1 // Copyright 2009 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
4 // met:
5 //
6 // * Redistributions of source code must retain the above copyright
7 // notice, this list of conditions and the following disclaimer.
8 // * Redistributions in binary form must reproduce the above
9 // copyright notice, this list of conditions and the following
10 // disclaimer in the documentation and/or other materials provided
11 // with the distribution.
12 // * Neither the name of Google Inc. nor the names of its
13 // contributors may be used to endorse or promote products derived
14 // from this software without specific prior written permission.
15 //
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28 // CPU specific code for x64 independent of OS goes here.
29
30 #ifdef __GNUC__
31 #include "third_party/valgrind/valgrind.h"
32 #endif
33
34 #include "v8.h"
35
36 #include "cpu.h"
37 #include "macro-assembler.h"
38
39 namespace v8 {
40 namespace internal {
41
Setup()42 void CPU::Setup() {
43 CpuFeatures::Probe();
44 }
45
46
FlushICache(void * start,size_t size)47 void CPU::FlushICache(void* start, size_t size) {
48 // No need to flush the instruction cache on Intel. On Intel instruction
49 // cache flushing is only necessary when multiple cores running the same
50 // code simultaneously. V8 (and JavaScript) is single threaded and when code
51 // is patched on an intel CPU the core performing the patching will have its
52 // own instruction cache updated automatically.
53
54 // If flushing of the instruction cache becomes necessary Windows has the
55 // API function FlushInstructionCache.
56
57 // By default, valgrind only checks the stack for writes that might need to
58 // invalidate already cached translated code. This leads to random
59 // instability when code patches or moves are sometimes unnoticed. One
60 // solution is to run valgrind with --smc-check=all, but this comes at a big
61 // performance cost. We can notify valgrind to invalidate its cache.
62 #ifdef VALGRIND_DISCARD_TRANSLATIONS
63 VALGRIND_DISCARD_TRANSLATIONS(start, size);
64 #endif
65 }
66
67
DebugBreak()68 void CPU::DebugBreak() {
69 #ifdef _MSC_VER
70 // To avoid Visual Studio runtime support the following code can be used
71 // instead
72 // __asm { int 3 }
73 __debugbreak();
74 #else
75 asm("int $3");
76 #endif
77 }
78
79 } } // namespace v8::internal
80