llvm-project/llvm/lib/Target/Lanai/MCTargetDesc/LanaiMCCodeEmitter.cpp
Dmitri Gribenko 2f66316c96 Include what you use in LanaiMCCodeEmitter.cpp
LanaiMCCodeEmitter.cpp was not using any APIs from Lanai.h, and was only
including it for transitive dependencies.  Doing so is problematic from
include-what-you-use perspective, but it is also a layering issue (it
creates a dependency cycle between the primary Lanai target library and
the MCTargetDesc library).

llvm-svn: 362394
2019-06-03 12:42:48 +00:00

311 lines
11 KiB
C++

//===-- LanaiMCCodeEmitter.cpp - Convert Lanai code to machine code -------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements the LanaiMCCodeEmitter class.
//
//===----------------------------------------------------------------------===//
#include "LanaiAluCode.h"
#include "MCTargetDesc/LanaiBaseInfo.h"
#include "MCTargetDesc/LanaiFixupKinds.h"
#include "MCTargetDesc/LanaiMCExpr.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdint>
#define DEBUG_TYPE "mccodeemitter"
STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
namespace llvm {
namespace {
class LanaiMCCodeEmitter : public MCCodeEmitter {
public:
LanaiMCCodeEmitter(const MCInstrInfo &MCII, MCContext &C) {}
LanaiMCCodeEmitter(const LanaiMCCodeEmitter &) = delete;
void operator=(const LanaiMCCodeEmitter &) = delete;
~LanaiMCCodeEmitter() override = default;
// The functions below are called by TableGen generated functions for getting
// the binary encoding of instructions/opereands.
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
uint64_t getBinaryCodeForInstr(const MCInst &Inst,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
// getMachineOpValue - Return binary encoding of operand. If the machine
// operand requires relocation, record the relocation and return zero.
unsigned getMachineOpValue(const MCInst &Inst, const MCOperand &MCOp,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
unsigned getRiMemoryOpValue(const MCInst &Inst, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
unsigned getRrMemoryOpValue(const MCInst &Inst, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
unsigned getSplsOpValue(const MCInst &Inst, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
unsigned getBranchTargetOpValue(const MCInst &Inst, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const;
void encodeInstruction(const MCInst &Inst, raw_ostream &Ostream,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const override;
unsigned adjustPqBitsRmAndRrm(const MCInst &Inst, unsigned Value,
const MCSubtargetInfo &STI) const;
unsigned adjustPqBitsSpls(const MCInst &Inst, unsigned Value,
const MCSubtargetInfo &STI) const;
};
} // end anonymous namespace
static Lanai::Fixups FixupKind(const MCExpr *Expr) {
if (isa<MCSymbolRefExpr>(Expr))
return Lanai::FIXUP_LANAI_21;
if (const LanaiMCExpr *McExpr = dyn_cast<LanaiMCExpr>(Expr)) {
LanaiMCExpr::VariantKind ExprKind = McExpr->getKind();
switch (ExprKind) {
case LanaiMCExpr::VK_Lanai_None:
return Lanai::FIXUP_LANAI_21;
case LanaiMCExpr::VK_Lanai_ABS_HI:
return Lanai::FIXUP_LANAI_HI16;
case LanaiMCExpr::VK_Lanai_ABS_LO:
return Lanai::FIXUP_LANAI_LO16;
}
}
return Lanai::Fixups(0);
}
// getMachineOpValue - Return binary encoding of operand. If the machine
// operand requires relocation, record the relocation and return zero.
unsigned LanaiMCCodeEmitter::getMachineOpValue(
const MCInst &Inst, const MCOperand &MCOp, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
if (MCOp.isReg())
return getLanaiRegisterNumbering(MCOp.getReg());
if (MCOp.isImm())
return static_cast<unsigned>(MCOp.getImm());
// MCOp must be an expression
assert(MCOp.isExpr());
const MCExpr *Expr = MCOp.getExpr();
// Extract the symbolic reference side of a binary expression.
if (Expr->getKind() == MCExpr::Binary) {
const MCBinaryExpr *BinaryExpr = static_cast<const MCBinaryExpr *>(Expr);
Expr = BinaryExpr->getLHS();
}
assert(isa<LanaiMCExpr>(Expr) || Expr->getKind() == MCExpr::SymbolRef);
// Push fixup (all info is contained within)
Fixups.push_back(
MCFixup::create(0, MCOp.getExpr(), MCFixupKind(FixupKind(Expr))));
return 0;
}
// Helper function to adjust P and Q bits on load and store instructions.
static unsigned adjustPqBits(const MCInst &Inst, unsigned Value,
unsigned PBitShift, unsigned QBitShift) {
const MCOperand AluOp = Inst.getOperand(3);
unsigned AluCode = AluOp.getImm();
// Set the P bit to one iff the immediate is nonzero and not a post-op
// instruction.
const MCOperand Op2 = Inst.getOperand(2);
Value &= ~(1 << PBitShift);
if (!LPAC::isPostOp(AluCode) &&
((Op2.isImm() && Op2.getImm() != 0) ||
(Op2.isReg() && Op2.getReg() != Lanai::R0) || (Op2.isExpr())))
Value |= (1 << PBitShift);
// Set the Q bit to one iff it is a post- or pre-op instruction.
assert(Inst.getOperand(0).isReg() && Inst.getOperand(1).isReg() &&
"Expected register operand.");
Value &= ~(1 << QBitShift);
if (LPAC::modifiesOp(AluCode) && ((Op2.isImm() && Op2.getImm() != 0) ||
(Op2.isReg() && Op2.getReg() != Lanai::R0)))
Value |= (1 << QBitShift);
return Value;
}
unsigned
LanaiMCCodeEmitter::adjustPqBitsRmAndRrm(const MCInst &Inst, unsigned Value,
const MCSubtargetInfo &STI) const {
return adjustPqBits(Inst, Value, 17, 16);
}
unsigned
LanaiMCCodeEmitter::adjustPqBitsSpls(const MCInst &Inst, unsigned Value,
const MCSubtargetInfo &STI) const {
return adjustPqBits(Inst, Value, 11, 10);
}
void LanaiMCCodeEmitter::encodeInstruction(
const MCInst &Inst, raw_ostream &Ostream, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
// Get instruction encoding and emit it
unsigned Value = getBinaryCodeForInstr(Inst, Fixups, SubtargetInfo);
++MCNumEmitted; // Keep track of the number of emitted insns.
// Emit bytes in big-endian
for (int i = (4 - 1) * 8; i >= 0; i -= 8)
Ostream << static_cast<char>((Value >> i) & 0xff);
}
// Encode Lanai Memory Operand
unsigned LanaiMCCodeEmitter::getRiMemoryOpValue(
const MCInst &Inst, unsigned OpNo, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
unsigned Encoding;
const MCOperand Op1 = Inst.getOperand(OpNo + 0);
const MCOperand Op2 = Inst.getOperand(OpNo + 1);
const MCOperand AluOp = Inst.getOperand(OpNo + 2);
assert(Op1.isReg() && "First operand is not register.");
assert((Op2.isImm() || Op2.isExpr()) &&
"Second operand is neither an immediate nor an expression.");
assert((LPAC::getAluOp(AluOp.getImm()) == LPAC::ADD) &&
"Register immediate only supports addition operator");
Encoding = (getLanaiRegisterNumbering(Op1.getReg()) << 18);
if (Op2.isImm()) {
assert(isInt<16>(Op2.getImm()) &&
"Constant value truncated (limited to 16-bit)");
Encoding |= (Op2.getImm() & 0xffff);
if (Op2.getImm() != 0) {
if (LPAC::isPreOp(AluOp.getImm()))
Encoding |= (0x3 << 16);
if (LPAC::isPostOp(AluOp.getImm()))
Encoding |= (0x1 << 16);
}
} else
getMachineOpValue(Inst, Op2, Fixups, SubtargetInfo);
return Encoding;
}
unsigned LanaiMCCodeEmitter::getRrMemoryOpValue(
const MCInst &Inst, unsigned OpNo, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
unsigned Encoding;
const MCOperand Op1 = Inst.getOperand(OpNo + 0);
const MCOperand Op2 = Inst.getOperand(OpNo + 1);
const MCOperand AluMCOp = Inst.getOperand(OpNo + 2);
assert(Op1.isReg() && "First operand is not register.");
Encoding = (getLanaiRegisterNumbering(Op1.getReg()) << 15);
assert(Op2.isReg() && "Second operand is not register.");
Encoding |= (getLanaiRegisterNumbering(Op2.getReg()) << 10);
assert(AluMCOp.isImm() && "Third operator is not immediate.");
// Set BBB
unsigned AluOp = AluMCOp.getImm();
Encoding |= LPAC::encodeLanaiAluCode(AluOp) << 5;
// Set P and Q
if (LPAC::isPreOp(AluOp))
Encoding |= (0x3 << 8);
if (LPAC::isPostOp(AluOp))
Encoding |= (0x1 << 8);
// Set JJJJ
switch (LPAC::getAluOp(AluOp)) {
case LPAC::SHL:
case LPAC::SRL:
Encoding |= 0x10;
break;
case LPAC::SRA:
Encoding |= 0x18;
break;
default:
break;
}
return Encoding;
}
unsigned
LanaiMCCodeEmitter::getSplsOpValue(const MCInst &Inst, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
unsigned Encoding;
const MCOperand Op1 = Inst.getOperand(OpNo + 0);
const MCOperand Op2 = Inst.getOperand(OpNo + 1);
const MCOperand AluOp = Inst.getOperand(OpNo + 2);
assert(Op1.isReg() && "First operand is not register.");
assert((Op2.isImm() || Op2.isExpr()) &&
"Second operand is neither an immediate nor an expression.");
assert((LPAC::getAluOp(AluOp.getImm()) == LPAC::ADD) &&
"Register immediate only supports addition operator");
Encoding = (getLanaiRegisterNumbering(Op1.getReg()) << 12);
if (Op2.isImm()) {
assert(isInt<10>(Op2.getImm()) &&
"Constant value truncated (limited to 10-bit)");
Encoding |= (Op2.getImm() & 0x3ff);
if (Op2.getImm() != 0) {
if (LPAC::isPreOp(AluOp.getImm()))
Encoding |= (0x3 << 10);
if (LPAC::isPostOp(AluOp.getImm()))
Encoding |= (0x1 << 10);
}
} else
getMachineOpValue(Inst, Op2, Fixups, SubtargetInfo);
return Encoding;
}
unsigned LanaiMCCodeEmitter::getBranchTargetOpValue(
const MCInst &Inst, unsigned OpNo, SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &SubtargetInfo) const {
const MCOperand &MCOp = Inst.getOperand(OpNo);
if (MCOp.isReg() || MCOp.isImm())
return getMachineOpValue(Inst, MCOp, Fixups, SubtargetInfo);
Fixups.push_back(MCFixup::create(
0, MCOp.getExpr(), static_cast<MCFixupKind>(Lanai::FIXUP_LANAI_25)));
return 0;
}
#include "LanaiGenMCCodeEmitter.inc"
} // end namespace llvm
llvm::MCCodeEmitter *
llvm::createLanaiMCCodeEmitter(const MCInstrInfo &InstrInfo,
const MCRegisterInfo & /*MRI*/,
MCContext &context) {
return new LanaiMCCodeEmitter(InstrInfo, context);
}