Bug 1747299 - [UniqueBuffer] Use UniqueBuffer::Take instead of copy constructors for void*. r=gfx-reviewers,sotaro

Differential Revision: https://phabricator.services.mozilla.com/D134589

dom/canvas/TexUnpackBlob.cpp

@@ -450,7 +450,7 @@ bool TexUnpackBlob::ConvertIfNeeded(
     return false;
   }
 
-  UniqueBuffer dstBuffer = calloc(1u, (size_t)dstTotalBytes.value());
+  auto dstBuffer = UniqueBuffer::Take(calloc(1u, dstTotalBytes.value()));
   if (!dstBuffer.get()) {
     webgl->ErrorOutOfMemory("Failed to allocate dest buffer.");
     return false;

dom/canvas/WebGLBuffer.cpp

@@ -18,7 +18,7 @@ WebGLBuffer::~WebGLBuffer() {
   mByteLength = 0;
   mFetchInvalidator.InvalidateCaches();
 
-  mIndexCache = nullptr;
+  mIndexCache.reset();
   mIndexRanges.clear();
 
   if (!mContext) return;
@@ -105,7 +105,7 @@ void WebGLBuffer::BufferData(const GLenum target, const uint64_t size,
   const void* uploadData = maybeData;
   UniqueBuffer maybeCalloc;
   if (!uploadData) {
-    maybeCalloc = calloc(1, AssertedCast<size_t>(size));
+    maybeCalloc = UniqueBuffer::Take(calloc(1, AssertedCast<size_t>(size)));
     if (!maybeCalloc) {
       mContext->ErrorOutOfMemory("Failed to alloc zeros.");
       return;
@@ -117,7 +117,7 @@ void WebGLBuffer::BufferData(const GLenum target, const uint64_t size,
   UniqueBuffer newIndexCache;
   if (target == LOCAL_GL_ELEMENT_ARRAY_BUFFER &&
       mContext->mNeedsIndexValidation) {
-    newIndexCache = malloc(AssertedCast<size_t>(size));
+    newIndexCache = UniqueBuffer::Take(malloc(AssertedCast<size_t>(size)));
     if (!newIndexCache) {
       mContext->ErrorOutOfMemory("Failed to alloc index cache.");
       return;
@@ -148,7 +148,7 @@ void WebGLBuffer::BufferData(const GLenum target, const uint64_t size,
       // Truncate
       mByteLength = 0;
       mFetchInvalidator.InvalidateCaches();
-      mIndexCache = nullptr;
+      mIndexCache.reset();
       return;
     }
   } else {

dom/canvas/WebGLContextDraw.cpp

@@ -1086,7 +1086,7 @@ bool WebGLContext::DoFakeVertexAttrib0(const uint64_t vertexCount) {
 
   ////
 
-  const UniqueBuffer data(malloc(dataSize));
+  const auto data = UniqueBuffer::Take(malloc(dataSize));
   if (!data) {
     ErrorOutOfMemory("Failed to allocate fake vertex attrib 0 array.");
     return false;

dom/canvas/WebGLShader.cpp

@@ -24,9 +24,8 @@ static void PrintLongString(const char* const begin, const size_t len) {
   // internal size, so long strings are truncated.
 
   const size_t chunkSize = 1000;
-  const UniqueBuffer buf(moz_xmalloc(chunkSize + 1));  // +1 for null-term
-  const auto bufBegin = (char*)buf.get();
-  bufBegin[chunkSize] = '\0';
+  auto buf = std::vector<char>(chunkSize + 1);  // +1 for null-term
+  const auto bufBegin = buf.data();
 
   auto chunkBegin = begin;
   const auto end = begin + len;

dom/canvas/WebGLTexture.cpp

@@ -590,7 +590,7 @@ static bool ZeroTextureData(const WebGLContext* webgl, GLuint tex,
 
     const size_t sliceByteCount = checkedByteCount.value();
 
-    UniqueBuffer zeros = calloc(1u, sliceByteCount);
+    const auto zeros = UniqueBuffer::Take(calloc(1u, sliceByteCount));
     if (!zeros) return false;
 
     // Don't bother with striding it well.
@@ -635,7 +635,7 @@ static bool ZeroTextureData(const WebGLContext* webgl, GLuint tex,
 
   const size_t sliceByteCount = checkedByteCount.value();
 
-  UniqueBuffer zeros = calloc(1u, sliceByteCount);
+  const auto zeros = UniqueBuffer::Take(calloc(1u, sliceByteCount));
   if (!zeros) return false;
 
   // Don't bother with striding it well.

dom/canvas/WebGLTextureUpload.cpp

@@ -1709,7 +1709,7 @@ static bool DoCopyTexOrSubImage(WebGLContext* webgl, bool isSubImage,
       byteCount *= dstHeight;
 
       if (byteCount.isValid()) {
-        zeros = calloc(1u, byteCount.value());
+        zeros = UniqueBuffer::Take(calloc(1u, byteCount.value()));
       }
 
       if (!zeros.get()) {

dom/canvas/WebGLTypes.h

@@ -253,49 +253,29 @@ enum class WebGLExtensionID : uint8_t {
   Max
 };
 
-class UniqueBuffer {
+class UniqueBuffer final {
   // Like UniquePtr<>, but for void* and malloc/calloc/free.
-  void* mBuffer;
-
-  void reset() {
-  // Believe it or not, when `free` unconditional, it was showing up
-  // in profiles, nearly 20% of time spent in MethodDispatcther<UniformData>
-  // on Aquarium.
-    if (mBuffer) {
-      free(mBuffer);
-      mBuffer = nullptr;
-    }
-  }
-
+  void* mBuffer = nullptr;
 
  public:
-  static inline UniqueBuffer Alloc(const size_t byteSize) {
-    return {malloc(byteSize)};
+  static inline UniqueBuffer Take(void* buffer) {
+    UniqueBuffer ret;
+    ret.mBuffer = buffer;
+    return ret;
   }
 
-  UniqueBuffer() : mBuffer(nullptr) {}
-
-  MOZ_IMPLICIT UniqueBuffer(void* buffer) : mBuffer(buffer) {}
+  UniqueBuffer() = default;
 
   ~UniqueBuffer() {
     reset();
   }
 
-  UniqueBuffer(UniqueBuffer&& other) {
-    this->mBuffer = other.mBuffer;
-    other.mBuffer = nullptr;
-  }
+  UniqueBuffer(UniqueBuffer&& rhs) { *this = std::move(rhs); }
 
-  UniqueBuffer& operator=(UniqueBuffer&& other) {
+  UniqueBuffer& operator=(UniqueBuffer&& rhs) {
     reset();
-    this->mBuffer = other.mBuffer;
-    other.mBuffer = nullptr;
-    return *this;
-  }
-
-  UniqueBuffer& operator=(void* newBuffer) {
-    reset();
-    this->mBuffer = newBuffer;
+    this->mBuffer = rhs.mBuffer;
+    rhs.mBuffer = nullptr;
     return *this;
   }
 
@@ -303,10 +283,15 @@ class UniqueBuffer {
 
   void* get() const { return mBuffer; }
 
-  explicit UniqueBuffer(const UniqueBuffer& other) =
-      delete;  // construct using std::move()!
-  UniqueBuffer& operator=(const UniqueBuffer& other) =
-      delete;  // assign using std::move()!
+  void reset() {
+    // Believe it or not, when `free` unconditional, it was showing up
+    // in profiles, nearly 20% of time spent in MethodDispatcther<UniformData>
+    // on Aquarium.
+    if (mBuffer) {
+      free(mBuffer);
+      mBuffer = nullptr;
+    }
+  }
 };
 
 namespace webgl {