Assembler changes for enabling GrowHeap in Wasm

src/x64/assembler-x64.h

Index: src/x64/assembler-x64.h
diff --git a/src/x64/assembler-x64.h b/src/x64/assembler-x64.h
index 0ce714db0915fa077e943853ede217ce6c69babc..1a183c06cf37ed9876b98714dc7f33c042daf74e 100644
--- a/src/x64/assembler-x64.h
+++ b/src/x64/assembler-x64.h
@@ -334,13 +334,18 @@ enum RoundingMode {
 class Immediate BASE_EMBEDDED {
  public:
   explicit Immediate(int32_t value) : value_(value) {}
+  explicit Immediate(int32_t value, RelocInfo::Mode rmode)

[titzer, 2016/03/14 15:23:38]

AFAICT we don't need this until we have updateable lengths, which will be 32 bit
quantities. Can we do this change in a separate CL?

[gdeepti1, 2016/03/14 20:08:14]

Sounds good, removed from this CL. 

+      : value_(value), rmode_(rmode) {}
   explicit Immediate(Smi* value) {
     DCHECK(SmiValuesAre31Bits());  // Only available for 31-bit SMI.
     value_ = static_cast<int32_t>(reinterpret_cast<intptr_t>(value));
   }
 
+  RelocInfo::Mode rmode() { return rmode_; }
+
  private:
   int32_t value_;
+  RelocInfo::Mode rmode_ = RelocInfo::NONE32;
 
   friend class Assembler;
 };
@@ -699,8 +704,10 @@ class Assembler : public AssemblerBase {
   void movp(Register dst, void* ptr, RelocInfo::Mode rmode);
 
   // Loads a 64-bit immediate into a register.
-  void movq(Register dst, int64_t value);
-  void movq(Register dst, uint64_t value);
+  void movq(Register dst, int64_t value,
+            RelocInfo::Mode rmode = RelocInfo::NONE64);
+  void movq(Register dst, uint64_t value,
+            RelocInfo::Mode rmode = RelocInfo::NONE64);
 
   void movsxbl(Register dst, Register src);
   void movsxbl(Register dst, const Operand& src);
@@ -1744,7 +1751,12 @@ class Assembler : public AssemblerBase {
                                RelocInfo::Mode rmode,
                                TypeFeedbackId ast_id = TypeFeedbackId::None());
   inline void emit_runtime_entry(Address entry, RelocInfo::Mode rmode);
-  void emit(Immediate x) { emitl(x.value_); }
+  void emit(Immediate x) {
+    if (!RelocInfo::IsNone(x.rmode_)) {
+      RecordRelocInfo(x.rmode_);
+    }
+    emitl(x.value_);
+  }
 
   // Emits a REX prefix that encodes a 64-bit operand size and
   // the top bit of both register codes.