1 //===-- Alpha/AlphaCodeEmitter.cpp - Convert Alpha code to machine code ---===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the pass that transforms the Alpha machine instructions
11 // into relocatable machine code.
13 //===----------------------------------------------------------------------===//
15 #include "AlphaTargetMachine.h"
16 #include "AlphaRelocations.h"
18 #include "llvm/PassManager.h"
19 #include "llvm/CodeGen/MachineCodeEmitter.h"
20 #include "llvm/CodeGen/MachineFunctionPass.h"
21 #include "llvm/CodeGen/MachineInstr.h"
22 #include "llvm/CodeGen/Passes.h"
23 #include "llvm/Function.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/ADT/Statistic.h"
31 NumEmitted("alpha-emitter", "Number of machine instructions emitted");
35 class AlphaCodeEmitter : public MachineFunctionPass {
36 const AlphaInstrInfo *II;
37 MachineCodeEmitter &MCE;
38 std::vector<std::pair<MachineBasicBlock *, unsigned*> > BBRefs;
40 /// getMachineOpValue - evaluates the MachineOperand of a given MachineInstr
42 int getMachineOpValue(MachineInstr &MI, MachineOperand &MO);
45 explicit AlphaCodeEmitter(MachineCodeEmitter &mce) : II(0), MCE(mce) {}
46 AlphaCodeEmitter(MachineCodeEmitter &mce, const AlphaInstrInfo& ii)
47 : II(&ii), MCE(mce) {}
49 bool runOnMachineFunction(MachineFunction &MF);
51 virtual const char *getPassName() const {
52 return "Alpha Machine Code Emitter";
55 void emitInstruction(const MachineInstr &MI);
57 /// getBinaryCodeForInstr - This function, generated by the
58 /// CodeEmitterGenerator using TableGen, produces the binary encoding for
59 /// machine instructions.
61 unsigned getBinaryCodeForInstr(MachineInstr &MI);
64 void emitBasicBlock(MachineBasicBlock &MBB);
69 /// createAlphaCodeEmitterPass - Return a pass that emits the collected Alpha code
70 /// to the specified MCE object.
71 FunctionPass *llvm::createAlphaCodeEmitterPass(MachineCodeEmitter &MCE) {
72 return new AlphaCodeEmitter(MCE);
75 bool AlphaCodeEmitter::runOnMachineFunction(MachineFunction &MF) {
76 II = ((AlphaTargetMachine&)MF.getTarget()).getInstrInfo();
81 MCE.startFunction(MF);
82 for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
84 } while (MCE.finishFunction(MF));
86 // Resolve all forward branches now...
87 for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) {
89 (unsigned*)MCE.getMachineBasicBlockAddress(BBRefs[i].first);
90 unsigned* Ref = (unsigned*)BBRefs[i].second;
91 intptr_t BranchTargetDisp =
92 (((unsigned char*)Location - (unsigned char*)Ref) >> 2) - 1;
93 DEBUG(std::cerr << "Fixup @ " << (void*)Ref << " to " << (void*)Location
94 << " Disp " << BranchTargetDisp
95 << " using " << (BranchTargetDisp & ((1 << 22)-1)) << "\n");
96 *Ref |= (BranchTargetDisp & ((1 << 21)-1));
102 void AlphaCodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) {
103 MCE.StartMachineBasicBlock(&MBB);
104 for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
106 MachineInstr &MI = *I;
107 unsigned Opcode = MI.getOpcode();
108 switch(MI.getOpcode()) {
110 MCE.emitWordLE(getBinaryCodeForInstr(*I));
114 case Alpha::MEMLABEL:
116 case Alpha::IDEF_F32:
117 case Alpha::IDEF_F64:
123 static unsigned getAlphaRegNumber(unsigned Reg) {
125 case Alpha::R0 : case Alpha::F0 : return 0;
126 case Alpha::R1 : case Alpha::F1 : return 1;
127 case Alpha::R2 : case Alpha::F2 : return 2;
128 case Alpha::R3 : case Alpha::F3 : return 3;
129 case Alpha::R4 : case Alpha::F4 : return 4;
130 case Alpha::R5 : case Alpha::F5 : return 5;
131 case Alpha::R6 : case Alpha::F6 : return 6;
132 case Alpha::R7 : case Alpha::F7 : return 7;
133 case Alpha::R8 : case Alpha::F8 : return 8;
134 case Alpha::R9 : case Alpha::F9 : return 9;
135 case Alpha::R10 : case Alpha::F10 : return 10;
136 case Alpha::R11 : case Alpha::F11 : return 11;
137 case Alpha::R12 : case Alpha::F12 : return 12;
138 case Alpha::R13 : case Alpha::F13 : return 13;
139 case Alpha::R14 : case Alpha::F14 : return 14;
140 case Alpha::R15 : case Alpha::F15 : return 15;
141 case Alpha::R16 : case Alpha::F16 : return 16;
142 case Alpha::R17 : case Alpha::F17 : return 17;
143 case Alpha::R18 : case Alpha::F18 : return 18;
144 case Alpha::R19 : case Alpha::F19 : return 19;
145 case Alpha::R20 : case Alpha::F20 : return 20;
146 case Alpha::R21 : case Alpha::F21 : return 21;
147 case Alpha::R22 : case Alpha::F22 : return 22;
148 case Alpha::R23 : case Alpha::F23 : return 23;
149 case Alpha::R24 : case Alpha::F24 : return 24;
150 case Alpha::R25 : case Alpha::F25 : return 25;
151 case Alpha::R26 : case Alpha::F26 : return 26;
152 case Alpha::R27 : case Alpha::F27 : return 27;
153 case Alpha::R28 : case Alpha::F28 : return 28;
154 case Alpha::R29 : case Alpha::F29 : return 29;
155 case Alpha::R30 : case Alpha::F30 : return 30;
156 case Alpha::R31 : case Alpha::F31 : return 31;
158 assert(0 && "Unhandled reg");
163 int AlphaCodeEmitter::getMachineOpValue(MachineInstr &MI, MachineOperand &MO) {
165 int rv = 0; // Return value; defaults to 0 for unhandled cases
166 // or things that get fixed up later by the JIT.
168 if (MO.isRegister()) {
169 rv = getAlphaRegNumber(MO.getReg());
170 } else if (MO.isImmediate()) {
171 rv = MO.getImmedValue();
172 } else if (MO.isGlobalAddress() || MO.isExternalSymbol()
173 || MO.isConstantPoolIndex()) {
174 DEBUG(std::cerr << MO << " is a relocated op for " << MI << "\n";);
175 bool isExternal = MO.isExternalSymbol() ||
176 (MO.isGlobalAddress() &&
177 ( MO.getGlobal()->hasWeakLinkage() ||
178 MO.getGlobal()->isExternal()) );
182 switch (MI.getOpcode()) {
184 Reloc = Alpha::reloc_bsr;
199 Reloc = Alpha::reloc_gprellow;
202 Reloc = Alpha::reloc_gprelhigh;
205 Reloc = Alpha::reloc_literal;
210 Reloc = Alpha::reloc_gpdist;
211 Offset = MI.getOperand(3).getImmedValue();
214 assert(0 && "unknown relocatable instruction");
217 if (MO.isGlobalAddress())
218 MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(),
219 Reloc, MO.getGlobal(), Offset,
221 else if (MO.isExternalSymbol())
222 MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(),
223 Reloc, MO.getSymbolName(), Offset,
226 MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(),
227 Reloc, MO.getConstantPoolIndex(),
229 } else if (MO.isMachineBasicBlock()) {
230 unsigned* CurrPC = (unsigned*)(intptr_t)MCE.getCurrentPCValue();
231 BBRefs.push_back(std::make_pair(MO.getMachineBasicBlock(), CurrPC));
233 std::cerr << "ERROR: Unknown type of MachineOperand: " << MO << "\n";
241 #include "AlphaGenCodeEmitter.inc"