FixupStatepointCallerSaved.cpp File Reference

Statepoint instruction in deopt parameters contains values which are meaningful to the runtime and should be able to be read at the moment the call returns. More...

#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/StackMaps.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Debug.h"

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "fixup-statepoint-caller-saved"

Functions
	STATISTIC (NumSpilledRegisters, "Number of spilled register")
	STATISTIC (NumSpillSlotsAllocated, "Number of spill slots allocated")
	STATISTIC (NumSpillSlotsExtended, "Number of spill slots extended")
	INITIALIZE_PASS_BEGIN (FixupStatepointCallerSaved, DEBUG_TYPE, "Fixup Statepoint Caller Saved", false, false) INITIALIZE_PASS_END(FixupStatepointCallerSaved
Fixup Statepoint Caller static false unsigned	getRegisterSize (const TargetRegisterInfo &TRI, Register Reg)
static Register	performCopyPropagation (Register Reg, MachineBasicBlock::iterator &RI, bool &IsKill, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI)

Variables
static cl::opt< bool >	FixupSCSExtendSlotSize ("fixup-scs-extend-slot-size", cl::Hidden, cl::init(false), cl::desc("Allow spill in spill slot of greater size than register size"), cl::Hidden)
static cl::opt< bool >	PassGCPtrInCSR ("fixup-allow-gcptr-in-csr", cl::Hidden, cl::init(false), cl::desc("Allow passing GC Pointer arguments in callee saved registers"))
static cl::opt< bool >	EnableCopyProp ("fixup-scs-enable-copy-propagation", cl::Hidden, cl::init(true), cl::desc("Enable simple copy propagation during register reloading"))
static cl::opt< unsigned >	MaxStatepointsWithRegs ("fixup-max-csr-statepoints", cl::Hidden, cl::desc("Max number of statepoints allowed to pass GC Ptrs in registers"))
	DEBUG_TYPE
Fixup Statepoint Caller	Saved
Fixup Statepoint Caller	false

Detailed Description

Statepoint instruction in deopt parameters contains values which are meaningful to the runtime and should be able to be read at the moment the call returns.

So we can say that we need to encode the fact that these values are "late read" by runtime. If we could express this notion for register allocator it would produce the right form for us. The need to fixup (i.e this pass) is specifically handling the fact that we cannot describe such a late read for the register allocator. Register allocator may put the value on a register clobbered by the call. This pass forces the spill of such registers and replaces corresponding statepoint operands to added spill slots.

Definition in file FixupStatepointCallerSaved.cpp.

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "fixup-statepoint-caller-saved"

Definition at line 35 of file FixupStatepointCallerSaved.cpp.

Function Documentation

getRegisterSize()

Fixup Statepoint Caller static false unsigned getRegisterSize ( const TargetRegisterInfo &  TRI, Register  Reg  )

static

Definition at line 92 of file FixupStatepointCallerSaved.cpp.

References TRI.

Referenced by performCopyPropagation().

INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	FixupStatepointCallerSaved	,
		DEBUG_TYPE	,
		"Fixup Statepoint Caller Saved"	,
		false	,
		false
	)

performCopyPropagation()

static Register performCopyPropagation ( Register  Reg, MachineBasicBlock::iterator &  RI, bool &  IsKill, const TargetInstrInfo &  TII, const TargetRegisterInfo &  TRI  )

static

Definition at line 110 of file FixupStatepointCallerSaved.cpp.

References llvm::dbgs(), EnableCopyProp, getRegisterSize(), llvm::MachineInstrBundleIterator< Ty, IsReverse >::getReverse(), Idx, LLVM_DEBUG, MBB, llvm::printReg(), llvm::MachineBasicBlock::rend(), TII, and TRI.

STATISTIC() [1/3]

STATISTIC	(	NumSpilledRegisters	,
		"Number of spilled register"
	)

STATISTIC() [2/3]

STATISTIC	(	NumSpillSlotsAllocated	,
		"Number of spill slots allocated"
	)

STATISTIC() [3/3]

STATISTIC	(	NumSpillSlotsExtended	,
		"Number of spill slots extended"
	)

Variable Documentation

DEBUG_TYPE

DEBUG_TYPE

Definition at line 88 of file FixupStatepointCallerSaved.cpp.

EnableCopyProp

cl::opt< bool > EnableCopyProp("fixup-scs-enable-copy-propagation", cl::Hidden, cl::init(true), cl::desc("Enable simple copy propagation during register reloading")) ( "fixup-scs-enable-copy-propagation"  , cl::Hidden  , cl::init(true)  , cl::desc("Enable simple copy propagation during register reloading")    )

static

Referenced by performCopyPropagation().

false

Fixup Statepoint Caller false

Definition at line 89 of file FixupStatepointCallerSaved.cpp.

FixupSCSExtendSlotSize

cl::opt< bool > FixupSCSExtendSlotSize("fixup-scs-extend-slot-size", cl::Hidden, cl::init(false), cl::desc("Allow spill in spill slot of greater size than register size"), cl::Hidden) ( "fixup-scs-extend-slot-size"  , cl::Hidden  , cl::init(false)  , cl::desc("Allow spill in spill slot of greater size than register size")  , cl::Hidden    )

static

MaxStatepointsWithRegs

cl::opt< unsigned > MaxStatepointsWithRegs("fixup-max-csr-statepoints", cl::Hidden, cl::desc("Max number of statepoints allowed to pass GC Ptrs in registers")) ( "fixup-max-csr-statepoints"  , cl::Hidden  , cl::desc("Max number of statepoints allowed to pass GC Ptrs in registers")    )

static

PassGCPtrInCSR

cl::opt< bool > PassGCPtrInCSR("fixup-allow-gcptr-in-csr", cl::Hidden, cl::init(false), cl::desc("Allow passing GC Pointer arguments in callee saved registers")) ( "fixup-allow-gcptr-in-csr"  , cl::Hidden  , cl::init(false)  , cl::desc("Allow passing GC Pointer arguments in callee saved registers")    )

static

Saved

Fixup Statepoint Caller Saved

Definition at line 89 of file FixupStatepointCallerSaved.cpp.

Referenced by llvm::X86::optimizeMOV(), and optimizeToFixedRegisterForm().