From 6feac8a39b6607c5be2a9284711b2a9da0feea8f Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Thu, 29 Apr 2010 19:32:19 +0000 Subject: [PATCH] Make naked functions work on PPC. llvm-svn: 102657 --- llvm/lib/CodeGen/PrologEpilogInserter.cpp | 4 ++++ llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp | 8 +++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp index 365a84ab5242..16bf6ea765f6 100644 --- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp +++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp @@ -197,6 +197,10 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { if (CSRegs == 0 || CSRegs[0] == 0) return; + // In Naked functions we aren't going to save any registers. + if (Fn.getFunction()->hasFnAttr(Attribute::Naked)) + return; + // Figure out which *callee saved* registers are modified by the current // function, thus needing to be saved and restored in the prolog/epilog. const TargetRegisterClass * const *CSRegClasses = diff --git a/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp b/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp index 8048df21b7d6..5f1e04eecb4a 100644 --- a/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp +++ b/llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp @@ -409,6 +409,9 @@ PPCRegisterInfo::getCalleeSavedRegClasses(const MachineFunction *MF) const { // static bool needsFP(const MachineFunction &MF) { const MachineFrameInfo *MFI = MF.getFrameInfo(); + // Naked functions have no stack frame pushed, so we don't have a frame pointer. + if (MF.getFunction()->hasFnAttr(Attribute::Naked)) + return false; return DisableFramePointerElim(MF) || MFI->hasVarSizedObjects() || (GuaranteedTailCallOpt && MF.getInfo()->hasFastCall()); } @@ -794,7 +797,10 @@ PPCRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, // If we're not using a Frame Pointer that has been set to the value of the // SP before having the stack size subtracted from it, then add the stack size // to Offset to get the correct offset. - Offset += MFI->getStackSize(); + // Naked functions have stack size 0, although getStackSize may not reflect that + // because we didn't call all the pieces that compute it for naked functions. + if (!MF.getFunction()->hasFnAttr(Attribute::Naked)) + Offset += MFI->getStackSize(); // If we can, encode the offset directly into the instruction. If this is a // normal PPC "ri" instruction, any 16-bit value can be safely encoded. If