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-rw-r--r--include/core/SkClampRange.h3
-rw-r--r--src/core/SkClampRange.cpp91
-rw-r--r--src/effects/SkGradientShader.cpp26
-rw-r--r--tests/ClampRangeTest.cpp84
4 files changed, 154 insertions, 50 deletions
diff --git a/include/core/SkClampRange.h b/include/core/SkClampRange.h
index 999faa0ae9..9acf1ad5c5 100644
--- a/include/core/SkClampRange.h
+++ b/include/core/SkClampRange.h
@@ -37,6 +37,9 @@ struct SkClampRange {
bool fOverflowed; // true if we had to clamp due to numerical overflow
void init(SkFixed fx, SkFixed dx, int count, int v0, int v1);
+
+private:
+ void initFor1(SkFixed fx);
};
#endif
diff --git a/src/core/SkClampRange.cpp b/src/core/SkClampRange.cpp
index be41067f23..32ea96429e 100644
--- a/src/core/SkClampRange.cpp
+++ b/src/core/SkClampRange.cpp
@@ -20,7 +20,7 @@
* returns [0..count] for the number of steps (<= count) for which x0 <= edge
* given each step is followed by x0 += dx
*/
-static int chop(SkFixed x0, SkFixed edge, SkFixed x1, SkFixed dx, int count) {
+static int chop(int64_t x0, SkFixed edge, int64_t x1, int64_t dx, int count) {
SkASSERT(dx > 0);
SkASSERT(count >= 0);
@@ -30,36 +30,52 @@ static int chop(SkFixed x0, SkFixed edge, SkFixed x1, SkFixed dx, int count) {
if (x1 <= edge) {
return count;
}
- int n = (edge - x0 + dx - 1) / dx;
+ int64_t n = (edge - x0 + dx - 1) / dx;
SkASSERT(n >= 0);
SkASSERT(n <= count);
- return n;
+ return (int)n;
}
-void SkClampRange::init(SkFixed fx, SkFixed dx, int count, int v0, int v1) {
+static bool overflows_fixed(int64_t x) {
+ return x < -SK_FixedMax || x > SK_FixedMax;
+}
+
+void SkClampRange::initFor1(SkFixed fx) {
+ fCount0 = fCount1 = fCount2 = 0;
+ if (fx <= 0) {
+ fCount0 = 1;
+ } else if (fx < 0xFFFF) {
+ fCount1 = 1;
+ fFx1 = fx;
+ } else {
+ fCount2 = 1;
+ }
+}
+
+void SkClampRange::init(SkFixed fx0, SkFixed dx0, int count, int v0, int v1) {
SkASSERT(count > 0);
fV0 = v0;
fV1 = v1;
+ fOverflowed = false;
- // check for over/underflow
- {
- int64_t eex = (int64_t)fx + count * (int64_t)dx;
- if (eex > SK_FixedMax) {
-
- } else if (eex < -SK_FixedMax) {
- }
+ // special case 1 == count, as it is slightly common for skia
+ // and avoids us ever calling divide or 64bit multiply
+ if (1 == count) {
+ this->initFor1(fx0);
+ return;
}
- // remember our original fx
- const SkFixed fx0 = fx;
+ int64_t fx = fx0;
+ int64_t dx = dx0;
// start with ex equal to the last computed value
- SkFixed ex = fx + (count - 1) * dx;
+ int64_t ex = fx + (count - 1) * dx;
+ fOverflowed = overflows_fixed(ex);
- if ((unsigned)(fx | ex) <= 0xFFFF) {
+ if ((uint64_t)(fx | ex) <= 0xFFFF) {
fCount0 = fCount2 = 0;
fCount1 = count;
- fFx1 = fx;
+ fFx1 = fx0;
return;
}
if (fx <= 0 && ex <= 0) {
@@ -73,9 +89,41 @@ void SkClampRange::init(SkFixed fx, SkFixed dx, int count, int v0, int v1) {
return;
}
+ int extraCount = 0;
+
// now make ex be 1 past the last computed value
ex += dx;
-
+ fOverflowed = overflows_fixed(ex);
+ // now check for over/under flow
+ if (fOverflowed) {
+ int originalCount = count;
+ int64_t ccount;
+ bool swap = dx < 0;
+ if (swap) {
+ dx = -dx;
+ fx = -fx;
+ }
+ ccount = (SK_FixedMax - fx + dx - 1) / dx;
+ if (swap) {
+ dx = -dx;
+ fx = -fx;
+ }
+ SkASSERT(ccount > 0 && ccount <= SK_FixedMax);
+
+ count = (int)ccount;
+ if (0 == count) {
+ this->initFor1(fx0);
+ if (dx > 0) {
+ fCount2 += originalCount - 1;
+ } else {
+ fCount0 += originalCount - 1;
+ }
+ return;
+ }
+ extraCount = originalCount - count;
+ ex = fx + dx * count;
+ }
+
bool doSwap = dx < 0;
if (doSwap) {
@@ -85,6 +133,7 @@ void SkClampRange::init(SkFixed fx, SkFixed dx, int count, int v0, int v1) {
dx = -dx;
}
+
fCount0 = chop(fx, 0, ex, dx, count);
count -= fCount0;
fx += fCount0 * dx;
@@ -112,7 +161,13 @@ void SkClampRange::init(SkFixed fx, SkFixed dx, int count, int v0, int v1) {
}
if (fCount1 > 0) {
- fFx1 = fx0 + fCount0 * dx;
+ fFx1 = fx0 + fCount0 * (int)dx;
+ }
+
+ if (dx > 0) {
+ fCount2 += extraCount;
+ } else {
+ fCount0 += extraCount;
}
}
diff --git a/src/effects/SkGradientShader.cpp b/src/effects/SkGradientShader.cpp
index 068913f03f..5af04862f2 100644
--- a/src/effects/SkGradientShader.cpp
+++ b/src/effects/SkGradientShader.cpp
@@ -27,7 +27,7 @@
#define USE_DITHER_32BIT_GRADIENT
#endif
-//#define SK_ENABLE_FAST_LINEAR_GRADIENTS
+#define SK_ENABLE_FAST_LINEAR_GRADIENTS
#ifdef SK_ENABLE_FAST_LINEAR_GRADIENTS
static void sk_memset32_dither(uint32_t dst[], uint32_t v0, uint32_t v1,
@@ -819,11 +819,13 @@ static inline bool no_need_for_clamp(int fx, int dx, int count) {
#include "SkClampRange.h"
#define NO_CHECK_ITER \
- fi = fx >> 8; \
+ do { \
+ unsigned fi = fx >> 8; \
SkASSERT(fi <= 0xFF); \
fx += dx; \
*dstC++ = cache[toggle + fi]; \
- toggle ^= TOGGLE_MASK
+ toggle ^= TOGGLE_MASK; \
+ } while (0)
void Linear_Gradient::shadeSpan(int x, int y, SkPMColor dstC[], int count) {
@@ -874,9 +876,9 @@ void Linear_Gradient::shadeSpan(int x, int y, SkPMColor dstC[], int count) {
dstC += count;
}
if ((count = range.fCount1) > 0) {
- unsigned fi;
- int i, unroll = count >> 3;
- for (i = 0; i < unroll; i++) {
+ int unroll = count >> 3;
+ fx = range.fFx1;
+ for (int i = 0; i < unroll; i++) {
NO_CHECK_ITER; NO_CHECK_ITER;
NO_CHECK_ITER; NO_CHECK_ITER;
NO_CHECK_ITER; NO_CHECK_ITER;
@@ -978,11 +980,13 @@ static void dither_memset16(uint16_t dst[], uint16_t value, uint16_t other,
}
#define NO_CHECK_ITER_16 \
- fi = fx >> kCache16Shift; \
+ do { \
+ unsigned fi = fx >> kCache16Shift; \
SkASSERT(fi <= kCache16Mask); \
fx += dx; \
*dstC++ = cache[toggle + fi]; \
- toggle ^= TOGGLE_MASK
+ toggle ^= TOGGLE_MASK; \
+ } while (0)
void Linear_Gradient::shadeSpan16(int x, int y, uint16_t dstC[], int count) {
@@ -1028,9 +1032,9 @@ void Linear_Gradient::shadeSpan16(int x, int y, uint16_t dstC[], int count) {
dstC += count;
}
if ((count = range.fCount1) > 0) {
- unsigned fi;
- int i, unroll = count >> 3;
- for (i = 0; i < unroll; i++) {
+ int unroll = count >> 3;
+ fx = range.fFx1;
+ for (int i = 0; i < unroll; i++) {
NO_CHECK_ITER_16; NO_CHECK_ITER_16;
NO_CHECK_ITER_16; NO_CHECK_ITER_16;
NO_CHECK_ITER_16; NO_CHECK_ITER_16;
diff --git a/tests/ClampRangeTest.cpp b/tests/ClampRangeTest.cpp
index b3d1e78a90..be9c6ec903 100644
--- a/tests/ClampRangeTest.cpp
+++ b/tests/ClampRangeTest.cpp
@@ -4,6 +4,27 @@
static skiatest::Reporter* gReporter;
+static void debug_me() {
+ if (NULL == gReporter) {
+ SkDebugf("dsfdssd\n");
+ }
+}
+
+#ifdef USE_REPORTER
+
+#define R_ASSERT(cond) \
+ do { if (!(cond)) { \
+ debug_me(); \
+ REPORTER_ASSERT(gReporter, cond); \
+ }} while (0)
+
+#else
+#define R_ASSERT(cond) \
+ do { if (!(cond)) { \
+ debug_me(); \
+ }} while (0)
+#endif
+
static int classify_value(SkFixed fx, int v0, int v1) {
if (fx <= 0) {
return v0;
@@ -11,7 +32,7 @@ static int classify_value(SkFixed fx, int v0, int v1) {
if (fx >= 0xFFFF) {
return v1;
}
- REPORTER_ASSERT(gReporter, false);
+ R_ASSERT(false);
return 0;
}
@@ -21,22 +42,34 @@ static int classify_value(SkFixed fx, int v0, int v1) {
static void slow_check(const SkClampRange& range,
SkFixed fx, SkFixed dx, int count) {
SkASSERT(range.fCount0 + range.fCount1 + range.fCount2 == count);
-
+
int i;
- for (i = 0; i < range.fCount0; i++) {
- int v = classify_value(fx, V0, V1);
- REPORTER_ASSERT(gReporter, v == range.fV0);
- fx += dx;
- }
- REPORTER_ASSERT(gReporter, range.fCount1 == 0 || fx == range.fFx1);
- for (i = 0; i < range.fCount1; i++) {
- REPORTER_ASSERT(gReporter, fx >= 0 && fx <= 0xFFFF);
- fx += dx;
- }
- for (i = 0; i < range.fCount2; i++) {
- int v = classify_value(fx, V0, V1);
- REPORTER_ASSERT(gReporter, v == range.fV1);
- fx += dx;
+ if (range.fOverflowed) {
+ fx = range.fFx1;
+ for (i = 0; i < range.fCount1; i++) {
+ R_ASSERT(fx >= 0 && fx <= 0xFFFF);
+ fx += dx;
+ }
+ } else {
+ for (i = 0; i < range.fCount0; i++) {
+ int v = classify_value(fx, V0, V1);
+ R_ASSERT(v == range.fV0);
+ fx += dx;
+ }
+ if (range.fCount1 > 0 && fx != range.fFx1) {
+ SkDebugf("%x %x\n", fx, range.fFx1);
+ R_ASSERT(!"bad fFx1");
+ return;
+ }
+ for (i = 0; i < range.fCount1; i++) {
+ R_ASSERT(fx >= 0 && fx <= 0xFFFF);
+ fx += dx;
+ }
+ for (i = 0; i < range.fCount2; i++) {
+ int v = classify_value(fx, V0, V1);
+ R_ASSERT(v == range.fV1);
+ fx += dx;
+ }
}
}
@@ -48,7 +81,8 @@ static void test_range(SkFixed fx, SkFixed dx, int count) {
#define ff(x) SkIntToFixed(x)
-static void TestClampRange(skiatest::Reporter* reporter) {
+void TestClampRange(skiatest::Reporter* reporter);
+void TestClampRange(skiatest::Reporter* reporter) {
gReporter = reporter;
test_range(0, 0, 20);
@@ -60,7 +94,12 @@ static void TestClampRange(skiatest::Reporter* reporter) {
test_range(10, -1, 20);
test_range(-10, 3, 20);
test_range(10, -3, 20);
-
+
+ test_range(ff(1), ff(16384), 100);
+ test_range(ff(-1), ff(-16384), 100);
+ test_range(ff(1)/2, ff(16384), 100);
+ test_range(ff(1)/2, ff(-16384), 100);
+
SkRandom rand;
// test non-overflow cases
@@ -73,14 +112,17 @@ static void TestClampRange(skiatest::Reporter* reporter) {
}
// test overflow cases
- for (int i = 0; i < 0*1000000; i++) {
+ for (int i = 0; i < 100000; i++) {
SkFixed fx = rand.nextS();
- SkFixed sx = rand.nextS();
+ SkFixed dx = rand.nextS();
int count = rand.nextU() % 1000 + 1;
- SkFixed dx = (sx - fx) / count;
test_range(fx, dx, count);
}
}
+#ifdef USE_REPORTER
+
#include "TestClassDef.h"
DEFINE_TESTCLASS("ClampRange", ClampRangeClass, TestClampRange)
+
+#endif
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-02 16:49:33 +0000