llvm-6502/lib/Target/ARM/ARMInstrInfo.cpp
Jim Grosbach c01810eeb7 ARM implement TargetInstrInfo::getNoopForMachoTarget()
Without this hook, functions w/ a completely empty body (including no
epilogue) will cause an MCEmitter assertion failure.

For example,
define internal fastcc void @empty_function() {
  unreachable
}

rdar://10947471

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151673 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-28 23:53:30 +00:00

86 lines
2.5 KiB
C++

//===-- ARMInstrInfo.cpp - ARM Instruction Information --------------------===//
//
// 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 ARM implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "ARMInstrInfo.h"
#include "ARM.h"
#include "ARMMachineFunctionInfo.h"
#include "MCTargetDesc/ARMAddressingModes.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/LiveVariables.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCInst.h"
using namespace llvm;
ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
: ARMBaseInstrInfo(STI), RI(*this, STI) {
}
/// getNoopForMachoTarget - Return the noop instruction to use for a noop.
void ARMInstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
if (hasNOP()) {
NopInst.setOpcode(ARM::NOP);
NopInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
NopInst.addOperand(MCOperand::CreateReg(0));
} else {
NopInst.setOpcode(ARM::MOVr);
NopInst.addOperand(MCOperand::CreateReg(ARM::R0));
NopInst.addOperand(MCOperand::CreateReg(ARM::R0));
NopInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
NopInst.addOperand(MCOperand::CreateReg(0));
NopInst.addOperand(MCOperand::CreateReg(0));
}
}
unsigned ARMInstrInfo::getUnindexedOpcode(unsigned Opc) const {
switch (Opc) {
default: break;
case ARM::LDR_PRE_IMM:
case ARM::LDR_PRE_REG:
case ARM::LDR_POST_IMM:
case ARM::LDR_POST_REG:
return ARM::LDRi12;
case ARM::LDRH_PRE:
case ARM::LDRH_POST:
return ARM::LDRH;
case ARM::LDRB_PRE_IMM:
case ARM::LDRB_PRE_REG:
case ARM::LDRB_POST_IMM:
case ARM::LDRB_POST_REG:
return ARM::LDRBi12;
case ARM::LDRSH_PRE:
case ARM::LDRSH_POST:
return ARM::LDRSH;
case ARM::LDRSB_PRE:
case ARM::LDRSB_POST:
return ARM::LDRSB;
case ARM::STR_PRE_IMM:
case ARM::STR_PRE_REG:
case ARM::STR_POST_IMM:
case ARM::STR_POST_REG:
return ARM::STRi12;
case ARM::STRH_PRE:
case ARM::STRH_POST:
return ARM::STRH;
case ARM::STRB_PRE_IMM:
case ARM::STRB_PRE_REG:
case ARM::STRB_POST_IMM:
case ARM::STRB_POST_REG:
return ARM::STRBi12;
}
return 0;
}