summaryrefslogtreecommitdiff
path: root/lib/Target/Sparc/SparcRegisterInfo.cpp
blob: f222382a6bc487fba6f64a4d5e90654c476f4738 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
//===-- SparcRegisterInfo.cpp - SPARC Register Information ----------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the SPARC implementation of the TargetRegisterInfo class.
//
//===----------------------------------------------------------------------===//

#include "SparcRegisterInfo.h"
#include "Sparc.h"
#include "SparcMachineFunctionInfo.h"
#include "SparcSubtarget.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetInstrInfo.h"

#define GET_REGINFO_TARGET_DESC
#include "SparcGenRegisterInfo.inc"

using namespace llvm;

static cl::opt<bool>
ReserveAppRegisters("sparc-reserve-app-registers", cl::Hidden, cl::init(false),
                    cl::desc("Reserve application registers (%g2-%g4)"));

SparcRegisterInfo::SparcRegisterInfo(SparcSubtarget &st)
  : SparcGenRegisterInfo(SP::O7), Subtarget(st) {
}

const uint16_t* SparcRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF)
                                                                         const {
  return CSR_SaveList;
}

const uint32_t*
SparcRegisterInfo::getCallPreservedMask(CallingConv::ID CC) const {
  return CSR_RegMask;
}

const uint32_t*
SparcRegisterInfo::getRTCallPreservedMask(CallingConv::ID CC) const {
  return RTCSR_RegMask;
}

BitVector SparcRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
  BitVector Reserved(getNumRegs());
  // FIXME: G1 reserved for now for large imm generation by frame code.
  Reserved.set(SP::G1);

  // G1-G4 can be used in applications.
  if (ReserveAppRegisters) {
    Reserved.set(SP::G2);
    Reserved.set(SP::G3);
    Reserved.set(SP::G4);
  }
  // G5 is not reserved in 64 bit mode.
  if (!Subtarget.is64Bit())
    Reserved.set(SP::G5);

  Reserved.set(SP::O6);
  Reserved.set(SP::I6);
  Reserved.set(SP::I7);
  Reserved.set(SP::G0);
  Reserved.set(SP::G6);
  Reserved.set(SP::G7);

  // Unaliased double registers are not available in non-V9 targets.
  if (!Subtarget.isV9()) {
    for (unsigned n = 0; n != 16; ++n) {
      for (MCRegAliasIterator AI(SP::D16 + n, this, true); AI.isValid(); ++AI)
        Reserved.set(*AI);
    }
  }

  return Reserved;
}

const TargetRegisterClass*
SparcRegisterInfo::getPointerRegClass(const MachineFunction &MF,
                                      unsigned Kind) const {
  return Subtarget.is64Bit() ? &SP::I64RegsRegClass : &SP::IntRegsRegClass;
}

static void replaceFI(MachineFunction &MF,
                      MachineBasicBlock::iterator II,
                      MachineInstr &MI,
                      DebugLoc dl,
                      unsigned FIOperandNum, int Offset,
                      unsigned FramePtr)
{
  // Replace frame index with a frame pointer reference.
  if (Offset >= -4096 && Offset <= 4095) {
    // If the offset is small enough to fit in the immediate field, directly
    // encode it.
    MI.getOperand(FIOperandNum).ChangeToRegister(FramePtr, false);
    MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
    return;
  }

  const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();

  // FIXME: it would be better to scavenge a register here instead of
  // reserving G1 all of the time.
  if (Offset >= 0) {
    // Emit nonnegaive immediates with sethi + or.
    // sethi %hi(Offset), %g1
    // add %g1, %fp, %g1
    // Insert G1+%lo(offset) into the user.
    BuildMI(*MI.getParent(), II, dl, TII.get(SP::SETHIi), SP::G1)
      .addImm(HI22(Offset));


    // Emit G1 = G1 + I6
    BuildMI(*MI.getParent(), II, dl, TII.get(SP::ADDrr), SP::G1).addReg(SP::G1)
      .addReg(FramePtr);
    // Insert: G1+%lo(offset) into the user.
    MI.getOperand(FIOperandNum).ChangeToRegister(SP::G1, false);
    MI.getOperand(FIOperandNum + 1).ChangeToImmediate(LO10(Offset));
    return;
  }

  // Emit Negative numbers with sethi + xor
  // sethi %hix(Offset), %g1
  // xor  %g1, %lox(offset), %g1
  // add %g1, %fp, %g1
  // Insert: G1 + 0 into the user.
  BuildMI(*MI.getParent(), II, dl, TII.get(SP::SETHIi), SP::G1)
    .addImm(HIX22(Offset));
  BuildMI(*MI.getParent(), II, dl, TII.get(SP::XORri), SP::G1)
    .addReg(SP::G1).addImm(LOX10(Offset));

  BuildMI(*MI.getParent(), II, dl, TII.get(SP::ADDrr), SP::G1).addReg(SP::G1)
    .addReg(FramePtr);
  // Insert: G1+%lo(offset) into the user.
  MI.getOperand(FIOperandNum).ChangeToRegister(SP::G1, false);
  MI.getOperand(FIOperandNum + 1).ChangeToImmediate(0);
}


void
SparcRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
                                       int SPAdj, unsigned FIOperandNum,
                                       RegScavenger *RS) const {
  assert(SPAdj == 0 && "Unexpected");

  MachineInstr &MI = *II;
  DebugLoc dl = MI.getDebugLoc();
  int FrameIndex = MI.getOperand(FIOperandNum).getIndex();

  // Addressable stack objects are accessed using neg. offsets from %fp
  MachineFunction &MF = *MI.getParent()->getParent();
  int64_t Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
                   MI.getOperand(FIOperandNum + 1).getImm() +
                   Subtarget.getStackPointerBias();
  SparcMachineFunctionInfo *FuncInfo = MF.getInfo<SparcMachineFunctionInfo>();
  unsigned FramePtr = SP::I6;
  if (FuncInfo->isLeafProc()) {
    // Use %sp and adjust offset if needed.
    FramePtr = SP::O6;
    int stackSize = MF.getFrameInfo()->getStackSize();
    Offset += (stackSize) ? Subtarget.getAdjustedFrameSize(stackSize) : 0 ;
  }

  if (!Subtarget.isV9() || !Subtarget.hasHardQuad()) {
    if (MI.getOpcode() == SP::STQFri) {
      const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();
      unsigned SrcReg = MI.getOperand(2).getReg();
      unsigned SrcEvenReg = getSubReg(SrcReg, SP::sub_even64);
      unsigned SrcOddReg  = getSubReg(SrcReg, SP::sub_odd64);
      MachineInstr *StMI =
        BuildMI(*MI.getParent(), II, dl, TII.get(SP::STDFri))
        .addReg(FramePtr).addImm(0).addReg(SrcEvenReg);
      replaceFI(MF, II, *StMI, dl, 0, Offset, FramePtr);
      MI.setDesc(TII.get(SP::STDFri));
      MI.getOperand(2).setReg(SrcOddReg);
      Offset += 8;
    } else if (MI.getOpcode() == SP::LDQFri) {
      const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();
      unsigned DestReg     = MI.getOperand(0).getReg();
      unsigned DestEvenReg = getSubReg(DestReg, SP::sub_even64);
      unsigned DestOddReg  = getSubReg(DestReg, SP::sub_odd64);
      MachineInstr *StMI =
        BuildMI(*MI.getParent(), II, dl, TII.get(SP::LDDFri), DestEvenReg)
        .addReg(FramePtr).addImm(0);
      replaceFI(MF, II, *StMI, dl, 1, Offset, FramePtr);

      MI.setDesc(TII.get(SP::LDDFri));
      MI.getOperand(0).setReg(DestOddReg);
      Offset += 8;
    }
  }

  replaceFI(MF, II, MI, dl, FIOperandNum, Offset, FramePtr);

}

unsigned SparcRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
  return SP::I6;
}