diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h index 65b60f7a936..212cc93401a 100644 --- a/include/llvm/Target/TargetRegisterInfo.h +++ b/include/llvm/Target/TargetRegisterInfo.h @@ -587,6 +587,17 @@ public: return !hasFP(MF); } + /// canSimplifyCallFramePseudos - When possible, it's best to simplify the + /// call frame pseudo ops before doing frame index elimination. This is + /// possible only when frame index references between the pseudos won't + /// need adjusted for the call frame adjustments. Normally, that's true + /// if the function has a reserved call frame or a frame pointer. Some + /// targets (Thumb2, for example) may have more complicated criteria, + /// however, and can override this behavior. + virtual bool canSimplifyCallFramePseudos(MachineFunction &MF) const { + return hasReservedCallFrame(MF) || hasFP(MF); + } + /// hasReservedSpillSlot - Return true if target has reserved a spill slot in /// the stack frame of the given function for the specified register. e.g. On /// x86, if the frame register is required, the first fixed stack object is diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp index 040259e15c5..138e7110306 100644 --- a/lib/CodeGen/PrologEpilogInserter.cpp +++ b/lib/CodeGen/PrologEpilogInserter.cpp @@ -175,9 +175,10 @@ void PEI::calculateCallsInformation(MachineFunction &Fn) { MachineBasicBlock::iterator I = *i; // If call frames are not being included as part of the stack frame, and - // there is no dynamic allocation (therefore referencing frame slots off - // sp), leave the pseudo ops alone. We'll eliminate them later. - if (RegInfo->hasReservedCallFrame(Fn) || RegInfo->hasFP(Fn)) + // the target doesn't indicate otherwise, remove the call frame pseudos + // here. The sub/add sp instruction pairs are still inserted, but we don't + // need to track the SP adjustment for frame index elimination. + if (RegInfo->canSimplifyCallFramePseudos(Fn)) RegInfo->eliminateCallFramePseudoInstr(Fn, *I->getParent(), I); } } diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.cpp b/lib/Target/ARM/ARMBaseRegisterInfo.cpp index 91e3550d077..e1c493ac63e 100644 --- a/lib/Target/ARM/ARMBaseRegisterInfo.cpp +++ b/lib/Target/ARM/ARMBaseRegisterInfo.cpp @@ -1085,6 +1085,16 @@ hasReservedCallFrame(MachineFunction &MF) const { return !MF.getFrameInfo()->hasVarSizedObjects(); } +// canSimplifyCallFramePseudos - If there is a reserved call frame, the +// call frame pseudos can be simplified. Unlike most targets, having a FP +// is not sufficient here since we still may reference some objects via SP +// even when FP is available in Thumb2 mode. +bool ARMBaseRegisterInfo:: +canSimplifyCallFramePseudos(MachineFunction &MF) const { + ARMFunctionInfo *AFI = MF.getInfo(); + return hasReservedCallFrame(MF) || (AFI->isThumb1OnlyFunction() && hasFP(MF)); +} + static void emitSPUpdate(bool isARM, MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, @@ -1149,7 +1159,6 @@ ARMBaseRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, MachineInstr &MI = *II; MachineBasicBlock &MBB = *MI.getParent(); MachineFunction &MF = *MBB.getParent(); - const MachineFrameInfo *MFI = MF.getFrameInfo(); ARMFunctionInfo *AFI = MF.getInfo(); assert(!AFI->isThumb1OnlyFunction() && "This eliminateFrameIndex does not support Thumb1!"); @@ -1160,12 +1169,12 @@ ARMBaseRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, } int FrameIndex = MI.getOperand(i).getIndex(); - int Offset = MFI->getObjectOffset(FrameIndex) + MFI->getStackSize() + SPAdj; unsigned FrameReg; - Offset = getFrameIndexReference(MF, FrameIndex, FrameReg); + int Offset = getFrameIndexReference(MF, FrameIndex, FrameReg); if (FrameReg != ARM::SP) SPAdj = 0; + Offset += SPAdj; // Modify MI as necessary to handle as much of 'Offset' as possible bool Done = false; diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.h b/lib/Target/ARM/ARMBaseRegisterInfo.h index 33ba21dcb8f..64f6ff1cb3d 100644 --- a/lib/Target/ARM/ARMBaseRegisterInfo.h +++ b/lib/Target/ARM/ARMBaseRegisterInfo.h @@ -138,6 +138,7 @@ public: virtual bool requiresFrameIndexScavenging(const MachineFunction &MF) const; virtual bool hasReservedCallFrame(MachineFunction &MF) const; + virtual bool canSimplifyCallFramePseudos(MachineFunction &MF) const; virtual void eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,