Reland 21502 - "Move OS::MemCopy and OS::MemMove out of platform to utils"

src/utils.cc

Index: src/utils.cc
diff --git a/src/utils.cc b/src/utils.cc
index 7af30f27b7bd57a395bf028aa97883d606423cb8..c159fc13ea7ca105549cc12464efd91527daab08 100644
--- a/src/utils.cc
+++ b/src/utils.cc
@@ -29,7 +29,7 @@ void SimpleStringBuilder::AddString(const char* s) {
 void SimpleStringBuilder::AddSubstring(const char* s, int n) {
   ASSERT(!is_finalized() && position_ + n <= buffer_.length());
   ASSERT(static_cast<size_t>(n) <= strlen(s));
-  OS::MemCopy(&buffer_[position_], s, n * kCharSize);
+  MemCopy(&buffer_[position_], s, n * kCharSize);
   position_ += n;
 }
 
@@ -145,12 +145,12 @@ char* ReadLine(const char* prompt) {
       char* new_result = NewArray<char>(new_len);
       // Copy the existing input into the new array and set the new
       // array as the result.
-      OS::MemCopy(new_result, result, offset * kCharSize);
+      MemCopy(new_result, result, offset * kCharSize);
       DeleteArray(result);
       result = new_result;
     }
     // Copy the newly read line into the result.
-    OS::MemCopy(result + offset, line_buf, len * kCharSize);
+    MemCopy(result + offset, line_buf, len * kCharSize);
     offset += len;
   }
   ASSERT(result != NULL);
@@ -314,4 +314,65 @@ void StringBuilder::AddFormattedList(const char* format, va_list list) {
 }
 
 
+#if V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_X87
+static void MemMoveWrapper(void* dest, const void* src, size_t size) {
+  memmove(dest, src, size);
+}
+
+
+// Initialize to library version so we can call this at any time during startup.
+static MemMoveFunction memmove_function = &MemMoveWrapper;
+
+// Defined in codegen-ia32.cc.
+MemMoveFunction CreateMemMoveFunction();
+
+// Copy memory area to disjoint memory area.
+void MemMove(void* dest, const void* src, size_t size) {
+  if (size == 0) return;
+  // Note: here we rely on dependent reads being ordered. This is true
+  // on all architectures we currently support.
+  (*memmove_function)(dest, src, size);
+}
+
+#elif V8_OS_POSIX && V8_HOST_ARCH_ARM
+void MemCopyUint16Uint8Wrapper(uint16_t* dest, const uint8_t* src,
+                               size_t chars) {
+  uint16_t* limit = dest + chars;
+  while (dest < limit) {
+    *dest++ = static_cast<uint16_t>(*src++);
+  }
+}
+
+
+MemCopyUint8Function memcopy_uint8_function = &MemCopyUint8Wrapper;
+MemCopyUint16Uint8Function memcopy_uint16_uint8_function =
+    &MemCopyUint16Uint8Wrapper;
+// Defined in codegen-arm.cc.
+MemCopyUint8Function CreateMemCopyUint8Function(MemCopyUint8Function stub);
+MemCopyUint16Uint8Function CreateMemCopyUint16Uint8Function(
+    MemCopyUint16Uint8Function stub);
+
+#elif V8_OS_POSIX && V8_HOST_ARCH_MIPS
+MemCopyUint8Function memcopy_uint8_function = &MemCopyUint8Wrapper;
+// Defined in codegen-mips.cc.
+MemCopyUint8Function CreateMemCopyUint8Function(MemCopyUint8Function stub);
+#endif
+
+
+void init_memcopy_functions() {
+#if V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_X87
+  MemMoveFunction generated_memmove = CreateMemMoveFunction();
+  if (generated_memmove != NULL) {
+    memmove_function = generated_memmove;
+  }
+#elif V8_OS_POSIX && V8_HOST_ARCH_ARM
+  memcopy_uint8_function = CreateMemCopyUint8Function(&MemCopyUint8Wrapper);
+  memcopy_uint16_uint8_function =
+      CreateMemCopyUint16Uint8Function(&MemCopyUint16Uint8Wrapper);
+#elif V8_OS_POSIX && V8_HOST_ARCH_MIPS
+  memcopy_uint8_function = CreateMemCopyUint8Function(&MemCopyUint8Wrapper);
+#endif
+}
+
+
 } }  // namespace v8::internal