ARMCodeEmitter.cpp revision f17a25c88b892d30c2b41ba7ecdfbdfb2b4be9cc 
1//===-- ARM/ARMCodeEmitter.cpp - Convert ARM code to machine code ---------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the Raul Herbster and is distributed under the
6// University of Illinois Open Source License.  See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains the pass that transforms the ARM machine instructions into
11// relocatable machine code.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "arm-emitter"
16#include "ARMInstrInfo.h"
17#include "ARMSubtarget.h"
18#include "ARMTargetMachine.h"
19#include "ARM.h"
20#include "llvm/PassManager.h"
21#include "llvm/CodeGen/MachineCodeEmitter.h"
22#include "llvm/CodeGen/MachineFunctionPass.h"
23#include "llvm/CodeGen/MachineInstr.h"
24#include "llvm/CodeGen/Passes.h"
25#include "llvm/Function.h"
26#include "llvm/ADT/Statistic.h"
27#include "llvm/Support/Compiler.h"
28using namespace llvm;
29
30STATISTIC(NumEmitted, "Number of machine instructions emitted");
31
32namespace {
33  class VISIBILITY_HIDDEN Emitter : public MachineFunctionPass {
34    const ARMInstrInfo  *II;
35    const TargetData    *TD;
36    TargetMachine       &TM;
37    MachineCodeEmitter  &MCE;
38  public:
39    static char ID;
40    explicit Emitter(TargetMachine &tm, MachineCodeEmitter &mce)
41      : MachineFunctionPass((intptr_t)&ID), II(0), TD(0), TM(tm),
42      MCE(mce) {}
43    Emitter(TargetMachine &tm, MachineCodeEmitter &mce,
44            const ARMInstrInfo &ii, const TargetData &td)
45      : MachineFunctionPass((intptr_t)&ID), II(&ii), TD(&td), TM(tm),
46      MCE(mce) {}
47
48    bool runOnMachineFunction(MachineFunction &MF);
49
50    virtual const char *getPassName() const {
51      return "ARM Machine Code Emitter";
52    }
53
54    void emitInstruction(const MachineInstr &MI);
55
56  private:
57
58  };
59  char Emitter::ID = 0;
60}
61
62/// createARMCodeEmitterPass - Return a pass that emits the collected ARM code
63/// to the specified MCE object.
64FunctionPass *llvm::createARMCodeEmitterPass(ARMTargetMachine &TM,
65                                             MachineCodeEmitter &MCE) {
66  return new Emitter(TM, MCE);
67}
68
69bool Emitter::runOnMachineFunction(MachineFunction &MF) {
70  assert((MF.getTarget().getRelocationModel() != Reloc::Default ||
71          MF.getTarget().getRelocationModel() != Reloc::Static) &&
72         "JIT relocation model must be set to static or default!");
73  II = ((ARMTargetMachine&)MF.getTarget()).getInstrInfo();
74  TD = ((ARMTargetMachine&)MF.getTarget()).getTargetData();
75
76  do {
77    MCE.startFunction(MF);
78    for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
79         MBB != E; ++MBB) {
80      MCE.StartMachineBasicBlock(MBB);
81      for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
82           I != E; ++I)
83        emitInstruction(*I);
84    }
85  } while (MCE.finishFunction(MF));
86
87  return false;
88}
89
90void Emitter::emitInstruction(const MachineInstr &MI) {
91  NumEmitted++;  // Keep track of the # of mi's emitted
92}
93