Differential D88701 Diff 295996 llvm/lib/Target/AArch64/AArch64FrameLowering.cpp

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llvm/lib/Target/AArch64/AArch64FrameLowering.cpp

Show First 20 Lines • Show All 573 Lines • ▼ Show 20 Lines	static bool windowsRequiresStackProbe(MachineFunction &MF,
if (F.hasFnAttribute("stack-probe-size"))		if (F.hasFnAttribute("stack-probe-size"))
F.getFnAttribute("stack-probe-size")		F.getFnAttribute("stack-probe-size")
.getValueAsString()		.getValueAsString()
.getAsInteger(0, StackProbeSize);		.getAsInteger(0, StackProbeSize);
return (StackSizeInBytes >= StackProbeSize) &&		return (StackSizeInBytes >= StackProbeSize) &&
!F.hasFnAttribute("no-stack-arg-probe");		!F.hasFnAttribute("no-stack-arg-probe");
}		}

		static bool needsWinCFI(const MachineFunction &MF) {
		const Function &F = MF.getFunction();
		return MF.getTarget().getMCAsmInfo()->usesWindowsCFI() &&
		F.needsUnwindTableEntry();
		}

bool AArch64FrameLowering::shouldCombineCSRLocalStackBump(		bool AArch64FrameLowering::shouldCombineCSRLocalStackBump(
MachineFunction &MF, uint64_t StackBumpBytes) const {		MachineFunction &MF, uint64_t StackBumpBytes) const {
AArch64FunctionInfo *AFI = MF.getInfo<AArch64FunctionInfo>();		AArch64FunctionInfo *AFI = MF.getInfo<AArch64FunctionInfo>();
const MachineFrameInfo &MFI = MF.getFrameInfo();		const MachineFrameInfo &MFI = MF.getFrameInfo();
const AArch64Subtarget &Subtarget = MF.getSubtarget<AArch64Subtarget>();		const AArch64Subtarget &Subtarget = MF.getSubtarget<AArch64Subtarget>();
const AArch64RegisterInfo *RegInfo = Subtarget.getRegisterInfo();		const AArch64RegisterInfo *RegInfo = Subtarget.getRegisterInfo();

if (AFI->getLocalStackSize() == 0)		if (AFI->getLocalStackSize() == 0)
return false;		return false;

		// For WinCFI, if optimizing for size, prefer to not combine the stack bump
		// (to force a stp with predecrement) to match the packed unwind format,
		// provided that there actually are any callee saved registers to merge the
		// decrement with.
		// This is potentially marginally slower, but allows using the packed
		// unwind format for functions that both have a local area and callee saved
		// registers. Using the packed unwind format notably reduces the size of
		// the unwind info.
		if (needsWinCFI(MF) && AFI->getCalleeSavedStackSize() > 0 &&
		MF.getFunction().hasOptSize())
		return false;

// 512 is the maximum immediate for stp/ldp that will be used for		// 512 is the maximum immediate for stp/ldp that will be used for
// callee-save save/restores		// callee-save save/restores
if (StackBumpBytes >= 512 \|\| windowsRequiresStackProbe(MF, StackBumpBytes))		if (StackBumpBytes >= 512 \|\| windowsRequiresStackProbe(MF, StackBumpBytes))
return false;		return false;

if (MFI.hasVarSizedObjects())		if (MFI.hasVarSizedObjects())
return false;		return false;

▲ Show 20 Lines • Show All 377 Lines • ▼ Show 20 Lines	static void adaptForLdStOpt(MachineBasicBlock &MBB,
// add sp, sp, #64		// add sp, sp, #64
//		//
// and the load-store optimizer can merge the last two instructions into:		// and the load-store optimizer can merge the last two instructions into:
//		//
// ldp x26, x25, [sp], #64		// ldp x26, x25, [sp], #64
//		//
}		}

static bool needsWinCFI(const MachineFunction &MF) {
const Function &F = MF.getFunction();
return MF.getTarget().getMCAsmInfo()->usesWindowsCFI() &&
F.needsUnwindTableEntry();
}

static bool isTargetWindows(const MachineFunction &MF) {		static bool isTargetWindows(const MachineFunction &MF) {
return MF.getSubtarget<AArch64Subtarget>().isTargetWindows();		return MF.getSubtarget<AArch64Subtarget>().isTargetWindows();
}		}

// Convenience function to determine whether I is an SVE callee save.		// Convenience function to determine whether I is an SVE callee save.
static bool IsSVECalleeSave(MachineBasicBlock::iterator I) {		static bool IsSVECalleeSave(MachineBasicBlock::iterator I) {
switch (I->getOpcode()) {		switch (I->getOpcode()) {
default:		default:
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