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authorEli Bendersky <eliben@chromium.org>2013-07-15 16:09:15 -0700
committerEli Bendersky <eliben@chromium.org>2013-07-15 16:09:15 -0700
commitc6cf05cb5108f356dde97c01ee4188b0671d4542 (patch)
tree436fdc2a55296d3c202e7ef11f31be3be53efb5f /lib/Support/Host.cpp
parentc75199c649c739aade160289d93f257edc798cde (diff)
parent7dfcb84fc16b3bf6b2379713b53090757f0a45f9 (diff)
Merge commit '7dfcb84fc16b3bf6b2379713b53090757f0a45f9'
Conflicts: docs/LangRef.rst include/llvm/CodeGen/CallingConvLower.h include/llvm/IRReader/IRReader.h include/llvm/Target/TargetMachine.h lib/CodeGen/CallingConvLower.cpp lib/IRReader/IRReader.cpp lib/IRReader/LLVMBuild.txt lib/IRReader/Makefile lib/LLVMBuild.txt lib/Makefile lib/Support/MemoryBuffer.cpp lib/Support/Unix/PathV2.inc lib/Target/ARM/ARMBaseInstrInfo.cpp lib/Target/ARM/ARMISelLowering.cpp lib/Target/ARM/ARMInstrInfo.td lib/Target/ARM/ARMSubtarget.cpp lib/Target/ARM/ARMTargetMachine.cpp lib/Target/Mips/CMakeLists.txt lib/Target/Mips/MipsDelaySlotFiller.cpp lib/Target/Mips/MipsISelLowering.cpp lib/Target/Mips/MipsInstrInfo.td lib/Target/Mips/MipsSubtarget.cpp lib/Target/Mips/MipsSubtarget.h lib/Target/X86/X86FastISel.cpp lib/Target/X86/X86ISelDAGToDAG.cpp lib/Target/X86/X86ISelLowering.cpp lib/Target/X86/X86InstrControl.td lib/Target/X86/X86InstrFormats.td lib/Transforms/IPO/ExtractGV.cpp lib/Transforms/InstCombine/InstCombineCompares.cpp lib/Transforms/Utils/SimplifyLibCalls.cpp test/CodeGen/X86/fast-isel-divrem.ll test/MC/ARM/data-in-code.ll tools/Makefile tools/llvm-extract/llvm-extract.cpp tools/llvm-link/CMakeLists.txt tools/opt/CMakeLists.txt tools/opt/LLVMBuild.txt tools/opt/Makefile tools/opt/opt.cpp
Diffstat (limited to 'lib/Support/Host.cpp')
-rw-r--r--lib/Support/Host.cpp41
1 files changed, 35 insertions, 6 deletions
diff --git a/lib/Support/Host.cpp b/lib/Support/Host.cpp
index b9bbcb9322..a7c7a95800 100644
--- a/lib/Support/Host.cpp
+++ b/lib/Support/Host.cpp
@@ -112,6 +112,21 @@ static bool GetX86CpuIDAndInfo(unsigned value, unsigned *rEAX,
#endif
}
+static bool OSHasAVXSupport() {
+#if defined(__GNUC__)
+ // Check xgetbv; this uses a .byte sequence instead of the instruction
+ // directly because older assemblers do not include support for xgetbv and
+ // there is no easy way to conditionally compile based on the assembler used.
+ int rEAX, rEDX;
+ __asm__ (".byte 0x0f, 0x01, 0xd0" : "=a" (rEAX), "=d" (rEDX) : "c" (0));
+#elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
+ unsigned long long rEAX = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
+#else
+ int rEAX = 0; // Ensures we return false
+#endif
+ return (rEAX & 6) == 6;
+}
+
static void DetectX86FamilyModel(unsigned EAX, unsigned &Family,
unsigned &Model) {
Family = (EAX >> 8) & 0xf; // Bits 8 - 11
@@ -134,6 +149,11 @@ std::string sys::getHostCPUName() {
DetectX86FamilyModel(EAX, Family, Model);
bool HasSSE3 = (ECX & 0x1);
+ // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
+ // indicates that the AVX registers will be saved and restored on context
+ // switch, then we have full AVX support.
+ const unsigned AVXBits = (1 << 27) | (1 << 28);
+ bool HasAVX = ((ECX & AVXBits) == AVXBits) && OSHasAVXSupport();
GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
bool Em64T = (EDX >> 29) & 0x1;
@@ -243,11 +263,15 @@ std::string sys::getHostCPUName() {
case 42: // Intel Core i7 processor. All processors are manufactured
// using the 32 nm process.
case 45:
- return "corei7-avx";
+ // Not all Sandy Bridge processors support AVX (such as the Pentium
+ // versions instead of the i7 versions).
+ return HasAVX ? "corei7-avx" : "corei7";
// Ivy Bridge:
case 58:
- return "core-avx-i";
+ // Not all Ivy Bridge processors support AVX (such as the Pentium
+ // versions instead of the i7 versions).
+ return HasAVX ? "core-avx-i" : "corei7";
case 28: // Most 45 nm Intel Atom processors
case 38: // 45 nm Atom Lincroft
@@ -331,10 +355,15 @@ std::string sys::getHostCPUName() {
case 20:
return "btver1";
case 21:
- if (Model <= 15)
- return "bdver1";
- else if (Model <= 31)
+ if (!HasAVX) // If the OS doesn't support AVX provide a sane fallback.
+ return "btver1";
+ if (Model > 15 && Model <= 31)
return "bdver2";
+ return "bdver1";
+ case 22:
+ if (!HasAVX) // If the OS doesn't support AVX provide a sane fallback.
+ return "btver1";
+ return "btver2";
default:
return "generic";
}
@@ -584,7 +613,7 @@ bool sys::getHostCPUFeatures(StringMap<bool> &Features){
#endif
std::string sys::getProcessTriple() {
- Triple PT(LLVM_HOSTTRIPLE);
+ Triple PT(LLVM_HOST_TRIPLE);
if (sizeof(void *) == 8 && PT.isArch32Bit())
PT = PT.get64BitArchVariant();