1 // Copyright 2014 The Chromium 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 #include "base/cpu.h" 6 #include "base/logging.h" 7 #include "base/strings/string_util.h" 8 #if defined(OS_WIN) 9 #include "base/win/windows_version.h" 10 #endif 11 12 namespace nacl { 13 14 const char* GetSandboxArch() { 15 #if defined(ARCH_CPU_ARM_FAMILY) 16 return "arm"; 17 #elif defined(ARCH_CPU_MIPS_FAMILY) 18 return "mips32"; 19 #elif defined(ARCH_CPU_X86_FAMILY) 20 21 #if defined(OS_WIN) 22 // We have to check the host architecture on Windows. 23 // See sandbox_isa.h for an explanation why. 24 if (base::win::OSInfo::GetInstance()->architecture() == 25 base::win::OSInfo::X64_ARCHITECTURE) 26 return "x86-64"; 27 else 28 return "x86-32"; 29 #elif ARCH_CPU_64_BITS 30 return "x86-64"; 31 #else 32 return "x86-32"; 33 #endif // defined(OS_WIN) 34 35 #else 36 #error Architecture not supported. 37 #endif 38 } 39 40 std::string GetCpuFeatures() { 41 // PNaCl's translator from pexe to nexe can be told exactly what 42 // capabilities the user's machine has because the pexe to nexe 43 // translation is specific to the machine, and CPU information goes 44 // into the translation cache. This allows the translator to generate 45 // faster code. 46 // 47 // Care must be taken to avoid instructions which aren't supported by 48 // the NaCl sandbox. Ideally the translator would do this, but there's 49 // no point in not doing the whitelist here. 50 // 51 // TODO(jfb) Some features are missing, either because the NaCl 52 // sandbox doesn't support them, because base::CPU doesn't 53 // detect them, or because they don't help vector shuffles 54 // (and we omit them because it simplifies testing). Add the 55 // other features. 56 // 57 // TODO(jfb) The following is x86-specific. The base::CPU class 58 // doesn't handle other architectures very well, and we 59 // should at least detect the presence of ARM's integer 60 // divide. 61 std::vector<std::string> features; 62 base::CPU cpu; 63 64 // On x86, SSE features are ordered: the most recent one implies the 65 // others. Care is taken here to only specify the latest SSE version, 66 // whereas non-SSE features don't follow this model: POPCNT is 67 // effectively always implied by SSE4.2 but has to be specified 68 // separately. 69 // 70 // TODO: AVX2, AVX, SSE 4.2. 71 if (cpu.has_sse41()) features.push_back("+sse4.1"); 72 // TODO: SSE 4A, SSE 4. 73 else if (cpu.has_ssse3()) features.push_back("+ssse3"); 74 // TODO: SSE 3 75 else if (cpu.has_sse2()) features.push_back("+sse2"); 76 77 // TODO: AES, POPCNT, LZCNT, ... 78 return JoinString(features, ','); 79 } 80 81 } // namespace nacl 82
