diff options
Diffstat (limited to 'src/google/protobuf/stubs/atomicops_internals_x86_gcc.cc')
| -rw-r--r-- | src/google/protobuf/stubs/atomicops_internals_x86_gcc.cc | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/src/google/protobuf/stubs/atomicops_internals_x86_gcc.cc b/src/google/protobuf/stubs/atomicops_internals_x86_gcc.cc deleted file mode 100644 index 53c9eae0..00000000 --- a/src/google/protobuf/stubs/atomicops_internals_x86_gcc.cc +++ /dev/null @@ -1,137 +0,0 @@ -// Protocol Buffers - Google's data interchange format -// Copyright 2012 Google Inc. All rights reserved. -// https://developers.google.com/protocol-buffers/ -// -// Redistribution and use in source and binary forms, with or without -// modification, are permitted provided that the following conditions are -// met: -// -// * Redistributions of source code must retain the above copyright -// notice, this list of conditions and the following disclaimer. -// * Redistributions in binary form must reproduce the above -// copyright notice, this list of conditions and the following disclaimer -// in the documentation and/or other materials provided with the -// distribution. -// * Neither the name of Google Inc. nor the names of its -// contributors may be used to endorse or promote products derived from -// this software without specific prior written permission. -// -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -// This module gets enough CPU information to optimize the -// atomicops module on x86. - -#include <cstring> - -#include <google/protobuf/stubs/atomicops.h> - -// This file only makes sense with atomicops_internals_x86_gcc.h -- it -// depends on structs that are defined in that file. If atomicops.h -// doesn't sub-include that file, then we aren't needed, and shouldn't -// try to do anything. -#ifdef GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_X86_GCC_H_ - -// Inline cpuid instruction. In PIC compilations, %ebx contains the address -// of the global offset table. To avoid breaking such executables, this code -// must preserve that register's value across cpuid instructions. -#if defined(__i386__) -#define cpuid(a, b, c, d, inp) \ - asm("mov %%ebx, %%edi\n" \ - "cpuid\n" \ - "xchg %%edi, %%ebx\n" \ - : "=a" (a), "=D" (b), "=c" (c), "=d" (d) : "a" (inp)) -#elif defined(__x86_64__) -#define cpuid(a, b, c, d, inp) \ - asm("mov %%rbx, %%rdi\n" \ - "cpuid\n" \ - "xchg %%rdi, %%rbx\n" \ - : "=a" (a), "=D" (b), "=c" (c), "=d" (d) : "a" (inp)) -#endif - -#if defined(cpuid) // initialize the struct only on x86 - -namespace google { -namespace protobuf { -namespace internal { - -// Set the flags so that code will run correctly and conservatively, so even -// if we haven't been initialized yet, we're probably single threaded, and our -// default values should hopefully be pretty safe. -struct AtomicOps_x86CPUFeatureStruct AtomicOps_Internalx86CPUFeatures = { - false, // bug can't exist before process spawns multiple threads - false, // no SSE2 -}; - -namespace { - -// Initialize the AtomicOps_Internalx86CPUFeatures struct. -void AtomicOps_Internalx86CPUFeaturesInit() { - uint32_t eax; - uint32_t ebx; - uint32_t ecx; - uint32_t edx; - - // Get vendor string (issue CPUID with eax = 0) - cpuid(eax, ebx, ecx, edx, 0); - char vendor[13]; - memcpy(vendor, &ebx, 4); - memcpy(vendor + 4, &edx, 4); - memcpy(vendor + 8, &ecx, 4); - vendor[12] = 0; - - // get feature flags in ecx/edx, and family/model in eax - cpuid(eax, ebx, ecx, edx, 1); - - int family = (eax >> 8) & 0xf; // family and model fields - int model = (eax >> 4) & 0xf; - if (family == 0xf) { // use extended family and model fields - family += (eax >> 20) & 0xff; - model += ((eax >> 16) & 0xf) << 4; - } - - // Opteron Rev E has a bug in which on very rare occasions a locked - // instruction doesn't act as a read-acquire barrier if followed by a - // non-locked read-modify-write instruction. Rev F has this bug in - // pre-release versions, but not in versions released to customers, - // so we test only for Rev E, which is family 15, model 32..63 inclusive. - if (strcmp(vendor, "AuthenticAMD") == 0 && // AMD - family == 15 && - 32 <= model && model <= 63) { - AtomicOps_Internalx86CPUFeatures.has_amd_lock_mb_bug = true; - } else { - AtomicOps_Internalx86CPUFeatures.has_amd_lock_mb_bug = false; - } - - // edx bit 26 is SSE2 which we use to tell use whether we can use mfence - AtomicOps_Internalx86CPUFeatures.has_sse2 = ((edx >> 26) & 1); -} - -class AtomicOpsx86Initializer { - public: - AtomicOpsx86Initializer() { - AtomicOps_Internalx86CPUFeaturesInit(); - } -}; - -// A global to get use initialized on startup via static initialization :/ -AtomicOpsx86Initializer g_initer; - -} // namespace - -} // namespace internal -} // namespace protobuf -} // namespace google - -#endif // __i386__ - -#endif // GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_X86_GCC_H_ |