Use the 'target-features' and 'target-cpu' attributes to reset the subtarget features.

If two functions require different features (e.g., `-mno-sse' vs. `-msse') then
we want to honor that, especially during LTO. We can do that by resetting the
subtarget's features depending upon the 'target-feature' attribute.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175314 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2013-02-15 22:31:27 +00:00
parent 4fb25b7d79
commit 789cb5df9c
4 changed files with 75 additions and 41 deletions

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@ -19,6 +19,7 @@
namespace llvm {
class MachineFunction;
class MachineInstr;
class SDep;
class SUnit;
@ -73,6 +74,9 @@ public:
// the latency of a schedule dependency.
virtual void adjustSchedDependency(SUnit *def, SUnit *use,
SDep& dep) const { }
/// \brief Reset the features for the subtarget.
virtual void resetSubtargetFeatures(const MachineFunction *MF) { }
};
} // End llvm namespace

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@ -354,6 +354,10 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
TTI = getAnalysisIfAvailable<TargetTransformInfo>();
GFI = Fn.hasGC() ? &getAnalysis<GCModuleInfo>().getFunctionInfo(Fn) : 0;
TargetSubtargetInfo &ST =
const_cast<TargetSubtargetInfo&>(TM.getSubtarget<TargetSubtargetInfo>());
ST.resetSubtargetFeatures(MF);
DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);

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@ -14,6 +14,8 @@
#define DEBUG_TYPE "subtarget"
#include "X86Subtarget.h"
#include "X86InstrInfo.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
@ -324,46 +326,21 @@ void X86Subtarget::AutoDetectSubtargetFeatures() {
}
}
X86Subtarget::X86Subtarget(const std::string &TT, const std::string &CPU,
const std::string &FS,
unsigned StackAlignOverride, bool is64Bit)
: X86GenSubtargetInfo(TT, CPU, FS)
, X86ProcFamily(Others)
, PICStyle(PICStyles::None)
, X86SSELevel(NoMMXSSE)
, X863DNowLevel(NoThreeDNow)
, HasCMov(false)
, HasX86_64(false)
, HasPOPCNT(false)
, HasSSE4A(false)
, HasAES(false)
, HasPCLMUL(false)
, HasFMA(false)
, HasFMA4(false)
, HasXOP(false)
, HasMOVBE(false)
, HasRDRAND(false)
, HasF16C(false)
, HasFSGSBase(false)
, HasLZCNT(false)
, HasBMI(false)
, HasBMI2(false)
, HasRTM(false)
, HasADX(false)
, IsBTMemSlow(false)
, IsUAMemFast(false)
, HasVectorUAMem(false)
, HasCmpxchg16b(false)
, UseLeaForSP(false)
, HasSlowDivide(false)
, PostRAScheduler(false)
, PadShortFunctions(false)
, stackAlignment(4)
// FIXME: this is a known good value for Yonah. How about others?
, MaxInlineSizeThreshold(128)
, TargetTriple(TT)
, In64BitMode(is64Bit) {
// Determine default and user specified characteristics
void X86Subtarget::resetSubtargetFeatures(const MachineFunction *MF) {
AttributeSet FnAttrs = MF->getFunction()->getAttributes();
Attribute CPUAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
"target-cpu");
Attribute FSAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
"target-features");
std::string CPU =
!CPUAttr.hasAttribute(Attribute::None) ?CPUAttr.getValueAsString() : "";
std::string FS =
!FSAttr.hasAttribute(Attribute::None) ? FSAttr.getValueAsString() : "";
if (!FS.empty())
resetSubtargetFeatures(CPU, FS);
}
void X86Subtarget::resetSubtargetFeatures(StringRef CPU, StringRef FS) {
std::string CPUName = CPU;
if (!FS.empty() || !CPU.empty()) {
if (CPUName.empty()) {
@ -440,6 +417,49 @@ X86Subtarget::X86Subtarget(const std::string &TT, const std::string &CPU,
stackAlignment = 16;
}
X86Subtarget::X86Subtarget(const std::string &TT, const std::string &CPU,
const std::string &FS,
unsigned StackAlignOverride, bool is64Bit)
: X86GenSubtargetInfo(TT, CPU, FS)
, X86ProcFamily(Others)
, PICStyle(PICStyles::None)
, X86SSELevel(NoMMXSSE)
, X863DNowLevel(NoThreeDNow)
, HasCMov(false)
, HasX86_64(false)
, HasPOPCNT(false)
, HasSSE4A(false)
, HasAES(false)
, HasPCLMUL(false)
, HasFMA(false)
, HasFMA4(false)
, HasXOP(false)
, HasMOVBE(false)
, HasRDRAND(false)
, HasF16C(false)
, HasFSGSBase(false)
, HasLZCNT(false)
, HasBMI(false)
, HasBMI2(false)
, HasRTM(false)
, HasADX(false)
, IsBTMemSlow(false)
, IsUAMemFast(false)
, HasVectorUAMem(false)
, HasCmpxchg16b(false)
, UseLeaForSP(false)
, HasSlowDivide(false)
, PostRAScheduler(false)
, PadShortFunctions(false)
, stackAlignment(4)
// FIXME: this is a known good value for Yonah. How about others?
, MaxInlineSizeThreshold(128)
, TargetTriple(TT)
, StackAlignOverride(StackAlignOverride)
, In64BitMode(is64Bit) {
resetSubtargetFeatures(CPU, FS);
}
bool X86Subtarget::enablePostRAScheduler(
CodeGenOpt::Level OptLevel,
TargetSubtargetInfo::AntiDepBreakMode& Mode,

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@ -168,11 +168,13 @@ protected:
InstrItineraryData InstrItins;
private:
/// StackAlignOverride - Override the stack alignment.
unsigned StackAlignOverride;
/// In64BitMode - True if compiling for 64-bit, false for 32-bit.
bool In64BitMode;
public:
/// This constructor initializes the data members to match that
/// of the specified triple.
///
@ -197,6 +199,10 @@ public:
/// instruction.
void AutoDetectSubtargetFeatures();
/// \brief Reset the features for the X86 target.
virtual void resetSubtargetFeatures(const MachineFunction *MF);
void resetSubtargetFeatures(StringRef CPU, StringRef FS);
/// Is this x86_64? (disregarding specific ABI / programming model)
bool is64Bit() const {
return In64BitMode;