[compiler] Add relocatable pointer constants for wasm memory references.

src/compiler/x64/code-generator-x64.cc

Index: src/compiler/x64/code-generator-x64.cc
diff --git a/src/compiler/x64/code-generator-x64.cc b/src/compiler/x64/code-generator-x64.cc
index d9c5d60fb9b06f16431adb208cb648e4ec4da32f..30b0f9dce62343a590dd93225800537e24460013 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -2078,17 +2078,25 @@ void CodeGenerator::AssembleMove(InstructionOperand* source,
                                                : kScratchRegister;
       switch (src.type()) {
         case Constant::kInt32: {
-          // TODO(dcarney): don't need scratch in this case.
-          int32_t value = src.ToInt32();
-          if (value == 0) {
-            __ xorl(dst, dst);
+          if (src.rmode() == RelocInfo::WASM_MEMORY_REFERENCE) {
+            __ movq(dst, src.ToInt64(), src.rmode());
           } else {
-            __ movl(dst, Immediate(value));
+            // TODO(dcarney): don't need scratch in this case.
+            int32_t value = src.ToInt32();
+            if (value == 0) {
+              __ xorl(dst, dst);
+            } else {
+              __ movl(dst, Immediate(value));
+            }
           }
           break;
         }
         case Constant::kInt64:
-          __ Set(dst, src.ToInt64());
+          if (src.rmode() == RelocInfo::WASM_MEMORY_REFERENCE) {
+            __ movq(dst, src.ToInt64(), src.rmode());
+          } else {
+            __ Set(dst, src.ToInt64());
+          }
           break;
         case Constant::kFloat32:
           __ Move(dst,