1 //===-- SparcRegisterInfo.cpp - SPARC Register Information ----------------===//
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 // This file contains the SPARC implementation of the TargetRegisterInfo class.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "SparcRegisterInfo.h"
15 #include "Sparc.h"
16 #include "SparcSubtarget.h"
17 #include "llvm/ADT/BitVector.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/CodeGen/MachineFrameInfo.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineInstrBuilder.h"
22 #include "llvm/IR/Type.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Target/TargetInstrInfo.h"
25
26 #define GET_REGINFO_TARGET_DESC
27 #include "SparcGenRegisterInfo.inc"
28
29 using namespace llvm;
30
SparcRegisterInfo(SparcSubtarget & st,const TargetInstrInfo & tii)31 SparcRegisterInfo::SparcRegisterInfo(SparcSubtarget &st,
32 const TargetInstrInfo &tii)
33 : SparcGenRegisterInfo(SP::I7), Subtarget(st), TII(tii) {
34 }
35
getCalleeSavedRegs(const MachineFunction * MF) const36 const uint16_t* SparcRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF)
37 const {
38 static const uint16_t CalleeSavedRegs[] = { 0 };
39 return CalleeSavedRegs;
40 }
41
getReservedRegs(const MachineFunction & MF) const42 BitVector SparcRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
43 BitVector Reserved(getNumRegs());
44 // FIXME: G1 reserved for now for large imm generation by frame code.
45 Reserved.set(SP::G1);
46 Reserved.set(SP::G2);
47 Reserved.set(SP::G3);
48 Reserved.set(SP::G4);
49 Reserved.set(SP::O6);
50 Reserved.set(SP::I6);
51 Reserved.set(SP::I7);
52 Reserved.set(SP::G0);
53 Reserved.set(SP::G5);
54 Reserved.set(SP::G6);
55 Reserved.set(SP::G7);
56 return Reserved;
57 }
58
59 void
eliminateFrameIndex(MachineBasicBlock::iterator II,int SPAdj,unsigned FIOperandNum,RegScavenger * RS) const60 SparcRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
61 int SPAdj, unsigned FIOperandNum,
62 RegScavenger *RS) const {
63 assert(SPAdj == 0 && "Unexpected");
64
65 MachineInstr &MI = *II;
66 DebugLoc dl = MI.getDebugLoc();
67 int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
68
69 // Addressable stack objects are accessed using neg. offsets from %fp
70 MachineFunction &MF = *MI.getParent()->getParent();
71 int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
72 MI.getOperand(FIOperandNum + 1).getImm();
73
74 // Replace frame index with a frame pointer reference.
75 if (Offset >= -4096 && Offset <= 4095) {
76 // If the offset is small enough to fit in the immediate field, directly
77 // encode it.
78 MI.getOperand(FIOperandNum).ChangeToRegister(SP::I6, false);
79 MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
80 } else {
81 // Otherwise, emit a G1 = SETHI %hi(offset). FIXME: it would be better to
82 // scavenge a register here instead of reserving G1 all of the time.
83 unsigned OffHi = (unsigned)Offset >> 10U;
84 BuildMI(*MI.getParent(), II, dl, TII.get(SP::SETHIi), SP::G1).addImm(OffHi);
85 // Emit G1 = G1 + I6
86 BuildMI(*MI.getParent(), II, dl, TII.get(SP::ADDrr), SP::G1).addReg(SP::G1)
87 .addReg(SP::I6);
88 // Insert: G1+%lo(offset) into the user.
89 MI.getOperand(FIOperandNum).ChangeToRegister(SP::G1, false);
90 MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset & ((1 << 10)-1));
91 }
92 }
93
getFrameRegister(const MachineFunction & MF) const94 unsigned SparcRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
95 return SP::I6;
96 }
97
getEHExceptionRegister() const98 unsigned SparcRegisterInfo::getEHExceptionRegister() const {
99 llvm_unreachable("What is the exception register");
100 }
101
getEHHandlerRegister() const102 unsigned SparcRegisterInfo::getEHHandlerRegister() const {
103 llvm_unreachable("What is the exception handler register");
104 }
105