X87: Assembler changes for enabling GrowHeap in Wasm

  port e1a7c1e7 (r34836)

  original commit message:
   - New RelocInfo mode WASM_MEMORY_REFERENCE as a marker for wasm code objects that need to be relocated on a heap change
   - RelocInfo mode recorded for immediates that use the memory buffer as base
   - Tests to verify address patching works

BUG=

Review URL: https://codereview.chromium.org/1809973002

Cr-Commit-Position: refs/heads/master@{#34845}

src/x87/assembler-x87-inl.h

@@ -81,6 +81,10 @@ Address RelocInfo::target_address() {
   return Assembler::target_address_at(pc_, host_);
 }
 
+Address RelocInfo::wasm_memory_reference() {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  return Memory::Address_at(pc_);
+}
 
 Address RelocInfo::target_address_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
@@ -116,6 +120,20 @@ 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_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);
+  Memory::Address_at(pc_) = updated_reference;
+  if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
+    Assembler::FlushICache(isolate_, pc_, sizeof(int32_t));
+  }
+}
 
 Object* RelocInfo::target_object() {
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
@@ -322,6 +340,10 @@ Immediate::Immediate(int x)  {
   rmode_ = RelocInfo::NONE32;
 }
 
+Immediate::Immediate(Address x, RelocInfo::Mode rmode) {
+  x_ = reinterpret_cast<int32_t>(x);
+  rmode_ = rmode;
+}
 
 Immediate::Immediate(const ExternalReference& ext) {
   x_ = reinterpret_cast<int32_t>(ext.address());

src/x87/assembler-x87.h

@@ -272,6 +272,7 @@ class Immediate BASE_EMBEDDED {
   inline explicit Immediate(Handle<Object> handle);
   inline explicit Immediate(Smi* value);
   inline explicit Immediate(Address addr);
+  inline explicit Immediate(Address x, RelocInfo::Mode rmode);
 
   static Immediate CodeRelativeOffset(Label* label) {
     return Immediate(label);

test/cctest/cctest.gyp

@@ -293,7 +293,8 @@
             'test-code-stubs-x87.cc',
             'test-disasm-x87.cc',
             'test-macro-assembler-x87.cc',
-            'test-log-stack-tracer.cc'
+            'test-log-stack-tracer.cc',
+            'test-run-wasm-relocation-x87.cc'
           ],
         }],
         [ 'OS=="linux" or OS=="qnx"', {

test/cctest/test-run-wasm-relocation-x87.cc

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <stdlib.h>
+
+#include "src/v8.h"
+
+#include "src/debug/debug.h"
+#include "src/disasm.h"
+#include "src/disassembler.h"
+#include "src/ic/ic.h"
+#include "src/macro-assembler.h"
+#include "src/x87/frames-x87.h"
+#include "test/cctest/cctest.h"
+#include "test/cctest/compiler/c-signature.h"
+#include "test/cctest/compiler/call-tester.h"
+
+using namespace v8::internal;
+using namespace v8::internal::compiler;
+
+#define __ assm.
+
+static int32_t DummyStaticFunction(Object* result) { return 1; }
+
+TEST(WasmRelocationIa32) {
+  CcTest::InitializeVM();
+  Zone zone;
+  Isolate* isolate = CcTest::i_isolate();
+  HandleScope scope(isolate);
+  v8::internal::byte buffer[4096];
+  Assembler assm(isolate, buffer, sizeof buffer);
+  DummyStaticFunction(NULL);
+  int32_t imm = 1234567;
+
+  __ mov(eax, Immediate(reinterpret_cast<Address>(imm),
+                        RelocInfo::WASM_MEMORY_REFERENCE));
+  __ nop();
+  __ ret(0);
+
+  CSignature0<int32_t> csig;
+  CodeDesc desc;
+  assm.GetCode(&desc);
+  Handle<Code> code = isolate->factory()->NewCode(
+      desc, Code::ComputeFlags(Code::STUB), Handle<Code>());
+  USE(code);
+
+  CodeRunner<int32_t> runnable(isolate, code, &csig);
+  int32_t ret_value = runnable.Call();
+  CHECK_EQ(ret_value, imm);
+
+#ifdef OBJECT_PRINT
+  OFStream os(stdout);
+  code->Print(os);
+  byte* begin = code->instruction_start();
+  byte* end = begin + code->instruction_size();
+  disasm::Disassembler::Disassemble(stdout, begin, end);
+#endif
+
+  size_t offset = 1234;
+
+  // Relocating references by offset
+  int mode_mask = (1 << RelocInfo::WASM_MEMORY_REFERENCE);
+  for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
+    RelocInfo::Mode mode = it.rinfo()->rmode();
+    if (RelocInfo::IsWasmMemoryReference(mode)) {
+      // Dummy values of size used here as the objective of the test is to
+      // verify that the immediate is patched correctly
+      it.rinfo()->update_wasm_memory_reference(
+          it.rinfo()->wasm_memory_reference(),
+          it.rinfo()->wasm_memory_reference() + offset, 1, 2,
+          SKIP_ICACHE_FLUSH);
+    }
+  }
+
+  // Check if immediate is updated correctly
+  ret_value = runnable.Call();
+  CHECK_EQ(ret_value, imm + offset);
+
+#ifdef OBJECT_PRINT
+  // OFStream os(stdout);
+  code->Print(os);
+  begin = code->instruction_start();
+  end = begin + code->instruction_size();
+  disasm::Disassembler::Disassemble(stdout, begin, end);
+#endif
+}
+
+#undef __