1//===-- VERegisterInfo.cpp - VE Register Information ----------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file contains the VE implementation of the TargetRegisterInfo class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "VERegisterInfo.h"
14#include "VE.h"
15#include "VESubtarget.h"
16#include "llvm/ADT/BitVector.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/CodeGen/MachineFrameInfo.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/MachineInstrBuilder.h"
21#include "llvm/CodeGen/MachineRegisterInfo.h"
22#include "llvm/CodeGen/TargetInstrInfo.h"
23#include "llvm/IR/Type.h"
24#include "llvm/Support/CommandLine.h"
25#include "llvm/Support/Debug.h"
26#include "llvm/Support/ErrorHandling.h"
27
28using namespace llvm;
29
30#define DEBUG_TYPE "ve-register-info"
31
32#define GET_REGINFO_TARGET_DESC
33#include "VEGenRegisterInfo.inc"
34
35// VE uses %s10 == %lp to keep return address
36VERegisterInfo::VERegisterInfo() : VEGenRegisterInfo(VE::SX10) {}
37
38const MCPhysReg *
39VERegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
40 switch (MF->getFunction().getCallingConv()) {
41 case CallingConv::Fast:
42 // Being explicit (same as standard CC).
43 default:
44 return CSR_SaveList;
45 case CallingConv::PreserveAll:
46 return CSR_preserve_all_SaveList;
47 }
48}
49
50const uint32_t *VERegisterInfo::getCallPreservedMask(const MachineFunction &MF,
51 CallingConv::ID CC) const {
52 switch (CC) {
53 case CallingConv::Fast:
54 // Being explicit (same as standard CC).
55 default:
56 return CSR_RegMask;
57 case CallingConv::PreserveAll:
58 return CSR_preserve_all_RegMask;
59 }
60}
61
62const uint32_t *VERegisterInfo::getNoPreservedMask() const {
63 return CSR_NoRegs_RegMask;
64}
65
66BitVector VERegisterInfo::getReservedRegs(const MachineFunction &MF) const {
67 BitVector Reserved(getNumRegs());
68
69 const Register ReservedRegs[] = {
70 VE::SX8, // Stack limit
71 VE::SX9, // Frame pointer
72 VE::SX10, // Link register (return address)
73 VE::SX11, // Stack pointer
74
75 // FIXME: maybe not need to be reserved
76 VE::SX12, // Outer register
77 VE::SX13, // Id register for dynamic linker
78
79 VE::SX14, // Thread pointer
80 VE::SX15, // Global offset table register
81 VE::SX16, // Procedure linkage table register
82 VE::SX17, // Linkage-area register
83 // sx18-sx33 are callee-saved registers
84 // sx34-sx63 are temporary registers
85 };
86
87 for (auto R : ReservedRegs)
88 for (MCRegAliasIterator ItAlias(R, this, true); ItAlias.isValid();
89 ++ItAlias)
90 Reserved.set(*ItAlias);
91
92 // Reserve constant registers.
93 Reserved.set(VE::VM0);
94 Reserved.set(VE::VMP0);
95
96 return Reserved;
97}
98
99const TargetRegisterClass *
100VERegisterInfo::getPointerRegClass(const MachineFunction &MF,
101 unsigned Kind) const {
102 return &VE::I64RegClass;
103}
104
105static unsigned offsetToDisp(MachineInstr &MI) {
106 // Default offset in instruction's operands (reg+reg+imm).
107 unsigned OffDisp = 2;
108
109#define RRCAS_multi_cases(NAME) NAME##rir : case NAME##rii
110
111 {
112 using namespace llvm::VE;
113 switch (MI.getOpcode()) {
114 case INLINEASM:
115 case RRCAS_multi_cases(TS1AML):
116 case RRCAS_multi_cases(TS1AMW):
117 case RRCAS_multi_cases(CASL):
118 case RRCAS_multi_cases(CASW):
119 // These instructions use AS format (reg+imm).
120 OffDisp = 1;
121 break;
122 }
123 }
124#undef RRCAS_multi_cases
125
126 return OffDisp;
127}
128
129namespace {
130class EliminateFrameIndex {
131 const TargetInstrInfo &TII;
132 const TargetRegisterInfo &TRI;
133 const DebugLoc &DL;
134 MachineBasicBlock &MBB;
135 MachineBasicBlock::iterator II;
136 Register clobber;
137
138 // Some helper functions for the ease of instruction building.
139 MachineFunction &getFunc() const { return *MBB.getParent(); }
140 inline MCRegister getSubReg(MCRegister Reg, unsigned Idx) const {
141 return TRI.getSubReg(Reg, Idx);
142 }
143 inline const MCInstrDesc &get(unsigned Opcode) const {
144 return TII.get(Opcode);
145 }
146 inline MachineInstrBuilder build(const MCInstrDesc &MCID, Register DestReg) {
147 return BuildMI(BB&: MBB, I: II, MIMD: DL, MCID, DestReg);
148 }
149 inline MachineInstrBuilder build(unsigned InstOpc, Register DestReg) {
150 return build(MCID: get(Opcode: InstOpc), DestReg);
151 }
152 inline MachineInstrBuilder build(const MCInstrDesc &MCID) {
153 return BuildMI(BB&: MBB, I: II, MIMD: DL, MCID);
154 }
155 inline MachineInstrBuilder build(unsigned InstOpc) {
156 return build(MCID: get(Opcode: InstOpc));
157 }
158
159 // Calculate an address of frame index from a frame register and a given
160 // offset if the offset doesn't fit in the immediate field. Use a clobber
161 // register to hold calculated address.
162 void prepareReplaceFI(MachineInstr &MI, Register &FrameReg, int64_t &Offset,
163 int64_t Bytes = 0);
164 // Replace the frame index in \p MI with a frame register and a given offset
165 // if it fits in the immediate field. Otherwise, use pre-calculated address
166 // in a clobber regsiter.
167 void replaceFI(MachineInstr &MI, Register FrameReg, int64_t Offset,
168 int FIOperandNum);
169
170 // Expand and eliminate Frame Index of pseudo STQrii and LDQrii.
171 void processSTQ(MachineInstr &MI, Register FrameReg, int64_t Offset,
172 int FIOperandNum);
173 void processLDQ(MachineInstr &MI, Register FrameReg, int64_t Offset,
174 int FIOperandNum);
175 // Expand and eliminate Frame Index of pseudo STVMrii and LDVMrii.
176 void processSTVM(MachineInstr &MI, Register FrameReg, int64_t Offset,
177 int FIOperandNum);
178 void processLDVM(MachineInstr &MI, Register FrameReg, int64_t Offset,
179 int FIOperandNum);
180 // Expand and eliminate Frame Index of pseudo STVM512rii and LDVM512rii.
181 void processSTVM512(MachineInstr &MI, Register FrameReg, int64_t Offset,
182 int FIOperandNum);
183 void processLDVM512(MachineInstr &MI, Register FrameReg, int64_t Offset,
184 int FIOperandNum);
185
186public:
187 EliminateFrameIndex(const TargetInstrInfo &TII, const TargetRegisterInfo &TRI,
188 const DebugLoc &DL, MachineBasicBlock &MBB,
189 MachineBasicBlock::iterator II)
190 : TII(TII), TRI(TRI), DL(DL), MBB(MBB), II(II), clobber(VE::SX13) {}
191
192 // Expand and eliminate Frame Index from MI
193 void processMI(MachineInstr &MI, Register FrameReg, int64_t Offset,
194 int FIOperandNum);
195};
196} // namespace
197
198// Prepare the frame index if it doesn't fit in the immediate field. Use
199// clobber register to hold calculated address.
200void EliminateFrameIndex::prepareReplaceFI(MachineInstr &MI, Register &FrameReg,
201 int64_t &Offset, int64_t Bytes) {
202 if (isInt<32>(x: Offset) && isInt<32>(x: Offset + Bytes)) {
203 // If the offset is small enough to fit in the immediate field, directly
204 // encode it. So, nothing to prepare here.
205 return;
206 }
207
208 // If the offset doesn't fit, emit following codes. This clobbers SX13
209 // which we always know is available here.
210 // lea %clobber, Offset@lo
211 // and %clobber, %clobber, (32)0
212 // lea.sl %clobber, Offset@hi(FrameReg, %clobber)
213 build(VE::LEAzii, clobber).addImm(0).addImm(0).addImm(Lo_32(Offset));
214 build(VE::ANDrm, clobber).addReg(clobber).addImm(M0(32));
215 build(VE::LEASLrri, clobber)
216 .addReg(clobber)
217 .addReg(FrameReg)
218 .addImm(Hi_32(Offset));
219
220 // Use clobber register as a frame register and 0 offset
221 FrameReg = clobber;
222 Offset = 0;
223}
224
225// Replace the frame index in \p MI with a proper byte and framereg offset.
226void EliminateFrameIndex::replaceFI(MachineInstr &MI, Register FrameReg,
227 int64_t Offset, int FIOperandNum) {
228 assert(isInt<32>(Offset));
229
230 // The offset must be small enough to fit in the immediate field after
231 // call of prepareReplaceFI. Therefore, we directly encode it.
232 MI.getOperand(i: FIOperandNum).ChangeToRegister(Reg: FrameReg, isDef: false);
233 MI.getOperand(i: FIOperandNum + offsetToDisp(MI)).ChangeToImmediate(ImmVal: Offset);
234}
235
236void EliminateFrameIndex::processSTQ(MachineInstr &MI, Register FrameReg,
237 int64_t Offset, int FIOperandNum) {
238 assert(MI.getOpcode() == VE::STQrii);
239 LLVM_DEBUG(dbgs() << "processSTQ: "; MI.dump());
240
241 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 8);
242
243 Register SrcReg = MI.getOperand(i: 3).getReg();
244 Register SrcHiReg = getSubReg(SrcReg, VE::sub_even);
245 Register SrcLoReg = getSubReg(SrcReg, VE::sub_odd);
246 // VE stores HiReg to 8(addr) and LoReg to 0(addr)
247 MachineInstr *StMI =
248 build(VE::STrii).addReg(FrameReg).addImm(0).addImm(0).addReg(SrcLoReg);
249 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 0);
250 // Mutate to 'hi' store.
251 MI.setDesc(get(VE::STrii));
252 MI.getOperand(i: 3).setReg(SrcHiReg);
253 Offset += 8;
254 replaceFI(MI, FrameReg, Offset, FIOperandNum);
255}
256
257void EliminateFrameIndex::processLDQ(MachineInstr &MI, Register FrameReg,
258 int64_t Offset, int FIOperandNum) {
259 assert(MI.getOpcode() == VE::LDQrii);
260 LLVM_DEBUG(dbgs() << "processLDQ: "; MI.dump());
261
262 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 8);
263
264 Register DestReg = MI.getOperand(i: 0).getReg();
265 Register DestHiReg = getSubReg(DestReg, VE::sub_even);
266 Register DestLoReg = getSubReg(DestReg, VE::sub_odd);
267 // VE loads HiReg from 8(addr) and LoReg from 0(addr)
268 MachineInstr *StMI =
269 build(VE::LDrii, DestLoReg).addReg(FrameReg).addImm(0).addImm(0);
270 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 1);
271 MI.setDesc(get(VE::LDrii));
272 MI.getOperand(i: 0).setReg(DestHiReg);
273 Offset += 8;
274 replaceFI(MI, FrameReg, Offset, FIOperandNum);
275}
276
277void EliminateFrameIndex::processSTVM(MachineInstr &MI, Register FrameReg,
278 int64_t Offset, int FIOperandNum) {
279 assert(MI.getOpcode() == VE::STVMrii);
280 LLVM_DEBUG(dbgs() << "processSTVM: "; MI.dump());
281
282 // Original MI is:
283 // STVMrii frame-index, 0, offset, reg (, memory operand)
284 // Convert it to:
285 // SVMi tmp-reg, reg, 0
286 // STrii frame-reg, 0, offset, tmp-reg
287 // SVMi tmp-reg, reg, 1
288 // STrii frame-reg, 0, offset+8, tmp-reg
289 // SVMi tmp-reg, reg, 2
290 // STrii frame-reg, 0, offset+16, tmp-reg
291 // SVMi tmp-reg, reg, 3
292 // STrii frame-reg, 0, offset+24, tmp-reg
293
294 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 24);
295
296 Register SrcReg = MI.getOperand(i: 3).getReg();
297 bool isKill = MI.getOperand(i: 3).isKill();
298 // FIXME: it would be better to scavenge a register here instead of
299 // reserving SX16 all of the time.
300 Register TmpReg = VE::SX16;
301 for (int i = 0; i < 3; ++i) {
302 build(VE::SVMmr, TmpReg).addReg(SrcReg).addImm(i);
303 MachineInstr *StMI =
304 build(VE::STrii).addReg(FrameReg).addImm(0).addImm(0).addReg(
305 TmpReg, getKillRegState(true));
306 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 0);
307 Offset += 8;
308 }
309 build(VE::SVMmr, TmpReg).addReg(SrcReg, getKillRegState(isKill)).addImm(3);
310 MI.setDesc(get(VE::STrii));
311 MI.getOperand(i: 3).ChangeToRegister(Reg: TmpReg, isDef: false, isImp: false, isKill: true);
312 replaceFI(MI, FrameReg, Offset, FIOperandNum);
313}
314
315void EliminateFrameIndex::processLDVM(MachineInstr &MI, Register FrameReg,
316 int64_t Offset, int FIOperandNum) {
317 assert(MI.getOpcode() == VE::LDVMrii);
318 LLVM_DEBUG(dbgs() << "processLDVM: "; MI.dump());
319
320 // Original MI is:
321 // LDVMri reg, frame-index, 0, offset (, memory operand)
322 // Convert it to:
323 // LDrii tmp-reg, frame-reg, 0, offset
324 // LVMir vm, 0, tmp-reg
325 // LDrii tmp-reg, frame-reg, 0, offset+8
326 // LVMir_m vm, 1, tmp-reg, vm
327 // LDrii tmp-reg, frame-reg, 0, offset+16
328 // LVMir_m vm, 2, tmp-reg, vm
329 // LDrii tmp-reg, frame-reg, 0, offset+24
330 // LVMir_m vm, 3, tmp-reg, vm
331
332 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 24);
333
334 Register DestReg = MI.getOperand(i: 0).getReg();
335 // FIXME: it would be better to scavenge a register here instead of
336 // reserving SX16 all of the time.
337 unsigned TmpReg = VE::SX16;
338 for (int i = 0; i < 4; ++i) {
339 if (i != 3) {
340 MachineInstr *StMI =
341 build(VE::LDrii, TmpReg).addReg(FrameReg).addImm(0).addImm(0);
342 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 1);
343 Offset += 8;
344 } else {
345 // Last LDrii replace the target instruction.
346 MI.setDesc(get(VE::LDrii));
347 MI.getOperand(i: 0).ChangeToRegister(Reg: TmpReg, isDef: true);
348 }
349 // First LVM is LVMir. Others are LVMir_m. Last LVM places at the
350 // next of the target instruction.
351 if (i == 0)
352 build(VE::LVMir, DestReg).addImm(i).addReg(TmpReg, getKillRegState(true));
353 else if (i != 3)
354 build(VE::LVMir_m, DestReg)
355 .addImm(i)
356 .addReg(TmpReg, getKillRegState(true))
357 .addReg(DestReg);
358 else
359 BuildMI(*MI.getParent(), std::next(II), DL, get(VE::LVMir_m), DestReg)
360 .addImm(3)
361 .addReg(TmpReg, getKillRegState(true))
362 .addReg(DestReg);
363 }
364 replaceFI(MI, FrameReg, Offset, FIOperandNum);
365}
366
367void EliminateFrameIndex::processSTVM512(MachineInstr &MI, Register FrameReg,
368 int64_t Offset, int FIOperandNum) {
369 assert(MI.getOpcode() == VE::STVM512rii);
370 LLVM_DEBUG(dbgs() << "processSTVM512: "; MI.dump());
371
372 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 56);
373
374 Register SrcReg = MI.getOperand(i: 3).getReg();
375 Register SrcLoReg = getSubReg(SrcReg, VE::sub_vm_odd);
376 Register SrcHiReg = getSubReg(SrcReg, VE::sub_vm_even);
377 bool isKill = MI.getOperand(i: 3).isKill();
378 // FIXME: it would be better to scavenge a register here instead of
379 // reserving SX16 all of the time.
380 Register TmpReg = VE::SX16;
381 // store low part of VMP
382 MachineInstr *LastMI = nullptr;
383 for (int i = 0; i < 4; ++i) {
384 LastMI = build(VE::SVMmr, TmpReg).addReg(SrcLoReg).addImm(i);
385 MachineInstr *StMI =
386 build(VE::STrii).addReg(FrameReg).addImm(0).addImm(0).addReg(
387 TmpReg, getKillRegState(true));
388 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 0);
389 Offset += 8;
390 }
391 if (isKill)
392 LastMI->addRegisterKilled(IncomingReg: SrcLoReg, RegInfo: &TRI, AddIfNotFound: true);
393 // store high part of VMP
394 for (int i = 0; i < 3; ++i) {
395 build(VE::SVMmr, TmpReg).addReg(SrcHiReg).addImm(i);
396 MachineInstr *StMI =
397 build(VE::STrii).addReg(FrameReg).addImm(0).addImm(0).addReg(
398 TmpReg, getKillRegState(true));
399 replaceFI(MI&: *StMI, FrameReg, Offset, FIOperandNum: 0);
400 Offset += 8;
401 }
402 LastMI = build(VE::SVMmr, TmpReg).addReg(SrcHiReg).addImm(3);
403 if (isKill) {
404 LastMI->addRegisterKilled(IncomingReg: SrcHiReg, RegInfo: &TRI, AddIfNotFound: true);
405 // Add implicit super-register kills to the particular MI.
406 LastMI->addRegisterKilled(IncomingReg: SrcReg, RegInfo: &TRI, AddIfNotFound: true);
407 }
408 MI.setDesc(get(VE::STrii));
409 MI.getOperand(i: 3).ChangeToRegister(Reg: TmpReg, isDef: false, isImp: false, isKill: true);
410 replaceFI(MI, FrameReg, Offset, FIOperandNum);
411}
412
413void EliminateFrameIndex::processLDVM512(MachineInstr &MI, Register FrameReg,
414 int64_t Offset, int FIOperandNum) {
415 assert(MI.getOpcode() == VE::LDVM512rii);
416 LLVM_DEBUG(dbgs() << "processLDVM512: "; MI.dump());
417
418 prepareReplaceFI(MI, FrameReg, Offset, Bytes: 56);
419
420 Register DestReg = MI.getOperand(i: 0).getReg();
421 Register DestLoReg = getSubReg(DestReg, VE::sub_vm_odd);
422 Register DestHiReg = getSubReg(DestReg, VE::sub_vm_even);
423 // FIXME: it would be better to scavenge a register here instead of
424 // reserving SX16 all of the time.
425 Register TmpReg = VE::SX16;
426 build(VE::IMPLICIT_DEF, DestReg);
427 for (int i = 0; i < 4; ++i) {
428 MachineInstr *LdMI =
429 build(VE::LDrii, TmpReg).addReg(FrameReg).addImm(0).addImm(0);
430 replaceFI(MI&: *LdMI, FrameReg, Offset, FIOperandNum: 1);
431 build(VE::LVMir_m, DestLoReg)
432 .addImm(i)
433 .addReg(TmpReg, getKillRegState(true))
434 .addReg(DestLoReg);
435 Offset += 8;
436 }
437 for (int i = 0; i < 3; ++i) {
438 MachineInstr *LdMI =
439 build(VE::LDrii, TmpReg).addReg(FrameReg).addImm(0).addImm(0);
440 replaceFI(MI&: *LdMI, FrameReg, Offset, FIOperandNum: 1);
441 build(VE::LVMir_m, DestHiReg)
442 .addImm(i)
443 .addReg(TmpReg, getKillRegState(true))
444 .addReg(DestHiReg);
445 Offset += 8;
446 }
447 MI.setDesc(get(VE::LDrii));
448 MI.getOperand(i: 0).ChangeToRegister(Reg: TmpReg, isDef: true);
449 BuildMI(*MI.getParent(), std::next(II), DL, get(VE::LVMir_m), DestHiReg)
450 .addImm(3)
451 .addReg(TmpReg, getKillRegState(true))
452 .addReg(DestHiReg);
453 replaceFI(MI, FrameReg, Offset, FIOperandNum);
454}
455
456void EliminateFrameIndex::processMI(MachineInstr &MI, Register FrameReg,
457 int64_t Offset, int FIOperandNum) {
458 switch (MI.getOpcode()) {
459 case VE::STQrii:
460 processSTQ(MI, FrameReg, Offset, FIOperandNum);
461 return;
462 case VE::LDQrii:
463 processLDQ(MI, FrameReg, Offset, FIOperandNum);
464 return;
465 case VE::STVMrii:
466 processSTVM(MI, FrameReg, Offset, FIOperandNum);
467 return;
468 case VE::LDVMrii:
469 processLDVM(MI, FrameReg, Offset, FIOperandNum);
470 return;
471 case VE::STVM512rii:
472 processSTVM512(MI, FrameReg, Offset, FIOperandNum);
473 return;
474 case VE::LDVM512rii:
475 processLDVM512(MI, FrameReg, Offset, FIOperandNum);
476 return;
477 }
478 prepareReplaceFI(MI, FrameReg, Offset);
479 replaceFI(MI, FrameReg, Offset, FIOperandNum);
480}
481
482bool VERegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
483 int SPAdj, unsigned FIOperandNum,
484 RegScavenger *RS) const {
485 assert(SPAdj == 0 && "Unexpected");
486
487 MachineInstr &MI = *II;
488 int FrameIndex = MI.getOperand(i: FIOperandNum).getIndex();
489
490 MachineFunction &MF = *MI.getParent()->getParent();
491 const VESubtarget &Subtarget = MF.getSubtarget<VESubtarget>();
492 const VEFrameLowering &TFI = *getFrameLowering(MF);
493 const TargetInstrInfo &TII = *Subtarget.getInstrInfo();
494 const VERegisterInfo &TRI = *Subtarget.getRegisterInfo();
495 DebugLoc DL = MI.getDebugLoc();
496 EliminateFrameIndex EFI(TII, TRI, DL, *MI.getParent(), II);
497
498 // Retrieve FrameReg and byte offset for stack slot.
499 Register FrameReg;
500 int64_t Offset =
501 TFI.getFrameIndexReference(MF, FI: FrameIndex, FrameReg).getFixed();
502 Offset += MI.getOperand(i: FIOperandNum + offsetToDisp(MI)).getImm();
503
504 EFI.processMI(MI, FrameReg, Offset, FIOperandNum);
505 return false;
506}
507
508Register VERegisterInfo::getFrameRegister(const MachineFunction &MF) const {
509 return VE::SX9;
510}
511

source code of llvm/lib/Target/VE/VERegisterInfo.cpp