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Diffstat (limited to 'lib/Target/ARM/ARMBaseRegisterInfo.cpp')
-rw-r--r--lib/Target/ARM/ARMBaseRegisterInfo.cpp119
1 files changed, 61 insertions, 58 deletions
diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.cpp b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
index cb0bd1d..577c363 100644
--- a/lib/Target/ARM/ARMBaseRegisterInfo.cpp
+++ b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
@@ -513,7 +513,7 @@ cannotEliminateFrame(const MachineFunction &MF) const {
}
/// estimateStackSize - Estimate and return the size of the frame.
-static unsigned estimateStackSize(MachineFunction &MF, MachineFrameInfo *MFI) {
+static unsigned estimateStackSize(MachineFunction &MF) {
const MachineFrameInfo *FFI = MF.getFrameInfo();
int Offset = 0;
for (int i = FFI->getObjectIndexBegin(); i != 0; ++i) {
@@ -583,14 +583,6 @@ ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
SmallVector<unsigned, 4> UnspilledCS2GPRs;
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
-
- // Calculate and set max stack object alignment early, so we can decide
- // whether we will need stack realignment (and thus FP).
- if (RealignStack) {
- MachineFrameInfo *MFI = MF.getFrameInfo();
- MFI->calculateMaxStackAlignment();
- }
-
// Spill R4 if Thumb2 function requires stack realignment - it will be used as
// scratch register.
// FIXME: It will be better just to find spare register here.
@@ -679,8 +671,16 @@ ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
}
}
+ // If any of the stack slot references may be out of range of an immediate
+ // offset, make sure a register (or a spill slot) is available for the
+ // register scavenger. Note that if we're indexing off the frame pointer, the
+ // effective stack size is 4 bytes larger since the FP points to the stack
+ // slot of the previous FP.
+ bool BigStack = RS &&
+ estimateStackSize(MF) + (hasFP(MF) ? 4 : 0) >= estimateRSStackSizeLimit(MF);
+
bool ExtraCSSpill = false;
- if (!CanEliminateFrame || cannotEliminateFrame(MF)) {
+ if (BigStack || !CanEliminateFrame || cannotEliminateFrame(MF)) {
AFI->setHasStackFrame(true);
// If LR is not spilled, but at least one of R4, R5, R6, and R7 is spilled.
@@ -735,51 +735,43 @@ ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
// callee-saved register or reserve a special spill slot to facilitate
// register scavenging. Thumb1 needs a spill slot for stack pointer
// adjustments also, even when the frame itself is small.
- if (RS && !ExtraCSSpill) {
- MachineFrameInfo *MFI = MF.getFrameInfo();
- // If any of the stack slot references may be out of range of an
- // immediate offset, make sure a register (or a spill slot) is
- // available for the register scavenger. Note that if we're indexing
- // off the frame pointer, the effective stack size is 4 bytes larger
- // since the FP points to the stack slot of the previous FP.
- if (estimateStackSize(MF, MFI) + (hasFP(MF) ? 4 : 0)
- >= estimateRSStackSizeLimit(MF)) {
- // If any non-reserved CS register isn't spilled, just spill one or two
- // extra. That should take care of it!
- unsigned NumExtras = TargetAlign / 4;
- SmallVector<unsigned, 2> Extras;
- while (NumExtras && !UnspilledCS1GPRs.empty()) {
- unsigned Reg = UnspilledCS1GPRs.back();
- UnspilledCS1GPRs.pop_back();
+ if (BigStack && !ExtraCSSpill) {
+ // If any non-reserved CS register isn't spilled, just spill one or two
+ // extra. That should take care of it!
+ unsigned NumExtras = TargetAlign / 4;
+ SmallVector<unsigned, 2> Extras;
+ while (NumExtras && !UnspilledCS1GPRs.empty()) {
+ unsigned Reg = UnspilledCS1GPRs.back();
+ UnspilledCS1GPRs.pop_back();
+ if (!isReservedReg(MF, Reg)) {
+ Extras.push_back(Reg);
+ NumExtras--;
+ }
+ }
+ // For non-Thumb1 functions, also check for hi-reg CS registers
+ if (!AFI->isThumb1OnlyFunction()) {
+ while (NumExtras && !UnspilledCS2GPRs.empty()) {
+ unsigned Reg = UnspilledCS2GPRs.back();
+ UnspilledCS2GPRs.pop_back();
if (!isReservedReg(MF, Reg)) {
Extras.push_back(Reg);
NumExtras--;
}
}
- // For non-Thumb1 functions, also check for hi-reg CS registers
- if (!AFI->isThumb1OnlyFunction()) {
- while (NumExtras && !UnspilledCS2GPRs.empty()) {
- unsigned Reg = UnspilledCS2GPRs.back();
- UnspilledCS2GPRs.pop_back();
- if (!isReservedReg(MF, Reg)) {
- Extras.push_back(Reg);
- NumExtras--;
- }
- }
- }
- if (Extras.size() && NumExtras == 0) {
- for (unsigned i = 0, e = Extras.size(); i != e; ++i) {
- MF.getRegInfo().setPhysRegUsed(Extras[i]);
- AFI->setCSRegisterIsSpilled(Extras[i]);
- }
- } else if (!AFI->isThumb1OnlyFunction()) {
- // note: Thumb1 functions spill to R12, not the stack.
- // Reserve a slot closest to SP or frame pointer.
- const TargetRegisterClass *RC = ARM::GPRRegisterClass;
- RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
- RC->getAlignment(),
- false));
+ }
+ if (Extras.size() && NumExtras == 0) {
+ for (unsigned i = 0, e = Extras.size(); i != e; ++i) {
+ MF.getRegInfo().setPhysRegUsed(Extras[i]);
+ AFI->setCSRegisterIsSpilled(Extras[i]);
}
+ } else if (!AFI->isThumb1OnlyFunction()) {
+ // note: Thumb1 functions spill to R12, not the stack. Reserve a slot
+ // closest to SP or frame pointer.
+ const TargetRegisterClass *RC = ARM::GPRRegisterClass;
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
+ RC->getAlignment(),
+ false));
}
}
}
@@ -1093,6 +1085,15 @@ 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 {
+ return hasReservedCallFrame(MF) || MF.getFrameInfo()->hasVarSizedObjects();
+}
+
static void
emitSPUpdate(bool isARM,
MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
@@ -1127,13 +1128,14 @@ eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
- "This eliminateCallFramePseudoInstr does not suppor Thumb1!");
+ "This eliminateCallFramePseudoInstr does not support Thumb1!");
bool isARM = !AFI->isThumbFunction();
// Replace the pseudo instruction with a new instruction...
unsigned Opc = Old->getOpcode();
- ARMCC::CondCodes Pred = (ARMCC::CondCodes)Old->getOperand(1).getImm();
- // FIXME: Thumb2 version of ADJCALLSTACKUP and ADJCALLSTACKDOWN?
+ int PIdx = Old->findFirstPredOperandIdx();
+ ARMCC::CondCodes Pred = (PIdx == -1)
+ ? ARMCC::AL : (ARMCC::CondCodes)Old->getOperand(PIdx).getImm();
if (Opc == ARM::ADJCALLSTACKDOWN || Opc == ARM::tADJCALLSTACKDOWN) {
// Note: PredReg is operand 2 for ADJCALLSTACKDOWN.
unsigned PredReg = Old->getOperand(2).getReg();
@@ -1157,7 +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<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
"This eliminateFrameIndex does not support Thumb1!");
@@ -1168,12 +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;
@@ -1264,7 +1265,7 @@ emitPrologue(MachineFunction &MF) const {
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
- "This emitPrologue does not suppor Thumb1!");
+ "This emitPrologue does not support Thumb1!");
bool isARM = !AFI->isThumbFunction();
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
unsigned NumBytes = MFI->getStackSize();
@@ -1349,7 +1350,9 @@ emitPrologue(MachineFunction &MF) const {
unsigned DPRCSOffset = NumBytes - (GPRCS1Size + GPRCS2Size + DPRCSSize);
unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
- AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) + NumBytes);
+ if (STI.isTargetDarwin() || hasFP(MF))
+ AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) +
+ NumBytes);
AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);
@@ -1425,7 +1428,7 @@ emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const {
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
- "This emitEpilogue does not suppor Thumb1!");
+ "This emitEpilogue does not support Thumb1!");
bool isARM = !AFI->isThumbFunction();
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
generated by cgit v1.1 at 2024-06-04 06:43:18 +0000