llvm-6502/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp
Asiri Rathnayake dc05f3a64b Add support for ARM modified-immediate assembly syntax.
Certain ARM instructions accept 32-bit immediate operands encoded as a 8-bit
integer value (0-255) and a 4-bit rotation (0-30, even). Current ARM assembly
syntax support in LLVM allows the decoded (32-bit) immediate to be specified
as a single immediate operand for such instructions:

mov r0, #4278190080

The ARMARM defines an extended assembly syntax allowing the encoding to be made
more explicit, as in:

mov r0, #255, #8 ; (same 32-bit value as above)

The behaviour of the two instructions can be different w.r.t flags, which is
documented under "Modified immediate constants" in ARMARM. This patch enables
support for this extended syntax at the MC layer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223113 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-02 10:53:20 +00:00

1698 lines
62 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.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/ARMMCTargetDesc.h"
#include "MCTargetDesc/ARMAddressingModes.h"
#include "MCTargetDesc/ARMBaseInfo.h"
#include "MCTargetDesc/ARMFixupKinds.h"
#include "MCTargetDesc/ARMMCExpr.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "mccodeemitter"
STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
STATISTIC(MCNumCPRelocations, "Number of constant pool relocations created.");
namespace {
class ARMMCCodeEmitter : public MCCodeEmitter {
ARMMCCodeEmitter(const ARMMCCodeEmitter &) LLVM_DELETED_FUNCTION;
void operator=(const ARMMCCodeEmitter &) LLVM_DELETED_FUNCTION;
const MCInstrInfo &MCII;
const MCContext &CTX;
bool IsLittleEndian;
public:
ARMMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx, bool IsLittle)
: MCII(mcii), CTX(ctx), IsLittleEndian(IsLittle) {
}
~ARMMCCodeEmitter() {}
bool isThumb(const MCSubtargetInfo &STI) const {
return (STI.getFeatureBits() & ARM::ModeThumb) != 0;
}
bool isThumb2(const MCSubtargetInfo &STI) const {
return isThumb(STI) && (STI.getFeatureBits() & ARM::FeatureThumb2) != 0;
}
bool isTargetMachO(const MCSubtargetInfo &STI) const {
Triple TT(STI.getTargetTriple());
return TT.isOSBinFormatMachO();
}
unsigned getMachineSoImmOpValue(unsigned SoImm) const;
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
uint64_t getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) const;
/// getHiLo16ImmOpValue - Return the encoding for the hi / low 16-bit of
/// the specified operand. This is used for operands with :lower16: and
/// :upper16: prefixes.
uint32_t getHiLo16ImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
bool EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx,
unsigned &Reg, unsigned &Imm,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbBLTargetOpValue - Return encoding info for Thumb immediate
/// BL branch target.
uint32_t getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
/// BLX branch target.
uint32_t getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
uint32_t getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
uint32_t getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
uint32_t getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getBranchTargetOpValue - Return encoding info for 24-bit immediate
/// branch target.
uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
/// immediate Thumb2 direct branch target.
uint32_t getUnconditionalBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getARMBranchTargetOpValue - Return encoding info for 24-bit immediate
/// branch target.
uint32_t getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
uint32_t getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
uint32_t getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAdrLabelOpValue - Return encoding info for 12-bit immediate
/// ADR label target.
uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
uint32_t getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
uint32_t getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12'
/// operand.
uint32_t getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getThumbAddrModeRegRegOpValue - Return encoding for 'reg + reg' operand.
uint32_t getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getT2AddrModeImm8s4OpValue - Return encoding info for 'reg +/- imm8<<2'
/// operand.
uint32_t getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getT2AddrModeImm0_1020s4OpValue - Return encoding info for 'reg + imm8<<2'
/// operand.
uint32_t getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getT2Imm8s4OpValue - Return encoding info for '+/- imm8<<2'
/// operand.
uint32_t getT2Imm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) const;
/// getLdStmModeOpValue - Return encoding for load/store multiple mode.
uint32_t getLdStmModeOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
ARM_AM::AMSubMode Mode = (ARM_AM::AMSubMode)MI.getOperand(OpIdx).getImm();
switch (Mode) {
default: llvm_unreachable("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) {
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;
}
llvm_unreachable("Invalid ShiftOpc!");
}
/// getAddrMode2OpValue - Return encoding for addrmode2 operands.
uint32_t getAddrMode2OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrMode2OffsetOpValue - Return encoding for am2offset operands.
uint32_t getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getPostIdxRegOpValue - Return encoding for postidx_reg operands.
uint32_t getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrMode3OffsetOpValue - Return encoding for am3offset operands.
uint32_t getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrMode3OpValue - Return encoding for addrmode3 operands.
uint32_t getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrModeThumbSPOpValue - Return encoding info for 'reg +/- imm12'
/// operand.
uint32_t getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
uint32_t getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
uint32_t getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getAddrMode5OpValue - Return encoding info for 'reg +/- imm8' operand.
uint32_t getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getCCOutOpValue - Return encoding of the 's' bit.
unsigned getCCOutOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(Op);
// We expect MO to be an immediate or an expression,
// if it is an immediate - that's fine, just encode the value.
// Otherwise - create a Fixup.
if (MO.isExpr()) {
const MCExpr *Expr = MO.getExpr();
// In instruction code this value always encoded as lowest 12 bits,
// so we don't have to perform any specific adjustments.
// Due to requirements of relocatable records we have to use FK_Data_4.
// See ARMELFObjectWriter::ExplicitRelSym and
// ARMELFObjectWriter::GetRelocTypeInner for more details.
MCFixupKind Kind = MCFixupKind(FK_Data_4);
Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
return 0;
}
unsigned SoImm = MO.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;
}
unsigned getModImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &ST) const {
const MCOperand &MO = MI.getOperand(Op);
// Support for fixups (MCFixup)
if (MO.isExpr()) {
const MCExpr *Expr = MO.getExpr();
// In instruction code this value always encoded as lowest 12 bits,
// so we don't have to perform any specific adjustments.
// Due to requirements of relocatable records we have to use FK_Data_4.
// See ARMELFObjectWriter::ExplicitRelSym and
// ARMELFObjectWriter::GetRelocTypeInner for more details.
MCFixupKind Kind = MCFixupKind(FK_Data_4);
Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
return 0;
}
// Immediate is already in its encoded format
return MO.getImm();
}
/// getT2SOImmOpValue - Return an encoded 12-bit shifted-immediate value.
unsigned getT2SOImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) const;
unsigned getT2AddrModeImm8OpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getT2AddrModeImm12OffsetOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getSORegOpValue - Return an encoded so_reg shifted register value.
unsigned getSORegRegOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getSORegImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getT2SORegOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getNEONVcvtImm32OpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
return 64 - MI.getOperand(Op).getImm();
}
unsigned getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getRegisterListOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getShiftRight8Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getShiftRight16Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getShiftRight32Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getShiftRight64Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getThumbSRImmOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned NEONThumb2DataIPostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) const;
unsigned NEONThumb2LoadStorePostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) const;
unsigned NEONThumb2DupPostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) const;
unsigned NEONThumb2V8PostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) const;
unsigned VFPThumb2PostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) 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) {
unsigned Shift = IsLittleEndian ? i * 8 : (Size - 1 - i) * 8;
EmitByte((Val >> Shift) & 0xff, OS);
}
}
void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const override;
};
} // end anonymous namespace
MCCodeEmitter *llvm::createARMLEMCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
const MCSubtargetInfo &STI,
MCContext &Ctx) {
return new ARMMCCodeEmitter(MCII, Ctx, true);
}
MCCodeEmitter *llvm::createARMBEMCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
const MCSubtargetInfo &STI,
MCContext &Ctx) {
return new ARMMCCodeEmitter(MCII, Ctx, false);
}
/// 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 MCSubtargetInfo &STI) const {
if (isThumb2(STI)) {
// 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 MCSubtargetInfo &STI) const {
if (isThumb2(STI)) {
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 MCSubtargetInfo &STI) const {
if (isThumb2(STI)) {
EncodedValue &= 0x00FFFFFF;
EncodedValue |= 0xEE000000;
}
return EncodedValue;
}
/// Post-process encoded NEON v8 instructions, and rewrite them to Thumb2 form
/// if we are in Thumb2.
unsigned ARMMCCodeEmitter::NEONThumb2V8PostEncoder(const MCInst &MI,
unsigned EncodedValue,
const MCSubtargetInfo &STI) const {
if (isThumb2(STI)) {
EncodedValue |= 0xC000000; // Set bits 27-26
}
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 MCSubtargetInfo &STI) const {
if (isThumb2(STI)) {
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 MCSubtargetInfo &STI) const {
if (MO.isReg()) {
unsigned Reg = MO.getReg();
unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(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!");
}
/// getAddrModeImmOpValue - Return encoding info for 'reg +/- imm' operand.
bool ARMMCCodeEmitter::
EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx, unsigned &Reg,
unsigned &Imm, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
int32_t SImm = MO1.getImm();
bool isAdd = true;
// Special value for #-0
if (SImm == INT32_MIN) {
SImm = 0;
isAdd = false;
}
// 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 MCSubtargetInfo &STI) {
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, MI.getLoc()));
// All of the information is in the fixup.
return 0;
}
// Thumb BL and BLX use a strange offset encoding where bits 22 and 21 are
// determined by negating them and XOR'ing them with bit 23.
static int32_t encodeThumbBLOffset(int32_t offset) {
offset >>= 1;
uint32_t S = (offset & 0x800000) >> 23;
uint32_t J1 = (offset & 0x400000) >> 22;
uint32_t J2 = (offset & 0x200000) >> 21;
J1 = (~J1 & 0x1);
J2 = (~J2 & 0x1);
J1 ^= S;
J2 ^= S;
offset &= ~0x600000;
offset |= J1 << 22;
offset |= J2 << 21;
return offset;
}
/// getThumbBLTargetOpValue - Return encoding info for immediate branch target.
uint32_t ARMMCCodeEmitter::
getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bl,
Fixups, STI);
return encodeThumbBLOffset(MO.getImm());
}
/// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
/// BLX branch target.
uint32_t ARMMCCodeEmitter::
getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_blx,
Fixups, STI);
return encodeThumbBLOffset(MO.getImm());
}
/// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
uint32_t ARMMCCodeEmitter::
getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_br,
Fixups, STI);
return (MO.getImm() >> 1);
}
/// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
uint32_t ARMMCCodeEmitter::
getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bcc,
Fixups, STI);
return (MO.getImm() >> 1);
}
/// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
uint32_t ARMMCCodeEmitter::
getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cb, Fixups, STI);
return (MO.getImm() >> 1);
}
/// Return true if this branch has a non-always predication
static bool HasConditionalBranch(const MCInst &MI) {
int NumOp = MI.getNumOperands();
if (NumOp >= 2) {
for (int i = 0; i < NumOp-1; ++i) {
const MCOperand &MCOp1 = MI.getOperand(i);
const MCOperand &MCOp2 = MI.getOperand(i + 1);
if (MCOp1.isImm() && MCOp2.isReg() &&
(MCOp2.getReg() == 0 || MCOp2.getReg() == ARM::CPSR)) {
if (ARMCC::CondCodes(MCOp1.getImm()) != ARMCC::AL)
return true;
}
}
}
return false;
}
/// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
/// target.
uint32_t ARMMCCodeEmitter::
getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// FIXME: This really, really shouldn't use TargetMachine. We don't want
// coupling between MC and TM anywhere we can help it.
if (isThumb2(STI))
return
::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_condbranch, Fixups, STI);
return getARMBranchTargetOpValue(MI, OpIdx, Fixups, STI);
}
/// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
/// target.
uint32_t ARMMCCodeEmitter::
getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr()) {
if (HasConditionalBranch(MI))
return ::getBranchTargetOpValue(MI, OpIdx,
ARM::fixup_arm_condbranch, Fixups, STI);
return ::getBranchTargetOpValue(MI, OpIdx,
ARM::fixup_arm_uncondbranch, Fixups, STI);
}
return MO.getImm() >> 2;
}
uint32_t ARMMCCodeEmitter::
getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr()) {
if (HasConditionalBranch(MI))
return ::getBranchTargetOpValue(MI, OpIdx,
ARM::fixup_arm_condbl, Fixups, STI);
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_uncondbl, Fixups, STI);
}
return MO.getImm() >> 2;
}
uint32_t ARMMCCodeEmitter::
getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_blx, Fixups, STI);
return MO.getImm() >> 1;
}
/// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
/// immediate branch target.
uint32_t ARMMCCodeEmitter::
getUnconditionalBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
unsigned Val = 0;
const MCOperand MO = MI.getOperand(OpIdx);
if(MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_uncondbranch, Fixups, STI);
else
Val = MO.getImm() >> 1;
bool I = (Val & 0x800000);
bool J1 = (Val & 0x400000);
bool J2 = (Val & 0x200000);
if (I ^ J1)
Val &= ~0x400000;
else
Val |= 0x400000;
if (I ^ J2)
Val &= ~0x200000;
else
Val |= 0x200000;
return Val;
}
/// getAdrLabelOpValue - Return encoding info for 12-bit shifted-immediate
/// ADR label target.
uint32_t ARMMCCodeEmitter::
getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_adr_pcrel_12,
Fixups, STI);
int64_t offset = MO.getImm();
uint32_t Val = 0x2000;
int SoImmVal;
if (offset == INT32_MIN) {
Val = 0x1000;
SoImmVal = 0;
} else if (offset < 0) {
Val = 0x1000;
offset *= -1;
SoImmVal = ARM_AM::getSOImmVal(offset);
if(SoImmVal == -1) {
Val = 0x2000;
offset *= -1;
SoImmVal = ARM_AM::getSOImmVal(offset);
}
} else {
SoImmVal = ARM_AM::getSOImmVal(offset);
if(SoImmVal == -1) {
Val = 0x1000;
offset *= -1;
SoImmVal = ARM_AM::getSOImmVal(offset);
}
}
assert(SoImmVal != -1 && "Not a valid so_imm value!");
Val |= SoImmVal;
return Val;
}
/// getT2AdrLabelOpValue - Return encoding info for 12-bit immediate ADR label
/// target.
uint32_t ARMMCCodeEmitter::
getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_adr_pcrel_12,
Fixups, STI);
int32_t Val = MO.getImm();
if (Val == INT32_MIN)
Val = 0x1000;
else if (Val < 0) {
Val *= -1;
Val |= 0x1000;
}
return Val;
}
/// getThumbAdrLabelOpValue - Return encoding info for 8-bit immediate ADR label
/// target.
uint32_t ARMMCCodeEmitter::
getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_thumb_adr_pcrel_10,
Fixups, STI);
return MO.getImm();
}
/// getThumbAddrModeRegRegOpValue - Return encoding info for 'reg + reg'
/// operand.
uint32_t ARMMCCodeEmitter::
getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &,
const MCSubtargetInfo &STI) const {
// [Rn, Rm]
// {5-3} = Rm
// {2-0} = Rn
const MCOperand &MO1 = MI.getOperand(OpIdx);
const MCOperand &MO2 = MI.getOperand(OpIdx + 1);
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
return (Rm << 3) | Rn;
}
/// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12' operand.
uint32_t ARMMCCodeEmitter::
getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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);
if (!MO.isReg()) {
Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC); // Rn is PC.
Imm12 = 0;
if (MO.isExpr()) {
const MCExpr *Expr = MO.getExpr();
isAdd = false ; // 'U' bit is set as part of the fixup.
MCFixupKind Kind;
if (isThumb2(STI))
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, MI.getLoc()));
++MCNumCPRelocations;
} else {
Reg = ARM::PC;
int32_t Offset = MO.getImm();
if (Offset == INT32_MIN) {
Offset = 0;
isAdd = false;
} else if (Offset < 0) {
Offset *= -1;
isAdd = false;
}
Imm12 = Offset;
}
} else
isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm12, Fixups, STI);
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;
}
/// getT2Imm8s4OpValue - Return encoding info for
/// '+/- imm8<<2' operand.
uint32_t ARMMCCodeEmitter::
getT2Imm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// FIXME: The immediate operand should have already been encoded like this
// before ever getting here. The encoder method should just need to combine
// the MI operands for the register and the offset into a single
// representation for the complex operand in the .td file. This isn't just
// style, unfortunately. As-is, we can't represent the distinct encoding
// for #-0.
// {8} = (U)nsigned (add == '1', sub == '0')
// {7-0} = imm8
int32_t Imm8 = MI.getOperand(OpIdx).getImm();
bool isAdd = Imm8 >= 0;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (Imm8 < 0)
Imm8 = -(uint32_t)Imm8;
// Scaled by 4.
Imm8 /= 4;
uint32_t Binary = Imm8 & 0xff;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (isAdd)
Binary |= (1 << 8);
return Binary;
}
/// getT2AddrModeImm8s4OpValue - Return encoding info for
/// 'reg +/- imm8<<2' operand.
uint32_t ARMMCCodeEmitter::
getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// {12-9} = reg
// {8} = (U)nsigned (add == '1', sub == '0')
// {7-0} = 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 = CTX.getRegisterInfo()->getEncodingValue(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_t2_pcrel_10);
Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
++MCNumCPRelocations;
} else
isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
// FIXME: The immediate operand should have already been encoded like this
// before ever getting here. The encoder method should just need to combine
// the MI operands for the register and the offset into a single
// representation for the complex operand in the .td file. This isn't just
// style, unfortunately. As-is, we can't represent the distinct encoding
// for #-0.
uint32_t Binary = (Imm8 >> 2) & 0xff;
// Immediate is always encoded as positive. The 'U' bit controls add vs sub.
if (isAdd)
Binary |= (1 << 8);
Binary |= (Reg << 9);
return Binary;
}
/// getT2AddrModeImm0_1020s4OpValue - Return encoding info for
/// 'reg + imm8<<2' operand.
uint32_t ARMMCCodeEmitter::
getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// {11-8} = reg
// {7-0} = imm8
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
unsigned Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
unsigned Imm8 = MO1.getImm();
return (Reg << 8) | Imm8;
}
uint32_t
ARMMCCodeEmitter::getHiLo16ImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// {20-16} = imm{15-12}
// {11-0} = imm{11-0}
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isImm())
// Hi / lo 16 bits already extracted during earlier passes.
return static_cast<unsigned>(MO.getImm());
// Handle :upper16: and :lower16: assembly prefixes.
const MCExpr *E = MO.getExpr();
MCFixupKind Kind;
if (E->getKind() == MCExpr::Target) {
const ARMMCExpr *ARM16Expr = cast<ARMMCExpr>(E);
E = ARM16Expr->getSubExpr();
if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(E)) {
const int64_t Value = MCE->getValue();
if (Value > UINT32_MAX)
report_fatal_error("constant value truncated (limited to 32-bit)");
switch (ARM16Expr->getKind()) {
case ARMMCExpr::VK_ARM_HI16:
return (int32_t(Value) & 0xffff0000) >> 16;
case ARMMCExpr::VK_ARM_LO16:
return (int32_t(Value) & 0x0000ffff);
default: llvm_unreachable("Unsupported ARMFixup");
}
}
switch (ARM16Expr->getKind()) {
default: llvm_unreachable("Unsupported ARMFixup");
case ARMMCExpr::VK_ARM_HI16:
Kind = MCFixupKind(isThumb2(STI) ? ARM::fixup_t2_movt_hi16
: ARM::fixup_arm_movt_hi16);
break;
case ARMMCExpr::VK_ARM_LO16:
Kind = MCFixupKind(isThumb2(STI) ? ARM::fixup_t2_movw_lo16
: ARM::fixup_arm_movw_lo16);
break;
}
Fixups.push_back(MCFixup::Create(0, E, Kind, MI.getLoc()));
return 0;
}
// If the expression doesn't have :upper16: or :lower16: on it,
// it's just a plain immediate expression, previously those evaluated to
// the lower 16 bits of the expression regardless of whether
// we have a movt or a movw, but that led to misleadingly results.
// This is now disallowed in the the AsmParser in validateInstruction()
// so this should never happen.
llvm_unreachable("expression without :upper16: or :lower16:");
}
uint32_t ARMMCCodeEmitter::
getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
const MCOperand &MO2 = MI.getOperand(OpIdx+2);
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(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);
// While "lsr #32" and "asr #32" exist, they are encoded with a 0 in the shift
// amount. However, it would be an easy mistake to make so check here.
assert((ShImm & ~0x1f) == 0 && "Out of range shift amount");
// {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 MCSubtargetInfo &STI) const {
// {17-14} Rn
// {13} 1 == imm12, 0 == Rm
// {12} isAdd
// {11-0} imm12/Rm
const MCOperand &MO = MI.getOperand(OpIdx);
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
uint32_t Binary = getAddrMode2OffsetOpValue(MI, OpIdx + 1, Fixups, STI);
Binary |= Rn << 14;
return Binary;
}
uint32_t ARMMCCodeEmitter::
getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 |= CTX.getRegisterInfo()->getEncodingValue(MO.getReg()); // Rm is bits [3:0]
}
return Binary | (isAdd << 12) | (isReg << 13);
}
uint32_t ARMMCCodeEmitter::
getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// {4} isAdd
// {3-0} Rm
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx+1);
bool isAdd = MO1.getImm() != 0;
return CTX.getRegisterInfo()->getEncodingValue(MO.getReg()) | (isAdd << 4);
}
uint32_t ARMMCCodeEmitter::
getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
return Imm8 | (isAdd << 8) | (isImm << 9);
}
uint32_t ARMMCCodeEmitter::
getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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);
// If The first operand isn't a register, we have a label reference.
if (!MO.isReg()) {
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(ARM::PC); // Rn is PC.
assert(MO.isExpr() && "Unexpected machine operand type!");
const MCExpr *Expr = MO.getExpr();
MCFixupKind Kind = MCFixupKind(ARM::fixup_arm_pcrel_10_unscaled);
Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
++MCNumCPRelocations;
return (Rn << 9) | (1 << 13);
}
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(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 = CTX.getRegisterInfo()->getEncodingValue(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 MCSubtargetInfo &STI) const {
// [SP, #imm]
// {7-0} = imm8
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
assert(MI.getOperand(OpIdx).getReg() == ARM::SP &&
"Unexpected base register!");
// The immediate is already shifted for the implicit zeroes, so no change
// here.
return MO1.getImm() & 0xff;
}
/// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
uint32_t ARMMCCodeEmitter::
getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// [Rn, #imm]
// {7-3} = imm5
// {2-0} = Rn
const MCOperand &MO = MI.getOperand(OpIdx);
const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
unsigned Imm5 = MO1.getImm();
return ((Imm5 & 0x1f) << 3) | Rn;
}
/// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
uint32_t ARMMCCodeEmitter::
getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cp, Fixups, STI);
return (MO.getImm() >> 2);
}
/// getAddrMode5OpValue - Return encoding info for 'reg +/- imm10' operand.
uint32_t ARMMCCodeEmitter::
getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 = CTX.getRegisterInfo()->getEncodingValue(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;
if (isThumb2(STI))
Kind = MCFixupKind(ARM::fixup_t2_pcrel_10);
else
Kind = MCFixupKind(ARM::fixup_arm_pcrel_10);
Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
++MCNumCPRelocations;
} else {
EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
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::
getSORegRegOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// Sub-operands are [reg, reg, imm]. The first register is Rm, the reg to be
// shifted. The second is Rs, the amount to shift by, and the third specifies
// the type of the shift.
//
// {3-0} = Rm.
// {4} = 1
// {6-5} = type
// {11-8} = Rs
// {7} = 0
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 = CTX.getRegisterInfo()->getEncodingValue(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
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;
}
}
Binary |= SBits << 4;
// Encode the shift operation Rs.
// Encode Rs bit[11:8].
assert(ARM_AM::getSORegOffset(MO2.getImm()) == 0);
return Binary | (CTX.getRegisterInfo()->getEncodingValue(Rs) << ARMII::RegRsShift);
}
unsigned ARMMCCodeEmitter::
getSORegImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
// Encode the shift opcode.
unsigned SBits = 0;
// Set shift operand (bit[6:4]).
// LSL - 000
// LSR - 010
// ASR - 100
// ROR - 110
// RRX - 110 and bit[11:8] clear.
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;
case ARM_AM::rrx:
Binary |= 0x60;
return Binary;
}
// Encode shift_imm bit[11:7].
Binary |= SBits << 4;
unsigned Offset = ARM_AM::getSORegOffset(MO1.getImm());
assert(Offset < 32 && "Offset must be in range 0-31!");
return Binary | (Offset << 7);
}
unsigned ARMMCCodeEmitter::
getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) 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 = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
Value <<= 4;
Value |= CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
Value <<= 2;
Value |= MO3.getImm();
return Value;
}
unsigned ARMMCCodeEmitter::
getT2AddrModeImm8OpValue(const MCInst &MI, unsigned OpNum,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO1 = MI.getOperand(OpNum);
const MCOperand &MO2 = MI.getOperand(OpNum+1);
// FIXME: Needs fixup support.
unsigned Value = CTX.getRegisterInfo()->getEncodingValue(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 MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) 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 MCSubtargetInfo &STI) 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 = CTX.getRegisterInfo()->getEncodingValue(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::rrx: // FALLTHROUGH
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 MCSubtargetInfo &STI) 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(v);
uint32_t msb = (32 - countLeadingZeros (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 MCSubtargetInfo &STI) 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 = ARMMCRegisterClasses[ARM::SPRRegClassID].contains(Reg);
bool DPRRegs = ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg);
unsigned Binary = 0;
if (SPRRegs || DPRRegs) {
// VLDM/VSTM
unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(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 = CTX.getRegisterInfo()->getEncodingValue(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 MCSubtargetInfo &STI) const {
const MCOperand &Reg = MI.getOperand(Op);
const MCOperand &Imm = MI.getOperand(Op + 1);
unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(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);
}
/// getAddrMode6OneLane32AddressOpValue - Encode an addrmode6 register number
/// along with the alignment operand for use in VST1 and VLD1 with size 32.
unsigned ARMMCCodeEmitter::
getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &Reg = MI.getOperand(Op);
const MCOperand &Imm = MI.getOperand(Op + 1);
unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
unsigned Align = 0;
switch (Imm.getImm()) {
default: break;
case 8:
case 16:
case 32: // Default '0' value for invalid alignments of 8, 16, 32 bytes.
case 2: Align = 0x00; break;
case 4: 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 MCSubtargetInfo &STI) const {
const MCOperand &Reg = MI.getOperand(Op);
const MCOperand &Imm = MI.getOperand(Op + 1);
unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(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 MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(Op);
if (MO.getReg() == 0) return 0x0D;
return CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
}
unsigned ARMMCCodeEmitter::
getShiftRight8Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
return 8 - MI.getOperand(Op).getImm();
}
unsigned ARMMCCodeEmitter::
getShiftRight16Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
return 16 - MI.getOperand(Op).getImm();
}
unsigned ARMMCCodeEmitter::
getShiftRight32Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
return 32 - MI.getOperand(Op).getImm();
}
unsigned ARMMCCodeEmitter::
getShiftRight64Imm(const MCInst &MI, unsigned Op,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
return 64 - MI.getOperand(Op).getImm();
}
void ARMMCCodeEmitter::
EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// Pseudo instructions don't get encoded.
const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
uint64_t TSFlags = Desc.TSFlags;
if ((TSFlags & ARMII::FormMask) == ARMII::Pseudo)
return;
int Size;
if (Desc.getSize() == 2 || Desc.getSize() == 4)
Size = Desc.getSize();
else
llvm_unreachable("Unexpected instruction size!");
uint32_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
// Thumb 32-bit wide instructions need to emit the high order halfword
// first.
if (isThumb(STI) && 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"