1 //===- TargetLoweringBase.cpp - Implement the TargetLoweringBase class ----===//
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 implements the TargetLoweringBase class.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/ADT/BitVector.h"
14 #include "llvm/ADT/STLExtras.h"
15 #include "llvm/ADT/SmallVector.h"
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/Twine.h"
19 #include "llvm/Analysis/Loads.h"
20 #include "llvm/Analysis/TargetTransformInfo.h"
21 #include "llvm/CodeGen/Analysis.h"
22 #include "llvm/CodeGen/ISDOpcodes.h"
23 #include "llvm/CodeGen/MachineBasicBlock.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineInstr.h"
27 #include "llvm/CodeGen/MachineInstrBuilder.h"
28 #include "llvm/CodeGen/MachineMemOperand.h"
29 #include "llvm/CodeGen/MachineOperand.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/RuntimeLibcallUtil.h"
32 #include "llvm/CodeGen/StackMaps.h"
33 #include "llvm/CodeGen/TargetLowering.h"
34 #include "llvm/CodeGen/TargetOpcodes.h"
35 #include "llvm/CodeGen/TargetRegisterInfo.h"
36 #include "llvm/CodeGen/ValueTypes.h"
37 #include "llvm/CodeGenTypes/MachineValueType.h"
38 #include "llvm/IR/Attributes.h"
39 #include "llvm/IR/CallingConv.h"
40 #include "llvm/IR/DataLayout.h"
41 #include "llvm/IR/DerivedTypes.h"
42 #include "llvm/IR/Function.h"
43 #include "llvm/IR/GlobalValue.h"
44 #include "llvm/IR/GlobalVariable.h"
45 #include "llvm/IR/IRBuilder.h"
46 #include "llvm/IR/Module.h"
47 #include "llvm/IR/Type.h"
48 #include "llvm/Support/Casting.h"
49 #include "llvm/Support/CommandLine.h"
50 #include "llvm/Support/Compiler.h"
51 #include "llvm/Support/ErrorHandling.h"
52 #include "llvm/Support/MathExtras.h"
53 #include "llvm/Target/TargetMachine.h"
54 #include "llvm/Target/TargetOptions.h"
55 #include "llvm/TargetParser/Triple.h"
56 #include "llvm/Transforms/Utils/SizeOpts.h"
57 #include <algorithm>
58 #include <cassert>
59 #include <cstdint>
60 #include <cstring>
61 #include <iterator>
62 #include <string>
63 #include <tuple>
64 #include <utility>
65
66 using namespace llvm;
67
68 static cl::opt<bool> JumpIsExpensiveOverride(
69 "jump-is-expensive", cl::init(false),
70 cl::desc("Do not create extra branches to split comparison logic."),
71 cl::Hidden);
72
73 static cl::opt<unsigned> MinimumJumpTableEntries
74 ("min-jump-table-entries", cl::init(4), cl::Hidden,
75 cl::desc("Set minimum number of entries to use a jump table."));
76
77 static cl::opt<unsigned> MaximumJumpTableSize
78 ("max-jump-table-size", cl::init(UINT_MAX), cl::Hidden,
79 cl::desc("Set maximum size of jump tables."));
80
81 /// Minimum jump table density for normal functions.
82 static cl::opt<unsigned>
83 JumpTableDensity("jump-table-density", cl::init(10), cl::Hidden,
84 cl::desc("Minimum density for building a jump table in "
85 "a normal function"));
86
87 /// Minimum jump table density for -Os or -Oz functions.
88 static cl::opt<unsigned> OptsizeJumpTableDensity(
89 "optsize-jump-table-density", cl::init(40), cl::Hidden,
90 cl::desc("Minimum density for building a jump table in "
91 "an optsize function"));
92
93 // FIXME: This option is only to test if the strict fp operation processed
94 // correctly by preventing mutating strict fp operation to normal fp operation
95 // during development. When the backend supports strict float operation, this
96 // option will be meaningless.
97 static cl::opt<bool> DisableStrictNodeMutation("disable-strictnode-mutation",
98 cl::desc("Don't mutate strict-float node to a legalize node"),
99 cl::init(false), cl::Hidden);
100
101 /// GetFPLibCall - Helper to return the right libcall for the given floating
102 /// point type, or UNKNOWN_LIBCALL if there is none.
getFPLibCall(EVT VT,RTLIB::Libcall Call_F32,RTLIB::Libcall Call_F64,RTLIB::Libcall Call_F80,RTLIB::Libcall Call_F128,RTLIB::Libcall Call_PPCF128)103 RTLIB::Libcall RTLIB::getFPLibCall(EVT VT,
104 RTLIB::Libcall Call_F32,
105 RTLIB::Libcall Call_F64,
106 RTLIB::Libcall Call_F80,
107 RTLIB::Libcall Call_F128,
108 RTLIB::Libcall Call_PPCF128) {
109 return
110 VT == MVT::f32 ? Call_F32 :
111 VT == MVT::f64 ? Call_F64 :
112 VT == MVT::f80 ? Call_F80 :
113 VT == MVT::f128 ? Call_F128 :
114 VT == MVT::ppcf128 ? Call_PPCF128 :
115 RTLIB::UNKNOWN_LIBCALL;
116 }
117
118 /// getFPEXT - Return the FPEXT_*_* value for the given types, or
119 /// UNKNOWN_LIBCALL if there is none.
getFPEXT(EVT OpVT,EVT RetVT)120 RTLIB::Libcall RTLIB::getFPEXT(EVT OpVT, EVT RetVT) {
121 if (OpVT == MVT::f16) {
122 if (RetVT == MVT::f32)
123 return FPEXT_F16_F32;
124 if (RetVT == MVT::f64)
125 return FPEXT_F16_F64;
126 if (RetVT == MVT::f80)
127 return FPEXT_F16_F80;
128 if (RetVT == MVT::f128)
129 return FPEXT_F16_F128;
130 } else if (OpVT == MVT::f32) {
131 if (RetVT == MVT::f64)
132 return FPEXT_F32_F64;
133 if (RetVT == MVT::f128)
134 return FPEXT_F32_F128;
135 if (RetVT == MVT::ppcf128)
136 return FPEXT_F32_PPCF128;
137 } else if (OpVT == MVT::f64) {
138 if (RetVT == MVT::f128)
139 return FPEXT_F64_F128;
140 else if (RetVT == MVT::ppcf128)
141 return FPEXT_F64_PPCF128;
142 } else if (OpVT == MVT::f80) {
143 if (RetVT == MVT::f128)
144 return FPEXT_F80_F128;
145 } else if (OpVT == MVT::bf16) {
146 if (RetVT == MVT::f32)
147 return FPEXT_BF16_F32;
148 }
149
150 return UNKNOWN_LIBCALL;
151 }
152
153 /// getFPROUND - Return the FPROUND_*_* value for the given types, or
154 /// UNKNOWN_LIBCALL if there is none.
getFPROUND(EVT OpVT,EVT RetVT)155 RTLIB::Libcall RTLIB::getFPROUND(EVT OpVT, EVT RetVT) {
156 if (RetVT == MVT::f16) {
157 if (OpVT == MVT::f32)
158 return FPROUND_F32_F16;
159 if (OpVT == MVT::f64)
160 return FPROUND_F64_F16;
161 if (OpVT == MVT::f80)
162 return FPROUND_F80_F16;
163 if (OpVT == MVT::f128)
164 return FPROUND_F128_F16;
165 if (OpVT == MVT::ppcf128)
166 return FPROUND_PPCF128_F16;
167 } else if (RetVT == MVT::bf16) {
168 if (OpVT == MVT::f32)
169 return FPROUND_F32_BF16;
170 if (OpVT == MVT::f64)
171 return FPROUND_F64_BF16;
172 } else if (RetVT == MVT::f32) {
173 if (OpVT == MVT::f64)
174 return FPROUND_F64_F32;
175 if (OpVT == MVT::f80)
176 return FPROUND_F80_F32;
177 if (OpVT == MVT::f128)
178 return FPROUND_F128_F32;
179 if (OpVT == MVT::ppcf128)
180 return FPROUND_PPCF128_F32;
181 } else if (RetVT == MVT::f64) {
182 if (OpVT == MVT::f80)
183 return FPROUND_F80_F64;
184 if (OpVT == MVT::f128)
185 return FPROUND_F128_F64;
186 if (OpVT == MVT::ppcf128)
187 return FPROUND_PPCF128_F64;
188 } else if (RetVT == MVT::f80) {
189 if (OpVT == MVT::f128)
190 return FPROUND_F128_F80;
191 }
192
193 return UNKNOWN_LIBCALL;
194 }
195
196 /// getFPTOSINT - Return the FPTOSINT_*_* value for the given types, or
197 /// UNKNOWN_LIBCALL if there is none.
getFPTOSINT(EVT OpVT,EVT RetVT)198 RTLIB::Libcall RTLIB::getFPTOSINT(EVT OpVT, EVT RetVT) {
199 if (OpVT == MVT::f16) {
200 if (RetVT == MVT::i32)
201 return FPTOSINT_F16_I32;
202 if (RetVT == MVT::i64)
203 return FPTOSINT_F16_I64;
204 if (RetVT == MVT::i128)
205 return FPTOSINT_F16_I128;
206 } else if (OpVT == MVT::f32) {
207 if (RetVT == MVT::i32)
208 return FPTOSINT_F32_I32;
209 if (RetVT == MVT::i64)
210 return FPTOSINT_F32_I64;
211 if (RetVT == MVT::i128)
212 return FPTOSINT_F32_I128;
213 } else if (OpVT == MVT::f64) {
214 if (RetVT == MVT::i32)
215 return FPTOSINT_F64_I32;
216 if (RetVT == MVT::i64)
217 return FPTOSINT_F64_I64;
218 if (RetVT == MVT::i128)
219 return FPTOSINT_F64_I128;
220 } else if (OpVT == MVT::f80) {
221 if (RetVT == MVT::i32)
222 return FPTOSINT_F80_I32;
223 if (RetVT == MVT::i64)
224 return FPTOSINT_F80_I64;
225 if (RetVT == MVT::i128)
226 return FPTOSINT_F80_I128;
227 } else if (OpVT == MVT::f128) {
228 if (RetVT == MVT::i32)
229 return FPTOSINT_F128_I32;
230 if (RetVT == MVT::i64)
231 return FPTOSINT_F128_I64;
232 if (RetVT == MVT::i128)
233 return FPTOSINT_F128_I128;
234 } else if (OpVT == MVT::ppcf128) {
235 if (RetVT == MVT::i32)
236 return FPTOSINT_PPCF128_I32;
237 if (RetVT == MVT::i64)
238 return FPTOSINT_PPCF128_I64;
239 if (RetVT == MVT::i128)
240 return FPTOSINT_PPCF128_I128;
241 }
242 return UNKNOWN_LIBCALL;
243 }
244
245 /// getFPTOUINT - Return the FPTOUINT_*_* value for the given types, or
246 /// UNKNOWN_LIBCALL if there is none.
getFPTOUINT(EVT OpVT,EVT RetVT)247 RTLIB::Libcall RTLIB::getFPTOUINT(EVT OpVT, EVT RetVT) {
248 if (OpVT == MVT::f16) {
249 if (RetVT == MVT::i32)
250 return FPTOUINT_F16_I32;
251 if (RetVT == MVT::i64)
252 return FPTOUINT_F16_I64;
253 if (RetVT == MVT::i128)
254 return FPTOUINT_F16_I128;
255 } else if (OpVT == MVT::f32) {
256 if (RetVT == MVT::i32)
257 return FPTOUINT_F32_I32;
258 if (RetVT == MVT::i64)
259 return FPTOUINT_F32_I64;
260 if (RetVT == MVT::i128)
261 return FPTOUINT_F32_I128;
262 } else if (OpVT == MVT::f64) {
263 if (RetVT == MVT::i32)
264 return FPTOUINT_F64_I32;
265 if (RetVT == MVT::i64)
266 return FPTOUINT_F64_I64;
267 if (RetVT == MVT::i128)
268 return FPTOUINT_F64_I128;
269 } else if (OpVT == MVT::f80) {
270 if (RetVT == MVT::i32)
271 return FPTOUINT_F80_I32;
272 if (RetVT == MVT::i64)
273 return FPTOUINT_F80_I64;
274 if (RetVT == MVT::i128)
275 return FPTOUINT_F80_I128;
276 } else if (OpVT == MVT::f128) {
277 if (RetVT == MVT::i32)
278 return FPTOUINT_F128_I32;
279 if (RetVT == MVT::i64)
280 return FPTOUINT_F128_I64;
281 if (RetVT == MVT::i128)
282 return FPTOUINT_F128_I128;
283 } else if (OpVT == MVT::ppcf128) {
284 if (RetVT == MVT::i32)
285 return FPTOUINT_PPCF128_I32;
286 if (RetVT == MVT::i64)
287 return FPTOUINT_PPCF128_I64;
288 if (RetVT == MVT::i128)
289 return FPTOUINT_PPCF128_I128;
290 }
291 return UNKNOWN_LIBCALL;
292 }
293
294 /// getSINTTOFP - Return the SINTTOFP_*_* value for the given types, or
295 /// UNKNOWN_LIBCALL if there is none.
getSINTTOFP(EVT OpVT,EVT RetVT)296 RTLIB::Libcall RTLIB::getSINTTOFP(EVT OpVT, EVT RetVT) {
297 if (OpVT == MVT::i32) {
298 if (RetVT == MVT::f16)
299 return SINTTOFP_I32_F16;
300 if (RetVT == MVT::f32)
301 return SINTTOFP_I32_F32;
302 if (RetVT == MVT::f64)
303 return SINTTOFP_I32_F64;
304 if (RetVT == MVT::f80)
305 return SINTTOFP_I32_F80;
306 if (RetVT == MVT::f128)
307 return SINTTOFP_I32_F128;
308 if (RetVT == MVT::ppcf128)
309 return SINTTOFP_I32_PPCF128;
310 } else if (OpVT == MVT::i64) {
311 if (RetVT == MVT::f16)
312 return SINTTOFP_I64_F16;
313 if (RetVT == MVT::f32)
314 return SINTTOFP_I64_F32;
315 if (RetVT == MVT::f64)
316 return SINTTOFP_I64_F64;
317 if (RetVT == MVT::f80)
318 return SINTTOFP_I64_F80;
319 if (RetVT == MVT::f128)
320 return SINTTOFP_I64_F128;
321 if (RetVT == MVT::ppcf128)
322 return SINTTOFP_I64_PPCF128;
323 } else if (OpVT == MVT::i128) {
324 if (RetVT == MVT::f16)
325 return SINTTOFP_I128_F16;
326 if (RetVT == MVT::f32)
327 return SINTTOFP_I128_F32;
328 if (RetVT == MVT::f64)
329 return SINTTOFP_I128_F64;
330 if (RetVT == MVT::f80)
331 return SINTTOFP_I128_F80;
332 if (RetVT == MVT::f128)
333 return SINTTOFP_I128_F128;
334 if (RetVT == MVT::ppcf128)
335 return SINTTOFP_I128_PPCF128;
336 }
337 return UNKNOWN_LIBCALL;
338 }
339
340 /// getUINTTOFP - Return the UINTTOFP_*_* value for the given types, or
341 /// UNKNOWN_LIBCALL if there is none.
getUINTTOFP(EVT OpVT,EVT RetVT)342 RTLIB::Libcall RTLIB::getUINTTOFP(EVT OpVT, EVT RetVT) {
343 if (OpVT == MVT::i32) {
344 if (RetVT == MVT::f16)
345 return UINTTOFP_I32_F16;
346 if (RetVT == MVT::f32)
347 return UINTTOFP_I32_F32;
348 if (RetVT == MVT::f64)
349 return UINTTOFP_I32_F64;
350 if (RetVT == MVT::f80)
351 return UINTTOFP_I32_F80;
352 if (RetVT == MVT::f128)
353 return UINTTOFP_I32_F128;
354 if (RetVT == MVT::ppcf128)
355 return UINTTOFP_I32_PPCF128;
356 } else if (OpVT == MVT::i64) {
357 if (RetVT == MVT::f16)
358 return UINTTOFP_I64_F16;
359 if (RetVT == MVT::f32)
360 return UINTTOFP_I64_F32;
361 if (RetVT == MVT::f64)
362 return UINTTOFP_I64_F64;
363 if (RetVT == MVT::f80)
364 return UINTTOFP_I64_F80;
365 if (RetVT == MVT::f128)
366 return UINTTOFP_I64_F128;
367 if (RetVT == MVT::ppcf128)
368 return UINTTOFP_I64_PPCF128;
369 } else if (OpVT == MVT::i128) {
370 if (RetVT == MVT::f16)
371 return UINTTOFP_I128_F16;
372 if (RetVT == MVT::f32)
373 return UINTTOFP_I128_F32;
374 if (RetVT == MVT::f64)
375 return UINTTOFP_I128_F64;
376 if (RetVT == MVT::f80)
377 return UINTTOFP_I128_F80;
378 if (RetVT == MVT::f128)
379 return UINTTOFP_I128_F128;
380 if (RetVT == MVT::ppcf128)
381 return UINTTOFP_I128_PPCF128;
382 }
383 return UNKNOWN_LIBCALL;
384 }
385
getPOWI(EVT RetVT)386 RTLIB::Libcall RTLIB::getPOWI(EVT RetVT) {
387 return getFPLibCall(RetVT, POWI_F32, POWI_F64, POWI_F80, POWI_F128,
388 POWI_PPCF128);
389 }
390
getLDEXP(EVT RetVT)391 RTLIB::Libcall RTLIB::getLDEXP(EVT RetVT) {
392 return getFPLibCall(RetVT, LDEXP_F32, LDEXP_F64, LDEXP_F80, LDEXP_F128,
393 LDEXP_PPCF128);
394 }
395
getFREXP(EVT RetVT)396 RTLIB::Libcall RTLIB::getFREXP(EVT RetVT) {
397 return getFPLibCall(RetVT, FREXP_F32, FREXP_F64, FREXP_F80, FREXP_F128,
398 FREXP_PPCF128);
399 }
400
getOutlineAtomicHelper(const Libcall (& LC)[5][4],AtomicOrdering Order,uint64_t MemSize)401 RTLIB::Libcall RTLIB::getOutlineAtomicHelper(const Libcall (&LC)[5][4],
402 AtomicOrdering Order,
403 uint64_t MemSize) {
404 unsigned ModeN, ModelN;
405 switch (MemSize) {
406 case 1:
407 ModeN = 0;
408 break;
409 case 2:
410 ModeN = 1;
411 break;
412 case 4:
413 ModeN = 2;
414 break;
415 case 8:
416 ModeN = 3;
417 break;
418 case 16:
419 ModeN = 4;
420 break;
421 default:
422 return RTLIB::UNKNOWN_LIBCALL;
423 }
424
425 switch (Order) {
426 case AtomicOrdering::Monotonic:
427 ModelN = 0;
428 break;
429 case AtomicOrdering::Acquire:
430 ModelN = 1;
431 break;
432 case AtomicOrdering::Release:
433 ModelN = 2;
434 break;
435 case AtomicOrdering::AcquireRelease:
436 case AtomicOrdering::SequentiallyConsistent:
437 ModelN = 3;
438 break;
439 default:
440 return UNKNOWN_LIBCALL;
441 }
442
443 return LC[ModeN][ModelN];
444 }
445
getOUTLINE_ATOMIC(unsigned Opc,AtomicOrdering Order,MVT VT)446 RTLIB::Libcall RTLIB::getOUTLINE_ATOMIC(unsigned Opc, AtomicOrdering Order,
447 MVT VT) {
448 if (!VT.isScalarInteger())
449 return UNKNOWN_LIBCALL;
450 uint64_t MemSize = VT.getScalarSizeInBits() / 8;
451
452 #define LCALLS(A, B) \
453 { A##B##_RELAX, A##B##_ACQ, A##B##_REL, A##B##_ACQ_REL }
454 #define LCALL5(A) \
455 LCALLS(A, 1), LCALLS(A, 2), LCALLS(A, 4), LCALLS(A, 8), LCALLS(A, 16)
456 switch (Opc) {
457 case ISD::ATOMIC_CMP_SWAP: {
458 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_CAS)};
459 return getOutlineAtomicHelper(LC, Order, MemSize);
460 }
461 case ISD::ATOMIC_SWAP: {
462 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_SWP)};
463 return getOutlineAtomicHelper(LC, Order, MemSize);
464 }
465 case ISD::ATOMIC_LOAD_ADD: {
466 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_LDADD)};
467 return getOutlineAtomicHelper(LC, Order, MemSize);
468 }
469 case ISD::ATOMIC_LOAD_OR: {
470 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_LDSET)};
471 return getOutlineAtomicHelper(LC, Order, MemSize);
472 }
473 case ISD::ATOMIC_LOAD_CLR: {
474 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_LDCLR)};
475 return getOutlineAtomicHelper(LC, Order, MemSize);
476 }
477 case ISD::ATOMIC_LOAD_XOR: {
478 const Libcall LC[5][4] = {LCALL5(OUTLINE_ATOMIC_LDEOR)};
479 return getOutlineAtomicHelper(LC, Order, MemSize);
480 }
481 default:
482 return UNKNOWN_LIBCALL;
483 }
484 #undef LCALLS
485 #undef LCALL5
486 }
487
getSYNC(unsigned Opc,MVT VT)488 RTLIB::Libcall RTLIB::getSYNC(unsigned Opc, MVT VT) {
489 #define OP_TO_LIBCALL(Name, Enum) \
490 case Name: \
491 switch (VT.SimpleTy) { \
492 default: \
493 return UNKNOWN_LIBCALL; \
494 case MVT::i8: \
495 return Enum##_1; \
496 case MVT::i16: \
497 return Enum##_2; \
498 case MVT::i32: \
499 return Enum##_4; \
500 case MVT::i64: \
501 return Enum##_8; \
502 case MVT::i128: \
503 return Enum##_16; \
504 }
505
506 switch (Opc) {
507 OP_TO_LIBCALL(ISD::ATOMIC_SWAP, SYNC_LOCK_TEST_AND_SET)
508 OP_TO_LIBCALL(ISD::ATOMIC_CMP_SWAP, SYNC_VAL_COMPARE_AND_SWAP)
509 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_ADD, SYNC_FETCH_AND_ADD)
510 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_SUB, SYNC_FETCH_AND_SUB)
511 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_AND, SYNC_FETCH_AND_AND)
512 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_OR, SYNC_FETCH_AND_OR)
513 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_XOR, SYNC_FETCH_AND_XOR)
514 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_NAND, SYNC_FETCH_AND_NAND)
515 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_MAX, SYNC_FETCH_AND_MAX)
516 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_UMAX, SYNC_FETCH_AND_UMAX)
517 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_MIN, SYNC_FETCH_AND_MIN)
518 OP_TO_LIBCALL(ISD::ATOMIC_LOAD_UMIN, SYNC_FETCH_AND_UMIN)
519 }
520
521 #undef OP_TO_LIBCALL
522
523 return UNKNOWN_LIBCALL;
524 }
525
getMEMCPY_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize)526 RTLIB::Libcall RTLIB::getMEMCPY_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
527 switch (ElementSize) {
528 case 1:
529 return MEMCPY_ELEMENT_UNORDERED_ATOMIC_1;
530 case 2:
531 return MEMCPY_ELEMENT_UNORDERED_ATOMIC_2;
532 case 4:
533 return MEMCPY_ELEMENT_UNORDERED_ATOMIC_4;
534 case 8:
535 return MEMCPY_ELEMENT_UNORDERED_ATOMIC_8;
536 case 16:
537 return MEMCPY_ELEMENT_UNORDERED_ATOMIC_16;
538 default:
539 return UNKNOWN_LIBCALL;
540 }
541 }
542
getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize)543 RTLIB::Libcall RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
544 switch (ElementSize) {
545 case 1:
546 return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_1;
547 case 2:
548 return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_2;
549 case 4:
550 return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_4;
551 case 8:
552 return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_8;
553 case 16:
554 return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_16;
555 default:
556 return UNKNOWN_LIBCALL;
557 }
558 }
559
getMEMSET_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize)560 RTLIB::Libcall RTLIB::getMEMSET_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
561 switch (ElementSize) {
562 case 1:
563 return MEMSET_ELEMENT_UNORDERED_ATOMIC_1;
564 case 2:
565 return MEMSET_ELEMENT_UNORDERED_ATOMIC_2;
566 case 4:
567 return MEMSET_ELEMENT_UNORDERED_ATOMIC_4;
568 case 8:
569 return MEMSET_ELEMENT_UNORDERED_ATOMIC_8;
570 case 16:
571 return MEMSET_ELEMENT_UNORDERED_ATOMIC_16;
572 default:
573 return UNKNOWN_LIBCALL;
574 }
575 }
576
initCmpLibcallCCs(ISD::CondCode * CmpLibcallCCs)577 void RTLIB::initCmpLibcallCCs(ISD::CondCode *CmpLibcallCCs) {
578 std::fill(CmpLibcallCCs, CmpLibcallCCs + RTLIB::UNKNOWN_LIBCALL,
579 ISD::SETCC_INVALID);
580 CmpLibcallCCs[RTLIB::OEQ_F32] = ISD::SETEQ;
581 CmpLibcallCCs[RTLIB::OEQ_F64] = ISD::SETEQ;
582 CmpLibcallCCs[RTLIB::OEQ_F128] = ISD::SETEQ;
583 CmpLibcallCCs[RTLIB::OEQ_PPCF128] = ISD::SETEQ;
584 CmpLibcallCCs[RTLIB::UNE_F32] = ISD::SETNE;
585 CmpLibcallCCs[RTLIB::UNE_F64] = ISD::SETNE;
586 CmpLibcallCCs[RTLIB::UNE_F128] = ISD::SETNE;
587 CmpLibcallCCs[RTLIB::UNE_PPCF128] = ISD::SETNE;
588 CmpLibcallCCs[RTLIB::OGE_F32] = ISD::SETGE;
589 CmpLibcallCCs[RTLIB::OGE_F64] = ISD::SETGE;
590 CmpLibcallCCs[RTLIB::OGE_F128] = ISD::SETGE;
591 CmpLibcallCCs[RTLIB::OGE_PPCF128] = ISD::SETGE;
592 CmpLibcallCCs[RTLIB::OLT_F32] = ISD::SETLT;
593 CmpLibcallCCs[RTLIB::OLT_F64] = ISD::SETLT;
594 CmpLibcallCCs[RTLIB::OLT_F128] = ISD::SETLT;
595 CmpLibcallCCs[RTLIB::OLT_PPCF128] = ISD::SETLT;
596 CmpLibcallCCs[RTLIB::OLE_F32] = ISD::SETLE;
597 CmpLibcallCCs[RTLIB::OLE_F64] = ISD::SETLE;
598 CmpLibcallCCs[RTLIB::OLE_F128] = ISD::SETLE;
599 CmpLibcallCCs[RTLIB::OLE_PPCF128] = ISD::SETLE;
600 CmpLibcallCCs[RTLIB::OGT_F32] = ISD::SETGT;
601 CmpLibcallCCs[RTLIB::OGT_F64] = ISD::SETGT;
602 CmpLibcallCCs[RTLIB::OGT_F128] = ISD::SETGT;
603 CmpLibcallCCs[RTLIB::OGT_PPCF128] = ISD::SETGT;
604 CmpLibcallCCs[RTLIB::UO_F32] = ISD::SETNE;
605 CmpLibcallCCs[RTLIB::UO_F64] = ISD::SETNE;
606 CmpLibcallCCs[RTLIB::UO_F128] = ISD::SETNE;
607 CmpLibcallCCs[RTLIB::UO_PPCF128] = ISD::SETNE;
608 }
609
610 /// NOTE: The TargetMachine owns TLOF.
TargetLoweringBase(const TargetMachine & tm)611 TargetLoweringBase::TargetLoweringBase(const TargetMachine &tm)
612 : TM(tm), Libcalls(TM.getTargetTriple()) {
613 initActions();
614
615 // Perform these initializations only once.
616 MaxStoresPerMemset = MaxStoresPerMemcpy = MaxStoresPerMemmove =
617 MaxLoadsPerMemcmp = 8;
618 MaxGluedStoresPerMemcpy = 0;
619 MaxStoresPerMemsetOptSize = MaxStoresPerMemcpyOptSize =
620 MaxStoresPerMemmoveOptSize = MaxLoadsPerMemcmpOptSize = 4;
621 HasMultipleConditionRegisters = false;
622 HasExtractBitsInsn = false;
623 JumpIsExpensive = JumpIsExpensiveOverride;
624 PredictableSelectIsExpensive = false;
625 EnableExtLdPromotion = false;
626 StackPointerRegisterToSaveRestore = 0;
627 BooleanContents = UndefinedBooleanContent;
628 BooleanFloatContents = UndefinedBooleanContent;
629 BooleanVectorContents = UndefinedBooleanContent;
630 SchedPreferenceInfo = Sched::ILP;
631 GatherAllAliasesMaxDepth = 18;
632 IsStrictFPEnabled = DisableStrictNodeMutation;
633 MaxBytesForAlignment = 0;
634 MaxAtomicSizeInBitsSupported = 0;
635
636 // Assume that even with libcalls, no target supports wider than 128 bit
637 // division.
638 MaxDivRemBitWidthSupported = 128;
639
640 MaxLargeFPConvertBitWidthSupported = llvm::IntegerType::MAX_INT_BITS;
641
642 MinCmpXchgSizeInBits = 0;
643 SupportsUnalignedAtomics = false;
644
645 RTLIB::initCmpLibcallCCs(CmpLibcallCCs);
646 }
647
initActions()648 void TargetLoweringBase::initActions() {
649 // All operations default to being supported.
650 memset(OpActions, 0, sizeof(OpActions));
651 memset(LoadExtActions, 0, sizeof(LoadExtActions));
652 memset(TruncStoreActions, 0, sizeof(TruncStoreActions));
653 memset(IndexedModeActions, 0, sizeof(IndexedModeActions));
654 memset(CondCodeActions, 0, sizeof(CondCodeActions));
655 std::fill(std::begin(RegClassForVT), std::end(RegClassForVT), nullptr);
656 std::fill(std::begin(TargetDAGCombineArray),
657 std::end(TargetDAGCombineArray), 0);
658
659 // Let extending atomic loads be unsupported by default.
660 for (MVT ValVT : MVT::all_valuetypes())
661 for (MVT MemVT : MVT::all_valuetypes())
662 setAtomicLoadExtAction({ISD::SEXTLOAD, ISD::ZEXTLOAD}, ValVT, MemVT,
663 Expand);
664
665 // We're somewhat special casing MVT::i2 and MVT::i4. Ideally we want to
666 // remove this and targets should individually set these types if not legal.
667 for (ISD::NodeType NT : enum_seq(ISD::DELETED_NODE, ISD::BUILTIN_OP_END,
668 force_iteration_on_noniterable_enum)) {
669 for (MVT VT : {MVT::i2, MVT::i4})
670 OpActions[(unsigned)VT.SimpleTy][NT] = Expand;
671 }
672 for (MVT AVT : MVT::all_valuetypes()) {
673 for (MVT VT : {MVT::i2, MVT::i4, MVT::v128i2, MVT::v64i4}) {
674 setTruncStoreAction(AVT, VT, Expand);
675 setLoadExtAction(ISD::EXTLOAD, AVT, VT, Expand);
676 setLoadExtAction(ISD::ZEXTLOAD, AVT, VT, Expand);
677 }
678 }
679 for (unsigned IM = (unsigned)ISD::PRE_INC;
680 IM != (unsigned)ISD::LAST_INDEXED_MODE; ++IM) {
681 for (MVT VT : {MVT::i2, MVT::i4}) {
682 setIndexedLoadAction(IM, VT, Expand);
683 setIndexedStoreAction(IM, VT, Expand);
684 setIndexedMaskedLoadAction(IM, VT, Expand);
685 setIndexedMaskedStoreAction(IM, VT, Expand);
686 }
687 }
688
689 for (MVT VT : MVT::fp_valuetypes()) {
690 MVT IntVT = MVT::getIntegerVT(VT.getFixedSizeInBits());
691 if (IntVT.isValid()) {
692 setOperationAction(ISD::ATOMIC_SWAP, VT, Promote);
693 AddPromotedToType(ISD::ATOMIC_SWAP, VT, IntVT);
694 }
695 }
696
697 // Set default actions for various operations.
698 for (MVT VT : MVT::all_valuetypes()) {
699 // Default all indexed load / store to expand.
700 for (unsigned IM = (unsigned)ISD::PRE_INC;
701 IM != (unsigned)ISD::LAST_INDEXED_MODE; ++IM) {
702 setIndexedLoadAction(IM, VT, Expand);
703 setIndexedStoreAction(IM, VT, Expand);
704 setIndexedMaskedLoadAction(IM, VT, Expand);
705 setIndexedMaskedStoreAction(IM, VT, Expand);
706 }
707
708 // Most backends expect to see the node which just returns the value loaded.
709 setOperationAction(ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS, VT, Expand);
710
711 // These operations default to expand.
712 setOperationAction({ISD::FGETSIGN, ISD::CONCAT_VECTORS,
713 ISD::FMINNUM, ISD::FMAXNUM,
714 ISD::FMINNUM_IEEE, ISD::FMAXNUM_IEEE,
715 ISD::FMINIMUM, ISD::FMAXIMUM,
716 ISD::FMAD, ISD::SMIN,
717 ISD::SMAX, ISD::UMIN,
718 ISD::UMAX, ISD::ABS,
719 ISD::FSHL, ISD::FSHR,
720 ISD::SADDSAT, ISD::UADDSAT,
721 ISD::SSUBSAT, ISD::USUBSAT,
722 ISD::SSHLSAT, ISD::USHLSAT,
723 ISD::SMULFIX, ISD::SMULFIXSAT,
724 ISD::UMULFIX, ISD::UMULFIXSAT,
725 ISD::SDIVFIX, ISD::SDIVFIXSAT,
726 ISD::UDIVFIX, ISD::UDIVFIXSAT,
727 ISD::FP_TO_SINT_SAT, ISD::FP_TO_UINT_SAT,
728 ISD::IS_FPCLASS},
729 VT, Expand);
730
731 // Overflow operations default to expand
732 setOperationAction({ISD::SADDO, ISD::SSUBO, ISD::UADDO, ISD::USUBO,
733 ISD::SMULO, ISD::UMULO},
734 VT, Expand);
735
736 // Carry-using overflow operations default to expand.
737 setOperationAction({ISD::UADDO_CARRY, ISD::USUBO_CARRY, ISD::SETCCCARRY,
738 ISD::SADDO_CARRY, ISD::SSUBO_CARRY},
739 VT, Expand);
740
741 // ADDC/ADDE/SUBC/SUBE default to expand.
742 setOperationAction({ISD::ADDC, ISD::ADDE, ISD::SUBC, ISD::SUBE}, VT,
743 Expand);
744
745 // [US]CMP default to expand
746 setOperationAction({ISD::UCMP, ISD::SCMP}, VT, Expand);
747
748 // Halving adds
749 setOperationAction(
750 {ISD::AVGFLOORS, ISD::AVGFLOORU, ISD::AVGCEILS, ISD::AVGCEILU}, VT,
751 Expand);
752
753 // Absolute difference
754 setOperationAction({ISD::ABDS, ISD::ABDU}, VT, Expand);
755
756 // These default to Expand so they will be expanded to CTLZ/CTTZ by default.
757 setOperationAction({ISD::CTLZ_ZERO_UNDEF, ISD::CTTZ_ZERO_UNDEF}, VT,
758 Expand);
759
760 setOperationAction({ISD::BITREVERSE, ISD::PARITY}, VT, Expand);
761
762 // These library functions default to expand.
763 setOperationAction({ISD::FROUND, ISD::FPOWI, ISD::FLDEXP, ISD::FFREXP}, VT,
764 Expand);
765
766 // These operations default to expand for vector types.
767 if (VT.isVector())
768 setOperationAction(
769 {ISD::FCOPYSIGN, ISD::SIGN_EXTEND_INREG, ISD::ANY_EXTEND_VECTOR_INREG,
770 ISD::SIGN_EXTEND_VECTOR_INREG, ISD::ZERO_EXTEND_VECTOR_INREG,
771 ISD::SPLAT_VECTOR, ISD::LRINT, ISD::LLRINT, ISD::FTAN, ISD::FACOS,
772 ISD::FASIN, ISD::FATAN, ISD::FCOSH, ISD::FSINH, ISD::FTANH},
773 VT, Expand);
774
775 // Constrained floating-point operations default to expand.
776 #define DAG_INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC, DAGN) \
777 setOperationAction(ISD::STRICT_##DAGN, VT, Expand);
778 #include "llvm/IR/ConstrainedOps.def"
779
780 // For most targets @llvm.get.dynamic.area.offset just returns 0.
781 setOperationAction(ISD::GET_DYNAMIC_AREA_OFFSET, VT, Expand);
782
783 // Vector reduction default to expand.
784 setOperationAction(
785 {ISD::VECREDUCE_FADD, ISD::VECREDUCE_FMUL, ISD::VECREDUCE_ADD,
786 ISD::VECREDUCE_MUL, ISD::VECREDUCE_AND, ISD::VECREDUCE_OR,
787 ISD::VECREDUCE_XOR, ISD::VECREDUCE_SMAX, ISD::VECREDUCE_SMIN,
788 ISD::VECREDUCE_UMAX, ISD::VECREDUCE_UMIN, ISD::VECREDUCE_FMAX,
789 ISD::VECREDUCE_FMIN, ISD::VECREDUCE_FMAXIMUM, ISD::VECREDUCE_FMINIMUM,
790 ISD::VECREDUCE_SEQ_FADD, ISD::VECREDUCE_SEQ_FMUL},
791 VT, Expand);
792
793 // Named vector shuffles default to expand.
794 setOperationAction(ISD::VECTOR_SPLICE, VT, Expand);
795
796 // Only some target support this vector operation. Most need to expand it.
797 setOperationAction(ISD::VECTOR_COMPRESS, VT, Expand);
798
799 // VP operations default to expand.
800 #define BEGIN_REGISTER_VP_SDNODE(SDOPC, ...) \
801 setOperationAction(ISD::SDOPC, VT, Expand);
802 #include "llvm/IR/VPIntrinsics.def"
803
804 // FP environment operations default to expand.
805 setOperationAction(ISD::GET_FPENV, VT, Expand);
806 setOperationAction(ISD::SET_FPENV, VT, Expand);
807 setOperationAction(ISD::RESET_FPENV, VT, Expand);
808 }
809
810 // Most targets ignore the @llvm.prefetch intrinsic.
811 setOperationAction(ISD::PREFETCH, MVT::Other, Expand);
812
813 // Most targets also ignore the @llvm.readcyclecounter intrinsic.
814 setOperationAction(ISD::READCYCLECOUNTER, MVT::i64, Expand);
815
816 // Most targets also ignore the @llvm.readsteadycounter intrinsic.
817 setOperationAction(ISD::READSTEADYCOUNTER, MVT::i64, Expand);
818
819 // ConstantFP nodes default to expand. Targets can either change this to
820 // Legal, in which case all fp constants are legal, or use isFPImmLegal()
821 // to optimize expansions for certain constants.
822 setOperationAction(ISD::ConstantFP,
823 {MVT::bf16, MVT::f16, MVT::f32, MVT::f64, MVT::f80, MVT::f128},
824 Expand);
825
826 // These library functions default to expand.
827 setOperationAction({ISD::FCBRT, ISD::FLOG, ISD::FLOG2, ISD::FLOG10,
828 ISD::FEXP, ISD::FEXP2, ISD::FEXP10, ISD::FFLOOR,
829 ISD::FNEARBYINT, ISD::FCEIL, ISD::FRINT, ISD::FTRUNC,
830 ISD::LROUND, ISD::LLROUND, ISD::LRINT, ISD::LLRINT,
831 ISD::FROUNDEVEN, ISD::FTAN, ISD::FACOS, ISD::FASIN,
832 ISD::FATAN, ISD::FCOSH, ISD::FSINH, ISD::FTANH},
833 {MVT::f32, MVT::f64, MVT::f128}, Expand);
834
835 setOperationAction({ISD::FTAN, ISD::FACOS, ISD::FASIN, ISD::FATAN, ISD::FCOSH,
836 ISD::FSINH, ISD::FTANH},
837 MVT::f16, Promote);
838 // Default ISD::TRAP to expand (which turns it into abort).
839 setOperationAction(ISD::TRAP, MVT::Other, Expand);
840
841 // On most systems, DEBUGTRAP and TRAP have no difference. The "Expand"
842 // here is to inform DAG Legalizer to replace DEBUGTRAP with TRAP.
843 setOperationAction(ISD::DEBUGTRAP, MVT::Other, Expand);
844
845 setOperationAction(ISD::UBSANTRAP, MVT::Other, Expand);
846
847 setOperationAction(ISD::GET_FPENV_MEM, MVT::Other, Expand);
848 setOperationAction(ISD::SET_FPENV_MEM, MVT::Other, Expand);
849
850 for (MVT VT : {MVT::i8, MVT::i16, MVT::i32, MVT::i64}) {
851 setOperationAction(ISD::GET_FPMODE, VT, Expand);
852 setOperationAction(ISD::SET_FPMODE, VT, Expand);
853 }
854 setOperationAction(ISD::RESET_FPMODE, MVT::Other, Expand);
855
856 // This one by default will call __clear_cache unless the target
857 // wants something different.
858 setOperationAction(ISD::CLEAR_CACHE, MVT::Other, LibCall);
859 }
860
getScalarShiftAmountTy(const DataLayout & DL,EVT) const861 MVT TargetLoweringBase::getScalarShiftAmountTy(const DataLayout &DL,
862 EVT) const {
863 return MVT::getIntegerVT(DL.getPointerSizeInBits(0));
864 }
865
getShiftAmountTy(EVT LHSTy,const DataLayout & DL) const866 EVT TargetLoweringBase::getShiftAmountTy(EVT LHSTy,
867 const DataLayout &DL) const {
868 assert(LHSTy.isInteger() && "Shift amount is not an integer type!");
869 if (LHSTy.isVector())
870 return LHSTy;
871 MVT ShiftVT = getScalarShiftAmountTy(DL, LHSTy);
872 // If any possible shift value won't fit in the prefered type, just use
873 // something safe. Assume it will be legalized when the shift is expanded.
874 if (ShiftVT.getSizeInBits() < Log2_32_Ceil(LHSTy.getSizeInBits()))
875 ShiftVT = MVT::i32;
876 assert(ShiftVT.getSizeInBits() >= Log2_32_Ceil(LHSTy.getSizeInBits()) &&
877 "ShiftVT is still too small!");
878 return ShiftVT;
879 }
880
canOpTrap(unsigned Op,EVT VT) const881 bool TargetLoweringBase::canOpTrap(unsigned Op, EVT VT) const {
882 assert(isTypeLegal(VT));
883 switch (Op) {
884 default:
885 return false;
886 case ISD::SDIV:
887 case ISD::UDIV:
888 case ISD::SREM:
889 case ISD::UREM:
890 return true;
891 }
892 }
893
isFreeAddrSpaceCast(unsigned SrcAS,unsigned DestAS) const894 bool TargetLoweringBase::isFreeAddrSpaceCast(unsigned SrcAS,
895 unsigned DestAS) const {
896 return TM.isNoopAddrSpaceCast(SrcAS, DestAS);
897 }
898
getBitWidthForCttzElements(Type * RetTy,ElementCount EC,bool ZeroIsPoison,const ConstantRange * VScaleRange) const899 unsigned TargetLoweringBase::getBitWidthForCttzElements(
900 Type *RetTy, ElementCount EC, bool ZeroIsPoison,
901 const ConstantRange *VScaleRange) const {
902 // Find the smallest "sensible" element type to use for the expansion.
903 ConstantRange CR(APInt(64, EC.getKnownMinValue()));
904 if (EC.isScalable())
905 CR = CR.umul_sat(*VScaleRange);
906
907 if (ZeroIsPoison)
908 CR = CR.subtract(APInt(64, 1));
909
910 unsigned EltWidth = RetTy->getScalarSizeInBits();
911 EltWidth = std::min(EltWidth, (unsigned)CR.getActiveBits());
912 EltWidth = std::max(llvm::bit_ceil(EltWidth), (unsigned)8);
913
914 return EltWidth;
915 }
916
setJumpIsExpensive(bool isExpensive)917 void TargetLoweringBase::setJumpIsExpensive(bool isExpensive) {
918 // If the command-line option was specified, ignore this request.
919 if (!JumpIsExpensiveOverride.getNumOccurrences())
920 JumpIsExpensive = isExpensive;
921 }
922
923 TargetLoweringBase::LegalizeKind
getTypeConversion(LLVMContext & Context,EVT VT) const924 TargetLoweringBase::getTypeConversion(LLVMContext &Context, EVT VT) const {
925 // If this is a simple type, use the ComputeRegisterProp mechanism.
926 if (VT.isSimple()) {
927 MVT SVT = VT.getSimpleVT();
928 assert((unsigned)SVT.SimpleTy < std::size(TransformToType));
929 MVT NVT = TransformToType[SVT.SimpleTy];
930 LegalizeTypeAction LA = ValueTypeActions.getTypeAction(SVT);
931
932 assert((LA == TypeLegal || LA == TypeSoftenFloat ||
933 LA == TypeSoftPromoteHalf ||
934 (NVT.isVector() ||
935 ValueTypeActions.getTypeAction(NVT) != TypePromoteInteger)) &&
936 "Promote may not follow Expand or Promote");
937
938 if (LA == TypeSplitVector)
939 return LegalizeKind(LA, EVT(SVT).getHalfNumVectorElementsVT(Context));
940 if (LA == TypeScalarizeVector)
941 return LegalizeKind(LA, SVT.getVectorElementType());
942 return LegalizeKind(LA, NVT);
943 }
944
945 // Handle Extended Scalar Types.
946 if (!VT.isVector()) {
947 assert(VT.isInteger() && "Float types must be simple");
948 unsigned BitSize = VT.getSizeInBits();
949 // First promote to a power-of-two size, then expand if necessary.
950 if (BitSize < 8 || !isPowerOf2_32(BitSize)) {
951 EVT NVT = VT.getRoundIntegerType(Context);
952 assert(NVT != VT && "Unable to round integer VT");
953 LegalizeKind NextStep = getTypeConversion(Context, NVT);
954 // Avoid multi-step promotion.
955 if (NextStep.first == TypePromoteInteger)
956 return NextStep;
957 // Return rounded integer type.
958 return LegalizeKind(TypePromoteInteger, NVT);
959 }
960
961 return LegalizeKind(TypeExpandInteger,
962 EVT::getIntegerVT(Context, VT.getSizeInBits() / 2));
963 }
964
965 // Handle vector types.
966 ElementCount NumElts = VT.getVectorElementCount();
967 EVT EltVT = VT.getVectorElementType();
968
969 // Vectors with only one element are always scalarized.
970 if (NumElts.isScalar())
971 return LegalizeKind(TypeScalarizeVector, EltVT);
972
973 // Try to widen vector elements until the element type is a power of two and
974 // promote it to a legal type later on, for example:
975 // <3 x i8> -> <4 x i8> -> <4 x i32>
976 if (EltVT.isInteger()) {
977 // Vectors with a number of elements that is not a power of two are always
978 // widened, for example <3 x i8> -> <4 x i8>.
979 if (!VT.isPow2VectorType()) {
980 NumElts = NumElts.coefficientNextPowerOf2();
981 EVT NVT = EVT::getVectorVT(Context, EltVT, NumElts);
982 return LegalizeKind(TypeWidenVector, NVT);
983 }
984
985 // Examine the element type.
986 LegalizeKind LK = getTypeConversion(Context, EltVT);
987
988 // If type is to be expanded, split the vector.
989 // <4 x i140> -> <2 x i140>
990 if (LK.first == TypeExpandInteger) {
991 if (VT.getVectorElementCount().isScalable())
992 return LegalizeKind(TypeScalarizeScalableVector, EltVT);
993 return LegalizeKind(TypeSplitVector,
994 VT.getHalfNumVectorElementsVT(Context));
995 }
996
997 // Promote the integer element types until a legal vector type is found
998 // or until the element integer type is too big. If a legal type was not
999 // found, fallback to the usual mechanism of widening/splitting the
1000 // vector.
1001 EVT OldEltVT = EltVT;
1002 while (true) {
1003 // Increase the bitwidth of the element to the next pow-of-two
1004 // (which is greater than 8 bits).
1005 EltVT = EVT::getIntegerVT(Context, 1 + EltVT.getSizeInBits())
1006 .getRoundIntegerType(Context);
1007
1008 // Stop trying when getting a non-simple element type.
1009 // Note that vector elements may be greater than legal vector element
1010 // types. Example: X86 XMM registers hold 64bit element on 32bit
1011 // systems.
1012 if (!EltVT.isSimple())
1013 break;
1014
1015 // Build a new vector type and check if it is legal.
1016 MVT NVT = MVT::getVectorVT(EltVT.getSimpleVT(), NumElts);
1017 // Found a legal promoted vector type.
1018 if (NVT != MVT() && ValueTypeActions.getTypeAction(NVT) == TypeLegal)
1019 return LegalizeKind(TypePromoteInteger,
1020 EVT::getVectorVT(Context, EltVT, NumElts));
1021 }
1022
1023 // Reset the type to the unexpanded type if we did not find a legal vector
1024 // type with a promoted vector element type.
1025 EltVT = OldEltVT;
1026 }
1027
1028 // Try to widen the vector until a legal type is found.
1029 // If there is no wider legal type, split the vector.
1030 while (true) {
1031 // Round up to the next power of 2.
1032 NumElts = NumElts.coefficientNextPowerOf2();
1033
1034 // If there is no simple vector type with this many elements then there
1035 // cannot be a larger legal vector type. Note that this assumes that
1036 // there are no skipped intermediate vector types in the simple types.
1037 if (!EltVT.isSimple())
1038 break;
1039 MVT LargerVector = MVT::getVectorVT(EltVT.getSimpleVT(), NumElts);
1040 if (LargerVector == MVT())
1041 break;
1042
1043 // If this type is legal then widen the vector.
1044 if (ValueTypeActions.getTypeAction(LargerVector) == TypeLegal)
1045 return LegalizeKind(TypeWidenVector, LargerVector);
1046 }
1047
1048 // Widen odd vectors to next power of two.
1049 if (!VT.isPow2VectorType()) {
1050 EVT NVT = VT.getPow2VectorType(Context);
1051 return LegalizeKind(TypeWidenVector, NVT);
1052 }
1053
1054 if (VT.getVectorElementCount() == ElementCount::getScalable(1))
1055 return LegalizeKind(TypeScalarizeScalableVector, EltVT);
1056
1057 // Vectors with illegal element types are expanded.
1058 EVT NVT = EVT::getVectorVT(Context, EltVT,
1059 VT.getVectorElementCount().divideCoefficientBy(2));
1060 return LegalizeKind(TypeSplitVector, NVT);
1061 }
1062
getVectorTypeBreakdownMVT(MVT VT,MVT & IntermediateVT,unsigned & NumIntermediates,MVT & RegisterVT,TargetLoweringBase * TLI)1063 static unsigned getVectorTypeBreakdownMVT(MVT VT, MVT &IntermediateVT,
1064 unsigned &NumIntermediates,
1065 MVT &RegisterVT,
1066 TargetLoweringBase *TLI) {
1067 // Figure out the right, legal destination reg to copy into.
1068 ElementCount EC = VT.getVectorElementCount();
1069 MVT EltTy = VT.getVectorElementType();
1070
1071 unsigned NumVectorRegs = 1;
1072
1073 // Scalable vectors cannot be scalarized, so splitting or widening is
1074 // required.
1075 if (VT.isScalableVector() && !isPowerOf2_32(EC.getKnownMinValue()))
1076 llvm_unreachable(
1077 "Splitting or widening of non-power-of-2 MVTs is not implemented.");
1078
1079 // FIXME: We don't support non-power-of-2-sized vectors for now.
1080 // Ideally we could break down into LHS/RHS like LegalizeDAG does.
1081 if (!isPowerOf2_32(EC.getKnownMinValue())) {
1082 // Split EC to unit size (scalable property is preserved).
1083 NumVectorRegs = EC.getKnownMinValue();
1084 EC = ElementCount::getFixed(1);
1085 }
1086
1087 // Divide the input until we get to a supported size. This will
1088 // always end up with an EC that represent a scalar or a scalable
1089 // scalar.
1090 while (EC.getKnownMinValue() > 1 &&
1091 !TLI->isTypeLegal(MVT::getVectorVT(EltTy, EC))) {
1092 EC = EC.divideCoefficientBy(2);
1093 NumVectorRegs <<= 1;
1094 }
1095
1096 NumIntermediates = NumVectorRegs;
1097
1098 MVT NewVT = MVT::getVectorVT(EltTy, EC);
1099 if (!TLI->isTypeLegal(NewVT))
1100 NewVT = EltTy;
1101 IntermediateVT = NewVT;
1102
1103 unsigned LaneSizeInBits = NewVT.getScalarSizeInBits();
1104
1105 // Convert sizes such as i33 to i64.
1106 LaneSizeInBits = llvm::bit_ceil(LaneSizeInBits);
1107
1108 MVT DestVT = TLI->getRegisterType(NewVT);
1109 RegisterVT = DestVT;
1110 if (EVT(DestVT).bitsLT(NewVT)) // Value is expanded, e.g. i64 -> i16.
1111 return NumVectorRegs * (LaneSizeInBits / DestVT.getScalarSizeInBits());
1112
1113 // Otherwise, promotion or legal types use the same number of registers as
1114 // the vector decimated to the appropriate level.
1115 return NumVectorRegs;
1116 }
1117
1118 /// isLegalRC - Return true if the value types that can be represented by the
1119 /// specified register class are all legal.
isLegalRC(const TargetRegisterInfo & TRI,const TargetRegisterClass & RC) const1120 bool TargetLoweringBase::isLegalRC(const TargetRegisterInfo &TRI,
1121 const TargetRegisterClass &RC) const {
1122 for (const auto *I = TRI.legalclasstypes_begin(RC); *I != MVT::Other; ++I)
1123 if (isTypeLegal(*I))
1124 return true;
1125 return false;
1126 }
1127
1128 /// Replace/modify any TargetFrameIndex operands with a targte-dependent
1129 /// sequence of memory operands that is recognized by PrologEpilogInserter.
1130 MachineBasicBlock *
emitPatchPoint(MachineInstr & InitialMI,MachineBasicBlock * MBB) const1131 TargetLoweringBase::emitPatchPoint(MachineInstr &InitialMI,
1132 MachineBasicBlock *MBB) const {
1133 MachineInstr *MI = &InitialMI;
1134 MachineFunction &MF = *MI->getMF();
1135 MachineFrameInfo &MFI = MF.getFrameInfo();
1136
1137 // We're handling multiple types of operands here:
1138 // PATCHPOINT MetaArgs - live-in, read only, direct
1139 // STATEPOINT Deopt Spill - live-through, read only, indirect
1140 // STATEPOINT Deopt Alloca - live-through, read only, direct
1141 // (We're currently conservative and mark the deopt slots read/write in
1142 // practice.)
1143 // STATEPOINT GC Spill - live-through, read/write, indirect
1144 // STATEPOINT GC Alloca - live-through, read/write, direct
1145 // The live-in vs live-through is handled already (the live through ones are
1146 // all stack slots), but we need to handle the different type of stackmap
1147 // operands and memory effects here.
1148
1149 if (llvm::none_of(MI->operands(),
1150 [](MachineOperand &Operand) { return Operand.isFI(); }))
1151 return MBB;
1152
1153 MachineInstrBuilder MIB = BuildMI(MF, MI->getDebugLoc(), MI->getDesc());
1154
1155 // Inherit previous memory operands.
1156 MIB.cloneMemRefs(*MI);
1157
1158 for (unsigned i = 0; i < MI->getNumOperands(); ++i) {
1159 MachineOperand &MO = MI->getOperand(i);
1160 if (!MO.isFI()) {
1161 // Index of Def operand this Use it tied to.
1162 // Since Defs are coming before Uses, if Use is tied, then
1163 // index of Def must be smaller that index of that Use.
1164 // Also, Defs preserve their position in new MI.
1165 unsigned TiedTo = i;
1166 if (MO.isReg() && MO.isTied())
1167 TiedTo = MI->findTiedOperandIdx(i);
1168 MIB.add(MO);
1169 if (TiedTo < i)
1170 MIB->tieOperands(TiedTo, MIB->getNumOperands() - 1);
1171 continue;
1172 }
1173
1174 // foldMemoryOperand builds a new MI after replacing a single FI operand
1175 // with the canonical set of five x86 addressing-mode operands.
1176 int FI = MO.getIndex();
1177
1178 // Add frame index operands recognized by stackmaps.cpp
1179 if (MFI.isStatepointSpillSlotObjectIndex(FI)) {
1180 // indirect-mem-ref tag, size, #FI, offset.
1181 // Used for spills inserted by StatepointLowering. This codepath is not
1182 // used for patchpoints/stackmaps at all, for these spilling is done via
1183 // foldMemoryOperand callback only.
1184 assert(MI->getOpcode() == TargetOpcode::STATEPOINT && "sanity");
1185 MIB.addImm(StackMaps::IndirectMemRefOp);
1186 MIB.addImm(MFI.getObjectSize(FI));
1187 MIB.add(MO);
1188 MIB.addImm(0);
1189 } else {
1190 // direct-mem-ref tag, #FI, offset.
1191 // Used by patchpoint, and direct alloca arguments to statepoints
1192 MIB.addImm(StackMaps::DirectMemRefOp);
1193 MIB.add(MO);
1194 MIB.addImm(0);
1195 }
1196
1197 assert(MIB->mayLoad() && "Folded a stackmap use to a non-load!");
1198
1199 // Add a new memory operand for this FI.
1200 assert(MFI.getObjectOffset(FI) != -1);
1201
1202 // Note: STATEPOINT MMOs are added during SelectionDAG. STACKMAP, and
1203 // PATCHPOINT should be updated to do the same. (TODO)
1204 if (MI->getOpcode() != TargetOpcode::STATEPOINT) {
1205 auto Flags = MachineMemOperand::MOLoad;
1206 MachineMemOperand *MMO = MF.getMachineMemOperand(
1207 MachinePointerInfo::getFixedStack(MF, FI), Flags,
1208 MF.getDataLayout().getPointerSize(), MFI.getObjectAlign(FI));
1209 MIB->addMemOperand(MF, MMO);
1210 }
1211 }
1212 MBB->insert(MachineBasicBlock::iterator(MI), MIB);
1213 MI->eraseFromParent();
1214 return MBB;
1215 }
1216
1217 /// findRepresentativeClass - Return the largest legal super-reg register class
1218 /// of the register class for the specified type and its associated "cost".
1219 // This function is in TargetLowering because it uses RegClassForVT which would
1220 // need to be moved to TargetRegisterInfo and would necessitate moving
1221 // isTypeLegal over as well - a massive change that would just require
1222 // TargetLowering having a TargetRegisterInfo class member that it would use.
1223 std::pair<const TargetRegisterClass *, uint8_t>
findRepresentativeClass(const TargetRegisterInfo * TRI,MVT VT) const1224 TargetLoweringBase::findRepresentativeClass(const TargetRegisterInfo *TRI,
1225 MVT VT) const {
1226 const TargetRegisterClass *RC = RegClassForVT[VT.SimpleTy];
1227 if (!RC)
1228 return std::make_pair(RC, 0);
1229
1230 // Compute the set of all super-register classes.
1231 BitVector SuperRegRC(TRI->getNumRegClasses());
1232 for (SuperRegClassIterator RCI(RC, TRI); RCI.isValid(); ++RCI)
1233 SuperRegRC.setBitsInMask(RCI.getMask());
1234
1235 // Find the first legal register class with the largest spill size.
1236 const TargetRegisterClass *BestRC = RC;
1237 for (unsigned i : SuperRegRC.set_bits()) {
1238 const TargetRegisterClass *SuperRC = TRI->getRegClass(i);
1239 // We want the largest possible spill size.
1240 if (TRI->getSpillSize(*SuperRC) <= TRI->getSpillSize(*BestRC))
1241 continue;
1242 if (!isLegalRC(*TRI, *SuperRC))
1243 continue;
1244 BestRC = SuperRC;
1245 }
1246 return std::make_pair(BestRC, 1);
1247 }
1248
1249 /// computeRegisterProperties - Once all of the register classes are added,
1250 /// this allows us to compute derived properties we expose.
computeRegisterProperties(const TargetRegisterInfo * TRI)1251 void TargetLoweringBase::computeRegisterProperties(
1252 const TargetRegisterInfo *TRI) {
1253 // Everything defaults to needing one register.
1254 for (unsigned i = 0; i != MVT::VALUETYPE_SIZE; ++i) {
1255 NumRegistersForVT[i] = 1;
1256 RegisterTypeForVT[i] = TransformToType[i] = (MVT::SimpleValueType)i;
1257 }
1258 // ...except isVoid, which doesn't need any registers.
1259 NumRegistersForVT[MVT::isVoid] = 0;
1260
1261 // Find the largest integer register class.
1262 unsigned LargestIntReg = MVT::LAST_INTEGER_VALUETYPE;
1263 for (; RegClassForVT[LargestIntReg] == nullptr; --LargestIntReg)
1264 assert(LargestIntReg != MVT::i1 && "No integer registers defined!");
1265
1266 // Every integer value type larger than this largest register takes twice as
1267 // many registers to represent as the previous ValueType.
1268 for (unsigned ExpandedReg = LargestIntReg + 1;
1269 ExpandedReg <= MVT::LAST_INTEGER_VALUETYPE; ++ExpandedReg) {
1270 NumRegistersForVT[ExpandedReg] = 2*NumRegistersForVT[ExpandedReg-1];
1271 RegisterTypeForVT[ExpandedReg] = (MVT::SimpleValueType)LargestIntReg;
1272 TransformToType[ExpandedReg] = (MVT::SimpleValueType)(ExpandedReg - 1);
1273 ValueTypeActions.setTypeAction((MVT::SimpleValueType)ExpandedReg,
1274 TypeExpandInteger);
1275 }
1276
1277 // Inspect all of the ValueType's smaller than the largest integer
1278 // register to see which ones need promotion.
1279 unsigned LegalIntReg = LargestIntReg;
1280 for (unsigned IntReg = LargestIntReg - 1;
1281 IntReg >= (unsigned)MVT::i1; --IntReg) {
1282 MVT IVT = (MVT::SimpleValueType)IntReg;
1283 if (isTypeLegal(IVT)) {
1284 LegalIntReg = IntReg;
1285 } else {
1286 RegisterTypeForVT[IntReg] = TransformToType[IntReg] =
1287 (MVT::SimpleValueType)LegalIntReg;
1288 ValueTypeActions.setTypeAction(IVT, TypePromoteInteger);
1289 }
1290 }
1291
1292 // ppcf128 type is really two f64's.
1293 if (!isTypeLegal(MVT::ppcf128)) {
1294 if (isTypeLegal(MVT::f64)) {
1295 NumRegistersForVT[MVT::ppcf128] = 2*NumRegistersForVT[MVT::f64];
1296 RegisterTypeForVT[MVT::ppcf128] = MVT::f64;
1297 TransformToType[MVT::ppcf128] = MVT::f64;
1298 ValueTypeActions.setTypeAction(MVT::ppcf128, TypeExpandFloat);
1299 } else {
1300 NumRegistersForVT[MVT::ppcf128] = NumRegistersForVT[MVT::i128];
1301 RegisterTypeForVT[MVT::ppcf128] = RegisterTypeForVT[MVT::i128];
1302 TransformToType[MVT::ppcf128] = MVT::i128;
1303 ValueTypeActions.setTypeAction(MVT::ppcf128, TypeSoftenFloat);
1304 }
1305 }
1306
1307 // Decide how to handle f128. If the target does not have native f128 support,
1308 // expand it to i128 and we will be generating soft float library calls.
1309 if (!isTypeLegal(MVT::f128)) {
1310 NumRegistersForVT[MVT::f128] = NumRegistersForVT[MVT::i128];
1311 RegisterTypeForVT[MVT::f128] = RegisterTypeForVT[MVT::i128];
1312 TransformToType[MVT::f128] = MVT::i128;
1313 ValueTypeActions.setTypeAction(MVT::f128, TypeSoftenFloat);
1314 }
1315
1316 // Decide how to handle f80. If the target does not have native f80 support,
1317 // expand it to i96 and we will be generating soft float library calls.
1318 if (!isTypeLegal(MVT::f80)) {
1319 NumRegistersForVT[MVT::f80] = 3*NumRegistersForVT[MVT::i32];
1320 RegisterTypeForVT[MVT::f80] = RegisterTypeForVT[MVT::i32];
1321 TransformToType[MVT::f80] = MVT::i32;
1322 ValueTypeActions.setTypeAction(MVT::f80, TypeSoftenFloat);
1323 }
1324
1325 // Decide how to handle f64. If the target does not have native f64 support,
1326 // expand it to i64 and we will be generating soft float library calls.
1327 if (!isTypeLegal(MVT::f64)) {
1328 NumRegistersForVT[MVT::f64] = NumRegistersForVT[MVT::i64];
1329 RegisterTypeForVT[MVT::f64] = RegisterTypeForVT[MVT::i64];
1330 TransformToType[MVT::f64] = MVT::i64;
1331 ValueTypeActions.setTypeAction(MVT::f64, TypeSoftenFloat);
1332 }
1333
1334 // Decide how to handle f32. If the target does not have native f32 support,
1335 // expand it to i32 and we will be generating soft float library calls.
1336 if (!isTypeLegal(MVT::f32)) {
1337 NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::i32];
1338 RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::i32];
1339 TransformToType[MVT::f32] = MVT::i32;
1340 ValueTypeActions.setTypeAction(MVT::f32, TypeSoftenFloat);
1341 }
1342
1343 // Decide how to handle f16. If the target does not have native f16 support,
1344 // promote it to f32, because there are no f16 library calls (except for
1345 // conversions).
1346 if (!isTypeLegal(MVT::f16)) {
1347 // Allow targets to control how we legalize half.
1348 bool SoftPromoteHalfType = softPromoteHalfType();
1349 bool UseFPRegsForHalfType = !SoftPromoteHalfType || useFPRegsForHalfType();
1350
1351 if (!UseFPRegsForHalfType) {
1352 NumRegistersForVT[MVT::f16] = NumRegistersForVT[MVT::i16];
1353 RegisterTypeForVT[MVT::f16] = RegisterTypeForVT[MVT::i16];
1354 } else {
1355 NumRegistersForVT[MVT::f16] = NumRegistersForVT[MVT::f32];
1356 RegisterTypeForVT[MVT::f16] = RegisterTypeForVT[MVT::f32];
1357 }
1358 TransformToType[MVT::f16] = MVT::f32;
1359 if (SoftPromoteHalfType) {
1360 ValueTypeActions.setTypeAction(MVT::f16, TypeSoftPromoteHalf);
1361 } else {
1362 ValueTypeActions.setTypeAction(MVT::f16, TypePromoteFloat);
1363 }
1364 }
1365
1366 // Decide how to handle bf16. If the target does not have native bf16 support,
1367 // promote it to f32, because there are no bf16 library calls (except for
1368 // converting from f32 to bf16).
1369 if (!isTypeLegal(MVT::bf16)) {
1370 NumRegistersForVT[MVT::bf16] = NumRegistersForVT[MVT::f32];
1371 RegisterTypeForVT[MVT::bf16] = RegisterTypeForVT[MVT::f32];
1372 TransformToType[MVT::bf16] = MVT::f32;
1373 ValueTypeActions.setTypeAction(MVT::bf16, TypeSoftPromoteHalf);
1374 }
1375
1376 // Loop over all of the vector value types to see which need transformations.
1377 for (unsigned i = MVT::FIRST_VECTOR_VALUETYPE;
1378 i <= (unsigned)MVT::LAST_VECTOR_VALUETYPE; ++i) {
1379 MVT VT = (MVT::SimpleValueType) i;
1380 if (isTypeLegal(VT))
1381 continue;
1382
1383 MVT EltVT = VT.getVectorElementType();
1384 ElementCount EC = VT.getVectorElementCount();
1385 bool IsLegalWiderType = false;
1386 bool IsScalable = VT.isScalableVector();
1387 LegalizeTypeAction PreferredAction = getPreferredVectorAction(VT);
1388 switch (PreferredAction) {
1389 case TypePromoteInteger: {
1390 MVT::SimpleValueType EndVT = IsScalable ?
1391 MVT::LAST_INTEGER_SCALABLE_VECTOR_VALUETYPE :
1392 MVT::LAST_INTEGER_FIXEDLEN_VECTOR_VALUETYPE;
1393 // Try to promote the elements of integer vectors. If no legal
1394 // promotion was found, fall through to the widen-vector method.
1395 for (unsigned nVT = i + 1;
1396 (MVT::SimpleValueType)nVT <= EndVT; ++nVT) {
1397 MVT SVT = (MVT::SimpleValueType) nVT;
1398 // Promote vectors of integers to vectors with the same number
1399 // of elements, with a wider element type.
1400 if (SVT.getScalarSizeInBits() > EltVT.getFixedSizeInBits() &&
1401 SVT.getVectorElementCount() == EC && isTypeLegal(SVT)) {
1402 TransformToType[i] = SVT;
1403 RegisterTypeForVT[i] = SVT;
1404 NumRegistersForVT[i] = 1;
1405 ValueTypeActions.setTypeAction(VT, TypePromoteInteger);
1406 IsLegalWiderType = true;
1407 break;
1408 }
1409 }
1410 if (IsLegalWiderType)
1411 break;
1412 [[fallthrough]];
1413 }
1414
1415 case TypeWidenVector:
1416 if (isPowerOf2_32(EC.getKnownMinValue())) {
1417 // Try to widen the vector.
1418 for (unsigned nVT = i + 1; nVT <= MVT::LAST_VECTOR_VALUETYPE; ++nVT) {
1419 MVT SVT = (MVT::SimpleValueType) nVT;
1420 if (SVT.getVectorElementType() == EltVT &&
1421 SVT.isScalableVector() == IsScalable &&
1422 SVT.getVectorElementCount().getKnownMinValue() >
1423 EC.getKnownMinValue() &&
1424 isTypeLegal(SVT)) {
1425 TransformToType[i] = SVT;
1426 RegisterTypeForVT[i] = SVT;
1427 NumRegistersForVT[i] = 1;
1428 ValueTypeActions.setTypeAction(VT, TypeWidenVector);
1429 IsLegalWiderType = true;
1430 break;
1431 }
1432 }
1433 if (IsLegalWiderType)
1434 break;
1435 } else {
1436 // Only widen to the next power of 2 to keep consistency with EVT.
1437 MVT NVT = VT.getPow2VectorType();
1438 if (isTypeLegal(NVT)) {
1439 TransformToType[i] = NVT;
1440 ValueTypeActions.setTypeAction(VT, TypeWidenVector);
1441 RegisterTypeForVT[i] = NVT;
1442 NumRegistersForVT[i] = 1;
1443 break;
1444 }
1445 }
1446 [[fallthrough]];
1447
1448 case TypeSplitVector:
1449 case TypeScalarizeVector: {
1450 MVT IntermediateVT;
1451 MVT RegisterVT;
1452 unsigned NumIntermediates;
1453 unsigned NumRegisters = getVectorTypeBreakdownMVT(VT, IntermediateVT,
1454 NumIntermediates, RegisterVT, this);
1455 NumRegistersForVT[i] = NumRegisters;
1456 assert(NumRegistersForVT[i] == NumRegisters &&
1457 "NumRegistersForVT size cannot represent NumRegisters!");
1458 RegisterTypeForVT[i] = RegisterVT;
1459
1460 MVT NVT = VT.getPow2VectorType();
1461 if (NVT == VT) {
1462 // Type is already a power of 2. The default action is to split.
1463 TransformToType[i] = MVT::Other;
1464 if (PreferredAction == TypeScalarizeVector)
1465 ValueTypeActions.setTypeAction(VT, TypeScalarizeVector);
1466 else if (PreferredAction == TypeSplitVector)
1467 ValueTypeActions.setTypeAction(VT, TypeSplitVector);
1468 else if (EC.getKnownMinValue() > 1)
1469 ValueTypeActions.setTypeAction(VT, TypeSplitVector);
1470 else
1471 ValueTypeActions.setTypeAction(VT, EC.isScalable()
1472 ? TypeScalarizeScalableVector
1473 : TypeScalarizeVector);
1474 } else {
1475 TransformToType[i] = NVT;
1476 ValueTypeActions.setTypeAction(VT, TypeWidenVector);
1477 }
1478 break;
1479 }
1480 default:
1481 llvm_unreachable("Unknown vector legalization action!");
1482 }
1483 }
1484
1485 // Determine the 'representative' register class for each value type.
1486 // An representative register class is the largest (meaning one which is
1487 // not a sub-register class / subreg register class) legal register class for
1488 // a group of value types. For example, on i386, i8, i16, and i32
1489 // representative would be GR32; while on x86_64 it's GR64.
1490 for (unsigned i = 0; i != MVT::VALUETYPE_SIZE; ++i) {
1491 const TargetRegisterClass* RRC;
1492 uint8_t Cost;
1493 std::tie(RRC, Cost) = findRepresentativeClass(TRI, (MVT::SimpleValueType)i);
1494 RepRegClassForVT[i] = RRC;
1495 RepRegClassCostForVT[i] = Cost;
1496 }
1497 }
1498
getSetCCResultType(const DataLayout & DL,LLVMContext &,EVT VT) const1499 EVT TargetLoweringBase::getSetCCResultType(const DataLayout &DL, LLVMContext &,
1500 EVT VT) const {
1501 assert(!VT.isVector() && "No default SetCC type for vectors!");
1502 return getPointerTy(DL).SimpleTy;
1503 }
1504
getCmpLibcallReturnType() const1505 MVT::SimpleValueType TargetLoweringBase::getCmpLibcallReturnType() const {
1506 return MVT::i32; // return the default value
1507 }
1508
1509 /// getVectorTypeBreakdown - Vector types are broken down into some number of
1510 /// legal first class types. For example, MVT::v8f32 maps to 2 MVT::v4f32
1511 /// with Altivec or SSE1, or 8 promoted MVT::f64 values with the X86 FP stack.
1512 /// Similarly, MVT::v2i64 turns into 4 MVT::i32 values with both PPC and X86.
1513 ///
1514 /// This method returns the number of registers needed, and the VT for each
1515 /// register. It also returns the VT and quantity of the intermediate values
1516 /// before they are promoted/expanded.
getVectorTypeBreakdown(LLVMContext & Context,EVT VT,EVT & IntermediateVT,unsigned & NumIntermediates,MVT & RegisterVT) const1517 unsigned TargetLoweringBase::getVectorTypeBreakdown(LLVMContext &Context,
1518 EVT VT, EVT &IntermediateVT,
1519 unsigned &NumIntermediates,
1520 MVT &RegisterVT) const {
1521 ElementCount EltCnt = VT.getVectorElementCount();
1522
1523 // If there is a wider vector type with the same element type as this one,
1524 // or a promoted vector type that has the same number of elements which
1525 // are wider, then we should convert to that legal vector type.
1526 // This handles things like <2 x float> -> <4 x float> and
1527 // <4 x i1> -> <4 x i32>.
1528 LegalizeTypeAction TA = getTypeAction(Context, VT);
1529 if (!EltCnt.isScalar() &&
1530 (TA == TypeWidenVector || TA == TypePromoteInteger)) {
1531 EVT RegisterEVT = getTypeToTransformTo(Context, VT);
1532 if (isTypeLegal(RegisterEVT)) {
1533 IntermediateVT = RegisterEVT;
1534 RegisterVT = RegisterEVT.getSimpleVT();
1535 NumIntermediates = 1;
1536 return 1;
1537 }
1538 }
1539
1540 // Figure out the right, legal destination reg to copy into.
1541 EVT EltTy = VT.getVectorElementType();
1542
1543 unsigned NumVectorRegs = 1;
1544
1545 // Scalable vectors cannot be scalarized, so handle the legalisation of the
1546 // types like done elsewhere in SelectionDAG.
1547 if (EltCnt.isScalable()) {
1548 LegalizeKind LK;
1549 EVT PartVT = VT;
1550 do {
1551 // Iterate until we've found a legal (part) type to hold VT.
1552 LK = getTypeConversion(Context, PartVT);
1553 PartVT = LK.second;
1554 } while (LK.first != TypeLegal);
1555
1556 if (!PartVT.isVector()) {
1557 report_fatal_error(
1558 "Don't know how to legalize this scalable vector type");
1559 }
1560
1561 NumIntermediates =
1562 divideCeil(VT.getVectorElementCount().getKnownMinValue(),
1563 PartVT.getVectorElementCount().getKnownMinValue());
1564 IntermediateVT = PartVT;
1565 RegisterVT = getRegisterType(Context, IntermediateVT);
1566 return NumIntermediates;
1567 }
1568
1569 // FIXME: We don't support non-power-of-2-sized vectors for now. Ideally
1570 // we could break down into LHS/RHS like LegalizeDAG does.
1571 if (!isPowerOf2_32(EltCnt.getKnownMinValue())) {
1572 NumVectorRegs = EltCnt.getKnownMinValue();
1573 EltCnt = ElementCount::getFixed(1);
1574 }
1575
1576 // Divide the input until we get to a supported size. This will always
1577 // end with a scalar if the target doesn't support vectors.
1578 while (EltCnt.getKnownMinValue() > 1 &&
1579 !isTypeLegal(EVT::getVectorVT(Context, EltTy, EltCnt))) {
1580 EltCnt = EltCnt.divideCoefficientBy(2);
1581 NumVectorRegs <<= 1;
1582 }
1583
1584 NumIntermediates = NumVectorRegs;
1585
1586 EVT NewVT = EVT::getVectorVT(Context, EltTy, EltCnt);
1587 if (!isTypeLegal(NewVT))
1588 NewVT = EltTy;
1589 IntermediateVT = NewVT;
1590
1591 MVT DestVT = getRegisterType(Context, NewVT);
1592 RegisterVT = DestVT;
1593
1594 if (EVT(DestVT).bitsLT(NewVT)) { // Value is expanded, e.g. i64 -> i16.
1595 TypeSize NewVTSize = NewVT.getSizeInBits();
1596 // Convert sizes such as i33 to i64.
1597 if (!llvm::has_single_bit<uint32_t>(NewVTSize.getKnownMinValue()))
1598 NewVTSize = NewVTSize.coefficientNextPowerOf2();
1599 return NumVectorRegs*(NewVTSize/DestVT.getSizeInBits());
1600 }
1601
1602 // Otherwise, promotion or legal types use the same number of registers as
1603 // the vector decimated to the appropriate level.
1604 return NumVectorRegs;
1605 }
1606
isSuitableForJumpTable(const SwitchInst * SI,uint64_t NumCases,uint64_t Range,ProfileSummaryInfo * PSI,BlockFrequencyInfo * BFI) const1607 bool TargetLoweringBase::isSuitableForJumpTable(const SwitchInst *SI,
1608 uint64_t NumCases,
1609 uint64_t Range,
1610 ProfileSummaryInfo *PSI,
1611 BlockFrequencyInfo *BFI) const {
1612 // FIXME: This function check the maximum table size and density, but the
1613 // minimum size is not checked. It would be nice if the minimum size is
1614 // also combined within this function. Currently, the minimum size check is
1615 // performed in findJumpTable() in SelectionDAGBuiler and
1616 // getEstimatedNumberOfCaseClusters() in BasicTTIImpl.
1617 const bool OptForSize =
1618 SI->getParent()->getParent()->hasOptSize() ||
1619 llvm::shouldOptimizeForSize(SI->getParent(), PSI, BFI);
1620 const unsigned MinDensity = getMinimumJumpTableDensity(OptForSize);
1621 const unsigned MaxJumpTableSize = getMaximumJumpTableSize();
1622
1623 // Check whether the number of cases is small enough and
1624 // the range is dense enough for a jump table.
1625 return (OptForSize || Range <= MaxJumpTableSize) &&
1626 (NumCases * 100 >= Range * MinDensity);
1627 }
1628
getPreferredSwitchConditionType(LLVMContext & Context,EVT ConditionVT) const1629 MVT TargetLoweringBase::getPreferredSwitchConditionType(LLVMContext &Context,
1630 EVT ConditionVT) const {
1631 return getRegisterType(Context, ConditionVT);
1632 }
1633
1634 /// Get the EVTs and ArgFlags collections that represent the legalized return
1635 /// type of the given function. This does not require a DAG or a return value,
1636 /// and is suitable for use before any DAGs for the function are constructed.
1637 /// TODO: Move this out of TargetLowering.cpp.
GetReturnInfo(CallingConv::ID CC,Type * ReturnType,AttributeList attr,SmallVectorImpl<ISD::OutputArg> & Outs,const TargetLowering & TLI,const DataLayout & DL)1638 void llvm::GetReturnInfo(CallingConv::ID CC, Type *ReturnType,
1639 AttributeList attr,
1640 SmallVectorImpl<ISD::OutputArg> &Outs,
1641 const TargetLowering &TLI, const DataLayout &DL) {
1642 SmallVector<EVT, 4> ValueVTs;
1643 ComputeValueVTs(TLI, DL, ReturnType, ValueVTs);
1644 unsigned NumValues = ValueVTs.size();
1645 if (NumValues == 0) return;
1646
1647 for (unsigned j = 0, f = NumValues; j != f; ++j) {
1648 EVT VT = ValueVTs[j];
1649 ISD::NodeType ExtendKind = ISD::ANY_EXTEND;
1650
1651 if (attr.hasRetAttr(Attribute::SExt))
1652 ExtendKind = ISD::SIGN_EXTEND;
1653 else if (attr.hasRetAttr(Attribute::ZExt))
1654 ExtendKind = ISD::ZERO_EXTEND;
1655
1656 if (ExtendKind != ISD::ANY_EXTEND && VT.isInteger())
1657 VT = TLI.getTypeForExtReturn(ReturnType->getContext(), VT, ExtendKind);
1658
1659 unsigned NumParts =
1660 TLI.getNumRegistersForCallingConv(ReturnType->getContext(), CC, VT);
1661 MVT PartVT =
1662 TLI.getRegisterTypeForCallingConv(ReturnType->getContext(), CC, VT);
1663
1664 // 'inreg' on function refers to return value
1665 ISD::ArgFlagsTy Flags = ISD::ArgFlagsTy();
1666 if (attr.hasRetAttr(Attribute::InReg))
1667 Flags.setInReg();
1668
1669 // Propagate extension type if any
1670 if (attr.hasRetAttr(Attribute::SExt))
1671 Flags.setSExt();
1672 else if (attr.hasRetAttr(Attribute::ZExt))
1673 Flags.setZExt();
1674
1675 for (unsigned i = 0; i < NumParts; ++i) {
1676 ISD::ArgFlagsTy OutFlags = Flags;
1677 if (NumParts > 1 && i == 0)
1678 OutFlags.setSplit();
1679 else if (i == NumParts - 1 && i != 0)
1680 OutFlags.setSplitEnd();
1681
1682 Outs.push_back(
1683 ISD::OutputArg(OutFlags, PartVT, VT, /*isfixed=*/true, 0, 0));
1684 }
1685 }
1686 }
1687
1688 /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
1689 /// function arguments in the caller parameter area. This is the actual
1690 /// alignment, not its logarithm.
getByValTypeAlignment(Type * Ty,const DataLayout & DL) const1691 uint64_t TargetLoweringBase::getByValTypeAlignment(Type *Ty,
1692 const DataLayout &DL) const {
1693 return DL.getABITypeAlign(Ty).value();
1694 }
1695
allowsMemoryAccessForAlignment(LLVMContext & Context,const DataLayout & DL,EVT VT,unsigned AddrSpace,Align Alignment,MachineMemOperand::Flags Flags,unsigned * Fast) const1696 bool TargetLoweringBase::allowsMemoryAccessForAlignment(
1697 LLVMContext &Context, const DataLayout &DL, EVT VT, unsigned AddrSpace,
1698 Align Alignment, MachineMemOperand::Flags Flags, unsigned *Fast) const {
1699 // Check if the specified alignment is sufficient based on the data layout.
1700 // TODO: While using the data layout works in practice, a better solution
1701 // would be to implement this check directly (make this a virtual function).
1702 // For example, the ABI alignment may change based on software platform while
1703 // this function should only be affected by hardware implementation.
1704 Type *Ty = VT.getTypeForEVT(Context);
1705 if (VT.isZeroSized() || Alignment >= DL.getABITypeAlign(Ty)) {
1706 // Assume that an access that meets the ABI-specified alignment is fast.
1707 if (Fast != nullptr)
1708 *Fast = 1;
1709 return true;
1710 }
1711
1712 // This is a misaligned access.
1713 return allowsMisalignedMemoryAccesses(VT, AddrSpace, Alignment, Flags, Fast);
1714 }
1715
allowsMemoryAccessForAlignment(LLVMContext & Context,const DataLayout & DL,EVT VT,const MachineMemOperand & MMO,unsigned * Fast) const1716 bool TargetLoweringBase::allowsMemoryAccessForAlignment(
1717 LLVMContext &Context, const DataLayout &DL, EVT VT,
1718 const MachineMemOperand &MMO, unsigned *Fast) const {
1719 return allowsMemoryAccessForAlignment(Context, DL, VT, MMO.getAddrSpace(),
1720 MMO.getAlign(), MMO.getFlags(), Fast);
1721 }
1722
allowsMemoryAccess(LLVMContext & Context,const DataLayout & DL,EVT VT,unsigned AddrSpace,Align Alignment,MachineMemOperand::Flags Flags,unsigned * Fast) const1723 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
1724 const DataLayout &DL, EVT VT,
1725 unsigned AddrSpace, Align Alignment,
1726 MachineMemOperand::Flags Flags,
1727 unsigned *Fast) const {
1728 return allowsMemoryAccessForAlignment(Context, DL, VT, AddrSpace, Alignment,
1729 Flags, Fast);
1730 }
1731
allowsMemoryAccess(LLVMContext & Context,const DataLayout & DL,EVT VT,const MachineMemOperand & MMO,unsigned * Fast) const1732 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
1733 const DataLayout &DL, EVT VT,
1734 const MachineMemOperand &MMO,
1735 unsigned *Fast) const {
1736 return allowsMemoryAccess(Context, DL, VT, MMO.getAddrSpace(), MMO.getAlign(),
1737 MMO.getFlags(), Fast);
1738 }
1739
allowsMemoryAccess(LLVMContext & Context,const DataLayout & DL,LLT Ty,const MachineMemOperand & MMO,unsigned * Fast) const1740 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
1741 const DataLayout &DL, LLT Ty,
1742 const MachineMemOperand &MMO,
1743 unsigned *Fast) const {
1744 EVT VT = getApproximateEVTForLLT(Ty, DL, Context);
1745 return allowsMemoryAccess(Context, DL, VT, MMO.getAddrSpace(), MMO.getAlign(),
1746 MMO.getFlags(), Fast);
1747 }
1748
1749 //===----------------------------------------------------------------------===//
1750 // TargetTransformInfo Helpers
1751 //===----------------------------------------------------------------------===//
1752
InstructionOpcodeToISD(unsigned Opcode) const1753 int TargetLoweringBase::InstructionOpcodeToISD(unsigned Opcode) const {
1754 enum InstructionOpcodes {
1755 #define HANDLE_INST(NUM, OPCODE, CLASS) OPCODE = NUM,
1756 #define LAST_OTHER_INST(NUM) InstructionOpcodesCount = NUM
1757 #include "llvm/IR/Instruction.def"
1758 };
1759 switch (static_cast<InstructionOpcodes>(Opcode)) {
1760 case Ret: return 0;
1761 case Br: return 0;
1762 case Switch: return 0;
1763 case IndirectBr: return 0;
1764 case Invoke: return 0;
1765 case CallBr: return 0;
1766 case Resume: return 0;
1767 case Unreachable: return 0;
1768 case CleanupRet: return 0;
1769 case CatchRet: return 0;
1770 case CatchPad: return 0;
1771 case CatchSwitch: return 0;
1772 case CleanupPad: return 0;
1773 case FNeg: return ISD::FNEG;
1774 case Add: return ISD::ADD;
1775 case FAdd: return ISD::FADD;
1776 case Sub: return ISD::SUB;
1777 case FSub: return ISD::FSUB;
1778 case Mul: return ISD::MUL;
1779 case FMul: return ISD::FMUL;
1780 case UDiv: return ISD::UDIV;
1781 case SDiv: return ISD::SDIV;
1782 case FDiv: return ISD::FDIV;
1783 case URem: return ISD::UREM;
1784 case SRem: return ISD::SREM;
1785 case FRem: return ISD::FREM;
1786 case Shl: return ISD::SHL;
1787 case LShr: return ISD::SRL;
1788 case AShr: return ISD::SRA;
1789 case And: return ISD::AND;
1790 case Or: return ISD::OR;
1791 case Xor: return ISD::XOR;
1792 case Alloca: return 0;
1793 case Load: return ISD::LOAD;
1794 case Store: return ISD::STORE;
1795 case GetElementPtr: return 0;
1796 case Fence: return 0;
1797 case AtomicCmpXchg: return 0;
1798 case AtomicRMW: return 0;
1799 case Trunc: return ISD::TRUNCATE;
1800 case ZExt: return ISD::ZERO_EXTEND;
1801 case SExt: return ISD::SIGN_EXTEND;
1802 case FPToUI: return ISD::FP_TO_UINT;
1803 case FPToSI: return ISD::FP_TO_SINT;
1804 case UIToFP: return ISD::UINT_TO_FP;
1805 case SIToFP: return ISD::SINT_TO_FP;
1806 case FPTrunc: return ISD::FP_ROUND;
1807 case FPExt: return ISD::FP_EXTEND;
1808 case PtrToInt: return ISD::BITCAST;
1809 case IntToPtr: return ISD::BITCAST;
1810 case BitCast: return ISD::BITCAST;
1811 case AddrSpaceCast: return ISD::ADDRSPACECAST;
1812 case ICmp: return ISD::SETCC;
1813 case FCmp: return ISD::SETCC;
1814 case PHI: return 0;
1815 case Call: return 0;
1816 case Select: return ISD::SELECT;
1817 case UserOp1: return 0;
1818 case UserOp2: return 0;
1819 case VAArg: return 0;
1820 case ExtractElement: return ISD::EXTRACT_VECTOR_ELT;
1821 case InsertElement: return ISD::INSERT_VECTOR_ELT;
1822 case ShuffleVector: return ISD::VECTOR_SHUFFLE;
1823 case ExtractValue: return ISD::MERGE_VALUES;
1824 case InsertValue: return ISD::MERGE_VALUES;
1825 case LandingPad: return 0;
1826 case Freeze: return ISD::FREEZE;
1827 }
1828
1829 llvm_unreachable("Unknown instruction type encountered!");
1830 }
1831
1832 Value *
getDefaultSafeStackPointerLocation(IRBuilderBase & IRB,bool UseTLS) const1833 TargetLoweringBase::getDefaultSafeStackPointerLocation(IRBuilderBase &IRB,
1834 bool UseTLS) const {
1835 // compiler-rt provides a variable with a magic name. Targets that do not
1836 // link with compiler-rt may also provide such a variable.
1837 Module *M = IRB.GetInsertBlock()->getParent()->getParent();
1838 const char *UnsafeStackPtrVar = "__safestack_unsafe_stack_ptr";
1839 auto UnsafeStackPtr =
1840 dyn_cast_or_null<GlobalVariable>(M->getNamedValue(UnsafeStackPtrVar));
1841
1842 Type *StackPtrTy = PointerType::getUnqual(M->getContext());
1843
1844 if (!UnsafeStackPtr) {
1845 auto TLSModel = UseTLS ?
1846 GlobalValue::InitialExecTLSModel :
1847 GlobalValue::NotThreadLocal;
1848 // The global variable is not defined yet, define it ourselves.
1849 // We use the initial-exec TLS model because we do not support the
1850 // variable living anywhere other than in the main executable.
1851 UnsafeStackPtr = new GlobalVariable(
1852 *M, StackPtrTy, false, GlobalValue::ExternalLinkage, nullptr,
1853 UnsafeStackPtrVar, nullptr, TLSModel);
1854 } else {
1855 // The variable exists, check its type and attributes.
1856 if (UnsafeStackPtr->getValueType() != StackPtrTy)
1857 report_fatal_error(Twine(UnsafeStackPtrVar) + " must have void* type");
1858 if (UseTLS != UnsafeStackPtr->isThreadLocal())
1859 report_fatal_error(Twine(UnsafeStackPtrVar) + " must " +
1860 (UseTLS ? "" : "not ") + "be thread-local");
1861 }
1862 return UnsafeStackPtr;
1863 }
1864
1865 Value *
getSafeStackPointerLocation(IRBuilderBase & IRB) const1866 TargetLoweringBase::getSafeStackPointerLocation(IRBuilderBase &IRB) const {
1867 if (!TM.getTargetTriple().isAndroid())
1868 return getDefaultSafeStackPointerLocation(IRB, true);
1869
1870 // Android provides a libc function to retrieve the address of the current
1871 // thread's unsafe stack pointer.
1872 Module *M = IRB.GetInsertBlock()->getParent()->getParent();
1873 auto *PtrTy = PointerType::getUnqual(M->getContext());
1874 FunctionCallee Fn =
1875 M->getOrInsertFunction("__safestack_pointer_address", PtrTy);
1876 return IRB.CreateCall(Fn);
1877 }
1878
1879 //===----------------------------------------------------------------------===//
1880 // Loop Strength Reduction hooks
1881 //===----------------------------------------------------------------------===//
1882
1883 /// isLegalAddressingMode - Return true if the addressing mode represented
1884 /// by AM is legal for this target, for a load/store of the specified type.
isLegalAddressingMode(const DataLayout & DL,const AddrMode & AM,Type * Ty,unsigned AS,Instruction * I) const1885 bool TargetLoweringBase::isLegalAddressingMode(const DataLayout &DL,
1886 const AddrMode &AM, Type *Ty,
1887 unsigned AS, Instruction *I) const {
1888 // The default implementation of this implements a conservative RISCy, r+r and
1889 // r+i addr mode.
1890
1891 // Scalable offsets not supported
1892 if (AM.ScalableOffset)
1893 return false;
1894
1895 // Allows a sign-extended 16-bit immediate field.
1896 if (AM.BaseOffs <= -(1LL << 16) || AM.BaseOffs >= (1LL << 16)-1)
1897 return false;
1898
1899 // No global is ever allowed as a base.
1900 if (AM.BaseGV)
1901 return false;
1902
1903 // Only support r+r,
1904 switch (AM.Scale) {
1905 case 0: // "r+i" or just "i", depending on HasBaseReg.
1906 break;
1907 case 1:
1908 if (AM.HasBaseReg && AM.BaseOffs) // "r+r+i" is not allowed.
1909 return false;
1910 // Otherwise we have r+r or r+i.
1911 break;
1912 case 2:
1913 if (AM.HasBaseReg || AM.BaseOffs) // 2*r+r or 2*r+i is not allowed.
1914 return false;
1915 // Allow 2*r as r+r.
1916 break;
1917 default: // Don't allow n * r
1918 return false;
1919 }
1920
1921 return true;
1922 }
1923
1924 //===----------------------------------------------------------------------===//
1925 // Stack Protector
1926 //===----------------------------------------------------------------------===//
1927
1928 // For OpenBSD return its special guard variable. Otherwise return nullptr,
1929 // so that SelectionDAG handle SSP.
getIRStackGuard(IRBuilderBase & IRB) const1930 Value *TargetLoweringBase::getIRStackGuard(IRBuilderBase &IRB) const {
1931 if (getTargetMachine().getTargetTriple().isOSOpenBSD()) {
1932 Module &M = *IRB.GetInsertBlock()->getParent()->getParent();
1933 PointerType *PtrTy = PointerType::getUnqual(M.getContext());
1934 Constant *C = M.getOrInsertGlobal("__guard_local", PtrTy);
1935 if (GlobalVariable *G = dyn_cast_or_null<GlobalVariable>(C))
1936 G->setVisibility(GlobalValue::HiddenVisibility);
1937 return C;
1938 }
1939 return nullptr;
1940 }
1941
1942 // Currently only support "standard" __stack_chk_guard.
1943 // TODO: add LOAD_STACK_GUARD support.
insertSSPDeclarations(Module & M) const1944 void TargetLoweringBase::insertSSPDeclarations(Module &M) const {
1945 if (!M.getNamedValue("__stack_chk_guard")) {
1946 auto *GV = new GlobalVariable(M, PointerType::getUnqual(M.getContext()),
1947 false, GlobalVariable::ExternalLinkage,
1948 nullptr, "__stack_chk_guard");
1949
1950 // FreeBSD has "__stack_chk_guard" defined externally on libc.so
1951 if (M.getDirectAccessExternalData() &&
1952 !TM.getTargetTriple().isWindowsGNUEnvironment() &&
1953 !(TM.getTargetTriple().isPPC64() &&
1954 TM.getTargetTriple().isOSFreeBSD()) &&
1955 (!TM.getTargetTriple().isOSDarwin() ||
1956 TM.getRelocationModel() == Reloc::Static))
1957 GV->setDSOLocal(true);
1958 }
1959 }
1960
1961 // Currently only support "standard" __stack_chk_guard.
1962 // TODO: add LOAD_STACK_GUARD support.
getSDagStackGuard(const Module & M) const1963 Value *TargetLoweringBase::getSDagStackGuard(const Module &M) const {
1964 return M.getNamedValue("__stack_chk_guard");
1965 }
1966
getSSPStackGuardCheck(const Module & M) const1967 Function *TargetLoweringBase::getSSPStackGuardCheck(const Module &M) const {
1968 return nullptr;
1969 }
1970
getMinimumJumpTableEntries() const1971 unsigned TargetLoweringBase::getMinimumJumpTableEntries() const {
1972 return MinimumJumpTableEntries;
1973 }
1974
setMinimumJumpTableEntries(unsigned Val)1975 void TargetLoweringBase::setMinimumJumpTableEntries(unsigned Val) {
1976 MinimumJumpTableEntries = Val;
1977 }
1978
getMinimumJumpTableDensity(bool OptForSize) const1979 unsigned TargetLoweringBase::getMinimumJumpTableDensity(bool OptForSize) const {
1980 return OptForSize ? OptsizeJumpTableDensity : JumpTableDensity;
1981 }
1982
getMaximumJumpTableSize() const1983 unsigned TargetLoweringBase::getMaximumJumpTableSize() const {
1984 return MaximumJumpTableSize;
1985 }
1986
setMaximumJumpTableSize(unsigned Val)1987 void TargetLoweringBase::setMaximumJumpTableSize(unsigned Val) {
1988 MaximumJumpTableSize = Val;
1989 }
1990
isJumpTableRelative() const1991 bool TargetLoweringBase::isJumpTableRelative() const {
1992 return getTargetMachine().isPositionIndependent();
1993 }
1994
getPrefLoopAlignment(MachineLoop * ML) const1995 Align TargetLoweringBase::getPrefLoopAlignment(MachineLoop *ML) const {
1996 if (TM.Options.LoopAlignment)
1997 return Align(TM.Options.LoopAlignment);
1998 return PrefLoopAlignment;
1999 }
2000
getMaxPermittedBytesForAlignment(MachineBasicBlock * MBB) const2001 unsigned TargetLoweringBase::getMaxPermittedBytesForAlignment(
2002 MachineBasicBlock *MBB) const {
2003 return MaxBytesForAlignment;
2004 }
2005
2006 //===----------------------------------------------------------------------===//
2007 // Reciprocal Estimates
2008 //===----------------------------------------------------------------------===//
2009
2010 /// Get the reciprocal estimate attribute string for a function that will
2011 /// override the target defaults.
getRecipEstimateForFunc(MachineFunction & MF)2012 static StringRef getRecipEstimateForFunc(MachineFunction &MF) {
2013 const Function &F = MF.getFunction();
2014 return F.getFnAttribute("reciprocal-estimates").getValueAsString();
2015 }
2016
2017 /// Construct a string for the given reciprocal operation of the given type.
2018 /// This string should match the corresponding option to the front-end's
2019 /// "-mrecip" flag assuming those strings have been passed through in an
2020 /// attribute string. For example, "vec-divf" for a division of a vXf32.
getReciprocalOpName(bool IsSqrt,EVT VT)2021 static std::string getReciprocalOpName(bool IsSqrt, EVT VT) {
2022 std::string Name = VT.isVector() ? "vec-" : "";
2023
2024 Name += IsSqrt ? "sqrt" : "div";
2025
2026 // TODO: Handle other float types?
2027 if (VT.getScalarType() == MVT::f64) {
2028 Name += "d";
2029 } else if (VT.getScalarType() == MVT::f16) {
2030 Name += "h";
2031 } else {
2032 assert(VT.getScalarType() == MVT::f32 &&
2033 "Unexpected FP type for reciprocal estimate");
2034 Name += "f";
2035 }
2036
2037 return Name;
2038 }
2039
2040 /// Return the character position and value (a single numeric character) of a
2041 /// customized refinement operation in the input string if it exists. Return
2042 /// false if there is no customized refinement step count.
parseRefinementStep(StringRef In,size_t & Position,uint8_t & Value)2043 static bool parseRefinementStep(StringRef In, size_t &Position,
2044 uint8_t &Value) {
2045 const char RefStepToken = ':';
2046 Position = In.find(RefStepToken);
2047 if (Position == StringRef::npos)
2048 return false;
2049
2050 StringRef RefStepString = In.substr(Position + 1);
2051 // Allow exactly one numeric character for the additional refinement
2052 // step parameter.
2053 if (RefStepString.size() == 1) {
2054 char RefStepChar = RefStepString[0];
2055 if (isDigit(RefStepChar)) {
2056 Value = RefStepChar - '0';
2057 return true;
2058 }
2059 }
2060 report_fatal_error("Invalid refinement step for -recip.");
2061 }
2062
2063 /// For the input attribute string, return one of the ReciprocalEstimate enum
2064 /// status values (enabled, disabled, or not specified) for this operation on
2065 /// the specified data type.
getOpEnabled(bool IsSqrt,EVT VT,StringRef Override)2066 static int getOpEnabled(bool IsSqrt, EVT VT, StringRef Override) {
2067 if (Override.empty())
2068 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2069
2070 SmallVector<StringRef, 4> OverrideVector;
2071 Override.split(OverrideVector, ',');
2072 unsigned NumArgs = OverrideVector.size();
2073
2074 // Check if "all", "none", or "default" was specified.
2075 if (NumArgs == 1) {
2076 // Look for an optional setting of the number of refinement steps needed
2077 // for this type of reciprocal operation.
2078 size_t RefPos;
2079 uint8_t RefSteps;
2080 if (parseRefinementStep(Override, RefPos, RefSteps)) {
2081 // Split the string for further processing.
2082 Override = Override.substr(0, RefPos);
2083 }
2084
2085 // All reciprocal types are enabled.
2086 if (Override == "all")
2087 return TargetLoweringBase::ReciprocalEstimate::Enabled;
2088
2089 // All reciprocal types are disabled.
2090 if (Override == "none")
2091 return TargetLoweringBase::ReciprocalEstimate::Disabled;
2092
2093 // Target defaults for enablement are used.
2094 if (Override == "default")
2095 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2096 }
2097
2098 // The attribute string may omit the size suffix ('f'/'d').
2099 std::string VTName = getReciprocalOpName(IsSqrt, VT);
2100 std::string VTNameNoSize = VTName;
2101 VTNameNoSize.pop_back();
2102 static const char DisabledPrefix = '!';
2103
2104 for (StringRef RecipType : OverrideVector) {
2105 size_t RefPos;
2106 uint8_t RefSteps;
2107 if (parseRefinementStep(RecipType, RefPos, RefSteps))
2108 RecipType = RecipType.substr(0, RefPos);
2109
2110 // Ignore the disablement token for string matching.
2111 bool IsDisabled = RecipType[0] == DisabledPrefix;
2112 if (IsDisabled)
2113 RecipType = RecipType.substr(1);
2114
2115 if (RecipType == VTName || RecipType == VTNameNoSize)
2116 return IsDisabled ? TargetLoweringBase::ReciprocalEstimate::Disabled
2117 : TargetLoweringBase::ReciprocalEstimate::Enabled;
2118 }
2119
2120 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2121 }
2122
2123 /// For the input attribute string, return the customized refinement step count
2124 /// for this operation on the specified data type. If the step count does not
2125 /// exist, return the ReciprocalEstimate enum value for unspecified.
getOpRefinementSteps(bool IsSqrt,EVT VT,StringRef Override)2126 static int getOpRefinementSteps(bool IsSqrt, EVT VT, StringRef Override) {
2127 if (Override.empty())
2128 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2129
2130 SmallVector<StringRef, 4> OverrideVector;
2131 Override.split(OverrideVector, ',');
2132 unsigned NumArgs = OverrideVector.size();
2133
2134 // Check if "all", "default", or "none" was specified.
2135 if (NumArgs == 1) {
2136 // Look for an optional setting of the number of refinement steps needed
2137 // for this type of reciprocal operation.
2138 size_t RefPos;
2139 uint8_t RefSteps;
2140 if (!parseRefinementStep(Override, RefPos, RefSteps))
2141 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2142
2143 // Split the string for further processing.
2144 Override = Override.substr(0, RefPos);
2145 assert(Override != "none" &&
2146 "Disabled reciprocals, but specifed refinement steps?");
2147
2148 // If this is a general override, return the specified number of steps.
2149 if (Override == "all" || Override == "default")
2150 return RefSteps;
2151 }
2152
2153 // The attribute string may omit the size suffix ('f'/'d').
2154 std::string VTName = getReciprocalOpName(IsSqrt, VT);
2155 std::string VTNameNoSize = VTName;
2156 VTNameNoSize.pop_back();
2157
2158 for (StringRef RecipType : OverrideVector) {
2159 size_t RefPos;
2160 uint8_t RefSteps;
2161 if (!parseRefinementStep(RecipType, RefPos, RefSteps))
2162 continue;
2163
2164 RecipType = RecipType.substr(0, RefPos);
2165 if (RecipType == VTName || RecipType == VTNameNoSize)
2166 return RefSteps;
2167 }
2168
2169 return TargetLoweringBase::ReciprocalEstimate::Unspecified;
2170 }
2171
getRecipEstimateSqrtEnabled(EVT VT,MachineFunction & MF) const2172 int TargetLoweringBase::getRecipEstimateSqrtEnabled(EVT VT,
2173 MachineFunction &MF) const {
2174 return getOpEnabled(true, VT, getRecipEstimateForFunc(MF));
2175 }
2176
getRecipEstimateDivEnabled(EVT VT,MachineFunction & MF) const2177 int TargetLoweringBase::getRecipEstimateDivEnabled(EVT VT,
2178 MachineFunction &MF) const {
2179 return getOpEnabled(false, VT, getRecipEstimateForFunc(MF));
2180 }
2181
getSqrtRefinementSteps(EVT VT,MachineFunction & MF) const2182 int TargetLoweringBase::getSqrtRefinementSteps(EVT VT,
2183 MachineFunction &MF) const {
2184 return getOpRefinementSteps(true, VT, getRecipEstimateForFunc(MF));
2185 }
2186
getDivRefinementSteps(EVT VT,MachineFunction & MF) const2187 int TargetLoweringBase::getDivRefinementSteps(EVT VT,
2188 MachineFunction &MF) const {
2189 return getOpRefinementSteps(false, VT, getRecipEstimateForFunc(MF));
2190 }
2191
isLoadBitCastBeneficial(EVT LoadVT,EVT BitcastVT,const SelectionDAG & DAG,const MachineMemOperand & MMO) const2192 bool TargetLoweringBase::isLoadBitCastBeneficial(
2193 EVT LoadVT, EVT BitcastVT, const SelectionDAG &DAG,
2194 const MachineMemOperand &MMO) const {
2195 // Single-element vectors are scalarized, so we should generally avoid having
2196 // any memory operations on such types, as they would get scalarized too.
2197 if (LoadVT.isFixedLengthVector() && BitcastVT.isFixedLengthVector() &&
2198 BitcastVT.getVectorNumElements() == 1)
2199 return false;
2200
2201 // Don't do if we could do an indexed load on the original type, but not on
2202 // the new one.
2203 if (!LoadVT.isSimple() || !BitcastVT.isSimple())
2204 return true;
2205
2206 MVT LoadMVT = LoadVT.getSimpleVT();
2207
2208 // Don't bother doing this if it's just going to be promoted again later, as
2209 // doing so might interfere with other combines.
2210 if (getOperationAction(ISD::LOAD, LoadMVT) == Promote &&
2211 getTypeToPromoteTo(ISD::LOAD, LoadMVT) == BitcastVT.getSimpleVT())
2212 return false;
2213
2214 unsigned Fast = 0;
2215 return allowsMemoryAccess(*DAG.getContext(), DAG.getDataLayout(), BitcastVT,
2216 MMO, &Fast) &&
2217 Fast;
2218 }
2219
finalizeLowering(MachineFunction & MF) const2220 void TargetLoweringBase::finalizeLowering(MachineFunction &MF) const {
2221 MF.getRegInfo().freezeReservedRegs();
2222 }
2223
getLoadMemOperandFlags(const LoadInst & LI,const DataLayout & DL,AssumptionCache * AC,const TargetLibraryInfo * LibInfo) const2224 MachineMemOperand::Flags TargetLoweringBase::getLoadMemOperandFlags(
2225 const LoadInst &LI, const DataLayout &DL, AssumptionCache *AC,
2226 const TargetLibraryInfo *LibInfo) const {
2227 MachineMemOperand::Flags Flags = MachineMemOperand::MOLoad;
2228 if (LI.isVolatile())
2229 Flags |= MachineMemOperand::MOVolatile;
2230
2231 if (LI.hasMetadata(LLVMContext::MD_nontemporal))
2232 Flags |= MachineMemOperand::MONonTemporal;
2233
2234 if (LI.hasMetadata(LLVMContext::MD_invariant_load))
2235 Flags |= MachineMemOperand::MOInvariant;
2236
2237 if (isDereferenceableAndAlignedPointer(LI.getPointerOperand(), LI.getType(),
2238 LI.getAlign(), DL, &LI, AC,
2239 /*DT=*/nullptr, LibInfo))
2240 Flags |= MachineMemOperand::MODereferenceable;
2241
2242 Flags |= getTargetMMOFlags(LI);
2243 return Flags;
2244 }
2245
2246 MachineMemOperand::Flags
getStoreMemOperandFlags(const StoreInst & SI,const DataLayout & DL) const2247 TargetLoweringBase::getStoreMemOperandFlags(const StoreInst &SI,
2248 const DataLayout &DL) const {
2249 MachineMemOperand::Flags Flags = MachineMemOperand::MOStore;
2250
2251 if (SI.isVolatile())
2252 Flags |= MachineMemOperand::MOVolatile;
2253
2254 if (SI.hasMetadata(LLVMContext::MD_nontemporal))
2255 Flags |= MachineMemOperand::MONonTemporal;
2256
2257 // FIXME: Not preserving dereferenceable
2258 Flags |= getTargetMMOFlags(SI);
2259 return Flags;
2260 }
2261
2262 MachineMemOperand::Flags
getAtomicMemOperandFlags(const Instruction & AI,const DataLayout & DL) const2263 TargetLoweringBase::getAtomicMemOperandFlags(const Instruction &AI,
2264 const DataLayout &DL) const {
2265 auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore;
2266
2267 if (const AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(&AI)) {
2268 if (RMW->isVolatile())
2269 Flags |= MachineMemOperand::MOVolatile;
2270 } else if (const AtomicCmpXchgInst *CmpX = dyn_cast<AtomicCmpXchgInst>(&AI)) {
2271 if (CmpX->isVolatile())
2272 Flags |= MachineMemOperand::MOVolatile;
2273 } else
2274 llvm_unreachable("not an atomic instruction");
2275
2276 // FIXME: Not preserving dereferenceable
2277 Flags |= getTargetMMOFlags(AI);
2278 return Flags;
2279 }
2280
emitLeadingFence(IRBuilderBase & Builder,Instruction * Inst,AtomicOrdering Ord) const2281 Instruction *TargetLoweringBase::emitLeadingFence(IRBuilderBase &Builder,
2282 Instruction *Inst,
2283 AtomicOrdering Ord) const {
2284 if (isReleaseOrStronger(Ord) && Inst->hasAtomicStore())
2285 return Builder.CreateFence(Ord);
2286 else
2287 return nullptr;
2288 }
2289
emitTrailingFence(IRBuilderBase & Builder,Instruction * Inst,AtomicOrdering Ord) const2290 Instruction *TargetLoweringBase::emitTrailingFence(IRBuilderBase &Builder,
2291 Instruction *Inst,
2292 AtomicOrdering Ord) const {
2293 if (isAcquireOrStronger(Ord))
2294 return Builder.CreateFence(Ord);
2295 else
2296 return nullptr;
2297 }
2298
2299 //===----------------------------------------------------------------------===//
2300 // GlobalISel Hooks
2301 //===----------------------------------------------------------------------===//
2302
shouldLocalize(const MachineInstr & MI,const TargetTransformInfo * TTI) const2303 bool TargetLoweringBase::shouldLocalize(const MachineInstr &MI,
2304 const TargetTransformInfo *TTI) const {
2305 auto &MF = *MI.getMF();
2306 auto &MRI = MF.getRegInfo();
2307 // Assuming a spill and reload of a value has a cost of 1 instruction each,
2308 // this helper function computes the maximum number of uses we should consider
2309 // for remat. E.g. on arm64 global addresses take 2 insts to materialize. We
2310 // break even in terms of code size when the original MI has 2 users vs
2311 // choosing to potentially spill. Any more than 2 users we we have a net code
2312 // size increase. This doesn't take into account register pressure though.
2313 auto maxUses = [](unsigned RematCost) {
2314 // A cost of 1 means remats are basically free.
2315 if (RematCost == 1)
2316 return std::numeric_limits<unsigned>::max();
2317 if (RematCost == 2)
2318 return 2U;
2319
2320 // Remat is too expensive, only sink if there's one user.
2321 if (RematCost > 2)
2322 return 1U;
2323 llvm_unreachable("Unexpected remat cost");
2324 };
2325
2326 switch (MI.getOpcode()) {
2327 default:
2328 return false;
2329 // Constants-like instructions should be close to their users.
2330 // We don't want long live-ranges for them.
2331 case TargetOpcode::G_CONSTANT:
2332 case TargetOpcode::G_FCONSTANT:
2333 case TargetOpcode::G_FRAME_INDEX:
2334 case TargetOpcode::G_INTTOPTR:
2335 return true;
2336 case TargetOpcode::G_GLOBAL_VALUE: {
2337 unsigned RematCost = TTI->getGISelRematGlobalCost();
2338 Register Reg = MI.getOperand(0).getReg();
2339 unsigned MaxUses = maxUses(RematCost);
2340 if (MaxUses == UINT_MAX)
2341 return true; // Remats are "free" so always localize.
2342 return MRI.hasAtMostUserInstrs(Reg, MaxUses);
2343 }
2344 }
2345 }
2346