}
// Have we generated a STUX instruction to claim stack frame? If so,
- // the frame size will be placed in ScratchReg.
+ // the negated frame size will be placed in ScratchReg.
bool HasSTUX = false;
// This condition must be kept in sync with canUseAsPrologue.
if (!HasRedZone) {
assert(!isPPC64 && "A red zone is always available on PPC64");
if (HasSTUX) {
- // The frame size is in ScratchReg, and the SPReg has been advanced
- // (downwards) by the frame size: SPReg = old SPReg + ScratchReg.
- // Set ScratchReg to the original SPReg: ScratchReg = SPReg - ScratchReg.
+ // The negated frame size is in ScratchReg, and the SPReg has been
+ // decremented by the frame size: SPReg = old SPReg + ScratchReg.
+ // Since FPOffset, PBPOffset, etc. are relative to the beginning of
+ // the stack frame (i.e. the old SP), ideally, we would put the old
+ // SP into a register and use it as the base for the stores. The
+ // problem is that the only available register may be ScratchReg,
+ // which could be R0, and R0 cannot be used as a base address.
+
+ // First, set ScratchReg to the old SP. This may need to be modified
+ // later.
BuildMI(MBB, MBBI, dl, TII.get(PPC::SUBF), ScratchReg)
.addReg(ScratchReg, RegState::Kill)
.addReg(SPReg);
- // Now that the stack frame has been allocated, save all the necessary
- // registers using ScratchReg as the base address.
- if (HasFP)
- BuildMI(MBB, MBBI, dl, StoreInst)
- .addReg(FPReg)
- .addImm(FPOffset)
- .addReg(ScratchReg);
- if (FI->usesPICBase())
- BuildMI(MBB, MBBI, dl, StoreInst)
- .addReg(PPC::R30)
- .addImm(PBPOffset)
- .addReg(ScratchReg);
- if (HasBP) {
- BuildMI(MBB, MBBI, dl, StoreInst)
- .addReg(BPReg)
- .addImm(BPOffset)
- .addReg(ScratchReg);
- BuildMI(MBB, MBBI, dl, OrInst, BPReg)
- .addReg(ScratchReg, RegState::Kill)
- .addReg(ScratchReg);
+ if (ScratchReg == PPC::R0) {
+ // R0 cannot be used as a base register, but it can be used as an
+ // index in a store-indexed.
+ int LastOffset = 0;
+ if (HasFP) {
+ // R0 += (FPOffset-LastOffset).
+ // Need addic, since addi treats R0 as 0.
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDIC), ScratchReg)
+ .addReg(ScratchReg)
+ .addImm(FPOffset-LastOffset);
+ LastOffset = FPOffset;
+ // Store FP into *R0.
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STWX))
+ .addReg(FPReg, RegState::Kill) // Save FP.
+ .addReg(PPC::ZERO)
+ .addReg(ScratchReg); // This will be the index (R0 is ok here).
+ }
+ if (FI->usesPICBase()) {
+ // R0 += (PBPOffset-LastOffset).
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDIC), ScratchReg)
+ .addReg(ScratchReg)
+ .addImm(PBPOffset-LastOffset);
+ LastOffset = PBPOffset;
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STWX))
+ .addReg(PPC::R30, RegState::Kill) // Save PIC base pointer.
+ .addReg(PPC::ZERO)
+ .addReg(ScratchReg); // This will be the index (R0 is ok here).
+ }
+ if (HasBP) {
+ // R0 += (BPOffset-LastOffset).
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDIC), ScratchReg)
+ .addReg(ScratchReg)
+ .addImm(BPOffset-LastOffset);
+ LastOffset = BPOffset;
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STWX))
+ .addReg(BPReg, RegState::Kill) // Save BP.
+ .addReg(PPC::ZERO)
+ .addReg(ScratchReg); // This will be the index (R0 is ok here).
+ // BP = R0-LastOffset
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDIC), BPReg)
+ .addReg(ScratchReg, RegState::Kill)
+ .addImm(-LastOffset);
+ }
+ } else {
+ // ScratchReg is not R0, so use it as the base register. It is
+ // already set to the old SP, so we can use the offsets directly.
+
+ // Now that the stack frame has been allocated, save all the necessary
+ // registers using ScratchReg as the base address.
+ if (HasFP)
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(FPReg)
+ .addImm(FPOffset)
+ .addReg(ScratchReg);
+ if (FI->usesPICBase())
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(PPC::R30)
+ .addImm(PBPOffset)
+ .addReg(ScratchReg);
+ if (HasBP) {
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(BPReg)
+ .addImm(BPOffset)
+ .addReg(ScratchReg);
+ BuildMI(MBB, MBBI, dl, OrInst, BPReg)
+ .addReg(ScratchReg, RegState::Kill)
+ .addReg(ScratchReg);
+ }
}
} else {
// The frame size is a known 16-bit constant (fitting in the immediate
// Do we have a frame pointer and/or base pointer for this function?
bool HasFP = hasFP(MF);
bool HasBP = RegInfo->hasBasePointer(MF);
+ bool HasRedZone = Subtarget.isPPC64() || !Subtarget.isSVR4ABI();
unsigned SPReg = isPPC64 ? PPC::X1 : PPC::R1;
unsigned BPReg = RegInfo->getBaseRegister(MF);
: PPC::LWZ );
const MCInstrDesc& LoadImmShiftedInst = TII.get( isPPC64 ? PPC::LIS8
: PPC::LIS );
+ const MCInstrDesc& OrInst = TII.get(isPPC64 ? PPC::OR8
+ : PPC::OR );
const MCInstrDesc& OrImmInst = TII.get( isPPC64 ? PPC::ORI8
: PPC::ORI );
const MCInstrDesc& AddImmInst = TII.get( isPPC64 ? PPC::ADDI8
if (HasFP) {
if (isSVR4ABI) {
- MachineFrameInfo &MFI = MF.getFrameInfo();
int FPIndex = FI->getFramePointerSaveIndex();
assert(FPIndex && "No Frame Pointer Save Slot!");
FPOffset = MFI.getObjectOffset(FPIndex);
int BPOffset = 0;
if (HasBP) {
if (isSVR4ABI) {
- MachineFrameInfo &MFI = MF.getFrameInfo();
int BPIndex = FI->getBasePointerSaveIndex();
assert(BPIndex && "No Base Pointer Save Slot!");
BPOffset = MFI.getObjectOffset(BPIndex);
int PBPOffset = 0;
if (FI->usesPICBase()) {
- MachineFrameInfo &MFI = MF.getFrameInfo();
int PBPIndex = FI->getPICBasePointerSaveIndex();
assert(PBPIndex && "No PIC Base Pointer Save Slot!");
PBPOffset = MFI.getObjectOffset(PBPIndex);
// indexed into with a simple LD/LWZ immediate offset operand.
bool isLargeFrame = !isInt<16>(FrameSize);
+ // On targets without red zone, the SP needs to be restored last, so that
+ // all live contents of the stack frame are upwards of the SP. This means
+ // that we cannot restore SP just now, since there may be more registers
+ // to restore from the stack frame (e.g. R31). If the frame size is not
+ // a simple immediate value, we will need a spare register to hold the
+ // restored SP. If the frame size is known and small, we can simply adjust
+ // the offsets of the registers to be restored, and still use SP to restore
+ // them. In such case, the final update of SP will be to add the frame
+ // size to it.
+ // To simplify the code, set RBReg to the base register used to restore
+ // values from the stack, and set SPAdd to the value that needs to be added
+ // to the SP at the end. The default values are as if red zone was present.
+ unsigned RBReg = SPReg;
+ unsigned SPAdd = 0;
+
if (FrameSize) {
- // In the prologue, the loaded (or persistent) stack pointer value is offset
- // by the STDU/STDUX/STWU/STWUX instruction. Add this offset back now.
+ // In the prologue, the loaded (or persistent) stack pointer value is
+ // offset by the STDU/STDUX/STWU/STWUX instruction. For targets with red
+ // zone add this offset back now.
// If this function contained a fastcc call and GuaranteedTailCallOpt is
// enabled (=> hasFastCall()==true) the fastcc call might contain a tail
// value of R31 in this case.
if (FI->hasFastCall()) {
assert(HasFP && "Expecting a valid frame pointer.");
+ if (!HasRedZone)
+ RBReg = FPReg;
if (!isLargeFrame) {
- BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ BuildMI(MBB, MBBI, dl, AddImmInst, RBReg)
.addReg(FPReg).addImm(FrameSize);
} else {
BuildMI(MBB, MBBI, dl, LoadImmShiftedInst, ScratchReg)
.addReg(ScratchReg, RegState::Kill)
.addImm(FrameSize & 0xFFFF);
BuildMI(MBB, MBBI, dl, AddInst)
- .addReg(SPReg)
+ .addReg(RBReg)
.addReg(FPReg)
.addReg(ScratchReg);
}
} else if (!isLargeFrame && !HasBP && !MFI.hasVarSizedObjects()) {
- BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
- .addReg(SPReg)
- .addImm(FrameSize);
+ if (HasRedZone) {
+ BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ .addReg(SPReg)
+ .addImm(FrameSize);
+ } else {
+ // Make sure that adding FrameSize will not overflow the max offset
+ // size.
+ assert(FPOffset <= 0 && BPOffset <= 0 && PBPOffset <= 0 &&
+ "Local offsets should be negative");
+ SPAdd = FrameSize;
+ FPOffset += FrameSize;
+ BPOffset += FrameSize;
+ PBPOffset += FrameSize;
+ }
} else {
- BuildMI(MBB, MBBI, dl, LoadInst, SPReg)
+ // We don't want to use ScratchReg as a base register, because it
+ // could happen to be R0. Use FP instead, but make sure to preserve it.
+ if (!HasRedZone) {
+ // If FP is not saved, copy it to ScratchReg.
+ if (!HasFP)
+ BuildMI(MBB, MBBI, dl, OrInst, ScratchReg)
+ .addReg(FPReg)
+ .addReg(FPReg);
+ RBReg = FPReg;
+ }
+ BuildMI(MBB, MBBI, dl, LoadInst, RBReg)
.addImm(0)
.addReg(SPReg);
}
}
+ assert(RBReg != ScratchReg && "Should have avoided ScratchReg");
+ // If there is no red zone, ScratchReg may be needed for holding a useful
+ // value (although not the base register). Make sure it is not overwritten
+ // too early.
assert((isPPC64 || !MustSaveCR) &&
"Epilogue CR restoring supported only in 64-bit mode");
- // If we need to save both the LR and the CR and we only have one available
- // scratch register, we must do them one at a time.
+ // If we need to restore both the LR and the CR and we only have one
+ // available scratch register, we must do them one at a time.
if (MustSaveCR && SingleScratchReg && MustSaveLR) {
+ // Here TempReg == ScratchReg, and in the absence of red zone ScratchReg
+ // is live here.
+ assert(HasRedZone && "Expecting red zone");
BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ8), TempReg)
.addImm(8)
.addReg(SPReg);
.addReg(TempReg, getKillRegState(i == e-1));
}
- if (MustSaveLR)
+ // Delay restoring of the LR if ScratchReg is needed. This is ok, since
+ // LR is stored in the caller's stack frame. ScratchReg will be needed
+ // if RBReg is anything other than SP. We shouldn't use ScratchReg as
+ // a base register anyway, because it may happen to be R0.
+ bool LoadedLR = false;
+ if (MustSaveLR && RBReg == SPReg && isInt<16>(LROffset+SPAdd)) {
BuildMI(MBB, MBBI, dl, LoadInst, ScratchReg)
- .addImm(LROffset)
- .addReg(SPReg);
+ .addImm(LROffset+SPAdd)
+ .addReg(RBReg);
+ LoadedLR = true;
+ }
- if (MustSaveCR &&
- !(SingleScratchReg && MustSaveLR)) // will only occur for PPC64
+ if (MustSaveCR && !(SingleScratchReg && MustSaveLR)) {
+ // This will only occur for PPC64.
+ assert(isPPC64 && "Expecting 64-bit mode");
+ assert(RBReg == SPReg && "Should be using SP as a base register");
BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ8), TempReg)
.addImm(8)
- .addReg(SPReg);
+ .addReg(RBReg);
+ }
- if (HasFP)
- BuildMI(MBB, MBBI, dl, LoadInst, FPReg)
- .addImm(FPOffset)
- .addReg(SPReg);
+ if (HasFP) {
+ // If there is red zone, restore FP directly, since SP has already been
+ // restored. Otherwise, restore the value of FP into ScratchReg.
+ if (HasRedZone || RBReg == SPReg)
+ BuildMI(MBB, MBBI, dl, LoadInst, FPReg)
+ .addImm(FPOffset)
+ .addReg(SPReg);
+ else
+ BuildMI(MBB, MBBI, dl, LoadInst, ScratchReg)
+ .addImm(FPOffset)
+ .addReg(RBReg);
+ }
if (FI->usesPICBase())
- // FIXME: On PPC32 SVR4, we must not spill before claiming the stackframe.
BuildMI(MBB, MBBI, dl, LoadInst)
.addReg(PPC::R30)
.addImm(PBPOffset)
- .addReg(SPReg);
+ .addReg(RBReg);
if (HasBP)
BuildMI(MBB, MBBI, dl, LoadInst, BPReg)
.addImm(BPOffset)
- .addReg(SPReg);
+ .addReg(RBReg);
+
+ // There is nothing more to be loaded from the stack, so now we can
+ // restore SP: SP = RBReg + SPAdd.
+ if (RBReg != SPReg || SPAdd != 0) {
+ assert(!HasRedZone && "This should not happen with red zone");
+ // If SPAdd is 0, generate a copy.
+ if (SPAdd == 0)
+ BuildMI(MBB, MBBI, dl, OrInst, SPReg)
+ .addReg(RBReg)
+ .addReg(RBReg);
+ else
+ BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ .addReg(RBReg)
+ .addImm(SPAdd);
+
+ assert(RBReg != ScratchReg && "Should be using FP or SP as base register");
+ if (RBReg == FPReg)
+ BuildMI(MBB, MBBI, dl, OrInst, FPReg)
+ .addReg(ScratchReg)
+ .addReg(ScratchReg);
+
+ // Now load the LR from the caller's stack frame.
+ if (MustSaveLR && !LoadedLR)
+ BuildMI(MBB, MBBI, dl, LoadInst, ScratchReg)
+ .addImm(LROffset)
+ .addReg(SPReg);
+ }
if (MustSaveCR &&
!(SingleScratchReg && MustSaveLR)) // will only occur for PPC64
--- /dev/null
+; Test that accesses of the stack remain within the range defined by R1,
+; i.e. that loads and stores only access the allocated stack. This does not
+; have to be the case when red zone is present.
+
+; Make sure that there is no red zone, i.e. ppc32 and SVR4 ABI.
+; RUN: llc -mtriple=powerpc--freebsd-elf < %s | FileCheck %s
+
+; There are two ways that the stack pointer can be adjusted in the prologue:
+; - by adding an immediate value:
+; stwu r1, -imm(r1)
+; - by adding another register:
+; stwux r1, rx, r1
+;
+; The restoring of the stack pointer can be done:
+; - by adding an immediate value to it:
+; addi r1, r1, imm
+; - by copying the value from another register:
+; mr r1, rx
+
+
+; Nothing (no special features).
+;
+; CHECK-LABEL: test_n:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwu 1, -[[SIZE:[0-9]+]](1)
+; CHECK: addi 1, 1, [[SIZE]]
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_n() local_unnamed_addr #0 {
+entry:
+ %t0 = tail call i32 bitcast (i32 (...)* @bar0 to i32 ()*)() #0
+ ret i32 %t0
+}
+
+; Aligned object on the stack.
+;
+; CHECK-LABEL: test_a:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+
+define i32 @test_a() local_unnamed_addr #0 {
+entry:
+ %t0 = alloca i32, align 128
+ %t1 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ ret i32 %t1
+}
+
+; Dynamic allocation on the stack.
+;
+; CHECK-LABEL: test_d:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwu 1, -[[SIZE:[0-9]+]](1)
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_d(i32 %p0) local_unnamed_addr #0 {
+ %t0 = alloca i32, i32 %p0, align 4
+ %t1 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ ret i32 %t1
+}
+
+; Large stack (exceeds size of D-field).
+; CHECK-LABEL: test_s:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_s(i32 %p0) local_unnamed_addr #0 {
+entry:
+ %t0 = alloca [16384 x i32]
+ %t1 = getelementptr [16384 x i32], [16384 x i32]* %t0, i32 0, i32 0
+ %t2 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t1) #0
+ ret i32 %t2
+}
+
+; Combinations.
+
+; CHECK-LABEL: test_ad:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_ad(i32 %p0) local_unnamed_addr #0 {
+ %t0 = alloca i32, align 128
+ %t1 = alloca i32, i32 %p0, align 4
+ %t2 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ %t3 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t1) #0
+ %t4 = add i32 %t2, %t3
+ ret i32 %t4
+}
+
+; CHECK-LABEL: test_as:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_as() local_unnamed_addr #0 {
+ %t0 = alloca i32, align 128
+ %t1 = alloca [16384 x i32]
+ %t2 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ %t3 = getelementptr [16384 x i32], [16384 x i32]* %t1, i32 0, i32 0
+ %t4 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t3) #0
+ %t5 = add i32 %t2, %t4
+ ret i32 %t5
+}
+
+; CHECK-LABEL: test_ds:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_ds(i32 %p0) local_unnamed_addr #0 {
+ %t0 = alloca i32, i32 %p0, align 4
+ %t1 = alloca [16384 x i32]
+ %t2 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ %t3 = getelementptr [16384 x i32], [16384 x i32]* %t1, i32 0, i32 0
+ %t4 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t3) #0
+ %t5 = add i32 %t2, %t4
+ ret i32 %t5
+}
+
+; CHECK-LABEL: test_ads:
+; CHECK-NOT: stw {{[0-9]+}}, -{{[0-9]+}}(1)
+; CHECK: stwux 1, 1, {{[0-9]+}}
+; CHECK: mr 1, {{[0-9]+}}
+; CHECK-NOT: lwz {{[0-9]+}}, -{{[0-9]+}}(1)
+define i32 @test_ads(i32 %p0) local_unnamed_addr #0 {
+ %t0 = alloca i32, align 128
+ %t1 = alloca i32, i32 %p0, align 4
+ %t2 = alloca [16384 x i32]
+
+ %t3 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t0) #0
+ %t4 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t1) #0
+ %t5 = add i32 %t3, %t4
+
+ %t6 = getelementptr [16384 x i32], [16384 x i32]* %t2, i32 0, i32 0
+ %t7 = tail call i32 bitcast (i32 (...)* @bar1 to i32 (i32*)*)(i32* %t6) #0
+ %t8 = add i32 %t5, %t7
+ ret i32 %t7
+}
+
+
+declare i32 @bar0(...) local_unnamed_addr #0
+declare i32 @bar1(...) local_unnamed_addr #0
+
+attributes #0 = { nounwind }
; CHECK-32-DAG: subfic 0, [[REG]], -64
; CHECK-32: stwux 1, 1, 0
; CHECK-32: subf 0, 0, 1
-; CHECK-32: stw 30, -8(0)
-; CHECK-32: mr 30, 0
+; CHECK-32: addic 0, 0, -4
+; CHECK-32: stwx 31, 0, 0
+; CHECK-32: addic 0, 0, -4
+; CHECK-32: stwx 30, 0, 0
+; CHECK-32: addic 30, 0, 8
; CHECK-32-PIC-LABEL: @goo
; CHECK-32-PIC-DAG: mflr [[LR:[0-9]+]]
; CHECK-32-PIC-DAG: clrlwi [[REG:[0-9]+]], 1, 27
; CHECK-32-PIC-DAG: stw [[LR]], 4(1)
; CHECK-32-PIC-DAG: subfic 0, [[REG]], -64
-; CHECK-32-PIC: stwux 1, 1, 0
-; CHECK-32-PIC: subf 0, 0, 1
-; CHECK-32-PIC: stw 29, -12(0)
-; CHECK-32-PIC-DAG: mr 29, 0
+; CHECK-32-PIC: stwux 1, 1, 0
+; CHECK-32-PIC: subf 0, 0, 1
+; CHECK-32-PIC: addic 0, 0, -4
+; CHECK-32-PIC: stwx 31, 0, 0
+; CHECK-32-PIC: addic 0, 0, -4
+; CHECK-32-PIC: stwx 30, 0, 0
+; CHECK-32-PIC: addic 0, 0, -4
+; CHECK-32-PIC: stwx 29, 0, 0
+; CHECK-32-PIC: addic 29, 0, 12
; The large-frame-size case.
define void @hoo(%struct.s* byval nocapture readonly %a) {
; CHECK-32-DAG: subfc 0, [[REG3]], [[REG2]]
; CHECK-32: stwux 1, 1, 0
; CHECK-32: subf 0, 0, 1
-; CHECK-32-DAG: stw 31, -4(0)
-; CHECK-32-DAG: stw 30, -8(0)
-; CHECK-32: mr 30, 0
+; CHECK-32: addic 0, 0, -4
+; CHECK-32: stwx 31, 0, 0
+; CHECK-32: addic 0, 0, -4
+; CHECK-32: stwx 30, 0, 0
+; CHECK-32: addic 30, 0, 8
; CHECK-32: blr
; CHECK-32-PIC-DAG: ori [[REG2:[0-9]+]], [[REG1]], 51904
; CHECK-32-PIC-DAG: stw 0, 4(1)
; CHECK-32-PIC-DAG: subfc 0, [[REG3]], [[REG2]]
-; CHECK-32-PIC: stwux 1, 1, 0
-; CHECK-32-PIC: stw 29, -12(0)
-; CHECK-32-PIC: subf 0, 0, 1
-; CHECK-32-PIC: mr 29, 0
+; CHECK-32-PIC: stwux 1, 1, 0
+; CHECK-32-PIC: subf 0, 0, 1
+; CHECK-32-PIC: addic 0, 0, -4
+; CHECK-32-PIC: stwx 31, 0, 0
+; CHECK-32-PIC: addic 0, 0, -8
+; CHECK-32-PIC: stwx 29, 0, 0
+; CHECK-32-PIC: addic 29, 0, 12
; CHECK-32: blr