llvm-6502/lib/Target/ARM/Thumb2InstrInfo.h
Akira Hatanaka 0651a556fe [stack protector] Fix a potential security bug in stack protector where the
address of the stack guard was being spilled to the stack.

Previously the address of the stack guard would get spilled to the stack if it
was impossible to keep it in a register. This patch introduces a new target
independent node and pseudo instruction which gets expanded post-RA to a
sequence of instructions that load the stack guard value. Register allocator
can now just remat the value when it can't keep it in a register. 

<rdar://problem/12475629>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213967 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 19:31:34 +00:00

79 lines
3.0 KiB
C++

//===-- Thumb2InstrInfo.h - Thumb-2 Instruction Information -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the Thumb-2 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#ifndef THUMB2INSTRUCTIONINFO_H
#define THUMB2INSTRUCTIONINFO_H
#include "ARMBaseInstrInfo.h"
#include "Thumb2RegisterInfo.h"
namespace llvm {
class ARMSubtarget;
class ScheduleHazardRecognizer;
class Thumb2InstrInfo : public ARMBaseInstrInfo {
Thumb2RegisterInfo RI;
public:
explicit Thumb2InstrInfo(const ARMSubtarget &STI);
/// getNoopForMachoTarget - Return the noop instruction to use for a noop.
void getNoopForMachoTarget(MCInst &NopInst) const override;
// Return the non-pre/post incrementing version of 'Opc'. Return 0
// if there is not such an opcode.
unsigned getUnindexedOpcode(unsigned Opc) const override;
void ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
MachineBasicBlock *NewDest) const override;
bool isLegalToSplitMBBAt(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI) const override;
void copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I, DebugLoc DL,
unsigned DestReg, unsigned SrcReg,
bool KillSrc) const override;
void storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI,
unsigned SrcReg, bool isKill, int FrameIndex,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const override;
void loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI,
unsigned DestReg, int FrameIndex,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const override;
/// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As
/// such, whenever a client has an instance of instruction info, it should
/// always be able to get register info as well (through this method).
///
const Thumb2RegisterInfo &getRegisterInfo() const override { return RI; }
private:
void expandLoadStackGuard(MachineBasicBlock::iterator MI,
Reloc::Model RM) const override;
};
/// getITInstrPredicate - Valid only in Thumb2 mode. This function is identical
/// to llvm::getInstrPredicate except it returns AL for conditional branch
/// instructions which are "predicated", but are not in IT blocks.
ARMCC::CondCodes getITInstrPredicate(const MachineInstr *MI, unsigned &PredReg);
}
#endif // THUMB2INSTRUCTIONINFO_H