mirror of
https://github.com/dart-lang/sdk
synced 2024-09-05 00:13:50 +00:00
![Régis Crelier](/assets/img/avatar_default.png)
This is a reland of6da340bf76
Original change's description: > Reland "[VM runtime] Dual mapping of executable pages." > > This is a reland of44186dfdcd
> > Original change's description: > > [VM runtime] Dual mapping of executable pages. > > > > Change-Id: Iaad78d324e25462ce951f4df26974a6a368c50b7 > > Reviewed-on: https://dart-review.googlesource.com/c/93377 > > Commit-Queue: Régis Crelier <regis@google.com> > > Reviewed-by: Ryan Macnak <rmacnak@google.com> > > Change-Id: I7a0caa078950637d9fe831732577fd2467061099 > Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/95263 > Reviewed-by: Ryan Macnak <rmacnak@google.com> Change-Id: I3a01f0e67d733c5db41618f691431e72c1e1cb2e Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/96422 Reviewed-by: Ryan Macnak <rmacnak@google.com> Commit-Queue: Régis Crelier <regis@google.com>
59 lines
2 KiB
C++
59 lines
2 KiB
C++
// Copyright (c) 2012, 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/code_patcher.h"
|
|
#include "vm/cpu.h"
|
|
#include "vm/instructions.h"
|
|
#include "vm/object.h"
|
|
#include "vm/virtual_memory.h"
|
|
|
|
namespace dart {
|
|
|
|
DEFINE_FLAG(bool, write_protect_code, true, "Write protect jitted code");
|
|
|
|
#if defined(DUAL_MAPPING_SUPPORTED)
|
|
DEFINE_FLAG(bool, dual_map_code, true, "Dual map jitted code, RW and RX");
|
|
#else
|
|
DEFINE_FLAG(bool, dual_map_code, false, "Dual map jitted code, RW and RX");
|
|
#endif // defined(DUAL_MAPPING_SUPPORTED)
|
|
|
|
#if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_DBC)
|
|
WritableInstructionsScope::WritableInstructionsScope(uword address,
|
|
intptr_t size)
|
|
: address_(address), size_(size) {
|
|
if (FLAG_write_protect_code) {
|
|
VirtualMemory::Protect(reinterpret_cast<void*>(address), size,
|
|
VirtualMemory::kReadWrite);
|
|
}
|
|
}
|
|
|
|
WritableInstructionsScope::~WritableInstructionsScope() {
|
|
if (FLAG_write_protect_code) {
|
|
VirtualMemory::Protect(reinterpret_cast<void*>(address_), size_,
|
|
VirtualMemory::kReadExecute);
|
|
}
|
|
}
|
|
#endif // defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_DBC)
|
|
|
|
bool MatchesPattern(uword end, const int16_t* pattern, intptr_t size) {
|
|
// When breaking within generated code in GDB, it may overwrite individual
|
|
// instructions with trap instructions, which can cause this test to fail.
|
|
//
|
|
// Ignoring trap instructions would work well enough within GDB alone, but it
|
|
// doesn't work in RR, because the check for the trap instrution itself will
|
|
// cause replay to diverge from the original record.
|
|
if (FLAG_support_rr) return true;
|
|
|
|
uint8_t* bytes = reinterpret_cast<uint8_t*>(end - size);
|
|
for (intptr_t i = 0; i < size; i++) {
|
|
int16_t val = pattern[i];
|
|
if ((val >= 0) && (val != bytes[i])) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
} // namespace dart
|