PPCFrameLowering's FramePointerOffset can be computed at initialization

time. Do so.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228998 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Christopher 2015-02-13 00:39:38 +00:00
parent 82eeeb5b94
commit 2b4e1b9abf
3 changed files with 25 additions and 28 deletions

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@ -47,11 +47,25 @@ static unsigned computeTOCSaveOffset(const PPCSubtarget &STI) {
return STI.isELFv2ABI() ? 24 : 40;
}
static unsigned computeFramePointerSaveOffset(const PPCSubtarget &STI) {
// For the Darwin ABI:
// We cannot use the TOC save slot (offset +20) in the PowerPC linkage area
// for saving the frame pointer (if needed.) While the published ABI has
// not used this slot since at least MacOSX 10.2, there is older code
// around that does use it, and that needs to continue to work.
if (STI.isDarwinABI())
return STI.isPPC64() ? -8U : -4U;
// SVR4 ABI: First slot in the general register save area.
return STI.isPPC64() ? -8U : -4U;
}
PPCFrameLowering::PPCFrameLowering(const PPCSubtarget &STI)
: TargetFrameLowering(TargetFrameLowering::StackGrowsDown,
(STI.hasQPX() || STI.isBGQ()) ? 32 : 16, 0),
Subtarget(STI), ReturnSaveOffset(computeReturnSaveOffset(Subtarget)),
TOCSaveOffset(computeTOCSaveOffset(Subtarget)) {}
TOCSaveOffset(computeTOCSaveOffset(Subtarget)),
FramePointerSaveOffset(computeFramePointerSaveOffset(Subtarget)) {}
// With the SVR4 ABI, callee-saved registers have fixed offsets on the stack.
const PPCFrameLowering::SpillSlot *PPCFrameLowering::getCalleeSavedSpillSlots(
@ -620,8 +634,7 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const {
assert(FPIndex && "No Frame Pointer Save Slot!");
FPOffset = FFI->getObjectOffset(FPIndex);
} else {
FPOffset =
PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
FPOffset = getFramePointerSaveOffset();
}
}
@ -958,8 +971,7 @@ void PPCFrameLowering::emitEpilogue(MachineFunction &MF,
assert(FPIndex && "No Frame Pointer Save Slot!");
FPOffset = FFI->getObjectOffset(FPIndex);
} else {
FPOffset =
PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
FPOffset = getFramePointerSaveOffset();
}
}
@ -1159,7 +1171,7 @@ PPCFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
// If the frame pointer save index hasn't been defined yet.
if (!FPSI && needsFP(MF)) {
// Find out what the fix offset of the frame pointer save area.
int FPOffset = getFramePointerSaveOffset(isPPC64, isDarwinABI);
int FPOffset = getFramePointerSaveOffset();
// Allocate the frame index for frame pointer save area.
FPSI = MFI->CreateFixedObject(isPPC64? 8 : 4, FPOffset, true);
// Save the result.

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@ -25,6 +25,7 @@ class PPCFrameLowering: public TargetFrameLowering {
const PPCSubtarget &Subtarget;
const unsigned ReturnSaveOffset;
const unsigned TOCSaveOffset;
const unsigned FramePointerSaveOffset;
public:
PPCFrameLowering(const PPCSubtarget &STI);
@ -77,18 +78,7 @@ public:
/// getFramePointerSaveOffset - Return the previous frame offset to save the
/// frame pointer.
static unsigned getFramePointerSaveOffset(bool isPPC64, bool isDarwinABI) {
// For the Darwin ABI:
// We cannot use the TOC save slot (offset +20) in the PowerPC linkage area
// for saving the frame pointer (if needed.) While the published ABI has
// not used this slot since at least MacOSX 10.2, there is older code
// around that does use it, and that needs to continue to work.
if (isDarwinABI)
return isPPC64 ? -8U : -4U;
// SVR4 ABI: First slot in the general register save area.
return isPPC64 ? -8U : -4U;
}
unsigned getFramePointerSaveOffset() const { return FramePointerSaveOffset; }
/// getBasePointerSaveOffset - Return the previous frame offset to save the
/// base pointer.

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@ -3472,10 +3472,9 @@ static SDValue EmitTailCallStoreFPAndRetAddr(SelectionDAG &DAG,
if (SPDiff) {
// Calculate the new stack slot for the return address.
int SlotSize = isPPC64 ? 8 : 4;
int NewRetAddrLoc = SPDiff +
MF.getSubtarget<PPCSubtarget>()
.getFrameLowering()
->getReturnSaveOffset();
const PPCFrameLowering *FL =
MF.getSubtarget<PPCSubtarget>().getFrameLowering();
int NewRetAddrLoc = SPDiff + FL->getReturnSaveOffset();
int NewRetAddr = MF.getFrameInfo()->CreateFixedObject(SlotSize,
NewRetAddrLoc, true);
EVT VT = isPPC64 ? MVT::i64 : MVT::i32;
@ -3487,8 +3486,7 @@ static SDValue EmitTailCallStoreFPAndRetAddr(SelectionDAG &DAG,
// When using the 32/64-bit SVR4 ABI there is no need to move the FP stack
// slot as the FP is never overwritten.
if (isDarwinABI) {
int NewFPLoc =
SPDiff + PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
int NewFPLoc = SPDiff + FL->getFramePointerSaveOffset();
int NewFPIdx = MF.getFrameInfo()->CreateFixedObject(SlotSize, NewFPLoc,
true);
SDValue NewFramePtrIdx = DAG.getFrameIndex(NewFPIdx, VT);
@ -5332,7 +5330,6 @@ SDValue
PPCTargetLowering::getFramePointerFrameIndex(SelectionDAG & DAG) const {
MachineFunction &MF = DAG.getMachineFunction();
bool isPPC64 = Subtarget.isPPC64();
bool isDarwinABI = Subtarget.isDarwinABI();
EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
// Get current frame pointer save index. The users of this index will be
@ -5343,9 +5340,7 @@ PPCTargetLowering::getFramePointerFrameIndex(SelectionDAG & DAG) const {
// If the frame pointer save index hasn't been defined yet.
if (!FPSI) {
// Find out what the fix offset of the frame pointer save area.
int FPOffset = PPCFrameLowering::getFramePointerSaveOffset(isPPC64,
isDarwinABI);
int FPOffset = Subtarget.getFrameLowering()->getFramePointerSaveOffset();
// Allocate the frame index for frame pointer save area.
FPSI = MF.getFrameInfo()->CreateFixedObject(isPPC64? 8 : 4, FPOffset, true);
// Save the result.