1 //===-- ARMInstrInfo.cpp - ARM Instruction Information --------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the ARM implementation of the TargetInstrInfo class.
12 //===----------------------------------------------------------------------===//
14 #include "ARMInstrInfo.h"
16 #include "ARMConstantPoolValue.h"
17 #include "ARMMachineFunctionInfo.h"
18 #include "ARMTargetMachine.h"
19 #include "MCTargetDesc/ARMAddressingModes.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/CodeGen/LiveVariables.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineInstrBuilder.h"
24 #include "llvm/CodeGen/MachineJumpTableInfo.h"
25 #include "llvm/CodeGen/MachineRegisterInfo.h"
26 #include "llvm/IR/Function.h"
27 #include "llvm/IR/GlobalVariable.h"
28 #include "llvm/MC/MCAsmInfo.h"
29 #include "llvm/MC/MCInst.h"
32 ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
33 : ARMBaseInstrInfo(STI), RI(STI) {
36 /// getNoopForMachoTarget - Return the noop instruction to use for a noop.
37 void ARMInstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
39 NopInst.setOpcode(ARM::HINT);
40 NopInst.addOperand(MCOperand::CreateImm(0));
41 NopInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
42 NopInst.addOperand(MCOperand::CreateReg(0));
44 NopInst.setOpcode(ARM::MOVr);
45 NopInst.addOperand(MCOperand::CreateReg(ARM::R0));
46 NopInst.addOperand(MCOperand::CreateReg(ARM::R0));
47 NopInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
48 NopInst.addOperand(MCOperand::CreateReg(0));
49 NopInst.addOperand(MCOperand::CreateReg(0));
53 unsigned ARMInstrInfo::getUnindexedOpcode(unsigned Opc) const {
56 case ARM::LDR_PRE_IMM:
57 case ARM::LDR_PRE_REG:
58 case ARM::LDR_POST_IMM:
59 case ARM::LDR_POST_REG:
64 case ARM::LDRB_PRE_IMM:
65 case ARM::LDRB_PRE_REG:
66 case ARM::LDRB_POST_IMM:
67 case ARM::LDRB_POST_REG:
75 case ARM::STR_PRE_IMM:
76 case ARM::STR_PRE_REG:
77 case ARM::STR_POST_IMM:
78 case ARM::STR_POST_REG:
83 case ARM::STRB_PRE_IMM:
84 case ARM::STRB_PRE_REG:
85 case ARM::STRB_POST_IMM:
86 case ARM::STRB_POST_REG:
93 void ARMInstrInfo::expandLoadStackGuard(MachineBasicBlock::iterator MI,
94 Reloc::Model RM) const {
95 if (RM == Reloc::PIC_)
96 expandLoadStackGuardBase(MI, ARM::LDRLIT_ga_pcrel, ARM::LDRi12, RM);
98 expandLoadStackGuardBase(MI, ARM::LDRLIT_ga_abs, ARM::LDRi12, RM);
102 /// ARMCGBR - Create Global Base Reg pass. This initializes the PIC
103 /// global base register for ARM ELF.
104 struct ARMCGBR : public MachineFunctionPass {
106 ARMCGBR() : MachineFunctionPass(ID) {}
108 bool runOnMachineFunction(MachineFunction &MF) override {
109 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
110 if (AFI->getGlobalBaseReg() == 0)
113 const ARMTargetMachine *TM =
114 static_cast<const ARMTargetMachine *>(&MF.getTarget());
115 if (TM->getRelocationModel() != Reloc::PIC_)
118 LLVMContext *Context = &MF.getFunction()->getContext();
119 unsigned ARMPCLabelIndex = AFI->createPICLabelUId();
120 unsigned PCAdj = TM->getSubtarget<ARMSubtarget>().isThumb() ? 4 : 8;
121 ARMConstantPoolValue *CPV = ARMConstantPoolSymbol::Create(
122 *Context, "_GLOBAL_OFFSET_TABLE_", ARMPCLabelIndex, PCAdj);
125 TM->getSubtargetImpl()->getDataLayout()->getPrefTypeAlignment(
126 Type::getInt32PtrTy(*Context));
127 unsigned Idx = MF.getConstantPool()->getConstantPoolIndex(CPV, Align);
129 MachineBasicBlock &FirstMBB = MF.front();
130 MachineBasicBlock::iterator MBBI = FirstMBB.begin();
131 DebugLoc DL = FirstMBB.findDebugLoc(MBBI);
133 MF.getRegInfo().createVirtualRegister(&ARM::rGPRRegClass);
134 unsigned Opc = TM->getSubtarget<ARMSubtarget>().isThumb2() ?
135 ARM::t2LDRpci : ARM::LDRcp;
136 const TargetInstrInfo &TII = *TM->getSubtargetImpl()->getInstrInfo();
137 MachineInstrBuilder MIB = BuildMI(FirstMBB, MBBI, DL,
138 TII.get(Opc), TempReg)
139 .addConstantPoolIndex(Idx);
140 if (Opc == ARM::LDRcp)
144 // Fix the GOT address by adding pc.
145 unsigned GlobalBaseReg = AFI->getGlobalBaseReg();
146 Opc = TM->getSubtarget<ARMSubtarget>().isThumb2() ? ARM::tPICADD
148 MIB = BuildMI(FirstMBB, MBBI, DL, TII.get(Opc), GlobalBaseReg)
150 .addImm(ARMPCLabelIndex);
151 if (Opc == ARM::PICADD)
158 const char *getPassName() const override {
159 return "ARM PIC Global Base Reg Initialization";
162 void getAnalysisUsage(AnalysisUsage &AU) const override {
163 AU.setPreservesCFG();
164 MachineFunctionPass::getAnalysisUsage(AU);
169 char ARMCGBR::ID = 0;
171 llvm::createARMGlobalBaseRegPass() { return new ARMCGBR(); }