AMDGPUMCInstLower.cpp revision 263508 
1//===- AMDGPUMCInstLower.cpp - Lower AMDGPU MachineInstr to an MCInst -----===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10/// \file
11/// \brief Code to lower AMDGPU MachineInstrs to their corresponding MCInst.
12//
13//===----------------------------------------------------------------------===//
14//
15
16#include "AMDGPUMCInstLower.h"
17#include "AMDGPUAsmPrinter.h"
18#include "InstPrinter/AMDGPUInstPrinter.h"
19#include "R600InstrInfo.h"
20#include "llvm/CodeGen/MachineBasicBlock.h"
21#include "llvm/CodeGen/MachineInstr.h"
22#include "llvm/IR/Constants.h"
23#include "llvm/MC/MCCodeEmitter.h"
24#include "llvm/MC/MCExpr.h"
25#include "llvm/MC/MCInst.h"
26#include "llvm/MC/MCObjectStreamer.h"
27#include "llvm/MC/MCStreamer.h"
28#include "llvm/Support/ErrorHandling.h"
29#include "llvm/Support/Format.h"
30#include <algorithm>
31
32using namespace llvm;
33
34AMDGPUMCInstLower::AMDGPUMCInstLower(MCContext &ctx):
35  Ctx(ctx)
36{ }
37
38void AMDGPUMCInstLower::lower(const MachineInstr *MI, MCInst &OutMI) const {
39  OutMI.setOpcode(MI->getOpcode());
40
41  for (unsigned i = 0, e = MI->getNumExplicitOperands(); i != e; ++i) {
42    const MachineOperand &MO = MI->getOperand(i);
43
44    MCOperand MCOp;
45    switch (MO.getType()) {
46    default:
47      llvm_unreachable("unknown operand type");
48    case MachineOperand::MO_FPImmediate: {
49      const APFloat &FloatValue = MO.getFPImm()->getValueAPF();
50      assert(&FloatValue.getSemantics() == &APFloat::IEEEsingle &&
51             "Only floating point immediates are supported at the moment.");
52      MCOp = MCOperand::CreateFPImm(FloatValue.convertToFloat());
53      break;
54    }
55    case MachineOperand::MO_Immediate:
56      MCOp = MCOperand::CreateImm(MO.getImm());
57      break;
58    case MachineOperand::MO_Register:
59      MCOp = MCOperand::CreateReg(MO.getReg());
60      break;
61    case MachineOperand::MO_MachineBasicBlock:
62      MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
63                                   MO.getMBB()->getSymbol(), Ctx));
64    }
65    OutMI.addOperand(MCOp);
66  }
67}
68
69void AMDGPUAsmPrinter::EmitInstruction(const MachineInstr *MI) {
70  AMDGPUMCInstLower MCInstLowering(OutContext);
71
72  if (MI->isBundle()) {
73    const MachineBasicBlock *MBB = MI->getParent();
74    MachineBasicBlock::const_instr_iterator I = MI;
75    ++I;
76    while (I != MBB->end() && I->isInsideBundle()) {
77      EmitInstruction(I);
78      ++I;
79    }
80  } else {
81    MCInst TmpInst;
82    MCInstLowering.lower(MI, TmpInst);
83    OutStreamer.EmitInstruction(TmpInst);
84
85    if (DisasmEnabled) {
86      // Disassemble instruction/operands to text.
87      DisasmLines.resize(DisasmLines.size() + 1);
88      std::string &DisasmLine = DisasmLines.back();
89      raw_string_ostream DisasmStream(DisasmLine);
90
91      AMDGPUInstPrinter InstPrinter(*TM.getMCAsmInfo(), *TM.getInstrInfo(),
92                                    *TM.getRegisterInfo());
93      InstPrinter.printInst(&TmpInst, DisasmStream, StringRef());
94
95      // Disassemble instruction/operands to hex representation.
96      SmallVector<MCFixup, 4> Fixups;
97      SmallVector<char, 16> CodeBytes;
98      raw_svector_ostream CodeStream(CodeBytes);
99
100      MCObjectStreamer &ObjStreamer = (MCObjectStreamer &)OutStreamer;
101      MCCodeEmitter &InstEmitter = ObjStreamer.getAssembler().getEmitter();
102      InstEmitter.EncodeInstruction(TmpInst, CodeStream, Fixups);
103      CodeStream.flush();
104
105      HexLines.resize(HexLines.size() + 1);
106      std::string &HexLine = HexLines.back();
107      raw_string_ostream HexStream(HexLine);
108
109      for (size_t i = 0; i < CodeBytes.size(); i += 4) {
110        unsigned int CodeDWord = *(unsigned int *)&CodeBytes[i];
111        HexStream << format("%s%08X", (i > 0 ? " " : ""), CodeDWord);
112      }
113
114      DisasmStream.flush();
115      DisasmLineMaxLen = std::max(DisasmLineMaxLen, DisasmLine.size());
116    }
117  }
118}
119