Assembler changes for enabling GrowHeap in Wasm

src/arm/assembler-arm-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 53 matching lines @@
   // We do not use pc relative addressing on ARM, so there is
   // nothing else to do.
 }
 
 
 Address RelocInfo::target_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
   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_)
                               || rmode_ == EMBEDDED_OBJECT
                               || rmode_ == EXTERNAL_REFERENCE);
   if (FLAG_enable_embedded_constant_pool ||
       Assembler::IsMovW(Memory::int32_at(pc_))) {
     // We return the PC for embedded constant pool since this function is used
     // by the serializer and expects the address to reside within the code
     // object.
@@ skipping 23 matching lines @@
   Assembler::set_target_address_at(isolate_, pc_, host_, target,
                                    icache_flush_mode);
   if (write_barrier_mode == UPDATE_WRITE_BARRIER &&
       host() != NULL && IsCodeTarget(rmode_)) {
     Object* target_code = Code::GetCodeFromTargetAddress(target);
     host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
         host(), this, HeapObject::cast(target_code));
   }
 }
 
+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_base <= wasm_memory_reference() &&
+         wasm_memory_reference() <= old_base + old_size);

[Yang, 2016/03/15 07:44:18]

Should this really be a "less-equals" or just a "less"? I can't imagine the
reference pointing to outside the memory (which old_base + old_size would be).

Same for the compare below and on other platform ports.

[gdeepti1, 2016/03/16 06:05:26]

Fixed below and on other platform ports. 

+  Address updated_reference = new_base + (wasm_memory_reference() - old_base);
+  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);
   return reinterpret_cast<Object*>(Assembler::target_address_at(pc_, host_));
 }
 
 
 Handle<Object> RelocInfo::target_object_handle(Assembler* origin) {
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
   return Handle<Object>(reinterpret_cast<Object**>(
@@ skipping 476 matching lines @@
       Assembler::FlushICache(isolate, pc, 4 * kInstrSize);
     }
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM_ASSEMBLER_ARM_INL_H_