Assembler changes for enabling GrowHeap in Wasm

src/arm/assembler-arm-inl.h

Index: src/arm/assembler-arm-inl.h
diff --git a/src/arm/assembler-arm-inl.h b/src/arm/assembler-arm-inl.h
index 0de96428f33789b66d76d5a1293af8a7276d844d..1e97a3d7606631c298142728c4ef557db33e92db 100644
--- a/src/arm/assembler-arm-inl.h
+++ b/src/arm/assembler-arm-inl.h
@@ -71,6 +71,10 @@ Address RelocInfo::target_address() {
   return Assembler::target_address_at(pc_, host_);
 }
 
+Address RelocInfo::wasm_memory_reference() {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  return Assembler::target_address_at(pc_, host_);
+}
 
 Address RelocInfo::target_address_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
@@ -114,6 +118,19 @@ void RelocInfo::set_target_address(Address target,
   }
 }
 
+void RelocInfo::update_wasm_memory_reference(
+    Address old_base, Address new_base, size_t old_size, size_t new_size,
+    ICacheFlushMode icache_flush_mode) {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  DCHECK(old_size <= new_size);

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

No need to assert this, I think.

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

Done.

+  DCHECK(old_base <= wasm_memory_reference() &&
+         wasm_memory_reference() <= old_base + old_size);
+  Address updated_reference = wasm_memory_reference() + (new_base - old_base);

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

This might read a bit clearer as:

new_base + (wasm_memory_reference() - old_base)

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

Done.

+  DCHECK(new_base <= updated_reference &&
+         updated_reference <= new_base + new_size);
+  Assembler::set_target_address_at(isolate_, pc_, host_, updated_reference,
+                                   icache_flush_mode);
+}
 
 Object* RelocInfo::target_object() {
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);