Do not use frame register to reference fixed stack objects if the function is frameless.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79067 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.cpp b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
index 12fbb5d..09ab87c 100644
--- a/lib/Target/ARM/ARMBaseRegisterInfo.cpp
+++ b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
@@ -440,7 +440,7 @@
MFI->isFrameAddressTaken());
}
-bool ARMBaseRegisterInfo::hasStackFrame(const MachineFunction &MF) const {
+bool ARMBaseRegisterInfo::cannotEliminateFrame(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
if (NoFramePointerElim && MFI->hasCalls())
return true;
@@ -596,7 +596,7 @@
}
bool ExtraCSSpill = false;
- if (!CanEliminateFrame || hasStackFrame(MF)) {
+ if (!CanEliminateFrame || cannotEliminateFrame(MF)) {
AFI->setHasStackFrame(true);
// If LR is not spilled, but at least one of R4, R5, R6, and R7 is spilled.
@@ -1022,6 +1022,7 @@
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 suppor Thumb1!");
@@ -1033,8 +1034,7 @@
unsigned FrameReg = ARM::SP;
int FrameIndex = MI.getOperand(i).getIndex();
- int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
- MF.getFrameInfo()->getStackSize() + SPAdj;
+ int Offset = MFI->getObjectOffset(FrameIndex) + MFI->getStackSize() + SPAdj;
if (AFI->isGPRCalleeSavedArea1Frame(FrameIndex))
Offset -= AFI->getGPRCalleeSavedArea1Offset();
@@ -1042,10 +1042,10 @@
Offset -= AFI->getGPRCalleeSavedArea2Offset();
else if (AFI->isDPRCalleeSavedAreaFrame(FrameIndex))
Offset -= AFI->getDPRCalleeSavedAreaOffset();
- else if (hasFP(MF)) {
- assert(SPAdj == 0 && "Unexpected");
- // There is alloca()'s in this function, must reference off the frame
- // pointer instead.
+ else if (hasFP(MF) && AFI->hasStackFrame()) {
+ assert(SPAdj == 0 && "Unexpected stack offset!");
+ // Use frame pointer to reference fixed objects unless this is a
+ // frameless function,
FrameReg = getFrameRegister(MF);
Offset -= AFI->getFramePtrSpillOffset();
}
@@ -1288,14 +1288,15 @@
// Darwin ABI requires FP to point to the stack slot that contains the
// previous FP.
- if ((STI.isTargetDarwin() && NumBytes) || hasFP(MF)) {
+ bool HasFP = hasFP(MF);
+ if ((STI.isTargetDarwin() && NumBytes) || HasFP) {
NumBytes = AFI->getFramePtrSpillOffset() - NumBytes;
// Reset SP based on frame pointer only if the stack frame extends beyond
// frame pointer stack slot or target is ELF and the function has FP.
- if (AFI->getGPRCalleeSavedArea2Size() ||
+ if (HasFP ||
+ AFI->getGPRCalleeSavedArea2Size() ||
AFI->getDPRCalleeSavedAreaSize() ||
- AFI->getDPRCalleeSavedAreaOffset()||
- hasFP(MF)) {
+ AFI->getDPRCalleeSavedAreaOffset()) {
if (NumBytes) {
if (isARM)
emitARMRegPlusImmediate(MBB, MBBI, dl, ARM::SP, FramePtr, -NumBytes,
diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.h b/lib/Target/ARM/ARMBaseRegisterInfo.h
index c242489..3eccab0 100644
--- a/lib/Target/ARM/ARMBaseRegisterInfo.h
+++ b/lib/Target/ARM/ARMBaseRegisterInfo.h
@@ -89,7 +89,7 @@
bool hasFP(const MachineFunction &MF) const;
- bool hasStackFrame(const MachineFunction &MF) const;
+ bool cannotEliminateFrame(const MachineFunction &MF) const;
void processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
RegScavenger *RS = NULL) const;