1 // Copyright 2011 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // CPU specific code for ia32 independent of OS goes here. 6 7 #ifdef __GNUC__ 8 #include "src/third_party/valgrind/valgrind.h" 9 #endif 10 11 #if V8_TARGET_ARCH_X87 12 13 #include "src/assembler.h" 14 #include "src/macro-assembler.h" 15 16 namespace v8 { 17 namespace internal { 18 19 void CpuFeatures::FlushICache(void* start, size_t size) { 20 // No need to flush the instruction cache on Intel. On Intel instruction 21 // cache flushing is only necessary when multiple cores running the same 22 // code simultaneously. V8 (and JavaScript) is single threaded and when code 23 // is patched on an intel CPU the core performing the patching will have its 24 // own instruction cache updated automatically. 25 26 // If flushing of the instruction cache becomes necessary Windows has the 27 // API function FlushInstructionCache. 28 29 // By default, valgrind only checks the stack for writes that might need to 30 // invalidate already cached translated code. This leads to random 31 // instability when code patches or moves are sometimes unnoticed. One 32 // solution is to run valgrind with --smc-check=all, but this comes at a big 33 // performance cost. We can notify valgrind to invalidate its cache. 34 #ifdef VALGRIND_DISCARD_TRANSLATIONS 35 unsigned res = VALGRIND_DISCARD_TRANSLATIONS(start, size); 36 USE(res); 37 #endif 38 } 39 40 } // namespace internal 41 } // namespace v8 42 43 #endif // V8_TARGET_ARCH_X87 44
