Bug 1462544 - Use <algorithm> functions to fill and copy data in Bitmap.* rather than PodOperations.h functions. r=jandem

--HG--
extra : rebase_source : 3e96b8528ffe20339186c9c1363214fa2ddc7539

js/src/ds/Bitmap.cpp

@@ -6,6 +6,8 @@
 
 #include "ds/Bitmap.h"
 
+#include <algorithm>
+
 using namespace js;
 
 SparseBitmap::~SparseBitmap()
@@ -33,7 +35,7 @@ SparseBitmap::createBlock(Data::AddPtr p, size_t blockId)
     BitBlock* block = js_new<BitBlock>();
     if (!block || !data.add(p, blockId, block))
         oomUnsafe.crash("Bitmap OOM");
-    PodZero(block);
+    std::fill(block->begin(), block->end(), 0);
     return *block;
 }
 

js/src/ds/Bitmap.h

@@ -11,7 +11,6 @@
 #include "mozilla/Assertions.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/MemoryChecking.h"
-#include "mozilla/PodOperations.h"
 
 #include <algorithm>
 #include <stddef.h>
@@ -54,7 +53,9 @@ class DenseBitmap
 
     void copyBitsFrom(size_t wordStart, size_t numWords, uintptr_t* source) {
         MOZ_ASSERT(wordStart + numWords <= data.length());
-        mozilla::PodCopy(&data[wordStart], source, numWords);
+        // Use std::copy and not std::copy_n because the former requires no
+        // overlap and so provides extra opportunity to optimize.
+        std::copy(source, source + numWords, &data[wordStart]);
     }
 
     void bitwiseOrRangeInto(size_t wordStart, size_t numWords, uintptr_t* target) const {