Files
sdk/runtime/vm/debugger_ia32.cc
Vyacheslav Egorov d194fcecaf [vm] Use dual mapping of code pages on certain OS versions
Heap references always point into R/RW mapping (this simplifies the
marker) and entry points are retargeted into RX.

To simplify implementation we assume that there are no image pages
created - which means we can always go from Instructions to the start of
the page and check where it is dual mapped to.

TEST=vm/dart/macos_dual_mapping_smoke_test and manually on physical
device

Change-Id: Idbe02b7b695b3c048072cf92f7d062f5ab6e1beb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/433940
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2025-06-12 20:46:54 -07:00

85 lines
2.6 KiB
C++

// Copyright (c) 2011, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/globals.h"
#if defined(TARGET_ARCH_IA32)
#include "vm/debugger.h"
#include "vm/code_patcher.h"
#include "vm/compiler/assembler/disassembler.h"
#include "vm/cpu.h"
#include "vm/object.h"
#include "vm/os.h"
#include "vm/stack_frame.h"
#include "vm/stub_code.h"
namespace dart {
#ifndef PRODUCT
CodePtr CodeBreakpoint::OrigStubAddress() const {
return saved_value_;
}
void CodeBreakpoint::PatchCode() {
ASSERT(!IsEnabled());
auto thread = Thread::Current();
auto zone = thread->zone();
const Code& code = Code::Handle(zone, code_);
const Instructions& instrs = Instructions::Handle(zone, code.instructions());
Code& stub_target = Code::Handle(zone);
thread->isolate_group()->RunWithStoppedMutators([&]() {
WritableInstructionsScope writable(instrs.WritablePayloadStart(),
instrs.Size());
switch (breakpoint_kind_) {
case UntaggedPcDescriptors::kIcCall: {
stub_target = StubCode::ICCallBreakpoint().ptr();
break;
}
case UntaggedPcDescriptors::kUnoptStaticCall: {
stub_target = StubCode::UnoptStaticCallBreakpoint().ptr();
break;
}
case UntaggedPcDescriptors::kRuntimeCall: {
saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
stub_target = StubCode::RuntimeCallBreakpoint().ptr();
break;
}
default:
UNREACHABLE();
}
saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
CodePatcher::PatchStaticCallAt(pc_, code, stub_target);
});
}
void CodeBreakpoint::RestoreCode() {
ASSERT(IsEnabled());
auto thread = Thread::Current();
auto zone = thread->zone();
const Code& code = Code::Handle(zone, code_);
const Instructions& instrs = Instructions::Handle(zone, code.instructions());
thread->isolate_group()->RunWithStoppedMutators([&]() {
WritableInstructionsScope writable(instrs.WritablePayloadStart(),
instrs.Size());
switch (breakpoint_kind_) {
case UntaggedPcDescriptors::kIcCall:
case UntaggedPcDescriptors::kUnoptStaticCall:
case UntaggedPcDescriptors::kRuntimeCall: {
CodePatcher::PatchStaticCallAt(pc_, code, Code::Handle(saved_value_));
break;
}
default:
UNREACHABLE();
}
});
}
#endif // !PRODUCT
} // namespace dart
#endif // defined TARGET_ARCH_IA32