refactor some code to avoid overloading the name 'usesLR' in

different places to mean different things.  Document what the
one in PPCFunctionInfo means and when it is valid.

llvm-svn: 44699
This commit is contained in:
Chris Lattner 2007-12-08 06:39:11 +00:00
parent 1ebfecc8d0
commit a6c8297e84
3 changed files with 14 additions and 12 deletions

View File

@ -39,8 +39,12 @@ public:
int getFramePointerSaveIndex() const { return FramePointerSaveIndex; }
void setFramePointerSaveIndex(int Idx) { FramePointerSaveIndex = Idx; }
/// UsesLR - This is set when the prolog/epilog inserter does its initial scan
/// of the function, it is true if the LR/LR8 register is ever explicitly
/// accessed/clobbered in the machine function (e.g. by calls and movpctolr,
/// which is used in PIC generation).
void setUsesLR(bool U) { UsesLR = U; }
bool usesLR() { return UsesLR; }
bool usesLR() const { return UsesLR; }
};

View File

@ -645,11 +645,13 @@ bool PPCRegisterInfo::hasFP(const MachineFunction &MF) const {
return MFI->getStackSize() && needsFP(MF);
}
/// usesLR - Returns if the link registers (LR) has been used in the function.
///
bool PPCRegisterInfo::usesLR(MachineFunction &MF) const {
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
return FI->usesLR();
/// MustSaveLR - Return true if this function requires that we save the LR
/// register onto the stack in the prolog and restore it in the epilog of the function.
static bool MustSaveLR(const MachineFunction &MF) {
return MF.getInfo<PPCFunctionInfo>()->usesLR() ||
// FIXME: Anything that has a call should clobber the LR register,
// isn't this redundant??
MF.getFrameInfo()->hasCalls();
}
void PPCRegisterInfo::
@ -1062,7 +1064,7 @@ void PPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
// Get operating system
bool IsMachoABI = Subtarget.isMachoABI();
// Check if the link register (LR) has been used.
bool UsesLR = MFI->hasCalls() || usesLR(MF);
bool UsesLR = MustSaveLR(MF);
// Do we have a frame pointer for this function?
bool HasFP = hasFP(MF) && FrameSize;
@ -1226,7 +1228,7 @@ void PPCRegisterInfo::emitEpilogue(MachineFunction &MF,
// Get operating system
bool IsMachoABI = Subtarget.isMachoABI();
// Check if the link register (LR) has been used.
bool UsesLR = MFI->hasCalls() || usesLR(MF);
bool UsesLR = MustSaveLR(MF);
// Do we have a frame pointer for this function?
bool HasFP = hasFP(MF) && FrameSize;

View File

@ -96,10 +96,6 @@ public:
MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const;
/// usesLR - Returns if the link registers (LR) has been used in the function.
///
bool usesLR(MachineFunction &MF) const;
void lowerDynamicAlloc(MachineBasicBlock::iterator II) const;
void eliminateFrameIndex(MachineBasicBlock::iterator II,
int SPAdj, RegScavenger *RS = NULL) const;