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Diffstat (limited to 'lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp')
| -rw-r--r-- | lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp | 517 |
1 files changed, 517 insertions, 0 deletions
diff --git a/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp b/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp new file mode 100644 index 0000000000..f2bbd85209 --- /dev/null +++ b/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp @@ -0,0 +1,517 @@ +//=- 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/AArch64BaseInfo.h" +#include "MCTargetDesc/AArch64FixupKinds.h" +#include "MCTargetDesc/AArch64MCExpr.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 &); // DO NOT IMPLEMENT + void operator=(const AArch64MCCodeEmitter &); // DO NOT IMPLEMENT + const MCInstrInfo &MCII; + const MCSubtargetInfo &STI; + MCContext &Ctx; + +public: + AArch64MCCodeEmitter(const MCInstrInfo &mcii, const MCSubtargetInfo &sti, + MCContext &ctx) + : MCII(mcii), STI(sti), 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; + + unsigned fixFCMPImm(const MCInst &MI, unsigned EncodedValue) 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: { + 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: { + 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: { + 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:{ + 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: { + 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); +} + +unsigned AArch64MCCodeEmitter::fixFCMPImm(const MCInst &MI, + unsigned EncodedValue) const { + // For FCMP[E] Rn, #0.0, the Rm field has a canonical representation + // with 0s, but is architecturally ignored + EncodedValue &= ~0x1f0000u; + + return EncodedValue; +} + +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(MCII, STI, 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" |