AArch64FrameLowering.cpp File Reference

#include "AArch64FrameLowering.h"
#include "AArch64InstrInfo.h"
#include "AArch64MachineFunctionInfo.h"
#include "AArch64PrologueEpilogue.h"
#include "AArch64RegisterInfo.h"
#include "AArch64SMEAttributes.h"
#include "AArch64Subtarget.h"
#include "MCTargetDesc/AArch64AddressingModes.h"
#include "MCTargetDesc/AArch64MCTargetDesc.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/CodeGen/CFIInstBuilder.h"
#include "llvm/CodeGen/LivePhysRegs.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/CodeGen/WinEHFuncInfo.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
#include <cassert>
#include <cstdint>
#include <iterator>
#include <optional>
#include <vector>

Go to the source code of this file.

Classes
struct	StackAccess

Macros
#define	DEBUG_TYPE   "frame-info"
#define	CASE(n)
#define	CASE(n)

Enumerations
enum class	AssignObjectOffsets { No , Yes }

Functions
static bool	produceCompactUnwindFrame (const AArch64FrameLowering &, MachineFunction &MF)
static SVEStackSizes	determineSVEStackSizes (MachineFunction &MF, AssignObjectOffsets AssignOffsets)
	Process all the SVE stack objects and the SVE stack size and offsets for each object.
static unsigned	getStackHazardSize (const MachineFunction &MF)
static bool	isLikelyToHaveSVEStack (const AArch64FrameLowering &AFL, const MachineFunction &MF)
static bool	isTargetWindows (const MachineFunction &MF)
static unsigned	estimateRSStackSizeLimit (MachineFunction &MF)
	Look at each instruction that references stack frames and return the stack size limit beyond which some of these instructions will require a scratch register during their expansion later.
static MCRegister	getRegisterOrZero (MCRegister Reg, bool HasSVE)
static void	getLiveRegsForEntryMBB (LivePhysRegs &LiveRegs, const MachineBasicBlock &MBB)
static RegState	getPrologueDeath (MachineFunction &MF, unsigned Reg)
static bool	invalidateWindowsRegisterPairing (bool SpillExtendedVolatile, unsigned SpillCount, unsigned Reg1, unsigned Reg2, bool NeedsWinCFI, const TargetRegisterInfo *TRI)
static bool	invalidateRegisterPairing (bool SpillExtendedVolatile, unsigned SpillCount, unsigned Reg1, unsigned Reg2, bool UsesWinAAPCS, bool NeedsWinCFI, bool NeedsFrameRecord, const TargetRegisterInfo *TRI)
	Returns true if Reg1 and Reg2 cannot be paired using a ldp/stp instruction.
static bool	isValidMemOpOffset (const AArch64InstrInfo *TII, unsigned Opcode, int Offset)
MCRegister	findFreePredicateReg (BitVector &SavedRegs)
bool	enableMultiVectorSpillFill (const AArch64Subtarget &Subtarget, MachineFunction &MF)
void	computeCalleeSaveRegisterPairs (const AArch64FrameLowering &AFL, MachineFunction &MF, ArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI, SmallVectorImpl< RegPairInfo > &RegPairs, bool NeedsFrameRecord)
static std::optional< int >	getMMOFrameID (MachineMemOperand *MMO, const MachineFrameInfo &MFI)
static std::optional< int >	getLdStFrameID (const MachineInstr &MI, const MachineFrameInfo &MFI)
static bool	isPPRAccess (const MachineInstr &MI)
static void	orderZPRCalleeSavesForPairs (MachineFunction &MF, const TargetRegisterInfo *RegInfo, std::vector< CalleeSavedInfo > &CSI)
static bool	getSVECalleeSaveSlotRange (const MachineFrameInfo &MFI, int &Min, int &Max)
	returns true if there are any SVE callee saves.
static raw_ostream &	operator<< (raw_ostream &OS, const StackAccess &SA)

Variables
static const unsigned	DefaultSafeSPDisplacement = 255
	This is the biggest offset to the stack pointer we can encode in aarch64 instructions (without using a separate calculation and a temp register).

Macro Definition Documentation

CASE [1/2]

#define CASE

(

n

)

Value:

  case AArch64::W##n:                                                          \
  case AArch64::X##n:                                                          \
    return AArch64::X##n

CASE [2/2]

#define CASE

(

n

)

Value:

  case AArch64::B##n:                                                          \
  case AArch64::H##n:                                                          \
  case AArch64::S##n:                                                          \
  case AArch64::D##n:                                                          \
  case AArch64::Q##n:                                                          \
    return HasSVE ? AArch64::Z##n : AArch64::Q##n

DEBUG_TYPE

#define DEBUG_TYPE   "frame-info"

Definition at line 266 of file AArch64FrameLowering.cpp.

Enumeration Type Documentation

AssignObjectOffsets

enum class AssignObjectOffsets

strong

Enumerator
No
Yes

Definition at line 299 of file AArch64FrameLowering.cpp.

Function Documentation

computeCalleeSaveRegisterPairs()

void computeCalleeSaveRegisterPairs	(	const AArch64FrameLowering &	AFL,
		MachineFunction &	MF,
		ArrayRef< CalleeSavedInfo >	CSI,
		const TargetRegisterInfo *	TRI,
		SmallVectorImpl< RegPairInfo > &	RegPairs,
		bool	NeedsFrameRecord )

Definition at line 1674 of file AArch64FrameLowering.cpp.

References llvm::alignDown(), llvm::Aligned, llvm::alignTo(), llvm::any_of(), assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), contains(), llvm::Count, llvm::CallingConv::CXX_FAST_TLS, llvm::ArrayRef< T >::empty(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::AArch64FunctionInfo::getCalleeSavedStackSize(), llvm::Function::getCallingConv(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectAlign(), llvm::AArch64FunctionInfo::getPPRCalleeSavedStackSize(), llvm::AArch64FunctionInfo::getPredicateRegForFillSpill(), getStackHazardSize(), llvm::MachineFunction::getSubtarget(), llvm::AArch64FunctionInfo::getZPRCalleeSavedStackSize(), llvm::AArch64FunctionInfo::hasCalleeSaveStackFreeSpace(), llvm::AArch64FunctionInfo::hasSplitSVEObjects(), llvm::AArch64FunctionInfo::hasStackHazardSlotIndex(), llvm::AArch64FrameLowering::hasSVECalleeSavesAboveFrameRecord(), llvm::AArch64FunctionInfo::hasSwiftAsyncContext(), invalidateRegisterPairing(), llvm::AArch64InstrInfo::isFpOrNEON(), isTargetWindows(), isValidMemOpOffset(), llvm_unreachable, llvm::AArch64FrameLowering::needsWinCFI(), llvm::Offset, llvm::CallingConv::PreserveAll, llvm::CallingConv::PreserveMost, produceCompactUnwindFrame(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), Reg, llvm::AArch64FunctionInfo::setCalleeSaveBaseToFrameRecordOffset(), llvm::MachineFrameInfo::setObjectAlignment(), llvm::ArrayRef< T >::size(), TII, TRI, and llvm::CallingConv::Win64.

Referenced by llvm::AArch64FrameLowering::restoreCalleeSavedRegisters(), and llvm::AArch64FrameLowering::spillCalleeSavedRegisters().

determineSVEStackSizes()

SVEStackSizes determineSVEStackSizes ( MachineFunction & MF, AssignObjectOffsets AssignOffsets )

static

Process all the SVE stack objects and the SVE stack size and offsets for each object.

If AssignOffsets is "Yes", the offsets get assigned (and SVE stack sizes set). Returns the size of the SVE stack.

Definition at line 3018 of file AArch64FrameLowering.cpp.

References llvm::alignTo(), assert(), llvm::dbgs(), E(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectAlign(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::MachineFrameInfo::getObjectSize(), llvm::MachineFrameInfo::getStackID(), llvm::MachineFrameInfo::getStackProtectorIndex(), getSVECalleeSaveSlotRange(), llvm::MachineFrameInfo::hasScalableStackID(), llvm::AArch64FunctionInfo::hasSplitSVEObjects(), llvm::MachineFrameInfo::hasStackProtectorIndex(), I, llvm::MachineFrameInfo::isCalleeSavedObjectIndex(), llvm::MachineFrameInfo::isDeadObjectIndex(), LLVM_DEBUG, llvm::Offset, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::report_fatal_error(), llvm::TargetStackID::ScalablePredicateVector, llvm::TargetStackID::ScalableVector, llvm::MachineFrameInfo::setObjectOffset(), llvm::AArch64FunctionInfo::setStackSizeSVE(), uint64_t, and Yes.

Referenced by llvm::AArch64FrameLowering::determineCalleeSaves(), and llvm::AArch64FrameLowering::processFunctionBeforeFrameFinalized().

enableMultiVectorSpillFill()

bool enableMultiVectorSpillFill	(	const AArch64Subtarget &	Subtarget,
		MachineFunction &	MF )

Definition at line 1657 of file AArch64FrameLowering.cpp.

References llvm::AArch64Subtarget::getCLOpts(), llvm::MachineFunction::getInfo(), llvm::SMEAttrs::hasStreamingBody(), llvm::SMEAttrs::hasStreamingInterface(), and llvm::AArch64Subtarget::isStreaming().

Referenced by llvm::AArch64FrameLowering::assignCalleeSavedSpillSlots(), llvm::AArch64FrameLowering::determineCalleeSaves(), llvm::AArch64FrameLowering::restoreCalleeSavedRegisters(), and llvm::AArch64FrameLowering::spillCalleeSavedRegisters().

estimateRSStackSizeLimit()

unsigned estimateRSStackSizeLimit ( MachineFunction & MF )

static

Look at each instruction that references stack frames and return the stack size limit beyond which some of these instructions will require a scratch register during their expansion later.

Definition at line 431 of file AArch64FrameLowering.cpp.

References llvm::AArch64FrameOffsetCannotUpdate, DefaultSafeSPDisplacement, llvm::isAArch64FrameOffsetLegal(), MBB, MI, and llvm::Offset.

Referenced by llvm::AArch64FrameLowering::determineCalleeSaves(), llvm::ARMFrameLowering::determineCalleeSaves(), and llvm::CSKYFrameLowering::determineCalleeSaves().

findFreePredicateReg()

MCRegister findFreePredicateReg

(

BitVector &

SavedRegs

)

Definition at line 1646 of file AArch64FrameLowering.cpp.

References llvm::BitVector::test().

Referenced by llvm::AArch64FrameLowering::determineCalleeSaves().

getLdStFrameID()

std::optional< int > getLdStFrameID ( const MachineInstr & MI, const MachineFrameInfo & MFI )

static

Definition at line 2361 of file AArch64FrameLowering.cpp.

References getMMOFrameID(), and MI.

Referenced by llvm::AArch64FrameLowering::orderFrameObjects().

getLiveRegsForEntryMBB()

void getLiveRegsForEntryMBB ( LivePhysRegs & LiveRegs, const MachineBasicBlock & MBB )

static

Definition at line 874 of file AArch64FrameLowering.cpp.

References llvm::MachineRegisterInfo::getCalleeSavedRegs(), llvm::MachineFunction::getRegInfo(), and MBB.

Referenced by llvm::AArch64FrameLowering::canUseAsPrologue(), and llvm::RISCVFrameLowering::findScratchNonCalleeSaveRegister().

getMMOFrameID()

std::optional< int > getMMOFrameID ( MachineMemOperand * MMO, const MachineFrameInfo & MFI )

static

Definition at line 2341 of file AArch64FrameLowering.cpp.

References llvm::dyn_cast(), llvm::dyn_cast_or_null(), llvm::MachineFrameInfo::getObjectAllocation(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::MachineMemOperand::getPseudoValue(), llvm::getUnderlyingObject(), and llvm::MachineMemOperand::getValue().

Referenced by getLdStFrameID().

getPrologueDeath()

RegState getPrologueDeath ( MachineFunction & MF, unsigned Reg )

static

Definition at line 1533 of file AArch64FrameLowering.cpp.

References llvm::getKillRegState(), llvm::MachineFunction::getRegInfo(), llvm::MachineRegisterInfo::isLiveIn(), and Reg.

Referenced by llvm::AArch64FrameLowering::spillCalleeSavedRegisters().

getRegisterOrZero()

MCRegister getRegisterOrZero ( MCRegister Reg, bool HasSVE )

static

Definition at line 732 of file AArch64FrameLowering.cpp.

References CASE, and Reg.

getStackHazardSize()

unsigned getStackHazardSize ( const MachineFunction & MF )

static

Definition at line 306 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getSubtarget().

Referenced by llvm::AArch64FrameLowering::assignCalleeSavedSpillSlots(), computeCalleeSaveRegisterPairs(), llvm::AArch64FrameLowering::determineCalleeSaves(), and llvm::AArch64FrameLowering::getPPRStackSize().

getSVECalleeSaveSlotRange()

bool getSVECalleeSaveSlotRange ( const MachineFrameInfo & MFI, int & Min, int & Max )

static

returns true if there are any SVE callee saves.

Definition at line 2996 of file AArch64FrameLowering.cpp.

References assert(), contains(), llvm::MachineFrameInfo::getCalleeSavedInfo(), and llvm::MachineFrameInfo::isCalleeSavedInfoValid().

Referenced by determineSVEStackSizes().

invalidateRegisterPairing()

bool invalidateRegisterPairing ( bool SpillExtendedVolatile, unsigned SpillCount, unsigned Reg1, unsigned Reg2, bool UsesWinAAPCS, bool NeedsWinCFI, bool NeedsFrameRecord, const TargetRegisterInfo * TRI )

static

Returns true if Reg1 and Reg2 cannot be paired using a ldp/stp instruction.

WindowsCFI requires that only consecutive registers can be paired. LR and FP need to be allocated together when the frame needs to save the frame-record. This means any other register pairing with LR is invalid.

Definition at line 1594 of file AArch64FrameLowering.cpp.

References invalidateWindowsRegisterPairing(), and TRI.

Referenced by computeCalleeSaveRegisterPairs().

invalidateWindowsRegisterPairing()

bool invalidateWindowsRegisterPairing ( bool SpillExtendedVolatile, unsigned SpillCount, unsigned Reg1, unsigned Reg2, bool NeedsWinCFI, const TargetRegisterInfo * TRI )

static

Definition at line 1555 of file AArch64FrameLowering.cpp.

References TRI.

Referenced by invalidateRegisterPairing().

isLikelyToHaveSVEStack()

bool isLikelyToHaveSVEStack ( const AArch64FrameLowering & AFL, const MachineFunction & MF )

static

Definition at line 330 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::AArch64FrameLowering::getSVEStackSize(), and llvm::MachineFrameInfo::hasScalableStackID().

isPPRAccess()

bool isPPRAccess ( const MachineInstr & MI )

static

Definition at line 2370 of file AArch64FrameLowering.cpp.

References MI.

isTargetWindows()

bool isTargetWindows ( const MachineFunction & MF )

static

Definition at line 348 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getSubtarget(), and isTargetWindows().

Referenced by llvm::AArch64FrameLowering::assignCalleeSavedSpillSlots(), computeCalleeSaveRegisterPairs(), llvm::AArch64RegisterInfo::getCalleeSavedRegs(), llvm::AArch64FrameLowering::hasSVECalleeSavesAboveFrameRecord(), isTargetWindows(), orderZPRCalleeSavesForPairs(), llvm::AArch64FrameLowering::restoreCalleeSavedRegisters(), and llvm::AArch64FrameLowering::spillCalleeSavedRegisters().

isValidMemOpOffset()

bool isValidMemOpOffset ( const AArch64InstrInfo * TII, unsigned Opcode, int Offset )

static

Definition at line 1613 of file AArch64FrameLowering.cpp.

References llvm::Offset, and TII.

Referenced by computeCalleeSaveRegisterPairs().

operator<<()

raw_ostream & operator<< ( raw_ostream & OS, const StackAccess & SA )

inlinestatic

Definition at line 4127 of file AArch64FrameLowering.cpp.

References StackAccess::print().

orderZPRCalleeSavesForPairs()

void orderZPRCalleeSavesForPairs ( MachineFunction & MF, const TargetRegisterInfo * RegInfo, std::vector< CalleeSavedInfo > & CSI )

static

Definition at line 2806 of file AArch64FrameLowering.cpp.

References A(), llvm::append_range(), assert(), B(), contains(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::enumerate(), llvm::MachineFunction::getInfo(), llvm::AArch64FunctionInfo::getPPRCalleeSavedStackSize(), llvm::AArch64FunctionInfo::getPredicateRegForFillSpill(), llvm::AArch64FunctionInfo::getZPRCalleeSavedStackSize(), llvm::AArch64FunctionInfo::hasSplitSVEObjects(), isTargetWindows(), llvm::SmallVectorImpl< T >::pop_back_val(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorTemplateCommon< T, typename >::size(), llvm::sort(), and llvm::zip().

Referenced by llvm::AArch64FrameLowering::assignCalleeSavedSpillSlots().

produceCompactUnwindFrame()

bool produceCompactUnwindFrame ( const AArch64FrameLowering & AFL, MachineFunction & MF )

static

Definition at line 1543 of file AArch64FrameLowering.cpp.

References llvm::Function::getAttributes(), llvm::Function::getCallingConv(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getSubtarget(), llvm::AArch64Subtarget::getTargetLowering(), llvm::AArch64FunctionInfo::isSVECC(), llvm::AArch64Subtarget::isTargetMachO(), llvm::AArch64FrameLowering::requiresSaveVG(), and llvm::CallingConv::SwiftTail.

Referenced by computeCalleeSaveRegisterPairs(), and llvm::AArch64FrameLowering::determineCalleeSaves().

Variable Documentation

DefaultSafeSPDisplacement

const unsigned DefaultSafeSPDisplacement = 255

static

This is the biggest offset to the stack pointer we can encode in aarch64 instructions (without using a separate calculation and a temp register).

Note that the exception here are vector stores/loads which cannot encode any displacements (see estimateRSStackSizeLimit(), isAArch64FrameOffsetLegal()).

Definition at line 426 of file AArch64FrameLowering.cpp.

Referenced by estimateRSStackSizeLimit(), and llvm::AArch64FrameLowering::hasFPImpl().