Use a fixed input register where we require a byte register.

Currently we can't specify a set of registers as a register constraint.
This change forces a fixed register (eax) in places that need
a byte register.

BUG=77752
Review URL: http://codereview.chromium.org/6708109

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7417 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/lithium-ia32.cc

@@ -1905,7 +1905,6 @@ LInstruction* LChunkBuilder::DoStoreKeyedSpecializedArrayElement(
   ASSERT(instr->key()->representation().IsInteger32());
 
   LOperand* external_pointer = UseRegister(instr->external_pointer());
-  LOperand* val = UseRegister(instr->value());
   LOperand* key = UseRegister(instr->key());
   LOperand* temp = NULL;
 
@@ -1916,6 +1915,15 @@ LInstruction* LChunkBuilder::DoStoreKeyedSpecializedArrayElement(
     temp = FixedTemp(eax);
   }
 
+  LOperand* val = NULL;
+  if (array_type == kExternalByteArray ||
+      array_type == kExternalUnsignedByteArray) {
+    // We need a byte register in this case for the value.
+    val = UseFixed(instr->value(), eax);
+  } else {
+    val = UseRegister(instr->value());
+  }
+
   return new LStoreKeyedSpecializedArrayElement(external_pointer,
                                                 key,
                                                 val,