1a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// Copyright 2010 the V8 project authors. All rights reserved. 2a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// Redistribution and use in source and binary forms, with or without 3a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// modification, are permitted provided that the following conditions are 4a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// met: 5a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// 6a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// * Redistributions of source code must retain the above copyright 7a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// notice, this list of conditions and the following disclaimer. 8a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// * Redistributions in binary form must reproduce the above 9a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// copyright notice, this list of conditions and the following 10a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// disclaimer in the documentation and/or other materials provided 11a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// with the distribution. 12a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// * Neither the name of Google Inc. nor the names of its 13a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// contributors may be used to endorse or promote products derived 14a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// from this software without specific prior written permission. 15a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// 16a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 28a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// This module gets enough CPU information to optimize the 29a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// atomicops module on x86. 30a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 31a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#include <string.h> 32a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 33a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#include "atomicops.h" 34e27d617298263725e8a48c2aa14029759b952623mstarzinger@chromium.org#include "platform.h" 35a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 36a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// This file only makes sense with atomicops_internals_x86_gcc.h -- it 37a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// depends on structs that are defined in that file. If atomicops.h 38a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// doesn't sub-include that file, then we aren't needed, and shouldn't 39a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// try to do anything. 40a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#ifdef V8_ATOMICOPS_INTERNALS_X86_GCC_H_ 41a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 42a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// Inline cpuid instruction. In PIC compilations, %ebx contains the address 43a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// of the global offset table. To avoid breaking such executables, this code 44a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// must preserve that register's value across cpuid instructions. 45a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#if defined(__i386__) 46a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#define cpuid(a, b, c, d, inp) \ 47a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org asm("mov %%ebx, %%edi\n" \ 48a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org "cpuid\n" \ 49a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org "xchg %%edi, %%ebx\n" \ 50a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org : "=a" (a), "=D" (b), "=c" (c), "=d" (d) : "a" (inp)) 51a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#elif defined(__x86_64__) 52a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#define cpuid(a, b, c, d, inp) \ 53a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org asm("mov %%rbx, %%rdi\n" \ 54a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org "cpuid\n" \ 55a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org "xchg %%rdi, %%rbx\n" \ 56a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org : "=a" (a), "=D" (b), "=c" (c), "=d" (d) : "a" (inp)) 57a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#endif 58a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 59a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#if defined(cpuid) // initialize the struct only on x86 60a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 618e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.orgnamespace v8 { 628e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.orgnamespace internal { 638e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org 64a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// Set the flags so that code will run correctly and conservatively, so even 65a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// if we haven't been initialized yet, we're probably single threaded, and our 66a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// default values should hopefully be pretty safe. 67a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.orgstruct AtomicOps_x86CPUFeatureStruct AtomicOps_Internalx86CPUFeatures = { 68a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org false, // bug can't exist before process spawns multiple threads 69a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org false, // no SSE2 70a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org}; 71a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 728e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org} } // namespace v8::internal 738e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org 748e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.orgnamespace { 758e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org 76a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// Initialize the AtomicOps_Internalx86CPUFeatures struct. 778e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.orgvoid AtomicOps_Internalx86CPUFeaturesInit() { 788e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org using v8::internal::AtomicOps_Internalx86CPUFeatures; 798e8294a88dc7d58f579aee0ba08c19fc8a616e2dsgjesse@chromium.org 80a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org uint32_t eax; 81a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org uint32_t ebx; 82a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org uint32_t ecx; 83a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org uint32_t edx; 84a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 85a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // Get vendor string (issue CPUID with eax = 0) 86a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org cpuid(eax, ebx, ecx, edx, 0); 87a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org char vendor[13]; 88e27d617298263725e8a48c2aa14029759b952623mstarzinger@chromium.org v8::internal::OS::MemCopy(vendor, &ebx, 4); 89e27d617298263725e8a48c2aa14029759b952623mstarzinger@chromium.org v8::internal::OS::MemCopy(vendor + 4, &edx, 4); 90e27d617298263725e8a48c2aa14029759b952623mstarzinger@chromium.org v8::internal::OS::MemCopy(vendor + 8, &ecx, 4); 91a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org vendor[12] = 0; 92a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 93a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // get feature flags in ecx/edx, and family/model in eax 94a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org cpuid(eax, ebx, ecx, edx, 1); 95a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 96a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org int family = (eax >> 8) & 0xf; // family and model fields 97a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org int model = (eax >> 4) & 0xf; 98a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org if (family == 0xf) { // use extended family and model fields 99a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org family += (eax >> 20) & 0xff; 100a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org model += ((eax >> 16) & 0xf) << 4; 101a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org } 102a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 103a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // Opteron Rev E has a bug in which on very rare occasions a locked 104a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // instruction doesn't act as a read-acquire barrier if followed by a 105a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // non-locked read-modify-write instruction. Rev F has this bug in 106a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // pre-release versions, but not in versions released to customers, 107a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // so we test only for Rev E, which is family 15, model 32..63 inclusive. 108a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org if (strcmp(vendor, "AuthenticAMD") == 0 && // AMD 109a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org family == 15 && 110a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 32 <= model && model <= 63) { 111a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org AtomicOps_Internalx86CPUFeatures.has_amd_lock_mb_bug = true; 112a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org } else { 113a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org AtomicOps_Internalx86CPUFeatures.has_amd_lock_mb_bug = false; 114a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org } 115a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 116a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org // edx bit 26 is SSE2 which we use to tell use whether we can use mfence 117a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org AtomicOps_Internalx86CPUFeatures.has_sse2 = ((edx >> 26) & 1); 118a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org} 119a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 120a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.orgclass AtomicOpsx86Initializer { 121a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org public: 122a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org AtomicOpsx86Initializer() { 123a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org AtomicOps_Internalx86CPUFeaturesInit(); 124a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org } 125a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org}; 126a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 127e0e1b0d3e70c933d36ed381d511e9fda39f2a751mstarzinger@chromium.org 128a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org// A global to get use initialized on startup via static initialization :/ 129a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.orgAtomicOpsx86Initializer g_initer; 130a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 131a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org} // namespace 132a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 133a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#endif // if x86 134a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org 135a55512615f5adc085d23bc8589d155c4b579fb7bkasperl@chromium.org#endif // ifdef V8_ATOMICOPS_INTERNALS_X86_GCC_H_ 136