Use simple buffers instead of vectors

Start using simple buffers, these will be used for
multiple runs latter on.

Change-Id: Iab0559d5a47eb5e54254a985051d5d25a91be69f
Reviewed-on: https://skia-review.googlesource.com/140791
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>

4 files changed, 65 insertions, 34 deletions

diff --git a/src/core/SkGlyphCache.cpp b/src/core/SkGlyphCache.cpp
index 61e01af894..30f7def312 100644
--- a/src/core/SkGlyphCache.cpp
+++ b/src/core/SkGlyphCache.cpp
@@ -131,9 +131,9 @@ const SkGlyph& SkGlyphCache::getGlyphIDMetrics(uint16_t glyphID, SkFixed x, SkFi
 }
 
 void SkGlyphCache::getAdvances(SkSpan<const SkGlyphID> glyphIDs, SkPoint advances[]) {
-    for (ptrdiff_t i = 0; i < glyphIDs.size(); i++) {
-        auto glyph = this->getGlyphIDAdvance(glyphIDs[i]);
-        advances[i] = SkPoint::Make(glyph.fAdvanceX, glyph.fAdvanceY);
+    for (auto glyphID : glyphIDs) {
+        auto glyph = this->getGlyphIDAdvance(glyphID);
+        *advances++ = SkPoint::Make(glyph.fAdvanceX, glyph.fAdvanceY);
     }
 }
 
diff --git a/src/core/SkGlyphRun.cpp b/src/core/SkGlyphRun.cpp
index 87274d4def..3bd9efc90f 100644
--- a/src/core/SkGlyphRun.cpp
+++ b/src/core/SkGlyphRun.cpp
@@ -91,7 +91,7 @@ SkSpan<const SkGlyphID> SkGlyphIDSet::uniquifyGlyphIDs(
         // If the following bzero becomes a performance problem, the memory can be marked as
         // initialized for valgrind and msan.
         // valgrind = VALGRIND_MAKE_MEM_DEFINED(fUniverseToUnique, universeSize * sizeof(SkGlyphID))
-        // msan = sk_msan_assert_initialized(fUniverseToUnique, universeSize * sizeof(SkGlyphID))
+        // msan = sk_msan_mark_initialized(fUniverseToUnique, universeSize * sizeof(SkGlyphID))
         sk_bzero(fUniverseToUnique, universeSize * sizeof(SkGlyphID));
     }
 
@@ -168,10 +168,12 @@ SkGlyphRun* SkGlyphRunBuilder::useGlyphRun() {
 void SkGlyphRunBuilder::initialize(size_t totalRunSize) {
     fUniqueID = 0;
 
-    // Using resize is temporary until simpler buffers are in place.
-    fDenseIndex.resize(totalRunSize);
-    fPositions.resize(totalRunSize);
-    fUniqueGlyphIDs.resize(totalRunSize);
+    if (totalRunSize > fMaxTotalRunSize) {
+        fMaxTotalRunSize = totalRunSize;
+        fUniqueGlyphIDIndices.reset(fMaxTotalRunSize);
+        fPositions.reset(fMaxTotalRunSize);
+        fUniqueGlyphIDs.reset(fMaxTotalRunSize);
+    }
 
     // Be sure to clean up the last run before we reuse it.
     fScratchGlyphRun.~SkGlyphRun();
@@ -207,7 +209,7 @@ SkSpan<const SkGlyphID> SkGlyphRunBuilder::addDenseAndUnique(
         // There better be glyphs in the font if we want to uniqify.
         if (glyphUniverseSize > 0) {
             uniquifiedGlyphIDs = fGlyphIDSet.uniquifyGlyphIDs(
-                    glyphUniverseSize, glyphIDs, fUniqueGlyphIDs.data(), fDenseIndex.data());
+                    glyphUniverseSize, glyphIDs, fUniqueGlyphIDs, fUniqueGlyphIDIndices);
         }
     }
 
@@ -218,21 +220,23 @@ void SkGlyphRunBuilder::makeGlyphRun(
         const SkPaint& runPaint,
         SkSpan<const SkGlyphID> glyphIDs,
         SkSpan<const SkPoint> positions,
+        SkSpan<const uint16_t> uniqueGlyphIDIndices,
+        SkSpan<const SkGlyphID> uniqueGlyphIDs,
         SkSpan<const char> text,
         SkSpan<const uint32_t> clusters) {
 
     // Ignore empty runs.
-    if (!fDenseIndex.empty()) {
+    if (!glyphIDs.empty()) {
         SkPaint glyphRunPaint{runPaint};
         glyphRunPaint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
         glyphRunPaint.setTextAlign(SkPaint::kLeft_Align);
 
         new ((void*)&fScratchGlyphRun) SkGlyphRun{
                 std::move(glyphRunPaint),
-                SkSpan<const uint16_t>{fDenseIndex},
+                uniqueGlyphIDIndices,
                 positions,
                 glyphIDs,
-                SkSpan<const SkGlyphID>{fUniqueGlyphIDs},
+                uniqueGlyphIDs,
                 text,
                 clusters
         };
@@ -244,10 +248,12 @@ void SkGlyphRunBuilder::drawText(
         SkSpan<const char> text, SkSpan<const uint32_t> clusters) {
     SkASSERT(!glyphIDs.empty());
 
+    auto runSize = glyphIDs.size();
+
     auto unqiueGlyphIDs = this->addDenseAndUnique(paint, glyphIDs);
 
     if (!unqiueGlyphIDs.empty()) {
-        fScratchAdvances.resize(fUniqueGlyphIDs.size());
+        fScratchAdvances.resize(runSize);
         {
             auto cache = SkStrikeCache::FindOrCreateStrikeExclusive(paint);
             cache->getAdvances(unqiueGlyphIDs, fScratchAdvances.data());
@@ -255,9 +261,9 @@ void SkGlyphRunBuilder::drawText(
 
         SkPoint endOfLastGlyph = origin;
 
-        for (size_t i = 0; i < fDenseIndex.size(); i++) {
+        for (size_t i = 0; i < runSize; i++) {
             fPositions[i] = endOfLastGlyph;
-            endOfLastGlyph += fScratchAdvances[fDenseIndex[i]];
+            endOfLastGlyph += fScratchAdvances[fUniqueGlyphIDIndices[i]];
         }
 
         if (paint.getTextAlign() != SkPaint::kLeft_Align) {
@@ -265,12 +271,20 @@ void SkGlyphRunBuilder::drawText(
             if (paint.getTextAlign() == SkPaint::kCenter_Align) {
                 len.scale(SK_ScalarHalf);
             }
-            for (size_t i = 0; i < fDenseIndex.size(); i++) {
-                fPositions[i] -= len;
+            for (auto& pt : SkSpan<SkPoint>{fPositions, runSize}) {
+                pt -= len;
             }
         }
 
-        this->makeGlyphRun(paint, glyphIDs, SkSpan<const SkPoint>{fPositions}, text, clusters);
+
+        this->makeGlyphRun(
+                paint,
+                glyphIDs,
+                SkSpan<const SkPoint>{fPositions, runSize},
+                SkSpan<const uint16_t>{fUniqueGlyphIDIndices, runSize},
+                unqiueGlyphIDs,
+                text,
+                clusters);
     }
 }
 
@@ -278,6 +292,7 @@ void SkGlyphRunBuilder::drawPosTextH(const SkPaint& paint, SkSpan<const SkGlyphI
                                      const SkScalar* xpos, SkScalar constY,
                                      SkSpan<const char> text, SkSpan<const uint32_t> clusters) {
     SkASSERT(!glyphIDs.empty());
+    auto runSize = glyphIDs.size();
 
     // The dense indices are not used by the rest of the stack yet.
     #ifdef SK_DEBUG
@@ -286,17 +301,26 @@ void SkGlyphRunBuilder::drawPosTextH(const SkPaint& paint, SkSpan<const SkGlyphI
 
     // TODO: when using the unique glyph system have a guard that there are actually glyphs like
     // drawText above.
-    for (size_t i = 0; i < fDenseIndex.size(); i++) {
-        fPositions[i] = SkPoint::Make(xpos[i], constY);
+    auto posCursor = fPositions.get();
+    for (auto x : SkSpan<const SkScalar>{xpos, runSize}) {
+        *posCursor++ = SkPoint::Make(x, constY);
     }
 
-    this->makeGlyphRun(paint, glyphIDs, SkSpan<const SkPoint>{fPositions}, text, clusters);
+    this->makeGlyphRun(
+            paint,
+            glyphIDs,
+            SkSpan<const SkPoint>{fPositions, runSize},
+            SkSpan<const uint16_t>{},
+            SkSpan<const SkGlyphID>{},
+            text,
+            clusters);
 }
 
 void SkGlyphRunBuilder::drawPosText(const SkPaint& paint, SkSpan<const SkGlyphID> glyphIDs,
                                     const SkPoint* pos,
                                     SkSpan<const char> text, SkSpan<const uint32_t> clusters) {
     SkASSERT(!glyphIDs.empty());
+    auto runSize = glyphIDs.size();
 
     // The dense indices are not used by the rest of the stack yet.
     #ifdef SK_DEBUG
@@ -305,11 +329,14 @@ void SkGlyphRunBuilder::drawPosText(const SkPaint& paint, SkSpan<const SkGlyphID
 
     // TODO: when using the unique glyph system have a guard that there are actually glyphs like
     // drawText above.
-    for (size_t i = 0; i < fDenseIndex.size(); i++) {
-        fPositions[i] = pos[i];
-    }
-
-    this->makeGlyphRun(paint, glyphIDs, SkSpan<const SkPoint>{fPositions}, text, clusters);
+    this->makeGlyphRun(
+            paint,
+            glyphIDs,
+            SkSpan<const SkPoint>{pos, runSize},
+            SkSpan<const uint16_t>{},
+            SkSpan<const SkGlyphID>{},
+            text,
+            clusters);
 }
 
 
diff --git a/src/core/SkGlyphRun.h b/src/core/SkGlyphRun.h
index 7c3a74860c..affc044f76 100644
--- a/src/core/SkGlyphRun.h
+++ b/src/core/SkGlyphRun.h
@@ -24,23 +24,23 @@ template <typename T>
 class SkSpan {
 public:
     SkSpan() : fPtr{nullptr}, fSize{0} {}
-    SkSpan(T* ptr, ptrdiff_t size) : fPtr{ptr}, fSize{size} { SkASSERT(size >= 0); }
+    SkSpan(T* ptr, size_t size) : fPtr{ptr}, fSize{size} { }
     template <typename U>
-    explicit SkSpan(std::vector<U>& v) : fPtr{v.data()}, fSize{SkTo<ptrdiff_t>(v.size())} {}
+    explicit SkSpan(std::vector<U>& v) : fPtr{v.data()}, fSize{v.size()} {}
     SkSpan(const SkSpan<T>& o) = default;
     SkSpan& operator=( const SkSpan& other ) = default;
-    T& operator [] (ptrdiff_t i) const { return fPtr[i]; }
+    T& operator [] (size_t i) const { return fPtr[i]; }
     T* begin() const { return fPtr; }
     T* end() const { return fPtr + fSize; }
     const T* cbegin() const { return fPtr; }
     const T* cend() const { return fPtr + fSize; }
     T* data() const { return fPtr; }
-    ptrdiff_t size() const { return fSize; }
+    size_t size() const { return fSize; }
     bool empty() const { return fSize == 0; }
 
 private:
     T* fPtr;
-    ptrdiff_t fSize;
+    size_t fSize;
 };
 
 class SkGlyphRun {
@@ -120,6 +120,8 @@ private:
             const SkPaint& runPaint,
             SkSpan<const SkGlyphID> glyphIDs,
             SkSpan<const SkPoint> positions,
+            SkSpan<const uint16_t> uniqueGlyphIDIndices,
+            SkSpan<const SkGlyphID> uniqueGlyphIDs,
             SkSpan<const char> text,
             SkSpan<const uint32_t> clusters);
 
@@ -136,9 +138,10 @@ private:
 
     uint64_t fUniqueID{0};
 
-    std::vector<uint16_t> fDenseIndex;
-    std::vector<SkPoint> fPositions;
-    std::vector<SkGlyphID> fUniqueGlyphIDs;
+    size_t fMaxTotalRunSize{0};
+    SkAutoTMalloc<uint16_t> fUniqueGlyphIDIndices;
+    SkAutoTMalloc<SkPoint> fPositions;
+    SkAutoTMalloc<SkGlyphID> fUniqueGlyphIDs;
 
     // Used as a temporary for preparing using utfN text. This implies that only one run of
     // glyph ids will ever be needed because blobs are already glyph based.
diff --git a/src/core/SkStrikeCache.cpp b/src/core/SkStrikeCache.cpp
index 94f8c6d8bd..47b3c9bf8b 100644
--- a/src/core/SkStrikeCache.cpp
+++ b/src/core/SkStrikeCache.cpp
@@ -12,6 +12,7 @@
 #include "SkGlyphCache.h"
 #include "SkGraphics.h"
 #include "SkMutex.h"
+#include "SkTemplates.h"
 #include "SkTraceMemoryDump.h"
 #include "SkTypeface.h"
 #include "SkPaintPriv.h"