llvm-6502/lib/Target/ARM/ARMMCCodeEmitter.cpp
Owen Anderson fe7fac74b4 Use the new IsAligned fixup flag to improve fixup encodings for Thumb2 branches. This is still not perfect,
but it gets many more of them correct than it did previously.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121414 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-09 21:34:47 +00:00

1122 lines
40 KiB
C++

//===-- ARM/ARMMCCodeEmitter.cpp - Convert ARM code to machine code -------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ARMMCCodeEmitter class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "mccodeemitter"
#include "ARM.h"
#include "ARMAddressingModes.h"
#include "ARMFixupKinds.h"
#include "ARMInstrInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
STATISTIC(MCNumCPRelocations, "Number of constant pool relocations created.");
namespace {
class ARMMCCodeEmitter : public MCCodeEmitter {
ARMMCCodeEmitter(const ARMMCCodeEmitter &); // DO NOT IMPLEMENT
void operator=(const ARMMCCodeEmitter &); // DO NOT IMPLEMENT
const TargetMachine &TM;
const TargetInstrInfo &TII;
MCContext &Ctx;
public:
ARMMCCodeEmitter(TargetMachine &tm, MCContext &ctx)
: TM(tm), TII(*TM.getInstrInfo()), Ctx(ctx) {
}
~ARMMCCodeEmitter() {}
unsigned getNumFixupKinds() const { return ARM::NumTargetFixupKinds; }
const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const {
const static MCFixupKindInfo Infos[] = {
// name off bits flags
{ "fixup_arm_ldst_pcrel_12", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_t2_ldst_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel |
MCFixupKindInfo::FKF_IsAligned},
{ "fixup_arm_pcrel_10", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_t2_pcrel_10", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_adr_pcrel_12", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_branch", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_t2_branch", 0, 32, MCFixupKindInfo::FKF_IsPCRel |
MCFixupKindInfo::FKF_IsAligned},
{ "fixup_arm_thumb_bl", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_blx", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_cb", 0, 16, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_cp", 1, 8, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_movt_hi16", 0, 16, 0 },
{ "fixup_arm_movw_lo16", 0, 16, 0 },
};
if (Kind < FirstTargetFixupKind)
return MCCodeEmitter::getFixupKindInfo(Kind);
assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
"Invalid kind!");
return Infos[Kind - FirstTargetFixupKind];
}
unsigned getMachineSoImmOpValue(unsigned SoImm) const;
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
unsigned getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getMachineOpValue - Return binary encoding of operand. If the machine
/// operand requires relocation, record the relocation and return zero.
unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getMovtImmOpValue - Return the encoding for the movw/movt pair
uint32_t getMovtImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
bool EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx,
unsigned &Reg, unsigned &Imm,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getThumbBLTargetOpValue - Return encoding info for Thumb immediate
/// BL branch target.
uint32_t getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
/// BLX branch target.
uint32_t getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
uint32_t getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getBranchTargetOpValue - Return encoding info for 24-bit immediate
/// branch target.
uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAdrLabelOpValue - Return encoding info for 12-bit immediate
/// ADR label target.
uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12'
/// operand.
uint32_t getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getT2AddrModeImm8s4OpValue - Return encoding info for 'reg +/- imm8<<2'
/// operand.
uint32_t getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getLdStSORegOpValue - Return encoding info for 'reg +/- reg shop imm'
/// operand as needed by load/store instructions.
uint32_t getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getLdStmModeOpValue - Return encoding for load/store multiple mode.
uint32_t getLdStmModeOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
ARM_AM::AMSubMode Mode = (ARM_AM::AMSubMode)MI.getOperand(OpIdx).getImm();
switch (Mode) {
default: assert(0 && "Unknown addressing sub-mode!");
case ARM_AM::da: return 0;
case ARM_AM::ia: return 1;
case ARM_AM::db: return 2;
case ARM_AM::ib: return 3;
}
}
/// getShiftOp - Return the shift opcode (bit[6:5]) of the immediate value.
///
unsigned getShiftOp(ARM_AM::ShiftOpc ShOpc) const {
switch (ShOpc) {
default: llvm_unreachable("Unknown shift opc!");
case ARM_AM::no_shift:
case ARM_AM::lsl: return 0;
case ARM_AM::lsr: return 1;
case ARM_AM::asr: return 2;
case ARM_AM::ror:
case ARM_AM::rrx: return 3;
}
return 0;
}
/// getAddrMode2OpValue - Return encoding for addrmode2 operands.
uint32_t getAddrMode2OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrMode2OffsetOpValue - Return encoding for am2offset operands.
uint32_t getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrMode3OffsetOpValue - Return encoding for am3offset operands.
uint32_t getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrMode3OpValue - Return encoding for addrmode3 operands.
uint32_t getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModeThumbSPOpValue - Return encoding info for 'reg +/- imm12'
/// operand.
uint32_t getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModeS4OpValue - Return encoding for t_addrmode_s4 operands.
uint32_t getAddrModeS4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModeS2OpValue - Return encoding for t_addrmode_s2 operands.
uint32_t getAddrModeS2OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModeS1OpValue - Return encoding for t_addrmode_s1 operands.
uint32_t getAddrModeS1OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
uint32_t getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getAddrMode5OpValue - Return encoding info for 'reg +/- imm8' operand.
uint32_t getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getCCOutOpValue - Return encoding of the 's' bit.
unsigned getCCOutOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
// The operand is either reg0 or CPSR. The 's' bit is encoded as '0' or
// '1' respectively.
return MI.getOperand(Op).getReg() == ARM::CPSR;
}
/// getSOImmOpValue - Return an encoded 12-bit shifted-immediate value.
unsigned getSOImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
unsigned SoImm = MI.getOperand(Op).getImm();
int SoImmVal = ARM_AM::getSOImmVal(SoImm);
assert(SoImmVal != -1 && "Not a valid so_imm value!");
// Encode rotate_imm.
unsigned Binary = (ARM_AM::getSOImmValRot((unsigned)SoImmVal) >> 1)
<< ARMII::SoRotImmShift;
// Encode immed_8.
Binary |= ARM_AM::getSOImmValImm((unsigned)SoImmVal);
return Binary;
}
/// getT2SOImmOpValue - Return an encoded 12-bit shifted-immediate value.
unsigned getT2SOImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
unsigned SoImm = MI.getOperand(Op).getImm();
unsigned Encoded = ARM_AM::getT2SOImmVal(SoImm);
assert(Encoded != ~0U && "Not a Thumb2 so_imm value?");
return Encoded;
}
unsigned getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getT2AddrModeImm8OpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getT2AddrModeImm12OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const;
/// getSORegOpValue - Return an encoded so_reg shifted register value.
unsigned getSORegOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getT2SORegOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getRotImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
switch (MI.getOperand(Op).getImm()) {
default: assert (0 && "Not a valid rot_imm value!");
case 0: return 0;
case 8: return 1;
case 16: return 2;
case 24: return 3;
}
}
unsigned getImmMinusOneOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
return MI.getOperand(Op).getImm() - 1;
}
unsigned getNEONVcvtImm32OpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
return 64 - MI.getOperand(Op).getImm();
}
unsigned getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getRegisterListOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned NEONThumb2DataIPostEncoder(const MCInst &MI,
unsigned EncodedValue) const;
unsigned NEONThumb2LoadStorePostEncoder(const MCInst &MI,
unsigned EncodedValue) const;
unsigned NEONThumb2DupPostEncoder(const MCInst &MI,
unsigned EncodedValue) const;
unsigned VFPThumb2PostEncoder(const MCInst &MI,
unsigned EncodedValue) const;
void EmitByte(unsigned char C, raw_ostream &OS) const {
OS << (char)C;
}
void EmitConstant(uint64_t Val, unsigned Size, raw_ostream &OS) const {
// Output the constant in little endian byte order.
for (unsigned i = 0; i != Size; ++i) {
EmitByte(Val & 255, OS);
Val >>= 8;
}
}
void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups) const;
};
} // end anonymous namespace
MCCodeEmitter *llvm::createARMMCCodeEmitter(const Target &, TargetMachine &TM,
MCContext &Ctx) {
return new ARMMCCodeEmitter(TM, Ctx);
}
/// NEONThumb2DataIPostEncoder - Post-process encoded NEON data-processing
/// instructions, and rewrite them to their Thumb2 form if we are currently in
/// Thumb2 mode.
unsigned ARMMCCodeEmitter::NEONThumb2DataIPostEncoder(const MCInst &MI,
unsigned EncodedValue) const {
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2()) {
// NEON Thumb2 data-processsing encodings are very simple: bit 24 is moved
// to bit 12 of the high half-word (i.e. bit 28), and bits 27-24 are
// set to 1111.
unsigned Bit24 = EncodedValue & 0x01000000;
unsigned Bit28 = Bit24 << 4;
EncodedValue &= 0xEFFFFFFF;
EncodedValue |= Bit28;
EncodedValue |= 0x0F000000;
}
return EncodedValue;
}
/// NEONThumb2LoadStorePostEncoder - Post-process encoded NEON load/store
/// instructions, and rewrite them to their Thumb2 form if we are currently in
/// Thumb2 mode.
unsigned ARMMCCodeEmitter::NEONThumb2LoadStorePostEncoder(const MCInst &MI,
unsigned EncodedValue) const {
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2()) {
EncodedValue &= 0xF0FFFFFF;
EncodedValue |= 0x09000000;
}
return EncodedValue;
}
/// NEONThumb2DupPostEncoder - Post-process encoded NEON vdup
/// instructions, and rewrite them to their Thumb2 form if we are currently in
/// Thumb2 mode.
unsigned ARMMCCodeEmitter::NEONThumb2DupPostEncoder(const MCInst &MI,
unsigned EncodedValue) const {
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2()) {
EncodedValue &= 0x00FFFFFF;
EncodedValue |= 0xEE000000;
}
return EncodedValue;
}
/// VFPThumb2PostEncoder - Post-process encoded VFP instructions and rewrite
/// them to their Thumb2 form if we are currently in Thumb2 mode.
unsigned ARMMCCodeEmitter::
VFPThumb2PostEncoder(const MCInst &MI, unsigned EncodedValue) const {
if (TM.getSubtarget<ARMSubtarget>().isThumb2()) {
EncodedValue &= 0x0FFFFFFF;
EncodedValue |= 0xE0000000;
}
return EncodedValue;
}
/// getMachineOpValue - Return binary encoding of operand. If the machine
/// operand requires relocation, record the relocation and return zero.
unsigned ARMMCCodeEmitter::
getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups) const {
if (MO.isReg()) {
unsigned Reg = MO.getReg();
unsigned RegNo = getARMRegisterNumbering(Reg);
// Q registers are encoded as 2x their register number.
switch (Reg) {
default:
return RegNo;
case ARM::Q0: case ARM::Q1: case ARM::Q2: case ARM::Q3:
case ARM::Q4: case ARM::Q5: case ARM::Q6: case ARM::Q7:
case ARM::Q8: case ARM::Q9: case ARM::Q10: case ARM::Q11:
case ARM::Q12: case ARM::Q13: case ARM::Q14: case ARM::Q15:
return 2 * RegNo;
}
} else if (MO.isImm()) {
return static_cast<unsigned>(MO.getImm());
} else if (MO.isFPImm()) {
return static_cast<unsigned>(APFloat(MO.getFPImm())
.bitcastToAPInt().getHiBits(32).getLimitedValue());
}
llvm_unreachable("Unable to encode MCOperand!");
return 0;
}
/// getAddrModeImmOpValue - Return encoding info for 'reg +/- imm' operand.
bool ARMMCCodeEmitter::
EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx, unsigned &Reg,
unsigned &Imm, SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
Reg = getARMRegisterNumbering(MO.getReg());
int32_t SImm = MO1.getImm();
bool isAdd = true;
// Special value for #-0
if (SImm == INT32_MIN)
SImm = 0;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (SImm < 0) {
SImm = -SImm;
isAdd = false;
}
Imm = SImm;
return isAdd;
}
/// getBranchTargetOpValue - Helper function to get the branch target operand,
/// which is either an immediate or requires a fixup.
static uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
unsigned FixupKind,
SmallVectorImpl<MCFixup> &Fixups) {
const MCOperand &MO = MI.getOperand(OpIdx);
// If the destination is an immediate, we have nothing to do.
if (MO.isImm()) return MO.getImm();
assert(MO.isExpr() && "Unexpected branch target type!");
const MCExpr *Expr = MO.getExpr();
MCFixupKind Kind = MCFixupKind(FixupKind);
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
// All of the information is in the fixup.
return 0;
}
/// getThumbBLTargetOpValue - Return encoding info for immediate branch target.
uint32_t ARMMCCodeEmitter::
getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bl, Fixups);
}
/// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
/// BLX branch target.
uint32_t ARMMCCodeEmitter::
getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_blx, Fixups);
}
/// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
uint32_t ARMMCCodeEmitter::
getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cb, Fixups);
}
/// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
/// target.
uint32_t ARMMCCodeEmitter::
getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_branch, Fixups);
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_branch, Fixups);
}
/// getAdrLabelOpValue - Return encoding info for 12-bit immediate ADR label
/// target.
uint32_t ARMMCCodeEmitter::
getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
assert(MI.getOperand(OpIdx).isExpr() && "Unexpected adr target type!");
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_adr_pcrel_12,
Fixups);
}
/// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12' operand.
uint32_t ARMMCCodeEmitter::
getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {17-13} = reg
// {12} = (U)nsigned (add == '1', sub == '0')
// {11-0} = imm12
unsigned Reg, Imm12;
bool isAdd = true;
// If The first operand isn't a register, we have a label reference.
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO2 = MI.getOperand(OpIdx+1);
if (!MO.isReg() || (MO.getReg() == ARM::PC && MO2.isExpr())) {
Reg = getARMRegisterNumbering(ARM::PC); // Rn is PC.
Imm12 = 0;
isAdd = false ; // 'U' bit is set as part of the fixup.
const MCExpr *Expr = 0;
if (!MO.isReg())
Expr = MO.getExpr();
else
Expr = MO2.getExpr();
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
MCFixupKind Kind;
if (Subtarget.isThumb2())
Kind = MCFixupKind(ARM::fixup_t2_ldst_pcrel_12);
else
Kind = MCFixupKind(ARM::fixup_arm_ldst_pcrel_12);
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
++MCNumCPRelocations;
} else
isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm12, Fixups);
uint32_t Binary = Imm12 & 0xfff;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (isAdd)
Binary |= (1 << 12);
Binary |= (Reg << 13);
return Binary;
}
/// getT2AddrModeImm8s4OpValue - Return encoding info for
/// 'reg +/- imm8<<2' operand.
uint32_t ARMMCCodeEmitter::
getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {17-13} = reg
// {12} = (U)nsigned (add == '1', sub == '0')
// {11-0} = imm8
unsigned Reg, Imm8;
bool isAdd = true;
// If The first operand isn't a register, we have a label reference.
const MCOperand &MO = MI.getOperand(OpIdx);
if (!MO.isReg()) {
Reg = getARMRegisterNumbering(ARM::PC); // Rn is PC.
Imm8 = 0;
isAdd = false ; // 'U' bit is set as part of the fixup.
assert(MO.isExpr() && "Unexpected machine operand type!");
const MCExpr *Expr = MO.getExpr();
MCFixupKind Kind = MCFixupKind(ARM::fixup_arm_pcrel_10);
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
++MCNumCPRelocations;
} else
isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups);
uint32_t Binary = (Imm8 >> 2) & 0xff;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (isAdd)
Binary |= (1 << 9);
Binary |= (Reg << 9);
return Binary;
}
uint32_t ARMMCCodeEmitter::
getMovtImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {20-16} = imm{15-12}
// {11-0} = imm{11-0}
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isImm()) {
return static_cast<unsigned>(MO.getImm());
} else if (const MCSymbolRefExpr *Expr =
dyn_cast<MCSymbolRefExpr>(MO.getExpr())) {
MCFixupKind Kind;
switch (Expr->getKind()) {
default: assert(0 && "Unsupported ARMFixup");
case MCSymbolRefExpr::VK_ARM_HI16:
Kind = MCFixupKind(ARM::fixup_arm_movt_hi16);
break;
case MCSymbolRefExpr::VK_ARM_LO16:
Kind = MCFixupKind(ARM::fixup_arm_movw_lo16);
break;
}
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
return 0;
};
llvm_unreachable("Unsupported MCExpr type in MCOperand!");
return 0;
}
uint32_t ARMMCCodeEmitter::
getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
const MCOperand &MO2 = MI.getOperand(OpIdx+2);
unsigned Rn = getARMRegisterNumbering(MO.getReg());
unsigned Rm = getARMRegisterNumbering(MO1.getReg());
unsigned ShImm = ARM_AM::getAM2Offset(MO2.getImm());
bool isAdd = ARM_AM::getAM2Op(MO2.getImm()) == ARM_AM::add;
ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(MO2.getImm());
unsigned SBits = getShiftOp(ShOp);
// {16-13} = Rn
// {12} = isAdd
// {11-0} = shifter
// {3-0} = Rm
// {4} = 0
// {6-5} = type
// {11-7} = imm
uint32_t Binary = Rm;
Binary |= Rn << 13;
Binary |= SBits << 5;
Binary |= ShImm << 7;
if (isAdd)
Binary |= 1 << 12;
return Binary;
}
uint32_t ARMMCCodeEmitter::
getAddrMode2OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {17-14} Rn
// {13} 1 == imm12, 0 == Rm
// {12} isAdd
// {11-0} imm12/Rm
const MCOperand &MO = MI.getOperand(OpIdx);
unsigned Rn = getARMRegisterNumbering(MO.getReg());
uint32_t Binary = getAddrMode2OffsetOpValue(MI, OpIdx + 1, Fixups);
Binary |= Rn << 14;
return Binary;
}
uint32_t ARMMCCodeEmitter::
getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {13} 1 == imm12, 0 == Rm
// {12} isAdd
// {11-0} imm12/Rm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
unsigned Imm = MO1.getImm();
bool isAdd = ARM_AM::getAM2Op(Imm) == ARM_AM::add;
bool isReg = MO.getReg() != 0;
uint32_t Binary = ARM_AM::getAM2Offset(Imm);
// if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm12
if (isReg) {
ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(Imm);
Binary <<= 7; // Shift amount is bits [11:7]
Binary |= getShiftOp(ShOp) << 5; // Shift type is bits [6:5]
Binary |= getARMRegisterNumbering(MO.getReg()); // Rm is bits [3:0]
}
return Binary | (isAdd << 12) | (isReg << 13);
}
uint32_t ARMMCCodeEmitter::
getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {9} 1 == imm8, 0 == Rm
// {8} isAdd
// {7-4} imm7_4/zero
// {3-0} imm3_0/Rm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
unsigned Imm = MO1.getImm();
bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
bool isImm = MO.getReg() == 0;
uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
// if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
if (!isImm)
Imm8 = getARMRegisterNumbering(MO.getReg());
return Imm8 | (isAdd << 8) | (isImm << 9);
}
uint32_t ARMMCCodeEmitter::
getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {13} 1 == imm8, 0 == Rm
// {12-9} Rn
// {8} isAdd
// {7-4} imm7_4/zero
// {3-0} imm3_0/Rm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
const MCOperand &MO2 = MI.getOperand(OpIdx+2);
unsigned Rn = getARMRegisterNumbering(MO.getReg());
unsigned Imm = MO2.getImm();
bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
bool isImm = MO1.getReg() == 0;
uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
// if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
if (!isImm)
Imm8 = getARMRegisterNumbering(MO1.getReg());
return (Rn << 9) | Imm8 | (isAdd << 8) | (isImm << 13);
}
/// getAddrModeThumbSPOpValue - Encode the t_addrmode_sp operands.
uint32_t ARMMCCodeEmitter::
getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// [SP, #imm]
// {7-0} = imm8
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
#if 0 // FIXME: This crashes2003-05-14-initialize-string.c
assert(MI.getOperand(OpIdx).getReg() == ARM::SP &&
"Unexpected base register!");
#endif
// The immediate is already shifted for the implicit zeroes, so no change
// here.
return MO1.getImm() & 0xff;
}
/// getAddrModeSOpValue - Encode the t_addrmode_s# operands.
static unsigned getAddrModeSOpValue(const MCInst &MI, unsigned OpIdx,
unsigned Scale) {
// [Rn, Rm]
// {5-3} = Rm
// {2-0} = Rn
//
// [Rn, #imm]
// {7-3} = imm5
// {2-0} = Rn
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
const MCOperand &MO2 = MI.getOperand(OpIdx + 2);
unsigned Rn = getARMRegisterNumbering(MO.getReg());
unsigned Imm5 = (MO1.getImm() / Scale) & 0x1f;
if (MO2.getReg() != 0)
// Is an immediate.
Imm5 = getARMRegisterNumbering(MO2.getReg());
return (Imm5 << 3) | Rn;
}
/// getAddrModeS4OpValue - Return encoding for t_addrmode_s4 operands.
uint32_t ARMMCCodeEmitter::
getAddrModeS4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &) const {
return getAddrModeSOpValue(MI, OpIdx, 4);
}
/// getAddrModeS2OpValue - Return encoding for t_addrmode_s2 operands.
uint32_t ARMMCCodeEmitter::
getAddrModeS2OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &) const {
return getAddrModeSOpValue(MI, OpIdx, 2);
}
/// getAddrModeS1OpValue - Return encoding for t_addrmode_s1 operands.
uint32_t ARMMCCodeEmitter::
getAddrModeS1OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &) const {
return getAddrModeSOpValue(MI, OpIdx, 1);
}
/// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
uint32_t ARMMCCodeEmitter::
getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cp, Fixups);
}
/// getAddrMode5OpValue - Return encoding info for 'reg +/- imm10' operand.
uint32_t ARMMCCodeEmitter::
getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// {12-9} = reg
// {8} = (U)nsigned (add == '1', sub == '0')
// {7-0} = imm8
unsigned Reg, Imm8;
bool isAdd;
// If The first operand isn't a register, we have a label reference.
const MCOperand &MO = MI.getOperand(OpIdx);
if (!MO.isReg()) {
Reg = getARMRegisterNumbering(ARM::PC); // Rn is PC.
Imm8 = 0;
isAdd = false; // 'U' bit is handled as part of the fixup.
assert(MO.isExpr() && "Unexpected machine operand type!");
const MCExpr *Expr = MO.getExpr();
MCFixupKind Kind;
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2())
Kind = MCFixupKind(ARM::fixup_t2_pcrel_10);
else
Kind = MCFixupKind(ARM::fixup_arm_pcrel_10);
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
++MCNumCPRelocations;
} else {
EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups);
isAdd = ARM_AM::getAM5Op(Imm8) == ARM_AM::add;
}
uint32_t Binary = ARM_AM::getAM5Offset(Imm8);
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (isAdd)
Binary |= (1 << 8);
Binary |= (Reg << 9);
return Binary;
}
unsigned ARMMCCodeEmitter::
getSORegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// Sub-operands are [reg, reg, imm]. The first register is Rm, the reg to be
// shifted. The second is either Rs, the amount to shift by, or reg0 in which
// case the imm contains the amount to shift by.
//
// {3-0} = Rm.
// {4} = 1 if reg shift, 0 if imm shift
// {6-5} = type
// If reg shift:
// {11-8} = Rs
// {7} = 0
// else (imm shift)
// {11-7} = imm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
const MCOperand &MO2 = MI.getOperand(OpIdx + 2);
ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO2.getImm());
// Encode Rm.
unsigned Binary = getARMRegisterNumbering(MO.getReg());
// Encode the shift opcode.
unsigned SBits = 0;
unsigned Rs = MO1.getReg();
if (Rs) {
// Set shift operand (bit[7:4]).
// LSL - 0001
// LSR - 0011
// ASR - 0101
// ROR - 0111
// RRX - 0110 and bit[11:8] clear.
switch (SOpc) {
default: llvm_unreachable("Unknown shift opc!");
case ARM_AM::lsl: SBits = 0x1; break;
case ARM_AM::lsr: SBits = 0x3; break;
case ARM_AM::asr: SBits = 0x5; break;
case ARM_AM::ror: SBits = 0x7; break;
case ARM_AM::rrx: SBits = 0x6; break;
}
} else {
// Set shift operand (bit[6:4]).
// LSL - 000
// LSR - 010
// ASR - 100
// ROR - 110
switch (SOpc) {
default: llvm_unreachable("Unknown shift opc!");
case ARM_AM::lsl: SBits = 0x0; break;
case ARM_AM::lsr: SBits = 0x2; break;
case ARM_AM::asr: SBits = 0x4; break;
case ARM_AM::ror: SBits = 0x6; break;
}
}
Binary |= SBits << 4;
if (SOpc == ARM_AM::rrx)
return Binary;
// Encode the shift operation Rs or shift_imm (except rrx).
if (Rs) {
// Encode Rs bit[11:8].
assert(ARM_AM::getSORegOffset(MO2.getImm()) == 0);
return Binary | (getARMRegisterNumbering(Rs) << ARMII::RegRsShift);
}
// Encode shift_imm bit[11:7].
return Binary | ARM_AM::getSORegOffset(MO2.getImm()) << 7;
}
unsigned ARMMCCodeEmitter::
getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO1 = MI.getOperand(OpNum);
const MCOperand &MO2 = MI.getOperand(OpNum+1);
const MCOperand &MO3 = MI.getOperand(OpNum+2);
// Encoded as [Rn, Rm, imm].
// FIXME: Needs fixup support.
unsigned Value = getARMRegisterNumbering(MO1.getReg());
Value <<= 4;
Value |= getARMRegisterNumbering(MO2.getReg());
Value <<= 2;
Value |= MO3.getImm();
return Value;
}
unsigned ARMMCCodeEmitter::
getT2AddrModeImm8OpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO1 = MI.getOperand(OpNum);
const MCOperand &MO2 = MI.getOperand(OpNum+1);
// FIXME: Needs fixup support.
unsigned Value = getARMRegisterNumbering(MO1.getReg());
// Even though the immediate is 8 bits long, we need 9 bits in order
// to represent the (inverse of the) sign bit.
Value <<= 9;
int32_t tmp = (int32_t)MO2.getImm();
if (tmp < 0)
tmp = abs(tmp);
else
Value |= 256; // Set the ADD bit
Value |= tmp & 255;
return Value;
}
unsigned ARMMCCodeEmitter::
getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO1 = MI.getOperand(OpNum);
// FIXME: Needs fixup support.
unsigned Value = 0;
int32_t tmp = (int32_t)MO1.getImm();
if (tmp < 0)
tmp = abs(tmp);
else
Value |= 256; // Set the ADD bit
Value |= tmp & 255;
return Value;
}
unsigned ARMMCCodeEmitter::
getT2AddrModeImm12OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO1 = MI.getOperand(OpNum);
// FIXME: Needs fixup support.
unsigned Value = 0;
int32_t tmp = (int32_t)MO1.getImm();
if (tmp < 0)
tmp = abs(tmp);
else
Value |= 4096; // Set the ADD bit
Value |= tmp & 4095;
return Value;
}
unsigned ARMMCCodeEmitter::
getT2SORegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
// Sub-operands are [reg, imm]. The first register is Rm, the reg to be
// shifted. The second is the amount to shift by.
//
// {3-0} = Rm.
// {4} = 0
// {6-5} = type
// {11-7} = imm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO1.getImm());
// Encode Rm.
unsigned Binary = getARMRegisterNumbering(MO.getReg());
// Encode the shift opcode.
unsigned SBits = 0;
// Set shift operand (bit[6:4]).
// LSL - 000
// LSR - 010
// ASR - 100
// ROR - 110
switch (SOpc) {
default: llvm_unreachable("Unknown shift opc!");
case ARM_AM::lsl: SBits = 0x0; break;
case ARM_AM::lsr: SBits = 0x2; break;
case ARM_AM::asr: SBits = 0x4; break;
case ARM_AM::ror: SBits = 0x6; break;
}
Binary |= SBits << 4;
if (SOpc == ARM_AM::rrx)
return Binary;
// Encode shift_imm bit[11:7].
return Binary | ARM_AM::getSORegOffset(MO1.getImm()) << 7;
}
unsigned ARMMCCodeEmitter::
getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
// 10 bits. lower 5 bits are are the lsb of the mask, high five bits are the
// msb of the mask.
const MCOperand &MO = MI.getOperand(Op);
uint32_t v = ~MO.getImm();
uint32_t lsb = CountTrailingZeros_32(v);
uint32_t msb = (32 - CountLeadingZeros_32 (v)) - 1;
assert (v != 0 && lsb < 32 && msb < 32 && "Illegal bitfield mask!");
return lsb | (msb << 5);
}
unsigned ARMMCCodeEmitter::
getRegisterListOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
// VLDM/VSTM:
// {12-8} = Vd
// {7-0} = Number of registers
//
// LDM/STM:
// {15-0} = Bitfield of GPRs.
unsigned Reg = MI.getOperand(Op).getReg();
bool SPRRegs = ARM::SPRRegClass.contains(Reg);
bool DPRRegs = ARM::DPRRegClass.contains(Reg);
unsigned Binary = 0;
if (SPRRegs || DPRRegs) {
// VLDM/VSTM
unsigned RegNo = getARMRegisterNumbering(Reg);
unsigned NumRegs = (MI.getNumOperands() - Op) & 0xff;
Binary |= (RegNo & 0x1f) << 8;
if (SPRRegs)
Binary |= NumRegs;
else
Binary |= NumRegs * 2;
} else {
for (unsigned I = Op, E = MI.getNumOperands(); I < E; ++I) {
unsigned RegNo = getARMRegisterNumbering(MI.getOperand(I).getReg());
Binary |= 1 << RegNo;
}
}
return Binary;
}
/// getAddrMode6AddressOpValue - Encode an addrmode6 register number along
/// with the alignment operand.
unsigned ARMMCCodeEmitter::
getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &Reg = MI.getOperand(Op);
const MCOperand &Imm = MI.getOperand(Op + 1);
unsigned RegNo = getARMRegisterNumbering(Reg.getReg());
unsigned Align = 0;
switch (Imm.getImm()) {
default: break;
case 2:
case 4:
case 8: Align = 0x01; break;
case 16: Align = 0x02; break;
case 32: Align = 0x03; break;
}
return RegNo | (Align << 4);
}
/// getAddrMode6DupAddressOpValue - Encode an addrmode6 register number and
/// alignment operand for use in VLD-dup instructions. This is the same as
/// getAddrMode6AddressOpValue except for the alignment encoding, which is
/// different for VLD4-dup.
unsigned ARMMCCodeEmitter::
getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &Reg = MI.getOperand(Op);
const MCOperand &Imm = MI.getOperand(Op + 1);
unsigned RegNo = getARMRegisterNumbering(Reg.getReg());
unsigned Align = 0;
switch (Imm.getImm()) {
default: break;
case 2:
case 4:
case 8: Align = 0x01; break;
case 16: Align = 0x03; break;
}
return RegNo | (Align << 4);
}
unsigned ARMMCCodeEmitter::
getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(Op);
if (MO.getReg() == 0) return 0x0D;
return MO.getReg();
}
void ARMMCCodeEmitter::
EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups) const {
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
// Pseudo instructions don't get encoded.
const TargetInstrDesc &Desc = TII.get(MI.getOpcode());
uint64_t TSFlags = Desc.TSFlags;
if ((TSFlags & ARMII::FormMask) == ARMII::Pseudo)
return;
int Size;
// Basic size info comes from the TSFlags field.
switch ((TSFlags & ARMII::SizeMask) >> ARMII::SizeShift) {
default: llvm_unreachable("Unexpected instruction size!");
case ARMII::Size2Bytes: Size = 2; break;
case ARMII::Size4Bytes: Size = 4; break;
}
uint32_t Binary = getBinaryCodeForInstr(MI, Fixups);
// Thumb 32-bit wide instructions need to be have the high order halfword
// emitted first.
if (Subtarget.isThumb() && Size == 4) {
EmitConstant(Binary >> 16, 2, OS);
EmitConstant(Binary & 0xffff, 2, OS);
} else
EmitConstant(Binary, Size, OS);
++MCNumEmitted; // Keep track of the # of mi's emitted.
}
#include "ARMGenMCCodeEmitter.inc"