->d + tf->f
-      - powf_(tf->a*tf->d + tf->b, tf->g);
-    return true;
-}
-
-bool skcms_ApproximateCurve(const skcms_Curve* curve,
-                            skcms_TransferFunction* approx,
-                            float* max_error) {
-    if (!curve || !approx || !max_error) {
-        return false;
-    }
-
-    if (curve->table_entries == 0) {
-        // No point approximating an skcms_TransferFunction with an skcms_TransferFunction!
-        return false;
-    }
-
-    if (curve->table_entries == 1 || curve->table_entries > (uint32_t)INT_MAX) {
-        // We need at least two points, and must put some reasonable cap on the maximum number.
-        return false;
-    }
-
-    int N = (int)curve->table_entries;
-    const float dx = 1.0f / (N - 1);
-
-    *max_error = INFINITY_;
-    const float kTolerances[] = { 1.5f / 65535.0f, 1.0f / 512.0f };
-    for (int t = 0; t < ARRAY_COUNT(kTolerances); t++) {
-        skcms_TransferFunction tf,
-                               tf_inv;
-        int L = skcms_fit_linear(curve, N, kTolerances[t], &tf.c, &tf.d, &tf.f);
-
-        if (L == N) {
-            // If the entire data set was linear, move the coefficients to the nonlinear portion
-            // with G == 1.  This lets use a canonical representation with d == 0.
-            tf.g = 1;
-            tf.a = tf.c;
-            tf.b = tf.f;
-            tf.c = tf.d = tf.e = tf.f = 0;
-        } else if (L == N - 1) {
-            // Degenerate case with only two points in the nonlinear segment. Solve directly.
-            tf.g = 1;
-            tf.a = (skcms_eval_curve(curve, (N-1)*dx) -
-                    skcms_eval_curve(curve, (N-2)*dx))
-                 / dx;
-            tf.b = skcms_eval_curve(curve, (N-2)*dx)
-                 - tf.a * (N-2)*dx;
-            tf.e = 0;
-        } else {
-            // Start by guessing a gamma-only curve through the midpoint.
-            int mid = (L + N) / 2;
-            float mid_x = mid / (N - 1.0f);
-            float mid_y = skcms_eval_curve(curve, mid_x);
-            tf.g = log2f_(mid_y) / log2f_(mid_x);;
-            tf.a = 1;
-            tf.b = 0;
-            tf.e =    tf.c*tf.d + tf.f
-              - powf_(tf.a*tf.d + tf.b, tf.g);
-
-
-            if (!skcms_TransferFunction_invert(&tf, &tf_inv) ||
-                !fit_nonlinear(curve, L,N, &tf_inv)) {
-                continue;
-            }
-
-            // We fit tf_inv, so calculate tf to keep in sync.
-            if (!skcms_TransferFunction_invert(&tf_inv, &tf)) {
-                continue;
-            }
-        }
-
-        // We find our error by roundtripping the table through tf_inv.
-        //
-        // (The most likely use case for this approximation is to be inverted and
-        // used as the transfer function for a destination color space.)
-        //
-        // We've kept tf and tf_inv in sync above, but we can't guarantee that tf is
-        // invertible, so re-verify that here (and use the new inverse for testing).
-        if (!skcms_TransferFunction_invert(&tf, &tf_inv)) {
-            continue;
-        }
-
-        float err = skcms_MaxRoundtripError(curve, &tf_inv);
-        if (*max_error > err) {
-            *max_error = err;
-            *approx    = tf;
-        }
-    }
-    return isfinitef_(*max_error);
-}
diff --git a/third_party/skcms/src/Transform.c b/third_party/skcms/src/Transform.c
deleted file mode 100644
index 2f4216ba8b..0000000000
--- a/third_party/skcms/src/Transform.c
+++ /dev/null
@@ -1,694 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "../skcms_internal.h"
-#include <assert.h>
-#include <limits.h>
-#include <stdint.h>
-#include <string.h>
-
-// Without this wasm would try to use the N=4 128-bit vector code path,
-// which while ideal, causes tons of compiler problems.  This would be
-// a good thing to revisit as emcc matures (currently 1.38.5).
-#if 1 && defined(__EMSCRIPTEN_major__)
-    #if !defined(SKCMS_PORTABLE)
-        #define  SKCMS_PORTABLE
-    #endif
-#endif
-
-extern bool g_skcms_dump_profile;
-bool g_skcms_dump_profile = false;
-
-#if !defined(NDEBUG) && defined(__clang__)
-    // Basic profiling tools to time each Op.  Not at all thread safe.
-
-    #include <stdio.h>
-    #include <stdlib.h>
-
-    #if defined(__arm__) || defined(__aarch64__)
-        #include <time.h>
-        static const char* now_units = "ticks";
-        static uint64_t now() { return (uint64_t)clock(); }
-    #else
-        static const char* now_units = "cycles";
-        static uint64_t now() { return __builtin_readcyclecounter(); }
-    #endif
-
-    #define M(op) +1
-    static uint64_t counts[FOREACH_Op(M)];
-    #undef M
-
-    static void profile_dump_stats() {
-    #define M(op) #op,
-        static const char* names[] = { FOREACH_Op(M) };
-    #undef M
-        for (int i = 0; i < ARRAY_COUNT(counts); i++) {
-            if (counts[i]) {
-                fprintf(stderr, "%16s: %12llu %s\n",
-                        names[i], (unsigned long long)counts[i], now_units);
-            }
-        }
-    }
-
-    static inline Op profile_next_op(Op op) {
-        if (__builtin_expect(g_skcms_dump_profile, false)) {
-            static uint64_t start    = 0;
-            static uint64_t* current = NULL;
-
-            if (!current) {
-                atexit(profile_dump_stats);
-            } else {
-                *current += now() - start;
-            }
-
-            current = &counts[op];
-            start   = now();
-        }
-        return op;
-    }
-#else
-    static inline Op profile_next_op(Op op) {
-        (void)g_skcms_dump_profile;
-        return op;
-    }
-#endif
-
-#if defined(__clang__)
-    typedef float    __attribute__((ext_vector_type(4)))   Fx4;
-    typedef int32_t  __attribute__((ext_vector_type(4))) I32x4;
-    typedef uint64_t __attribute__((ext_vector_type(4))) U64x4;
-    typedef uint32_t __attribute__((ext_vector_type(4))) U32x4;
-    typedef uint16_t __attribute__((ext_vector_type(4))) U16x4;
-    typedef uint8_t  __attribute__((ext_vector_type(4)))  U8x4;
-
-    typedef float    __attribute__((ext_vector_type(8)))   Fx8;
-    typedef int32_t  __attribute__((ext_vector_type(8))) I32x8;
-    typedef uint64_t __attribute__((ext_vector_type(8))) U64x8;
-    typedef uint32_t __attribute__((ext_vector_type(8))) U32x8;
-    typedef uint16_t __attribute__((ext_vector_type(8))) U16x8;
-    typedef uint8_t  __attribute__((ext_vector_type(8)))  U8x8;
-
-    typedef float    __attribute__((ext_vector_type(16)))   Fx16;
-    typedef int32_t  __attribute__((ext_vector_type(16))) I32x16;
-    typedef uint64_t __attribute__((ext_vector_type(16))) U64x16;
-    typedef uint32_t __attribute__((ext_vector_type(16))) U32x16;
-    typedef uint16_t __attribute__((ext_vector_type(16))) U16x16;
-    typedef uint8_t  __attribute__((ext_vector_type(16)))  U8x16;
-#elif defined(__GNUC__)
-    typedef float    __attribute__((vector_size(16)))   Fx4;
-    typedef int32_t  __attribute__((vector_size(16))) I32x4;
-    typedef uint64_t __attribute__((vector_size(32))) U64x4;
-    typedef uint32_t __attribute__((vector_size(16))) U32x4;
-    typedef uint16_t __attribute__((vector_size( 8))) U16x4;
-    typedef uint8_t  __attribute__((vector_size( 4)))  U8x4;
-
-    typedef float    __attribute__((vector_size(32)))   Fx8;
-    typedef int32_t  __attribute__((vector_size(32))) I32x8;
-    typedef uint64_t __attribute__((vector_size(64))) U64x8;
-    typedef uint32_t __attribute__((vector_size(32))) U32x8;
-    typedef uint16_t __attribute__((vector_size(16))) U16x8;
-    typedef uint8_t  __attribute__((vector_size( 8)))  U8x8;
-
-    typedef float    __attribute__((vector_size( 64)))   Fx16;
-    typedef int32_t  __attribute__((vector_size( 64))) I32x16;
-    typedef uint64_t __attribute__((vector_size(128))) U64x16;
-    typedef uint32_t __attribute__((vector_size( 64))) U32x16;
-    typedef uint16_t __attribute__((vector_size( 32))) U16x16;
-    typedef uint8_t  __attribute__((vector_size( 16)))  U8x16;
-#endif
-
-// First, instantiate our default exec_ops() implementation using the default compiliation target.
-
-#if defined(SKCMS_PORTABLE) || !(defined(__clang__) || defined(__GNUC__))
-    #define N 1
-
-    #define F   float
-    #define U64 uint64_t
-    #define U32 uint32_t
-    #define I32 int32_t
-    #define U16 uint16_t
-    #define U8  uint8_t
-
-    #define F0 0.0f
-    #define F1 1.0f
-
-#elif defined(__AVX512F__)
-    #define N 16
-
-    #define F     Fx16
-    #define U64 U64x16
-    #define U32 U32x16
-    #define I32 I32x16
-    #define U16 U16x16
-    #define U8   U8x16
-
-    #define F0 (F){0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0}
-    #define F1 (F){1,1,1,1, 1,1,1,1, 1,1,1,1, 1,1,1,1}
-#elif defined(__AVX__)
-    #define N 8
-
-    #define F     Fx8
-    #define U64 U64x8
-    #define U32 U32x8
-    #define I32 I32x8
-    #define U16 U16x8
-    #define U8   U8x8
-
-    #define F0 (F){0,0,0,0, 0,0,0,0}
-    #define F1 (F){1,1,1,1, 1,1,1,1}
-#else
-    #define N 4
-
-    #define F     Fx4
-    #define U64 U64x4
-    #define U32 U32x4
-    #define I32 I32x4
-    #define U16 U16x4
-    #define U8   U8x4
-
-    #define F0 (F){0,0,0,0}
-    #define F1 (F){1,1,1,1}
-#endif
-
-#define NS(id) id
-#define ATTR
-    #include "Transform_inl.h"
-#undef N
-#undef F
-#undef U64
-#undef U32
-#undef I32
-#undef U16
-#undef U8
-#undef F0
-#undef F1
-#undef NS
-#undef ATTR
-
-// Now, instantiate any other versions of run_program() we may want for runtime detection.
-#if !defined(SKCMS_PORTABLE) && (defined(__clang__) || defined(__GNUC__)) \
-        && defined(__x86_64__) && !defined(__AVX2__)
-    #define N 8
-    #define F     Fx8
-    #define U64 U64x8
-    #define U32 U32x8
-    #define I32 I32x8
-    #define U16 U16x8
-    #define U8   U8x8
-    #define F0 (F){0,0,0,0, 0,0,0,0}
-    #define F1 (F){1,1,1,1, 1,1,1,1}
-
-    #define NS(id) id ## _hsw
-    #define ATTR __attribute__((target("avx2,f16c")))
-
-    // We check these guards to see if we have support for these features.
-    // They're likely _not_ defined here in our baseline build config.
-    #ifndef __AVX__
-        #define __AVX__ 1
-        #define UNDEF_AVX
-    #endif
-    #ifndef __F16C__
-        #define __F16C__ 1
-        #define UNDEF_F16C
-    #endif
-    #ifndef __AVX2__
-        #define __AVX2__ 1
-        #define UNDEF_AVX2
-    #endif
-
-    #include "Transform_inl.h"
-
-    #undef N
-    #undef F
-    #undef U64
-    #undef U32
-    #undef I32
-    #undef U16
-    #undef U8
-    #undef F0
-    #undef F1
-    #undef NS
-    #undef ATTR
-
-    #ifdef UNDEF_AVX
-        #undef __AVX__
-        #undef UNDEF_AVX
-    #endif
-    #ifdef UNDEF_F16C
-        #undef __F16C__
-        #undef UNDEF_F16C
-    #endif
-    #ifdef UNDEF_AVX2
-        #undef __AVX2__
-        #undef UNDEF_AVX2
-    #endif
-
-    #define TEST_FOR_HSW
-
-    static bool hsw_ok_ = false;
-    static void check_hsw_ok() {
-        // See http://www.sandpile.org/x86/cpuid.htm
-
-        // First, a basic cpuid(1).
-        uint32_t eax, ebx, ecx, edx;
-        __asm__ __volatile__("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
-                                     : "0"(1), "2"(0));
-
-        // Sanity check for prerequisites.
-        if ((edx & (1<<25)) != (1<<25)) { return; }   // SSE
-        if ((edx & (1<<26)) != (1<<26)) { return; }   // SSE2
-        if ((ecx & (1<< 0)) != (1<< 0)) { return; }   // SSE3
-        if ((ecx & (1<< 9)) != (1<< 9)) { return; }   // SSSE3
-        if ((ecx & (1<<19)) != (1<<19)) { return; }   // SSE4.1
-        if ((ecx & (1<<20)) != (1<<20)) { return; }   // SSE4.2
-
-        if ((ecx & (3<<26)) != (3<<26)) { return; }   // XSAVE + OSXSAVE
-
-        {
-            uint32_t eax_xgetbv, edx_xgetbv;
-            __asm__ __volatile__("xgetbv" : "=a"(eax_xgetbv), "=d"(edx_xgetbv) : "c"(0));
-            if ((eax_xgetbv & (3<<1)) != (3<<1)) { return; }  // XMM+YMM state saved?
-        }
-
-        if ((ecx & (1<<28)) != (1<<28)) { return; }   // AVX
-        if ((ecx & (1<<29)) != (1<<29)) { return; }   // F16C
-        if ((ecx & (1<<12)) != (1<<12)) { return; }   // FMA  (TODO: not currently used)
-
-        // Call cpuid(7) to check for our final AVX2 feature bit!
-        __asm__ __volatile__("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
-                                     : "0"(7), "2"(0));
-        if ((ebx & (1<< 5)) != (1<< 5)) { return; }   // AVX2
-
-        hsw_ok_ = true;
-    }
-
-    #if defined(_MSC_VER)
-        #include <Windows.h>
-        INIT_ONCE check_hsw_ok_once = INIT_ONCE_STATIC_INIT;
-
-        static BOOL check_hsw_ok_InitOnce_wrapper(INIT_ONCE* once, void* param, void** ctx) {
-            (void)once;
-            (void)param;
-            (void)ctx;
-            check_hsw_ok();
-            return TRUE;
-        }
-
-        static bool hsw_ok() {
-            InitOnceExecuteOnce(&check_hsw_ok_once, check_hsw_ok_InitOnce_wrapper, NULL, NULL);
-            return hsw_ok_;
-        }
-    #else
-        #include <pthread.h>
-        static pthread_once_t check_hsw_ok_once = PTHREAD_ONCE_INIT;
-
-        static bool hsw_ok() {
-            pthread_once(&check_hsw_ok_once, check_hsw_ok);
-            return hsw_ok_;
-        }
-    #endif
-
-#endif
-
-static bool is_identity_tf(const skcms_TransferFunction* tf) {
-    return tf->g == 1 && tf->a == 1
-        && tf->b == 0 && tf->c == 0 && tf->d == 0 && tf->e == 0 && tf->f == 0;
-}
-
-typedef struct {
-    Op          op;
-    const void* arg;
-} OpAndArg;
-
-static OpAndArg select_curve_op(const skcms_Curve* curve, int channel) {
-    static const struct { Op parametric, table_8, table_16; } ops[] = {
-        { Op_tf_r, Op_table_8_r, Op_table_16_r },
-        { Op_tf_g, Op_table_8_g, Op_table_16_g },
-        { Op_tf_b, Op_table_8_b, Op_table_16_b },
-        { Op_tf_a, Op_table_8_a, Op_table_16_a },
-    };
-
-    if (curve->table_entries == 0) {
-        return is_identity_tf(&curve->parametric)
-            ? (OpAndArg){ Op_noop, NULL }
-            : (OpAndArg){ ops[channel].parametric, &curve->parametric };
-    } else if (curve->table_8) {
-        return (OpAndArg){ ops[channel].table_8,  curve };
-    } else if (curve->table_16) {
-        return (OpAndArg){ ops[channel].table_16, curve };
-    }
-
-    assert(false);
-    return (OpAndArg){Op_noop,NULL};
-}
-
-static size_t bytes_per_pixel(skcms_PixelFormat fmt) {
-    switch (fmt >> 1) {   // ignore rgb/bgr
-        case skcms_PixelFormat_A_8           >> 1: return  1;
-        case skcms_PixelFormat_G_8           >> 1: return  1;
-        case skcms_PixelFormat_ABGR_4444     >> 1: return  2;
-        case skcms_PixelFormat_RGB_565       >> 1: return  2;
-        case skcms_PixelFormat_RGB_888       >> 1: return  3;
-        case skcms_PixelFormat_RGBA_8888     >> 1: return  4;
-        case skcms_PixelFormat_RGBA_1010102  >> 1: return  4;
-        case skcms_PixelFormat_RGB_161616    >> 1: return  6;
-        case skcms_PixelFormat_RGBA_16161616 >> 1: return  8;
-        case skcms_PixelFormat_RGB_hhh       >> 1: return  6;
-        case skcms_PixelFormat_RGBA_hhhh     >> 1: return  8;
-        case skcms_PixelFormat_RGB_fff       >> 1: return 12;
-        case skcms_PixelFormat_RGBA_ffff     >> 1: return 16;
-    }
-    assert(false);
-    return 0;
-}
-
-static bool prep_for_destination(const skcms_ICCProfile* profile,
-                                 skcms_Matrix3x3* fromXYZD50,
-                                 skcms_TransferFunction* invR,
-                                 skcms_TransferFunction* invG,
-                                 skcms_TransferFunction* invB) {
-    // We only support destinations with parametric transfer functions
-    // and with gamuts that can be transformed from XYZD50.
-    return profile->has_trc
-        && profile->has_toXYZD50
-        && profile->trc[0].table_entries == 0
-        && profile->trc[1].table_entries == 0
-        && profile->trc[2].table_entries == 0
-        && skcms_TransferFunction_invert(&profile->trc[0].parametric, invR)
-        && skcms_TransferFunction_invert(&profile->trc[1].parametric, invG)
-        && skcms_TransferFunction_invert(&profile->trc[2].parametric, invB)
-        && skcms_Matrix3x3_invert(&profile->toXYZD50, fromXYZD50);
-}
-
-bool skcms_Transform(const void*             src,
-                     skcms_PixelFormat       srcFmt,
-                     skcms_AlphaFormat       srcAlpha,
-                     const skcms_ICCProfile* srcProfile,
-                     void*                   dst,
-                     skcms_PixelFormat       dstFmt,
-                     skcms_AlphaFormat       dstAlpha,
-                     const skcms_ICCProfile* dstProfile,
-                     size_t                  nz) {
-    const size_t dst_bpp = bytes_per_pixel(dstFmt),
-                 src_bpp = bytes_per_pixel(srcFmt);
-    // Let's just refuse if the request is absurdly big.
-    if (nz * dst_bpp > INT_MAX || nz * src_bpp > INT_MAX) {
-        return false;
-    }
-    int n = (int)nz;
-
-    // Null profiles default to sRGB. Passing null for both is handy when doing format conversion.
-    if (!srcProfile) {
-        srcProfile = skcms_sRGB_profile();
-    }
-    if (!dstProfile) {
-        dstProfile = skcms_sRGB_profile();
-    }
-
-    // We can't transform in place unless the PixelFormats are the same size.
-    if (dst == src && (dstFmt >> 1) != (srcFmt >> 1)) {
-        return false;
-    }
-    // TODO: this check lazilly disallows U16 <-> F16, but that would actually be fine.
-    // TODO: more careful alias rejection (like, dst == src + 1)?
-
-    Op          program  [32];
-    const void* arguments[32];
-
-    Op*          ops  = program;
-    const void** args = arguments;
-
-    skcms_TransferFunction inv_dst_tf_r, inv_dst_tf_g, inv_dst_tf_b;
-    skcms_Matrix3x3        from_xyz;
-
-    switch (srcFmt >> 1) {
-        default: return false;
-        case skcms_PixelFormat_A_8           >> 1: *ops++ = Op_load_a8;       break;
-        case skcms_PixelFormat_G_8           >> 1: *ops++ = Op_load_g8;       break;
-        case skcms_PixelFormat_ABGR_4444     >> 1: *ops++ = Op_load_4444;     break;
-        case skcms_PixelFormat_RGB_565       >> 1: *ops++ = Op_load_565;      break;
-        case skcms_PixelFormat_RGB_888       >> 1: *ops++ = Op_load_888;      break;
-        case skcms_PixelFormat_RGBA_8888     >> 1: *ops++ = Op_load_8888;     break;
-        case skcms_PixelFormat_RGBA_1010102  >> 1: *ops++ = Op_load_1010102;  break;
-        case skcms_PixelFormat_RGB_161616    >> 1: *ops++ = Op_load_161616;   break;
-        case skcms_PixelFormat_RGBA_16161616 >> 1: *ops++ = Op_load_16161616; break;
-        case skcms_PixelFormat_RGB_hhh       >> 1: *ops++ = Op_load_hhh;      break;
-        case skcms_PixelFormat_RGBA_hhhh     >> 1: *ops++ = Op_load_hhhh;     break;
-        case skcms_PixelFormat_RGB_fff       >> 1: *ops++ = Op_load_fff;      break;
-        case skcms_PixelFormat_RGBA_ffff     >> 1: *ops++ = Op_load_ffff;     break;
-    }
-    if (srcFmt & 1) {
-        *ops++ = Op_swap_rb;
-    }
-    skcms_ICCProfile gray_dst_profile;
-    if ((dstFmt >> 1) == (skcms_PixelFormat_G_8 >> 1)) {
-        // When transforming to gray, stop at XYZ (by setting toXYZ to identity), then transform
-        // luminance (Y) by the destination transfer function.
-        gray_dst_profile = *dstProfile;
-        skcms_SetXYZD50(&gray_dst_profile, &skcms_XYZD50_profile()->toXYZD50);
-        dstProfile = &gray_dst_profile;
-    }
-
-    if (srcProfile->data_color_space == skcms_Signature_CMYK) {
-        // Photoshop creates CMYK images as inverse CMYK.
-        // These happen to be the only ones we've _ever_ seen.
-        *ops++ = Op_invert;
-        // With CMYK, ignore the alpha type, to avoid changing K or conflating CMY with K.
-        srcAlpha = skcms_AlphaFormat_Unpremul;
-    }
-
-    if (srcAlpha == skcms_AlphaFormat_Opaque) {
-        *ops++ = Op_force_opaque;
-    } else if (srcAlpha == skcms_AlphaFormat_PremulAsEncoded) {
-        *ops++ = Op_unpremul;
-    }
-
-    // TODO: We can skip this work if both srcAlpha and dstAlpha are PremulLinear, and the profiles
-    // are the same. Also, if dstAlpha is PremulLinear, and SrcAlpha is Opaque.
-    if (dstProfile != srcProfile ||
-        srcAlpha == skcms_AlphaFormat_PremulLinear ||
-        dstAlpha == skcms_AlphaFormat_PremulLinear) {
-
-        if (!prep_for_destination(dstProfile,
-                                  &from_xyz, &inv_dst_tf_r, &inv_dst_tf_b, &inv_dst_tf_g)) {
-            return false;
-        }
-
-        if (srcProfile->has_A2B) {
-            if (srcProfile->A2B.input_channels) {
-                for (int i = 0; i < (int)srcProfile->A2B.input_channels; i++) {
-                    OpAndArg oa = select_curve_op(&srcProfile->A2B.input_curves[i], i);
-                    if (oa.op != Op_noop) {
-                        *ops++  = oa.op;
-                        *args++ = oa.arg;
-                    }
-                }
-                switch (srcProfile->A2B.input_channels) {
-                    case 3: *ops++ = srcProfile->A2B.grid_8 ? Op_clut_3D_8 : Op_clut_3D_16; break;
-                    case 4: *ops++ = srcProfile->A2B.grid_8 ? Op_clut_4D_8 : Op_clut_4D_16; break;
-                    default: return false;
-                }
-                *args++ = &srcProfile->A2B;
-            }
-
-            if (srcProfile->A2B.matrix_channels == 3) {
-                for (int i = 0; i < 3; i++) {
-                    OpAndArg oa = select_curve_op(&srcProfile->A2B.matrix_curves[i], i);
-                    if (oa.op != Op_noop) {
-                        *ops++  = oa.op;
-                        *args++ = oa.arg;
-                    }
-                }
-
-                static const skcms_Matrix3x4 I = {{
-                    {1,0,0,0},
-                    {0,1,0,0},
-                    {0,0,1,0},
-                }};
-                if (0 != memcmp(&I, &srcProfile->A2B.matrix, sizeof(I))) {
-                    *ops++  = Op_matrix_3x4;
-                    *args++ = &srcProfile->A2B.matrix;
-                }
-            }
-
-            if (srcProfile->A2B.output_channels == 3) {
-                for (int i = 0; i < 3; i++) {
-                    OpAndArg oa = select_curve_op(&srcProfile->A2B.output_curves[i], i);
-                    if (oa.op != Op_noop) {
-                        *ops++  = oa.op;
-                        *args++ = oa.arg;
-                    }
-                }
-            }
-
-            if (srcProfile->pcs == skcms_Signature_Lab) {
-                *ops++ = Op_lab_to_xyz;
-            }
-
-        } else if (srcProfile->has_trc && srcProfile->has_toXYZD50) {
-            for (int i = 0; i < 3; i++) {
-                OpAndArg oa = select_curve_op(&srcProfile->trc[i], i);
-                if (oa.op != Op_noop) {
-                    *ops++  = oa.op;
-                    *args++ = oa.arg;
-                }
-            }
-        } else {
-            return false;
-        }
-
-        // At this point our source colors are linear, either RGB (XYZ-type profiles)
-        // or XYZ (A2B-type profiles). Unpremul is a linear operation (multiply by a
-        // constant 1/a), so either way we can do it now if needed.
-        if (srcAlpha == skcms_AlphaFormat_PremulLinear) {
-            *ops++ = Op_unpremul;
-        }
-
-        // A2B sources should already be in XYZD50 at this point.
-        // Others still need to be transformed using their toXYZD50 matrix.
-        // N.B. There are profiles that contain both A2B tags and toXYZD50 matrices.
-        // If we use the A2B tags, we need to ignore the XYZD50 matrix entirely.
-        assert (srcProfile->has_A2B || srcProfile->has_toXYZD50);
-        static const skcms_Matrix3x3 I = {{
-            { 1.0f, 0.0f, 0.0f },
-            { 0.0f, 1.0f, 0.0f },
-            { 0.0f, 0.0f, 1.0f },
-        }};
-        const skcms_Matrix3x3* to_xyz = srcProfile->has_A2B ? &I : &srcProfile->toXYZD50;
-
-        // There's a chance the source and destination gamuts are identical,
-        // in which case we can skip the gamut transform.
-        if (0 != memcmp(&dstProfile->toXYZD50, to_xyz, sizeof(skcms_Matrix3x3))) {
-            // Concat the entire gamut transform into from_xyz,
-            // now slightly misnamed but it's a handy spot to stash the result.
-            from_xyz = skcms_Matrix3x3_concat(&from_xyz, to_xyz);
-            *ops++  = Op_matrix_3x3;
-            *args++ = &from_xyz;
-        }
-
-        if (dstAlpha == skcms_AlphaFormat_PremulLinear) {
-            *ops++ = Op_premul;
-        }
-
-        // Encode back to dst RGB using its parametric transfer functions.
-        if (!is_identity_tf(&inv_dst_tf_r)) { *ops++ = Op_tf_r; *args++ = &inv_dst_tf_r; }
-        if (!is_identity_tf(&inv_dst_tf_g)) { *ops++ = Op_tf_g; *args++ = &inv_dst_tf_g; }
-        if (!is_identity_tf(&inv_dst_tf_b)) { *ops++ = Op_tf_b; *args++ = &inv_dst_tf_b; }
-    }
-
-    if (dstAlpha == skcms_AlphaFormat_Opaque) {
-        *ops++ = Op_force_opaque;
-    } else if (dstAlpha == skcms_AlphaFormat_PremulAsEncoded) {
-        *ops++ = Op_premul;
-    }
-    if (dstFmt & 1) {
-        *ops++ = Op_swap_rb;
-    }
-    if (dstFmt < skcms_PixelFormat_RGB_hhh) {
-        *ops++ = Op_clamp;
-    }
-    switch (dstFmt >> 1) {
-        default: return false;
-        case skcms_PixelFormat_A_8           >> 1: *ops++ = Op_store_a8;       break;
-        case skcms_PixelFormat_G_8           >> 1: *ops++ = Op_store_g8;       break;
-        case skcms_PixelFormat_ABGR_4444     >> 1: *ops++ = Op_store_4444;     break;
-        case skcms_PixelFormat_RGB_565       >> 1: *ops++ = Op_store_565;      break;
-        case skcms_PixelFormat_RGB_888       >> 1: *ops++ = Op_store_888;      break;
-        case skcms_PixelFormat_RGBA_8888     >> 1: *ops++ = Op_store_8888;     break;
-        case skcms_PixelFormat_RGBA_1010102  >> 1: *ops++ = Op_store_1010102;  break;
-        case skcms_PixelFormat_RGB_161616    >> 1: *ops++ = Op_store_161616;   break;
-        case skcms_PixelFormat_RGBA_16161616 >> 1: *ops++ = Op_store_16161616; break;
-        case skcms_PixelFormat_RGB_hhh       >> 1: *ops++ = Op_store_hhh;      break;
-        case skcms_PixelFormat_RGBA_hhhh     >> 1: *ops++ = Op_store_hhhh;     break;
-        case skcms_PixelFormat_RGB_fff       >> 1: *ops++ = Op_store_fff;      break;
-        case skcms_PixelFormat_RGBA_ffff     >> 1: *ops++ = Op_store_ffff;     break;
-    }
-
-    void (*run)(const Op*, const void**, const char*, char*, int, size_t,size_t) = run_program;
-#if defined(TEST_FOR_HSW)
-    if (hsw_ok()) {
-        run = run_program_hsw;
-    }
-#endif
-    run(program, arguments, src, dst, n, src_bpp,dst_bpp);
-    return true;
-}
-
-static void assert_usable_as_destination(const skcms_ICCProfile* profile) {
-#if defined(NDEBUG)
-    (void)profile;
-#else
-    skcms_Matrix3x3 fromXYZD50;
-    skcms_TransferFunction invR, invG, invB;
-    assert(prep_for_destination(profile, &fromXYZD50, &invR, &invG, &invB));
-#endif
-}
-
-bool skcms_MakeUsableAsDestination(skcms_ICCProfile* profile) {
-    skcms_Matrix3x3 fromXYZD50;
-    if (!profile->has_trc || !profile->has_toXYZD50
-        || !skcms_Matrix3x3_invert(&profile->toXYZD50, &fromXYZD50)) {
-        return false;
-    }
-
-    skcms_TransferFunction tf[3];
-    for (int i = 0; i < 3; i++) {
-        skcms_TransferFunction inv;
-        if (profile->trc[i].table_entries == 0
-            && skcms_TransferFunction_invert(&profile->trc[i].parametric, &inv)) {
-            tf[i] = profile->trc[i].parametric;
-            continue;
-        }
-
-        float max_error;
-        // Parametric curves from skcms_ApproximateCurve() are guaranteed to be invertible.
-        if (!skcms_ApproximateCurve(&profile->trc[i], &tf[i], &max_error)) {
-            return false;
-        }
-    }
-
-    for (int i = 0; i < 3; ++i) {
-        profile->trc[i].table_entries = 0;
-        profile->trc[i].parametric = tf[i];
-    }
-
-    assert_usable_as_destination(profile);
-    return true;
-}
-
-bool skcms_MakeUsableAsDestinationWithSingleCurve(skcms_ICCProfile* profile) {
-    // Operate on a copy of profile, so we can choose the best TF for the original curves
-    skcms_ICCProfile result = *profile;
-    if (!skcms_MakeUsableAsDestination(&result)) {
-        return false;
-    }
-
-    int best_tf = 0;
-    float min_max_error = INFINITY_;
-    for (int i = 0; i < 3; i++) {
-        skcms_TransferFunction inv;
-        skcms_TransferFunction_invert(&result.trc[i].parametric, &inv);
-
-        float err = 0;
-        for (int j = 0; j < 3; ++j) {
-            err = fmaxf_(err, skcms_MaxRoundtripError(&profile->trc[j], &inv));
-        }
-        if (min_max_error > err) {
-            min_max_error = err;
-            best_tf = i;
-        }
-    }
-
-    for (int i = 0; i < 3; i++) {
-        result.trc[i].parametric = result.trc[best_tf].parametric;
-    }
-
-    *profile = result;
-    assert_usable_as_destination(profile);
-    return true;
-}
diff --git a/third_party/skcms/version.sha1 b/third_party/skcms/version.sha1
index f5367dddbc..e402cfbe8e 100755
--- a/third_party/skcms/version.sha1
+++ b/third_party/skcms/version.sha1
@@ -1 +1 @@
-14ea609fa6cae4cb61529e967a6bfae15a0a1c4d
\ No newline at end of file
+99b01c076f47cd7a5e7ab59aaae6ff941fa85816
\ No newline at end of file