diff options
| -rw-r--r-- | lib/Target/X86/X86FloatingPoint.cpp | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/lib/Target/X86/X86FloatingPoint.cpp b/lib/Target/X86/X86FloatingPoint.cpp index 30763f0b98..899f7cd6fe 100644 --- a/lib/Target/X86/X86FloatingPoint.cpp +++ b/lib/Target/X86/X86FloatingPoint.cpp @@ -157,6 +157,21 @@ FunctionPass *llvm::createX86FloatingPointStackifierPass() { return new FPS(); } /// register references into FP stack references. /// bool FPS::runOnMachineFunction(MachineFunction &MF) { + // We only need to run this pass if there are any FP registers used in this + // function. If it is all integer, there is nothing for us to do! + const bool *PhysRegsUsed = MF.getUsedPhysregs(); + bool FPIsUsed = false; + + assert(X86::FP6 == X86::FP0+6 && "Register enums aren't sorted right!"); + for (unsigned i = 0; i <= 6; ++i) + if (PhysRegsUsed[X86::FP0+i]) { + FPIsUsed = true; + break; + } + + // Early exit. + if (!FPIsUsed) return false; + LV = &getAnalysis<LiveVariables>(); StackTop = 0; |