1 //===-- HexagonRegisterInfo.cpp - Hexagon 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 Hexagon implementation of the TargetRegisterInfo
11 // class.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "HexagonRegisterInfo.h"
16 #include "Hexagon.h"
17 #include "HexagonMachineFunctionInfo.h"
18 #include "HexagonSubtarget.h"
19 #include "HexagonTargetMachine.h"
20 #include "llvm/ADT/BitVector.h"
21 #include "llvm/ADT/STLExtras.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineFunctionPass.h"
25 #include "llvm/CodeGen/MachineInstrBuilder.h"
26 #include "llvm/CodeGen/MachineRegisterInfo.h"
27 #include "llvm/CodeGen/PseudoSourceValue.h"
28 #include "llvm/CodeGen/RegisterScavenging.h"
29 #include "llvm/IR/Function.h"
30 #include "llvm/IR/Type.h"
31 #include "llvm/MC/MachineLocation.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Target/TargetInstrInfo.h"
35 #include "llvm/Target/TargetMachine.h"
36 #include "llvm/Target/TargetOptions.h"
37
38 using namespace llvm;
39
40
HexagonRegisterInfo(HexagonSubtarget & st)41 HexagonRegisterInfo::HexagonRegisterInfo(HexagonSubtarget &st)
42 : HexagonGenRegisterInfo(Hexagon::R31),
43 Subtarget(st) {
44 }
45
46 const MCPhysReg *
getCalleeSavedRegs(const MachineFunction * MF) const47 HexagonRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
48 static const MCPhysReg CalleeSavedRegsV2[] = {
49 Hexagon::R24, Hexagon::R25, Hexagon::R26, Hexagon::R27, 0
50 };
51 static const MCPhysReg CalleeSavedRegsV3[] = {
52 Hexagon::R16, Hexagon::R17, Hexagon::R18, Hexagon::R19,
53 Hexagon::R20, Hexagon::R21, Hexagon::R22, Hexagon::R23,
54 Hexagon::R24, Hexagon::R25, Hexagon::R26, Hexagon::R27, 0
55 };
56
57 switch(Subtarget.getHexagonArchVersion()) {
58 case HexagonSubtarget::V1:
59 break;
60 case HexagonSubtarget::V2:
61 return CalleeSavedRegsV2;
62 case HexagonSubtarget::V3:
63 case HexagonSubtarget::V4:
64 case HexagonSubtarget::V5:
65 return CalleeSavedRegsV3;
66 }
67 llvm_unreachable("Callee saved registers requested for unknown architecture "
68 "version");
69 }
70
getReservedRegs(const MachineFunction & MF) const71 BitVector HexagonRegisterInfo::getReservedRegs(const MachineFunction &MF)
72 const {
73 BitVector Reserved(getNumRegs());
74 Reserved.set(HEXAGON_RESERVED_REG_1);
75 Reserved.set(HEXAGON_RESERVED_REG_2);
76 Reserved.set(Hexagon::R29);
77 Reserved.set(Hexagon::R30);
78 Reserved.set(Hexagon::R31);
79 Reserved.set(Hexagon::D14);
80 Reserved.set(Hexagon::D15);
81 Reserved.set(Hexagon::LC0);
82 Reserved.set(Hexagon::LC1);
83 Reserved.set(Hexagon::SA0);
84 Reserved.set(Hexagon::SA1);
85 return Reserved;
86 }
87
88
89 const TargetRegisterClass* const*
getCalleeSavedRegClasses(const MachineFunction * MF) const90 HexagonRegisterInfo::getCalleeSavedRegClasses(const MachineFunction *MF) const {
91 static const TargetRegisterClass * const CalleeSavedRegClassesV2[] = {
92 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
93 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
94 };
95 static const TargetRegisterClass * const CalleeSavedRegClassesV3[] = {
96 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
97 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
98 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
99 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
100 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
101 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
102 };
103
104 switch(Subtarget.getHexagonArchVersion()) {
105 case HexagonSubtarget::V1:
106 break;
107 case HexagonSubtarget::V2:
108 return CalleeSavedRegClassesV2;
109 case HexagonSubtarget::V3:
110 case HexagonSubtarget::V4:
111 case HexagonSubtarget::V5:
112 return CalleeSavedRegClassesV3;
113 }
114 llvm_unreachable("Callee saved register classes requested for unknown "
115 "architecture version");
116 }
117
eliminateFrameIndex(MachineBasicBlock::iterator II,int SPAdj,unsigned FIOperandNum,RegScavenger * RS) const118 void HexagonRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
119 int SPAdj, unsigned FIOperandNum,
120 RegScavenger *RS) const {
121 //
122 // Hexagon_TODO: Do we need to enforce this for Hexagon?
123 assert(SPAdj == 0 && "Unexpected");
124
125 MachineInstr &MI = *II;
126 int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
127
128 // Addressable stack objects are accessed using neg. offsets from %fp.
129 MachineFunction &MF = *MI.getParent()->getParent();
130 const HexagonInstrInfo &TII =
131 *static_cast<const HexagonInstrInfo *>(MF.getSubtarget().getInstrInfo());
132 int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
133 MachineFrameInfo &MFI = *MF.getFrameInfo();
134
135 unsigned FrameReg = getFrameRegister(MF);
136 const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
137 if (!TFI->hasFP(MF)) {
138 // We will not reserve space on the stack for the lr and fp registers.
139 Offset -= 2 * Hexagon_WordSize;
140 }
141
142 const unsigned FrameSize = MFI.getStackSize();
143
144 if (!MFI.hasVarSizedObjects() &&
145 TII.isValidOffset(MI.getOpcode(), (FrameSize+Offset)) &&
146 !TII.isSpillPredRegOp(&MI)) {
147 // Replace frame index with a stack pointer reference.
148 MI.getOperand(FIOperandNum).ChangeToRegister(getStackRegister(), false,
149 false, true);
150 MI.getOperand(FIOperandNum + 1).ChangeToImmediate(FrameSize+Offset);
151 } else {
152 // Replace frame index with a frame pointer reference.
153 if (!TII.isValidOffset(MI.getOpcode(), Offset)) {
154
155 // If the offset overflows, then correct it.
156 //
157 // For loads, we do not need a reserved register
158 // r0 = memw(r30 + #10000) to:
159 //
160 // r0 = add(r30, #10000)
161 // r0 = memw(r0)
162 if ( (MI.getOpcode() == Hexagon::L2_loadri_io) ||
163 (MI.getOpcode() == Hexagon::L2_loadrd_io) ||
164 (MI.getOpcode() == Hexagon::L2_loadrh_io) ||
165 (MI.getOpcode() == Hexagon::L2_loadruh_io) ||
166 (MI.getOpcode() == Hexagon::L2_loadrb_io) ||
167 (MI.getOpcode() == Hexagon::L2_loadrub_io) ||
168 (MI.getOpcode() == Hexagon::LDriw_f) ||
169 (MI.getOpcode() == Hexagon::LDrid_f)) {
170 unsigned dstReg = (MI.getOpcode() == Hexagon::L2_loadrd_io) ?
171 getSubReg(MI.getOperand(0).getReg(), Hexagon::subreg_loreg) :
172 MI.getOperand(0).getReg();
173
174 // Check if offset can fit in addi.
175 if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
176 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
177 TII.get(Hexagon::CONST32_Int_Real), dstReg).addImm(Offset);
178 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
179 TII.get(Hexagon::A2_add),
180 dstReg).addReg(FrameReg).addReg(dstReg);
181 } else {
182 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
183 TII.get(Hexagon::ADD_ri),
184 dstReg).addReg(FrameReg).addImm(Offset);
185 }
186
187 MI.getOperand(FIOperandNum).ChangeToRegister(dstReg, false, false,true);
188 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
189 } else if ((MI.getOpcode() == Hexagon::S2_storeri_io) ||
190 (MI.getOpcode() == Hexagon::S2_storerd_io) ||
191 (MI.getOpcode() == Hexagon::S2_storerh_io) ||
192 (MI.getOpcode() == Hexagon::S2_storerb_io) ||
193 (MI.getOpcode() == Hexagon::STrid_f) ||
194 (MI.getOpcode() == Hexagon::STriw_f)) {
195 // For stores, we need a reserved register. Change
196 // memw(r30 + #10000) = r0 to:
197 //
198 // rs = add(r30, #10000);
199 // memw(rs) = r0
200 unsigned resReg = HEXAGON_RESERVED_REG_1;
201
202 // Check if offset can fit in addi.
203 if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
204 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
205 TII.get(Hexagon::CONST32_Int_Real), resReg).addImm(Offset);
206 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
207 TII.get(Hexagon::A2_add),
208 resReg).addReg(FrameReg).addReg(resReg);
209 } else {
210 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
211 TII.get(Hexagon::ADD_ri),
212 resReg).addReg(FrameReg).addImm(Offset);
213 }
214 MI.getOperand(FIOperandNum).ChangeToRegister(resReg, false, false,true);
215 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
216 } else if (TII.isMemOp(&MI)) {
217 // use the constant extender if the instruction provides it
218 // and we are V4TOps.
219 if (Subtarget.hasV4TOps()) {
220 if (TII.isConstExtended(&MI)) {
221 MI.getOperand(FIOperandNum).ChangeToRegister(FrameReg, false);
222 MI.getOperand(FIOperandNum+1).ChangeToImmediate(Offset);
223 TII.immediateExtend(&MI);
224 } else {
225 llvm_unreachable("Need to implement for memops");
226 }
227 } else {
228 // Only V3 and older instructions here.
229 unsigned ResReg = HEXAGON_RESERVED_REG_1;
230 if (!MFI.hasVarSizedObjects() &&
231 TII.isValidOffset(MI.getOpcode(), (FrameSize+Offset))) {
232 MI.getOperand(FIOperandNum).ChangeToRegister(getStackRegister(),
233 false, false, false);
234 MI.getOperand(FIOperandNum+1).ChangeToImmediate(FrameSize+Offset);
235 } else if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
236 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
237 TII.get(Hexagon::CONST32_Int_Real), ResReg).addImm(Offset);
238 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
239 TII.get(Hexagon::A2_add), ResReg).addReg(FrameReg).
240 addReg(ResReg);
241 MI.getOperand(FIOperandNum).ChangeToRegister(ResReg, false, false,
242 true);
243 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
244 } else {
245 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
246 TII.get(Hexagon::ADD_ri), ResReg).addReg(FrameReg).
247 addImm(Offset);
248 MI.getOperand(FIOperandNum).ChangeToRegister(ResReg, false, false,
249 true);
250 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
251 }
252 }
253 } else {
254 unsigned dstReg = MI.getOperand(0).getReg();
255 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
256 TII.get(Hexagon::CONST32_Int_Real), dstReg).addImm(Offset);
257 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
258 TII.get(Hexagon::A2_add),
259 dstReg).addReg(FrameReg).addReg(dstReg);
260 // Can we delete MI??? r2 = add (r2, #0).
261 MI.getOperand(FIOperandNum).ChangeToRegister(dstReg, false, false,true);
262 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
263 }
264 } else {
265 // If the offset is small enough to fit in the immediate field, directly
266 // encode it.
267 MI.getOperand(FIOperandNum).ChangeToRegister(FrameReg, false);
268 MI.getOperand(FIOperandNum+1).ChangeToImmediate(Offset);
269 }
270 }
271
272 }
273
getRARegister() const274 unsigned HexagonRegisterInfo::getRARegister() const {
275 return Hexagon::R31;
276 }
277
getFrameRegister(const MachineFunction & MF) const278 unsigned HexagonRegisterInfo::getFrameRegister(const MachineFunction
279 &MF) const {
280 const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
281 if (TFI->hasFP(MF)) {
282 return Hexagon::R30;
283 }
284
285 return Hexagon::R29;
286 }
287
getFrameRegister() const288 unsigned HexagonRegisterInfo::getFrameRegister() const {
289 return Hexagon::R30;
290 }
291
getStackRegister() const292 unsigned HexagonRegisterInfo::getStackRegister() const {
293 return Hexagon::R29;
294 }
295
296 #define GET_REGINFO_TARGET_DESC
297 #include "HexagonGenRegisterInfo.inc"
298