std::string TargetFS;
/// CodeGenInfo - Low level target information such as relocation model.
- const MCCodeGenInfo *CodeGenInfo;
+ /// Non-const to allow resetting optimization level per-function.
+ MCCodeGenInfo *CodeGenInfo;
/// AsmInfo - Contains target specific asm information.
///
/// Default, or Aggressive.
CodeGenOpt::Level getOptLevel() const;
+ /// \brief Overrides the optimization level.
+ void setOptLevel(CodeGenOpt::Level Level) const;
+
void setFastISel(bool Enable) { Options.EnableFastISel = Enable; }
bool shouldPrintMachineCode() const { return Options.PrintMachineCode; }
namespace llvm {
//===--------------------------------------------------------------------===//
+ /// \brief This struct is used by SelectionDAGISel to temporarily override
+ /// the optimization level on a per-function basis.
+ class OptLevelChanger {
+ SelectionDAGISel &IS;
+ CodeGenOpt::Level SavedOptLevel;
+
+ public:
+ OptLevelChanger(SelectionDAGISel &ISel,
+ CodeGenOpt::Level NewOptLevel) : IS(ISel) {
+ SavedOptLevel = IS.OptLevel;
+ if (NewOptLevel == SavedOptLevel)
+ return;
+ IS.OptLevel = NewOptLevel;
+ IS.TM.setOptLevel(NewOptLevel);
+ DEBUG(dbgs() << "\nChanging optimization level for Function "
+ << IS.MF->getFunction()->getName() << "\n");
+ DEBUG(dbgs() << "\tBefore: -O" << SavedOptLevel
+ << " ; After: -O" << NewOptLevel << "\n");
+ }
+
+ ~OptLevelChanger() {
+ if (IS.OptLevel == SavedOptLevel)
+ return;
+ DEBUG(dbgs() << "\nRestoring optimization level for Function "
+ << IS.MF->getFunction()->getName() << "\n");
+ DEBUG(dbgs() << "\tBefore: -O" << IS.OptLevel
+ << " ; After: -O" << SavedOptLevel << "\n");
+ IS.OptLevel = SavedOptLevel;
+ IS.TM.setOptLevel(SavedOptLevel);
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
/// createDefaultScheduler - This creates an instruction scheduler appropriate
/// for the target.
ScheduleDAGSDNodes* createDefaultScheduler(SelectionDAGISel *IS,
ST.resetSubtargetFeatures(MF);
TM.resetTargetOptions(MF);
+ // Reset OptLevel to None for optnone functions.
+ CodeGenOpt::Level NewOptLevel = OptLevel;
+ if (Fn.hasFnAttribute(Attribute::OptimizeNone))
+ NewOptLevel = CodeGenOpt::None;
+ OptLevelChanger OLC(*this, NewOptLevel);
+
DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);
void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
// Initialize the Fast-ISel state, if needed.
FastISel *FastIS = 0;
- if (TM.Options.EnableFastISel)
+ if (TM.Options.EnableFastISel || Fn.hasFnAttribute(Attribute::OptimizeNone))
FastIS = getTargetLowering()->createFastISel(*FuncInfo, LibInfo);
// Iterate over all basic blocks in the function.
--- /dev/null
+; RUN: llc -debug < %s -o /dev/null 2>&1 | FileCheck %s
+
+; Verify that the backend correctly overrides the optimization level
+; of optnone functions during instruction selection.
+
+define float @foo(float %x) #0 {
+entry:
+ %add = fadd fast float %x, %x
+ %add1 = fadd fast float %add, %x
+ ret float %add1
+}
+
+; CHECK-NOT: Changing optimization level for Function foo
+; CHECK-NOT: Restoring optimization level for Function foo
+
+; Function Attrs: noinline optnone
+define float @fooWithOptnone(float %x) #1 {
+entry:
+ %add = fadd fast float %x, %x
+ %add1 = fadd fast float %add, %x
+ ret float %add1
+}
+
+; CHECK: Changing optimization level for Function fooWithOptnone
+; CHECK-NEXT: Before: -O2 ; After: -O0
+
+; CHECK: Restoring optimization level for Function fooWithOptnone
+; CHECK-NEXT: Before: -O0 ; After: -O2
+
+attributes #0 = { "unsafe-fp-math"="true" }
+attributes #1 = { noinline optnone "unsafe-fp-math"="true" }