Add new relocation type WASM_MEMORY_SIZE_REFERENCE, use relocatable pointers to update wasm memory …

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 58 matching lines @@
 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_);
 }
 
+uint32_t RelocInfo::wasm_memory_size_reference() {
+  DCHECK(IsWasmMemorySizeReference(rmode_));
+  return reinterpret_cast<uint32_t>(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.
     return reinterpret_cast<Address>(pc_);
@@ skipping 22 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(

[titzer, 2016/05/04 11:21:22]

Can we move this into the .cc file? There are other big methods here, but I
think this isn't performance critical enough to warrant being in the -inl.h
file.

Here and in the other architectures as well.

[gdeepti, 2016/05/04 20:14:52]

Done.

-    Address old_base, Address new_base, size_t old_size, size_t new_size,
+    Address old_base, Address new_base, uint32_t old_size, uint32_t new_size,
     ICacheFlushMode icache_flush_mode) {
-  DCHECK(IsWasmMemoryReference(rmode_));
-  DCHECK(old_base <= wasm_memory_reference() &&
-         wasm_memory_reference() < old_base + old_size);
-  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);
+  DCHECK(IsWasmMemoryReference(rmode_) || IsWasmMemorySizeReference(rmode_));
+  if (IsWasmMemoryReference(rmode_)) {
+    Address updated_memory_reference;
+    DCHECK(old_base <= wasm_memory_reference() &&
+           wasm_memory_reference() < old_base + old_size);
+    updated_memory_reference = new_base + (wasm_memory_reference() - old_base);
+    DCHECK(new_base <= updated_memory_reference &&
+           updated_memory_reference < new_base + new_size);
+    Assembler::set_target_address_at(
+        isolate_, pc_, host_, updated_memory_reference, icache_flush_mode);
+  } else if (IsWasmMemorySizeReference(rmode_)) {
+    uint32_t updated_size_reference;
+    DCHECK(wasm_memory_size_reference() <= old_size);
+    updated_size_reference =
+        new_size + (wasm_memory_size_reference() - old_size);
+    DCHECK(updated_size_reference <= new_size);
+    Assembler::set_target_address_at(
+        isolate_, pc_, host_, reinterpret_cast<Address>(updated_size_reference),
+        icache_flush_mode);
+  } else {
+    UNREACHABLE();
+  }
 }
 
 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);
@@ skipping 477 matching lines @@
       Assembler::FlushICache(isolate, pc, 4 * kInstrSize);
     }
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM_ASSEMBLER_ARM_INL_H_