llvm-project/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp

511 lines
18 KiB
C++

//=- AArch64/AArch64MCCodeEmitter.cpp - Convert AArch64 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 AArch64MCCodeEmitter class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "mccodeemitter"
#include "MCTargetDesc/AArch64FixupKinds.h"
#include "MCTargetDesc/AArch64MCExpr.h"
#include "MCTargetDesc/AArch64MCTargetDesc.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.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;
namespace {
class AArch64MCCodeEmitter : public MCCodeEmitter {
AArch64MCCodeEmitter(const AArch64MCCodeEmitter &) LLVM_DELETED_FUNCTION;
void operator=(const AArch64MCCodeEmitter &) LLVM_DELETED_FUNCTION;
MCContext &Ctx;
public:
AArch64MCCodeEmitter(MCContext &ctx) : Ctx(ctx) {}
~AArch64MCCodeEmitter() {}
unsigned getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getAdrpLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
template<int MemSize>
unsigned getOffsetUImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
return getOffsetUImm12OpValue(MI, OpIdx, Fixups, MemSize);
}
unsigned getOffsetUImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
int MemSize) const;
unsigned getBitfield32LSLOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getBitfield64LSLOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
// Labels are handled mostly the same way: a symbol is needed, and
// just gets some fixup attached.
template<AArch64::Fixups fixupDesired>
unsigned getLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getLoadLitLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getAddressWithFixup(const MCOperand &MO,
unsigned FixupKind,
SmallVectorImpl<MCFixup> &Fixups) const;
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
uint64_t 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;
void EmitByte(unsigned char C, raw_ostream &OS) const {
OS << (char)C;
}
void EmitInstruction(uint32_t Val, raw_ostream &OS) const {
// Output the constant in little endian byte order.
for (unsigned i = 0; i != 4; ++i) {
EmitByte(Val & 0xff, OS);
Val >>= 8;
}
}
void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups) const;
template<int hasRs, int hasRt2> unsigned
fixLoadStoreExclusive(const MCInst &MI, unsigned EncodedValue) const;
unsigned fixMOVZ(const MCInst &MI, unsigned EncodedValue) const;
unsigned fixMulHigh(const MCInst &MI, unsigned EncodedValue) const;
};
} // end anonymous namespace
unsigned AArch64MCCodeEmitter::getAddressWithFixup(const MCOperand &MO,
unsigned FixupKind,
SmallVectorImpl<MCFixup> &Fixups) const {
if (!MO.isExpr()) {
// This can occur for manually decoded or constructed MCInsts, but neither
// the assembly-parser nor instruction selection will currently produce an
// MCInst that's not a symbol reference.
assert(MO.isImm() && "Unexpected address requested");
return MO.getImm();
}
const MCExpr *Expr = MO.getExpr();
MCFixupKind Kind = MCFixupKind(FixupKind);
Fixups.push_back(MCFixup::Create(0, Expr, Kind));
return 0;
}
unsigned AArch64MCCodeEmitter::
getOffsetUImm12OpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups,
int MemSize) const {
const MCOperand &ImmOp = MI.getOperand(OpIdx);
if (ImmOp.isImm())
return ImmOp.getImm();
assert(ImmOp.isExpr() && "Unexpected operand type");
const AArch64MCExpr *Expr = cast<AArch64MCExpr>(ImmOp.getExpr());
unsigned FixupKind;
switch (Expr->getKind()) {
default: llvm_unreachable("Unexpected operand modifier");
case AArch64MCExpr::VK_AARCH64_LO12: {
static const unsigned FixupsBySize[] = { AArch64::fixup_a64_ldst8_lo12,
AArch64::fixup_a64_ldst16_lo12,
AArch64::fixup_a64_ldst32_lo12,
AArch64::fixup_a64_ldst64_lo12,
AArch64::fixup_a64_ldst128_lo12 };
assert(MemSize <= 16 && "Invalid fixup for operation");
FixupKind = FixupsBySize[Log2_32(MemSize)];
break;
}
case AArch64MCExpr::VK_AARCH64_GOT_LO12:
assert(MemSize == 8 && "Invalid fixup for operation");
FixupKind = AArch64::fixup_a64_ld64_got_lo12_nc;
break;
case AArch64MCExpr::VK_AARCH64_DTPREL_LO12: {
static const unsigned FixupsBySize[] = {
AArch64::fixup_a64_ldst8_dtprel_lo12,
AArch64::fixup_a64_ldst16_dtprel_lo12,
AArch64::fixup_a64_ldst32_dtprel_lo12,
AArch64::fixup_a64_ldst64_dtprel_lo12
};
assert(MemSize <= 8 && "Invalid fixup for operation");
FixupKind = FixupsBySize[Log2_32(MemSize)];
break;
}
case AArch64MCExpr::VK_AARCH64_DTPREL_LO12_NC: {
static const unsigned FixupsBySize[] = {
AArch64::fixup_a64_ldst8_dtprel_lo12_nc,
AArch64::fixup_a64_ldst16_dtprel_lo12_nc,
AArch64::fixup_a64_ldst32_dtprel_lo12_nc,
AArch64::fixup_a64_ldst64_dtprel_lo12_nc
};
assert(MemSize <= 8 && "Invalid fixup for operation");
FixupKind = FixupsBySize[Log2_32(MemSize)];
break;
}
case AArch64MCExpr::VK_AARCH64_GOTTPREL_LO12:
assert(MemSize == 8 && "Invalid fixup for operation");
FixupKind = AArch64::fixup_a64_ld64_gottprel_lo12_nc;
break;
case AArch64MCExpr::VK_AARCH64_TPREL_LO12:{
static const unsigned FixupsBySize[] = {
AArch64::fixup_a64_ldst8_tprel_lo12,
AArch64::fixup_a64_ldst16_tprel_lo12,
AArch64::fixup_a64_ldst32_tprel_lo12,
AArch64::fixup_a64_ldst64_tprel_lo12
};
assert(MemSize <= 8 && "Invalid fixup for operation");
FixupKind = FixupsBySize[Log2_32(MemSize)];
break;
}
case AArch64MCExpr::VK_AARCH64_TPREL_LO12_NC: {
static const unsigned FixupsBySize[] = {
AArch64::fixup_a64_ldst8_tprel_lo12_nc,
AArch64::fixup_a64_ldst16_tprel_lo12_nc,
AArch64::fixup_a64_ldst32_tprel_lo12_nc,
AArch64::fixup_a64_ldst64_tprel_lo12_nc
};
assert(MemSize <= 8 && "Invalid fixup for operation");
FixupKind = FixupsBySize[Log2_32(MemSize)];
break;
}
case AArch64MCExpr::VK_AARCH64_TLSDESC_LO12:
assert(MemSize == 8 && "Invalid fixup for operation");
FixupKind = AArch64::fixup_a64_tlsdesc_ld64_lo12_nc;
break;
}
return getAddressWithFixup(ImmOp, FixupKind, Fixups);
}
unsigned
AArch64MCCodeEmitter::getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isImm())
return static_cast<unsigned>(MO.getImm());
assert(MO.isExpr());
unsigned FixupKind = 0;
switch(cast<AArch64MCExpr>(MO.getExpr())->getKind()) {
default: llvm_unreachable("Invalid expression modifier");
case AArch64MCExpr::VK_AARCH64_LO12:
FixupKind = AArch64::fixup_a64_add_lo12; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_HI12:
FixupKind = AArch64::fixup_a64_add_dtprel_hi12; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_LO12:
FixupKind = AArch64::fixup_a64_add_dtprel_lo12; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_LO12_NC:
FixupKind = AArch64::fixup_a64_add_dtprel_lo12_nc; break;
case AArch64MCExpr::VK_AARCH64_TPREL_HI12:
FixupKind = AArch64::fixup_a64_add_tprel_hi12; break;
case AArch64MCExpr::VK_AARCH64_TPREL_LO12:
FixupKind = AArch64::fixup_a64_add_tprel_lo12; break;
case AArch64MCExpr::VK_AARCH64_TPREL_LO12_NC:
FixupKind = AArch64::fixup_a64_add_tprel_lo12_nc; break;
case AArch64MCExpr::VK_AARCH64_TLSDESC_LO12:
FixupKind = AArch64::fixup_a64_tlsdesc_add_lo12_nc; break;
}
return getAddressWithFixup(MO, FixupKind, Fixups);
}
unsigned
AArch64MCCodeEmitter::getAdrpLabelOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isImm())
return static_cast<unsigned>(MO.getImm());
assert(MO.isExpr());
unsigned Modifier = AArch64MCExpr::VK_AARCH64_None;
if (const AArch64MCExpr *Expr = dyn_cast<AArch64MCExpr>(MO.getExpr()))
Modifier = Expr->getKind();
unsigned FixupKind = 0;
switch(Modifier) {
case AArch64MCExpr::VK_AARCH64_None:
FixupKind = AArch64::fixup_a64_adr_prel_page;
break;
case AArch64MCExpr::VK_AARCH64_GOT:
FixupKind = AArch64::fixup_a64_adr_prel_got_page;
break;
case AArch64MCExpr::VK_AARCH64_GOTTPREL:
FixupKind = AArch64::fixup_a64_adr_gottprel_page;
break;
case AArch64MCExpr::VK_AARCH64_TLSDESC:
FixupKind = AArch64::fixup_a64_tlsdesc_adr_page;
break;
default:
llvm_unreachable("Unknown symbol reference kind for ADRP instruction");
}
return getAddressWithFixup(MO, FixupKind, Fixups);
}
unsigned
AArch64MCCodeEmitter::getBitfield32LSLOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
assert(MO.isImm() && "Only immediate expected for shift");
return ((32 - MO.getImm()) & 0x1f) | (31 - MO.getImm()) << 6;
}
unsigned
AArch64MCCodeEmitter::getBitfield64LSLOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
assert(MO.isImm() && "Only immediate expected for shift");
return ((64 - MO.getImm()) & 0x3f) | (63 - MO.getImm()) << 6;
}
template<AArch64::Fixups fixupDesired> unsigned
AArch64MCCodeEmitter::getLabelOpValue(const MCInst &MI,
unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isExpr())
return getAddressWithFixup(MO, fixupDesired, Fixups);
assert(MO.isImm());
return MO.getImm();
}
unsigned
AArch64MCCodeEmitter::getLoadLitLabelOpValue(const MCInst &MI,
unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpIdx);
if (MO.isImm())
return MO.getImm();
assert(MO.isExpr());
unsigned FixupKind;
if (isa<AArch64MCExpr>(MO.getExpr())) {
assert(dyn_cast<AArch64MCExpr>(MO.getExpr())->getKind()
== AArch64MCExpr::VK_AARCH64_GOTTPREL
&& "Invalid symbol modifier for literal load");
FixupKind = AArch64::fixup_a64_ld_gottprel_prel19;
} else {
FixupKind = AArch64::fixup_a64_ld_prel;
}
return getAddressWithFixup(MO, FixupKind, Fixups);
}
unsigned
AArch64MCCodeEmitter::getMachineOpValue(const MCInst &MI,
const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups) const {
if (MO.isReg()) {
return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
} else if (MO.isImm()) {
return static_cast<unsigned>(MO.getImm());
}
llvm_unreachable("Unable to encode MCOperand!");
return 0;
}
unsigned
AArch64MCCodeEmitter::getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &UImm16MO = MI.getOperand(OpIdx);
const MCOperand &ShiftMO = MI.getOperand(OpIdx + 1);
unsigned Result = static_cast<unsigned>(ShiftMO.getImm()) << 16;
if (UImm16MO.isImm()) {
Result |= UImm16MO.getImm();
return Result;
}
const AArch64MCExpr *A64E = cast<AArch64MCExpr>(UImm16MO.getExpr());
AArch64::Fixups requestedFixup;
switch (A64E->getKind()) {
default: llvm_unreachable("unexpected expression modifier");
case AArch64MCExpr::VK_AARCH64_ABS_G0:
requestedFixup = AArch64::fixup_a64_movw_uabs_g0; break;
case AArch64MCExpr::VK_AARCH64_ABS_G0_NC:
requestedFixup = AArch64::fixup_a64_movw_uabs_g0_nc; break;
case AArch64MCExpr::VK_AARCH64_ABS_G1:
requestedFixup = AArch64::fixup_a64_movw_uabs_g1; break;
case AArch64MCExpr::VK_AARCH64_ABS_G1_NC:
requestedFixup = AArch64::fixup_a64_movw_uabs_g1_nc; break;
case AArch64MCExpr::VK_AARCH64_ABS_G2:
requestedFixup = AArch64::fixup_a64_movw_uabs_g2; break;
case AArch64MCExpr::VK_AARCH64_ABS_G2_NC:
requestedFixup = AArch64::fixup_a64_movw_uabs_g2_nc; break;
case AArch64MCExpr::VK_AARCH64_ABS_G3:
requestedFixup = AArch64::fixup_a64_movw_uabs_g3; break;
case AArch64MCExpr::VK_AARCH64_SABS_G0:
requestedFixup = AArch64::fixup_a64_movw_sabs_g0; break;
case AArch64MCExpr::VK_AARCH64_SABS_G1:
requestedFixup = AArch64::fixup_a64_movw_sabs_g1; break;
case AArch64MCExpr::VK_AARCH64_SABS_G2:
requestedFixup = AArch64::fixup_a64_movw_sabs_g2; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_G2:
requestedFixup = AArch64::fixup_a64_movw_dtprel_g2; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_G1:
requestedFixup = AArch64::fixup_a64_movw_dtprel_g1; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_G1_NC:
requestedFixup = AArch64::fixup_a64_movw_dtprel_g1_nc; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_G0:
requestedFixup = AArch64::fixup_a64_movw_dtprel_g0; break;
case AArch64MCExpr::VK_AARCH64_DTPREL_G0_NC:
requestedFixup = AArch64::fixup_a64_movw_dtprel_g0_nc; break;
case AArch64MCExpr::VK_AARCH64_GOTTPREL_G1:
requestedFixup = AArch64::fixup_a64_movw_gottprel_g1; break;
case AArch64MCExpr::VK_AARCH64_GOTTPREL_G0_NC:
requestedFixup = AArch64::fixup_a64_movw_gottprel_g0_nc; break;
case AArch64MCExpr::VK_AARCH64_TPREL_G2:
requestedFixup = AArch64::fixup_a64_movw_tprel_g2; break;
case AArch64MCExpr::VK_AARCH64_TPREL_G1:
requestedFixup = AArch64::fixup_a64_movw_tprel_g1; break;
case AArch64MCExpr::VK_AARCH64_TPREL_G1_NC:
requestedFixup = AArch64::fixup_a64_movw_tprel_g1_nc; break;
case AArch64MCExpr::VK_AARCH64_TPREL_G0:
requestedFixup = AArch64::fixup_a64_movw_tprel_g0; break;
case AArch64MCExpr::VK_AARCH64_TPREL_G0_NC:
requestedFixup = AArch64::fixup_a64_movw_tprel_g0_nc; break;
}
return Result | getAddressWithFixup(UImm16MO, requestedFixup, Fixups);
}
template<int hasRs, int hasRt2> unsigned
AArch64MCCodeEmitter::fixLoadStoreExclusive(const MCInst &MI,
unsigned EncodedValue) const {
if (!hasRs) EncodedValue |= 0x001F0000;
if (!hasRt2) EncodedValue |= 0x00007C00;
return EncodedValue;
}
unsigned
AArch64MCCodeEmitter::fixMOVZ(const MCInst &MI, unsigned EncodedValue) const {
// If one of the signed fixup kinds is applied to a MOVZ instruction, the
// eventual result could be either a MOVZ or a MOVN. It's the MCCodeEmitter's
// job to ensure that any bits possibly affected by this are 0. This means we
// must zero out bit 30 (essentially emitting a MOVN).
MCOperand UImm16MO = MI.getOperand(1);
// Nothing to do if there's no fixup.
if (UImm16MO.isImm())
return EncodedValue;
const AArch64MCExpr *A64E = cast<AArch64MCExpr>(UImm16MO.getExpr());
switch (A64E->getKind()) {
case AArch64MCExpr::VK_AARCH64_SABS_G0:
case AArch64MCExpr::VK_AARCH64_SABS_G1:
case AArch64MCExpr::VK_AARCH64_SABS_G2:
case AArch64MCExpr::VK_AARCH64_DTPREL_G2:
case AArch64MCExpr::VK_AARCH64_DTPREL_G1:
case AArch64MCExpr::VK_AARCH64_DTPREL_G0:
case AArch64MCExpr::VK_AARCH64_GOTTPREL_G1:
case AArch64MCExpr::VK_AARCH64_TPREL_G2:
case AArch64MCExpr::VK_AARCH64_TPREL_G1:
case AArch64MCExpr::VK_AARCH64_TPREL_G0:
return EncodedValue & ~(1u << 30);
default:
// Nothing to do for an unsigned fixup.
return EncodedValue;
}
llvm_unreachable("Should have returned by now");
}
unsigned
AArch64MCCodeEmitter::fixMulHigh(const MCInst &MI,
unsigned EncodedValue) const {
// The Ra field of SMULH and UMULH is unused: it should be assembled as 31
// (i.e. all bits 1) but is ignored by the processor.
EncodedValue |= 0x1f << 10;
return EncodedValue;
}
MCCodeEmitter *llvm::createAArch64MCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
const MCSubtargetInfo &STI,
MCContext &Ctx) {
return new AArch64MCCodeEmitter(Ctx);
}
void AArch64MCCodeEmitter::
EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups) const {
if (MI.getOpcode() == AArch64::TLSDESCCALL) {
// This is a directive which applies an R_AARCH64_TLSDESC_CALL to the
// following (BLR) instruction. It doesn't emit any code itself so it
// doesn't go through the normal TableGenerated channels.
MCFixupKind Fixup = MCFixupKind(AArch64::fixup_a64_tlsdesc_call);
const MCExpr *Expr;
Expr = AArch64MCExpr::CreateTLSDesc(MI.getOperand(0).getExpr(), Ctx);
Fixups.push_back(MCFixup::Create(0, Expr, Fixup));
return;
}
uint32_t Binary = getBinaryCodeForInstr(MI, Fixups);
EmitInstruction(Binary, OS);
}
#include "AArch64GenMCCodeEmitter.inc"