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/Triple.h"
19 #include "llvm/ADT/Twine.h"
20 #include "llvm/CodeGen/Analysis.h"
21 #include "llvm/CodeGen/ISDOpcodes.h"
22 #include "llvm/CodeGen/MachineBasicBlock.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineInstr.h"
26 #include "llvm/CodeGen/MachineInstrBuilder.h"
27 #include "llvm/CodeGen/MachineMemOperand.h"
28 #include "llvm/CodeGen/MachineOperand.h"
29 #include "llvm/CodeGen/MachineRegisterInfo.h"
30 #include "llvm/CodeGen/RuntimeLibcalls.h"
31 #include "llvm/CodeGen/StackMaps.h"
32 #include "llvm/CodeGen/TargetLowering.h"
33 #include "llvm/CodeGen/TargetOpcodes.h"
34 #include "llvm/CodeGen/TargetRegisterInfo.h"
35 #include "llvm/CodeGen/ValueTypes.h"
36 #include "llvm/IR/Attributes.h"
37 #include "llvm/IR/CallingConv.h"
38 #include "llvm/IR/DataLayout.h"
39 #include "llvm/IR/DerivedTypes.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/IR/GlobalValue.h"
42 #include "llvm/IR/GlobalVariable.h"
43 #include "llvm/IR/IRBuilder.h"
44 #include "llvm/IR/Module.h"
45 #include "llvm/IR/Type.h"
46 #include "llvm/Support/BranchProbability.h"
47 #include "llvm/Support/Casting.h"
48 #include "llvm/Support/CommandLine.h"
49 #include "llvm/Support/Compiler.h"
50 #include "llvm/Support/ErrorHandling.h"
51 #include "llvm/Support/MachineValueType.h"
52 #include "llvm/Support/MathExtras.h"
53 #include "llvm/Target/TargetMachine.h"
54 #include <algorithm>
55 #include <cassert>
56 #include <cstddef>
57 #include <cstdint>
58 #include <cstring>
59 #include <iterator>
60 #include <string>
61 #include <tuple>
62 #include <utility>
63 
64 using namespace llvm;
65 
66 static cl::opt<bool> JumpIsExpensiveOverride(
67     "jump-is-expensive", cl::init(false),
68     cl::desc("Do not create extra branches to split comparison logic."),
69     cl::Hidden);
70 
71 static cl::opt<unsigned> MinimumJumpTableEntries
72   ("min-jump-table-entries", cl::init(4), cl::Hidden,
73    cl::desc("Set minimum number of entries to use a jump table."));
74 
75 static cl::opt<unsigned> MaximumJumpTableSize
76   ("max-jump-table-size", cl::init(UINT_MAX), cl::Hidden,
77    cl::desc("Set maximum size of jump tables."));
78 
79 /// Minimum jump table density for normal functions.
80 static cl::opt<unsigned>
81     JumpTableDensity("jump-table-density", cl::init(10), cl::Hidden,
82                      cl::desc("Minimum density for building a jump table in "
83                               "a normal function"));
84 
85 /// Minimum jump table density for -Os or -Oz functions.
86 static cl::opt<unsigned> OptsizeJumpTableDensity(
87     "optsize-jump-table-density", cl::init(40), cl::Hidden,
88     cl::desc("Minimum density for building a jump table in "
89              "an optsize function"));
90 
91 static bool darwinHasSinCos(const Triple &TT) {
92   assert(TT.isOSDarwin() && "should be called with darwin triple");
93   // Don't bother with 32 bit x86.
94   if (TT.getArch() == Triple::x86)
95     return false;
96   // Macos < 10.9 has no sincos_stret.
97   if (TT.isMacOSX())
98     return !TT.isMacOSXVersionLT(10, 9) && TT.isArch64Bit();
99   // iOS < 7.0 has no sincos_stret.
100   if (TT.isiOS())
101     return !TT.isOSVersionLT(7, 0);
102   // Any other darwin such as WatchOS/TvOS is new enough.
103   return true;
104 }
105 
106 // Although this default value is arbitrary, it is not random. It is assumed
107 // that a condition that evaluates the same way by a higher percentage than this
108 // is best represented as control flow. Therefore, the default value N should be
109 // set such that the win from N% correct executions is greater than the loss
110 // from (100 - N)% mispredicted executions for the majority of intended targets.
111 static cl::opt<int> MinPercentageForPredictableBranch(
112     "min-predictable-branch", cl::init(99),
113     cl::desc("Minimum percentage (0-100) that a condition must be either true "
114              "or false to assume that the condition is predictable"),
115     cl::Hidden);
116 
117 void TargetLoweringBase::InitLibcalls(const Triple &TT) {
118 #define HANDLE_LIBCALL(code, name) \
119   setLibcallName(RTLIB::code, name);
120 #include "llvm/IR/RuntimeLibcalls.def"
121 #undef HANDLE_LIBCALL
122   // Initialize calling conventions to their default.
123   for (int LC = 0; LC < RTLIB::UNKNOWN_LIBCALL; ++LC)
124     setLibcallCallingConv((RTLIB::Libcall)LC, CallingConv::C);
125 
126   // A few names are different on particular architectures or environments.
127   if (TT.isOSDarwin()) {
128     // For f16/f32 conversions, Darwin uses the standard naming scheme, instead
129     // of the gnueabi-style __gnu_*_ieee.
130     // FIXME: What about other targets?
131     setLibcallName(RTLIB::FPEXT_F16_F32, "__extendhfsf2");
132     setLibcallName(RTLIB::FPROUND_F32_F16, "__truncsfhf2");
133 
134     // Some darwins have an optimized __bzero/bzero function.
135     switch (TT.getArch()) {
136     case Triple::x86:
137     case Triple::x86_64:
138       if (TT.isMacOSX() && !TT.isMacOSXVersionLT(10, 6))
139         setLibcallName(RTLIB::BZERO, "__bzero");
140       break;
141     case Triple::aarch64:
142       setLibcallName(RTLIB::BZERO, "bzero");
143       break;
144     default:
145       break;
146     }
147 
148     if (darwinHasSinCos(TT)) {
149       setLibcallName(RTLIB::SINCOS_STRET_F32, "__sincosf_stret");
150       setLibcallName(RTLIB::SINCOS_STRET_F64, "__sincos_stret");
151       if (TT.isWatchABI()) {
152         setLibcallCallingConv(RTLIB::SINCOS_STRET_F32,
153                               CallingConv::ARM_AAPCS_VFP);
154         setLibcallCallingConv(RTLIB::SINCOS_STRET_F64,
155                               CallingConv::ARM_AAPCS_VFP);
156       }
157     }
158   } else {
159     setLibcallName(RTLIB::FPEXT_F16_F32, "__gnu_h2f_ieee");
160     setLibcallName(RTLIB::FPROUND_F32_F16, "__gnu_f2h_ieee");
161   }
162 
163   if (TT.isGNUEnvironment() || TT.isOSFuchsia() ||
164       (TT.isAndroid() && !TT.isAndroidVersionLT(9))) {
165     setLibcallName(RTLIB::SINCOS_F32, "sincosf");
166     setLibcallName(RTLIB::SINCOS_F64, "sincos");
167     setLibcallName(RTLIB::SINCOS_F80, "sincosl");
168     setLibcallName(RTLIB::SINCOS_F128, "sincosl");
169     setLibcallName(RTLIB::SINCOS_PPCF128, "sincosl");
170   }
171 
172   if (TT.isOSOpenBSD()) {
173     setLibcallName(RTLIB::STACKPROTECTOR_CHECK_FAIL, nullptr);
174   }
175 }
176 
177 /// getFPEXT - Return the FPEXT_*_* value for the given types, or
178 /// UNKNOWN_LIBCALL if there is none.
179 RTLIB::Libcall RTLIB::getFPEXT(EVT OpVT, EVT RetVT) {
180   if (OpVT == MVT::f16) {
181     if (RetVT == MVT::f32)
182       return FPEXT_F16_F32;
183   } else if (OpVT == MVT::f32) {
184     if (RetVT == MVT::f64)
185       return FPEXT_F32_F64;
186     if (RetVT == MVT::f128)
187       return FPEXT_F32_F128;
188     if (RetVT == MVT::ppcf128)
189       return FPEXT_F32_PPCF128;
190   } else if (OpVT == MVT::f64) {
191     if (RetVT == MVT::f128)
192       return FPEXT_F64_F128;
193     else if (RetVT == MVT::ppcf128)
194       return FPEXT_F64_PPCF128;
195   } else if (OpVT == MVT::f80) {
196     if (RetVT == MVT::f128)
197       return FPEXT_F80_F128;
198   }
199 
200   return UNKNOWN_LIBCALL;
201 }
202 
203 /// getFPROUND - Return the FPROUND_*_* value for the given types, or
204 /// UNKNOWN_LIBCALL if there is none.
205 RTLIB::Libcall RTLIB::getFPROUND(EVT OpVT, EVT RetVT) {
206   if (RetVT == MVT::f16) {
207     if (OpVT == MVT::f32)
208       return FPROUND_F32_F16;
209     if (OpVT == MVT::f64)
210       return FPROUND_F64_F16;
211     if (OpVT == MVT::f80)
212       return FPROUND_F80_F16;
213     if (OpVT == MVT::f128)
214       return FPROUND_F128_F16;
215     if (OpVT == MVT::ppcf128)
216       return FPROUND_PPCF128_F16;
217   } else if (RetVT == MVT::f32) {
218     if (OpVT == MVT::f64)
219       return FPROUND_F64_F32;
220     if (OpVT == MVT::f80)
221       return FPROUND_F80_F32;
222     if (OpVT == MVT::f128)
223       return FPROUND_F128_F32;
224     if (OpVT == MVT::ppcf128)
225       return FPROUND_PPCF128_F32;
226   } else if (RetVT == MVT::f64) {
227     if (OpVT == MVT::f80)
228       return FPROUND_F80_F64;
229     if (OpVT == MVT::f128)
230       return FPROUND_F128_F64;
231     if (OpVT == MVT::ppcf128)
232       return FPROUND_PPCF128_F64;
233   } else if (RetVT == MVT::f80) {
234     if (OpVT == MVT::f128)
235       return FPROUND_F128_F80;
236   }
237 
238   return UNKNOWN_LIBCALL;
239 }
240 
241 /// getFPTOSINT - Return the FPTOSINT_*_* value for the given types, or
242 /// UNKNOWN_LIBCALL if there is none.
243 RTLIB::Libcall RTLIB::getFPTOSINT(EVT OpVT, EVT RetVT) {
244   if (OpVT == MVT::f32) {
245     if (RetVT == MVT::i32)
246       return FPTOSINT_F32_I32;
247     if (RetVT == MVT::i64)
248       return FPTOSINT_F32_I64;
249     if (RetVT == MVT::i128)
250       return FPTOSINT_F32_I128;
251   } else if (OpVT == MVT::f64) {
252     if (RetVT == MVT::i32)
253       return FPTOSINT_F64_I32;
254     if (RetVT == MVT::i64)
255       return FPTOSINT_F64_I64;
256     if (RetVT == MVT::i128)
257       return FPTOSINT_F64_I128;
258   } else if (OpVT == MVT::f80) {
259     if (RetVT == MVT::i32)
260       return FPTOSINT_F80_I32;
261     if (RetVT == MVT::i64)
262       return FPTOSINT_F80_I64;
263     if (RetVT == MVT::i128)
264       return FPTOSINT_F80_I128;
265   } else if (OpVT == MVT::f128) {
266     if (RetVT == MVT::i32)
267       return FPTOSINT_F128_I32;
268     if (RetVT == MVT::i64)
269       return FPTOSINT_F128_I64;
270     if (RetVT == MVT::i128)
271       return FPTOSINT_F128_I128;
272   } else if (OpVT == MVT::ppcf128) {
273     if (RetVT == MVT::i32)
274       return FPTOSINT_PPCF128_I32;
275     if (RetVT == MVT::i64)
276       return FPTOSINT_PPCF128_I64;
277     if (RetVT == MVT::i128)
278       return FPTOSINT_PPCF128_I128;
279   }
280   return UNKNOWN_LIBCALL;
281 }
282 
283 /// getFPTOUINT - Return the FPTOUINT_*_* value for the given types, or
284 /// UNKNOWN_LIBCALL if there is none.
285 RTLIB::Libcall RTLIB::getFPTOUINT(EVT OpVT, EVT RetVT) {
286   if (OpVT == MVT::f32) {
287     if (RetVT == MVT::i32)
288       return FPTOUINT_F32_I32;
289     if (RetVT == MVT::i64)
290       return FPTOUINT_F32_I64;
291     if (RetVT == MVT::i128)
292       return FPTOUINT_F32_I128;
293   } else if (OpVT == MVT::f64) {
294     if (RetVT == MVT::i32)
295       return FPTOUINT_F64_I32;
296     if (RetVT == MVT::i64)
297       return FPTOUINT_F64_I64;
298     if (RetVT == MVT::i128)
299       return FPTOUINT_F64_I128;
300   } else if (OpVT == MVT::f80) {
301     if (RetVT == MVT::i32)
302       return FPTOUINT_F80_I32;
303     if (RetVT == MVT::i64)
304       return FPTOUINT_F80_I64;
305     if (RetVT == MVT::i128)
306       return FPTOUINT_F80_I128;
307   } else if (OpVT == MVT::f128) {
308     if (RetVT == MVT::i32)
309       return FPTOUINT_F128_I32;
310     if (RetVT == MVT::i64)
311       return FPTOUINT_F128_I64;
312     if (RetVT == MVT::i128)
313       return FPTOUINT_F128_I128;
314   } else if (OpVT == MVT::ppcf128) {
315     if (RetVT == MVT::i32)
316       return FPTOUINT_PPCF128_I32;
317     if (RetVT == MVT::i64)
318       return FPTOUINT_PPCF128_I64;
319     if (RetVT == MVT::i128)
320       return FPTOUINT_PPCF128_I128;
321   }
322   return UNKNOWN_LIBCALL;
323 }
324 
325 /// getSINTTOFP - Return the SINTTOFP_*_* value for the given types, or
326 /// UNKNOWN_LIBCALL if there is none.
327 RTLIB::Libcall RTLIB::getSINTTOFP(EVT OpVT, EVT RetVT) {
328   if (OpVT == MVT::i32) {
329     if (RetVT == MVT::f32)
330       return SINTTOFP_I32_F32;
331     if (RetVT == MVT::f64)
332       return SINTTOFP_I32_F64;
333     if (RetVT == MVT::f80)
334       return SINTTOFP_I32_F80;
335     if (RetVT == MVT::f128)
336       return SINTTOFP_I32_F128;
337     if (RetVT == MVT::ppcf128)
338       return SINTTOFP_I32_PPCF128;
339   } else if (OpVT == MVT::i64) {
340     if (RetVT == MVT::f32)
341       return SINTTOFP_I64_F32;
342     if (RetVT == MVT::f64)
343       return SINTTOFP_I64_F64;
344     if (RetVT == MVT::f80)
345       return SINTTOFP_I64_F80;
346     if (RetVT == MVT::f128)
347       return SINTTOFP_I64_F128;
348     if (RetVT == MVT::ppcf128)
349       return SINTTOFP_I64_PPCF128;
350   } else if (OpVT == MVT::i128) {
351     if (RetVT == MVT::f32)
352       return SINTTOFP_I128_F32;
353     if (RetVT == MVT::f64)
354       return SINTTOFP_I128_F64;
355     if (RetVT == MVT::f80)
356       return SINTTOFP_I128_F80;
357     if (RetVT == MVT::f128)
358       return SINTTOFP_I128_F128;
359     if (RetVT == MVT::ppcf128)
360       return SINTTOFP_I128_PPCF128;
361   }
362   return UNKNOWN_LIBCALL;
363 }
364 
365 /// getUINTTOFP - Return the UINTTOFP_*_* value for the given types, or
366 /// UNKNOWN_LIBCALL if there is none.
367 RTLIB::Libcall RTLIB::getUINTTOFP(EVT OpVT, EVT RetVT) {
368   if (OpVT == MVT::i32) {
369     if (RetVT == MVT::f32)
370       return UINTTOFP_I32_F32;
371     if (RetVT == MVT::f64)
372       return UINTTOFP_I32_F64;
373     if (RetVT == MVT::f80)
374       return UINTTOFP_I32_F80;
375     if (RetVT == MVT::f128)
376       return UINTTOFP_I32_F128;
377     if (RetVT == MVT::ppcf128)
378       return UINTTOFP_I32_PPCF128;
379   } else if (OpVT == MVT::i64) {
380     if (RetVT == MVT::f32)
381       return UINTTOFP_I64_F32;
382     if (RetVT == MVT::f64)
383       return UINTTOFP_I64_F64;
384     if (RetVT == MVT::f80)
385       return UINTTOFP_I64_F80;
386     if (RetVT == MVT::f128)
387       return UINTTOFP_I64_F128;
388     if (RetVT == MVT::ppcf128)
389       return UINTTOFP_I64_PPCF128;
390   } else if (OpVT == MVT::i128) {
391     if (RetVT == MVT::f32)
392       return UINTTOFP_I128_F32;
393     if (RetVT == MVT::f64)
394       return UINTTOFP_I128_F64;
395     if (RetVT == MVT::f80)
396       return UINTTOFP_I128_F80;
397     if (RetVT == MVT::f128)
398       return UINTTOFP_I128_F128;
399     if (RetVT == MVT::ppcf128)
400       return UINTTOFP_I128_PPCF128;
401   }
402   return UNKNOWN_LIBCALL;
403 }
404 
405 RTLIB::Libcall RTLIB::getSYNC(unsigned Opc, MVT VT) {
406 #define OP_TO_LIBCALL(Name, Enum)                                              \
407   case Name:                                                                   \
408     switch (VT.SimpleTy) {                                                     \
409     default:                                                                   \
410       return UNKNOWN_LIBCALL;                                                  \
411     case MVT::i8:                                                              \
412       return Enum##_1;                                                         \
413     case MVT::i16:                                                             \
414       return Enum##_2;                                                         \
415     case MVT::i32:                                                             \
416       return Enum##_4;                                                         \
417     case MVT::i64:                                                             \
418       return Enum##_8;                                                         \
419     case MVT::i128:                                                            \
420       return Enum##_16;                                                        \
421     }
422 
423   switch (Opc) {
424     OP_TO_LIBCALL(ISD::ATOMIC_SWAP, SYNC_LOCK_TEST_AND_SET)
425     OP_TO_LIBCALL(ISD::ATOMIC_CMP_SWAP, SYNC_VAL_COMPARE_AND_SWAP)
426     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_ADD, SYNC_FETCH_AND_ADD)
427     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_SUB, SYNC_FETCH_AND_SUB)
428     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_AND, SYNC_FETCH_AND_AND)
429     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_OR, SYNC_FETCH_AND_OR)
430     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_XOR, SYNC_FETCH_AND_XOR)
431     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_NAND, SYNC_FETCH_AND_NAND)
432     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_MAX, SYNC_FETCH_AND_MAX)
433     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_UMAX, SYNC_FETCH_AND_UMAX)
434     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_MIN, SYNC_FETCH_AND_MIN)
435     OP_TO_LIBCALL(ISD::ATOMIC_LOAD_UMIN, SYNC_FETCH_AND_UMIN)
436   }
437 
438 #undef OP_TO_LIBCALL
439 
440   return UNKNOWN_LIBCALL;
441 }
442 
443 RTLIB::Libcall RTLIB::getMEMCPY_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
444   switch (ElementSize) {
445   case 1:
446     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_1;
447   case 2:
448     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_2;
449   case 4:
450     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_4;
451   case 8:
452     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_8;
453   case 16:
454     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_16;
455   default:
456     return UNKNOWN_LIBCALL;
457   }
458 }
459 
460 RTLIB::Libcall RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
461   switch (ElementSize) {
462   case 1:
463     return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_1;
464   case 2:
465     return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_2;
466   case 4:
467     return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_4;
468   case 8:
469     return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_8;
470   case 16:
471     return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_16;
472   default:
473     return UNKNOWN_LIBCALL;
474   }
475 }
476 
477 RTLIB::Libcall RTLIB::getMEMSET_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
478   switch (ElementSize) {
479   case 1:
480     return MEMSET_ELEMENT_UNORDERED_ATOMIC_1;
481   case 2:
482     return MEMSET_ELEMENT_UNORDERED_ATOMIC_2;
483   case 4:
484     return MEMSET_ELEMENT_UNORDERED_ATOMIC_4;
485   case 8:
486     return MEMSET_ELEMENT_UNORDERED_ATOMIC_8;
487   case 16:
488     return MEMSET_ELEMENT_UNORDERED_ATOMIC_16;
489   default:
490     return UNKNOWN_LIBCALL;
491   }
492 }
493 
494 /// InitCmpLibcallCCs - Set default comparison libcall CC.
495 static void InitCmpLibcallCCs(ISD::CondCode *CCs) {
496   memset(CCs, ISD::SETCC_INVALID, sizeof(ISD::CondCode)*RTLIB::UNKNOWN_LIBCALL);
497   CCs[RTLIB::OEQ_F32] = ISD::SETEQ;
498   CCs[RTLIB::OEQ_F64] = ISD::SETEQ;
499   CCs[RTLIB::OEQ_F128] = ISD::SETEQ;
500   CCs[RTLIB::OEQ_PPCF128] = ISD::SETEQ;
501   CCs[RTLIB::UNE_F32] = ISD::SETNE;
502   CCs[RTLIB::UNE_F64] = ISD::SETNE;
503   CCs[RTLIB::UNE_F128] = ISD::SETNE;
504   CCs[RTLIB::UNE_PPCF128] = ISD::SETNE;
505   CCs[RTLIB::OGE_F32] = ISD::SETGE;
506   CCs[RTLIB::OGE_F64] = ISD::SETGE;
507   CCs[RTLIB::OGE_F128] = ISD::SETGE;
508   CCs[RTLIB::OGE_PPCF128] = ISD::SETGE;
509   CCs[RTLIB::OLT_F32] = ISD::SETLT;
510   CCs[RTLIB::OLT_F64] = ISD::SETLT;
511   CCs[RTLIB::OLT_F128] = ISD::SETLT;
512   CCs[RTLIB::OLT_PPCF128] = ISD::SETLT;
513   CCs[RTLIB::OLE_F32] = ISD::SETLE;
514   CCs[RTLIB::OLE_F64] = ISD::SETLE;
515   CCs[RTLIB::OLE_F128] = ISD::SETLE;
516   CCs[RTLIB::OLE_PPCF128] = ISD::SETLE;
517   CCs[RTLIB::OGT_F32] = ISD::SETGT;
518   CCs[RTLIB::OGT_F64] = ISD::SETGT;
519   CCs[RTLIB::OGT_F128] = ISD::SETGT;
520   CCs[RTLIB::OGT_PPCF128] = ISD::SETGT;
521   CCs[RTLIB::UO_F32] = ISD::SETNE;
522   CCs[RTLIB::UO_F64] = ISD::SETNE;
523   CCs[RTLIB::UO_F128] = ISD::SETNE;
524   CCs[RTLIB::UO_PPCF128] = ISD::SETNE;
525   CCs[RTLIB::O_F32] = ISD::SETEQ;
526   CCs[RTLIB::O_F64] = ISD::SETEQ;
527   CCs[RTLIB::O_F128] = ISD::SETEQ;
528   CCs[RTLIB::O_PPCF128] = ISD::SETEQ;
529 }
530 
531 /// NOTE: The TargetMachine owns TLOF.
532 TargetLoweringBase::TargetLoweringBase(const TargetMachine &tm) : TM(tm) {
533   initActions();
534 
535   // Perform these initializations only once.
536   MaxStoresPerMemset = MaxStoresPerMemcpy = MaxStoresPerMemmove =
537       MaxLoadsPerMemcmp = 8;
538   MaxGluedStoresPerMemcpy = 0;
539   MaxStoresPerMemsetOptSize = MaxStoresPerMemcpyOptSize =
540       MaxStoresPerMemmoveOptSize = MaxLoadsPerMemcmpOptSize = 4;
541   UseUnderscoreSetJmp = false;
542   UseUnderscoreLongJmp = false;
543   HasMultipleConditionRegisters = false;
544   HasExtractBitsInsn = false;
545   JumpIsExpensive = JumpIsExpensiveOverride;
546   PredictableSelectIsExpensive = false;
547   EnableExtLdPromotion = false;
548   StackPointerRegisterToSaveRestore = 0;
549   BooleanContents = UndefinedBooleanContent;
550   BooleanFloatContents = UndefinedBooleanContent;
551   BooleanVectorContents = UndefinedBooleanContent;
552   SchedPreferenceInfo = Sched::ILP;
553   JumpBufSize = 0;
554   JumpBufAlignment = 0;
555   MinFunctionAlignment = 0;
556   PrefFunctionAlignment = 0;
557   PrefLoopAlignment = 0;
558   GatherAllAliasesMaxDepth = 18;
559   MinStackArgumentAlignment = 1;
560   // TODO: the default will be switched to 0 in the next commit, along
561   // with the Target-specific changes necessary.
562   MaxAtomicSizeInBitsSupported = 1024;
563 
564   MinCmpXchgSizeInBits = 0;
565   SupportsUnalignedAtomics = false;
566 
567   std::fill(std::begin(LibcallRoutineNames), std::end(LibcallRoutineNames), nullptr);
568 
569   InitLibcalls(TM.getTargetTriple());
570   InitCmpLibcallCCs(CmpLibcallCCs);
571 }
572 
573 void TargetLoweringBase::initActions() {
574   // All operations default to being supported.
575   memset(OpActions, 0, sizeof(OpActions));
576   memset(LoadExtActions, 0, sizeof(LoadExtActions));
577   memset(TruncStoreActions, 0, sizeof(TruncStoreActions));
578   memset(IndexedModeActions, 0, sizeof(IndexedModeActions));
579   memset(CondCodeActions, 0, sizeof(CondCodeActions));
580   std::fill(std::begin(RegClassForVT), std::end(RegClassForVT), nullptr);
581   std::fill(std::begin(TargetDAGCombineArray),
582             std::end(TargetDAGCombineArray), 0);
583 
584   for (MVT VT : MVT::fp_valuetypes()) {
585     MVT IntVT = MVT::getIntegerVT(VT.getSizeInBits());
586     if (IntVT.isValid()) {
587       setOperationAction(ISD::ATOMIC_SWAP, VT, Promote);
588       AddPromotedToType(ISD::ATOMIC_SWAP, VT, IntVT);
589     }
590   }
591 
592   // Set default actions for various operations.
593   for (MVT VT : MVT::all_valuetypes()) {
594     // Default all indexed load / store to expand.
595     for (unsigned IM = (unsigned)ISD::PRE_INC;
596          IM != (unsigned)ISD::LAST_INDEXED_MODE; ++IM) {
597       setIndexedLoadAction(IM, VT, Expand);
598       setIndexedStoreAction(IM, VT, Expand);
599     }
600 
601     // Most backends expect to see the node which just returns the value loaded.
602     setOperationAction(ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS, VT, Expand);
603 
604     // These operations default to expand.
605     setOperationAction(ISD::FGETSIGN, VT, Expand);
606     setOperationAction(ISD::CONCAT_VECTORS, VT, Expand);
607     setOperationAction(ISD::FMINNUM, VT, Expand);
608     setOperationAction(ISD::FMAXNUM, VT, Expand);
609     setOperationAction(ISD::FMINNUM_IEEE, VT, Expand);
610     setOperationAction(ISD::FMAXNUM_IEEE, VT, Expand);
611     setOperationAction(ISD::FMINIMUM, VT, Expand);
612     setOperationAction(ISD::FMAXIMUM, VT, Expand);
613     setOperationAction(ISD::FMAD, VT, Expand);
614     setOperationAction(ISD::SMIN, VT, Expand);
615     setOperationAction(ISD::SMAX, VT, Expand);
616     setOperationAction(ISD::UMIN, VT, Expand);
617     setOperationAction(ISD::UMAX, VT, Expand);
618     setOperationAction(ISD::ABS, VT, Expand);
619     setOperationAction(ISD::FSHL, VT, Expand);
620     setOperationAction(ISD::FSHR, VT, Expand);
621     setOperationAction(ISD::SADDSAT, VT, Expand);
622     setOperationAction(ISD::UADDSAT, VT, Expand);
623     setOperationAction(ISD::SSUBSAT, VT, Expand);
624     setOperationAction(ISD::USUBSAT, VT, Expand);
625     setOperationAction(ISD::SMULFIX, VT, Expand);
626     setOperationAction(ISD::SMULFIXSAT, VT, Expand);
627     setOperationAction(ISD::UMULFIX, VT, Expand);
628 
629     // Overflow operations default to expand
630     setOperationAction(ISD::SADDO, VT, Expand);
631     setOperationAction(ISD::SSUBO, VT, Expand);
632     setOperationAction(ISD::UADDO, VT, Expand);
633     setOperationAction(ISD::USUBO, VT, Expand);
634     setOperationAction(ISD::SMULO, VT, Expand);
635     setOperationAction(ISD::UMULO, VT, Expand);
636 
637     // ADDCARRY operations default to expand
638     setOperationAction(ISD::ADDCARRY, VT, Expand);
639     setOperationAction(ISD::SUBCARRY, VT, Expand);
640     setOperationAction(ISD::SETCCCARRY, VT, Expand);
641 
642     // ADDC/ADDE/SUBC/SUBE default to expand.
643     setOperationAction(ISD::ADDC, VT, Expand);
644     setOperationAction(ISD::ADDE, VT, Expand);
645     setOperationAction(ISD::SUBC, VT, Expand);
646     setOperationAction(ISD::SUBE, VT, Expand);
647 
648     // These default to Expand so they will be expanded to CTLZ/CTTZ by default.
649     setOperationAction(ISD::CTLZ_ZERO_UNDEF, VT, Expand);
650     setOperationAction(ISD::CTTZ_ZERO_UNDEF, VT, Expand);
651 
652     setOperationAction(ISD::BITREVERSE, VT, Expand);
653 
654     // These library functions default to expand.
655     setOperationAction(ISD::FROUND, VT, Expand);
656     setOperationAction(ISD::FPOWI, VT, Expand);
657 
658     // These operations default to expand for vector types.
659     if (VT.isVector()) {
660       setOperationAction(ISD::FCOPYSIGN, VT, Expand);
661       setOperationAction(ISD::ANY_EXTEND_VECTOR_INREG, VT, Expand);
662       setOperationAction(ISD::SIGN_EXTEND_VECTOR_INREG, VT, Expand);
663       setOperationAction(ISD::ZERO_EXTEND_VECTOR_INREG, VT, Expand);
664     }
665 
666     // For most targets @llvm.get.dynamic.area.offset just returns 0.
667     setOperationAction(ISD::GET_DYNAMIC_AREA_OFFSET, VT, Expand);
668 
669     // Vector reduction default to expand.
670     setOperationAction(ISD::VECREDUCE_FADD, VT, Expand);
671     setOperationAction(ISD::VECREDUCE_FMUL, VT, Expand);
672     setOperationAction(ISD::VECREDUCE_ADD, VT, Expand);
673     setOperationAction(ISD::VECREDUCE_MUL, VT, Expand);
674     setOperationAction(ISD::VECREDUCE_AND, VT, Expand);
675     setOperationAction(ISD::VECREDUCE_OR, VT, Expand);
676     setOperationAction(ISD::VECREDUCE_XOR, VT, Expand);
677     setOperationAction(ISD::VECREDUCE_SMAX, VT, Expand);
678     setOperationAction(ISD::VECREDUCE_SMIN, VT, Expand);
679     setOperationAction(ISD::VECREDUCE_UMAX, VT, Expand);
680     setOperationAction(ISD::VECREDUCE_UMIN, VT, Expand);
681     setOperationAction(ISD::VECREDUCE_FMAX, VT, Expand);
682     setOperationAction(ISD::VECREDUCE_FMIN, VT, Expand);
683   }
684 
685   // Most targets ignore the @llvm.prefetch intrinsic.
686   setOperationAction(ISD::PREFETCH, MVT::Other, Expand);
687 
688   // Most targets also ignore the @llvm.readcyclecounter intrinsic.
689   setOperationAction(ISD::READCYCLECOUNTER, MVT::i64, Expand);
690 
691   // ConstantFP nodes default to expand.  Targets can either change this to
692   // Legal, in which case all fp constants are legal, or use isFPImmLegal()
693   // to optimize expansions for certain constants.
694   setOperationAction(ISD::ConstantFP, MVT::f16, Expand);
695   setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
696   setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
697   setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
698   setOperationAction(ISD::ConstantFP, MVT::f128, Expand);
699 
700   // These library functions default to expand.
701   for (MVT VT : {MVT::f32, MVT::f64, MVT::f128}) {
702     setOperationAction(ISD::FCBRT,      VT, Expand);
703     setOperationAction(ISD::FLOG ,      VT, Expand);
704     setOperationAction(ISD::FLOG2,      VT, Expand);
705     setOperationAction(ISD::FLOG10,     VT, Expand);
706     setOperationAction(ISD::FEXP ,      VT, Expand);
707     setOperationAction(ISD::FEXP2,      VT, Expand);
708     setOperationAction(ISD::FFLOOR,     VT, Expand);
709     setOperationAction(ISD::FNEARBYINT, VT, Expand);
710     setOperationAction(ISD::FCEIL,      VT, Expand);
711     setOperationAction(ISD::FRINT,      VT, Expand);
712     setOperationAction(ISD::FTRUNC,     VT, Expand);
713     setOperationAction(ISD::FROUND,     VT, Expand);
714     setOperationAction(ISD::LROUND,     VT, Expand);
715     setOperationAction(ISD::LLROUND,    VT, Expand);
716   }
717 
718   // Default ISD::TRAP to expand (which turns it into abort).
719   setOperationAction(ISD::TRAP, MVT::Other, Expand);
720 
721   // On most systems, DEBUGTRAP and TRAP have no difference. The "Expand"
722   // here is to inform DAG Legalizer to replace DEBUGTRAP with TRAP.
723   setOperationAction(ISD::DEBUGTRAP, MVT::Other, Expand);
724 }
725 
726 MVT TargetLoweringBase::getScalarShiftAmountTy(const DataLayout &DL,
727                                                EVT) const {
728   return MVT::getIntegerVT(DL.getPointerSizeInBits(0));
729 }
730 
731 EVT TargetLoweringBase::getShiftAmountTy(EVT LHSTy, const DataLayout &DL,
732                                          bool LegalTypes) const {
733   assert(LHSTy.isInteger() && "Shift amount is not an integer type!");
734   if (LHSTy.isVector())
735     return LHSTy;
736   return LegalTypes ? getScalarShiftAmountTy(DL, LHSTy)
737                     : getPointerTy(DL);
738 }
739 
740 bool TargetLoweringBase::canOpTrap(unsigned Op, EVT VT) const {
741   assert(isTypeLegal(VT));
742   switch (Op) {
743   default:
744     return false;
745   case ISD::SDIV:
746   case ISD::UDIV:
747   case ISD::SREM:
748   case ISD::UREM:
749     return true;
750   }
751 }
752 
753 void TargetLoweringBase::setJumpIsExpensive(bool isExpensive) {
754   // If the command-line option was specified, ignore this request.
755   if (!JumpIsExpensiveOverride.getNumOccurrences())
756     JumpIsExpensive = isExpensive;
757 }
758 
759 TargetLoweringBase::LegalizeKind
760 TargetLoweringBase::getTypeConversion(LLVMContext &Context, EVT VT) const {
761   // If this is a simple type, use the ComputeRegisterProp mechanism.
762   if (VT.isSimple()) {
763     MVT SVT = VT.getSimpleVT();
764     assert((unsigned)SVT.SimpleTy < array_lengthof(TransformToType));
765     MVT NVT = TransformToType[SVT.SimpleTy];
766     LegalizeTypeAction LA = ValueTypeActions.getTypeAction(SVT);
767 
768     assert((LA == TypeLegal || LA == TypeSoftenFloat ||
769             ValueTypeActions.getTypeAction(NVT) != TypePromoteInteger) &&
770            "Promote may not follow Expand or Promote");
771 
772     if (LA == TypeSplitVector)
773       return LegalizeKind(LA,
774                           EVT::getVectorVT(Context, SVT.getVectorElementType(),
775                                            SVT.getVectorNumElements() / 2));
776     if (LA == TypeScalarizeVector)
777       return LegalizeKind(LA, SVT.getVectorElementType());
778     return LegalizeKind(LA, NVT);
779   }
780 
781   // Handle Extended Scalar Types.
782   if (!VT.isVector()) {
783     assert(VT.isInteger() && "Float types must be simple");
784     unsigned BitSize = VT.getSizeInBits();
785     // First promote to a power-of-two size, then expand if necessary.
786     if (BitSize < 8 || !isPowerOf2_32(BitSize)) {
787       EVT NVT = VT.getRoundIntegerType(Context);
788       assert(NVT != VT && "Unable to round integer VT");
789       LegalizeKind NextStep = getTypeConversion(Context, NVT);
790       // Avoid multi-step promotion.
791       if (NextStep.first == TypePromoteInteger)
792         return NextStep;
793       // Return rounded integer type.
794       return LegalizeKind(TypePromoteInteger, NVT);
795     }
796 
797     return LegalizeKind(TypeExpandInteger,
798                         EVT::getIntegerVT(Context, VT.getSizeInBits() / 2));
799   }
800 
801   // Handle vector types.
802   unsigned NumElts = VT.getVectorNumElements();
803   EVT EltVT = VT.getVectorElementType();
804 
805   // Vectors with only one element are always scalarized.
806   if (NumElts == 1)
807     return LegalizeKind(TypeScalarizeVector, EltVT);
808 
809   // Try to widen vector elements until the element type is a power of two and
810   // promote it to a legal type later on, for example:
811   // <3 x i8> -> <4 x i8> -> <4 x i32>
812   if (EltVT.isInteger()) {
813     // Vectors with a number of elements that is not a power of two are always
814     // widened, for example <3 x i8> -> <4 x i8>.
815     if (!VT.isPow2VectorType()) {
816       NumElts = (unsigned)NextPowerOf2(NumElts);
817       EVT NVT = EVT::getVectorVT(Context, EltVT, NumElts);
818       return LegalizeKind(TypeWidenVector, NVT);
819     }
820 
821     // Examine the element type.
822     LegalizeKind LK = getTypeConversion(Context, EltVT);
823 
824     // If type is to be expanded, split the vector.
825     //  <4 x i140> -> <2 x i140>
826     if (LK.first == TypeExpandInteger)
827       return LegalizeKind(TypeSplitVector,
828                           EVT::getVectorVT(Context, EltVT, NumElts / 2));
829 
830     // Promote the integer element types until a legal vector type is found
831     // or until the element integer type is too big. If a legal type was not
832     // found, fallback to the usual mechanism of widening/splitting the
833     // vector.
834     EVT OldEltVT = EltVT;
835     while (true) {
836       // Increase the bitwidth of the element to the next pow-of-two
837       // (which is greater than 8 bits).
838       EltVT = EVT::getIntegerVT(Context, 1 + EltVT.getSizeInBits())
839                   .getRoundIntegerType(Context);
840 
841       // Stop trying when getting a non-simple element type.
842       // Note that vector elements may be greater than legal vector element
843       // types. Example: X86 XMM registers hold 64bit element on 32bit
844       // systems.
845       if (!EltVT.isSimple())
846         break;
847 
848       // Build a new vector type and check if it is legal.
849       MVT NVT = MVT::getVectorVT(EltVT.getSimpleVT(), NumElts);
850       // Found a legal promoted vector type.
851       if (NVT != MVT() && ValueTypeActions.getTypeAction(NVT) == TypeLegal)
852         return LegalizeKind(TypePromoteInteger,
853                             EVT::getVectorVT(Context, EltVT, NumElts));
854     }
855 
856     // Reset the type to the unexpanded type if we did not find a legal vector
857     // type with a promoted vector element type.
858     EltVT = OldEltVT;
859   }
860 
861   // Try to widen the vector until a legal type is found.
862   // If there is no wider legal type, split the vector.
863   while (true) {
864     // Round up to the next power of 2.
865     NumElts = (unsigned)NextPowerOf2(NumElts);
866 
867     // If there is no simple vector type with this many elements then there
868     // cannot be a larger legal vector type.  Note that this assumes that
869     // there are no skipped intermediate vector types in the simple types.
870     if (!EltVT.isSimple())
871       break;
872     MVT LargerVector = MVT::getVectorVT(EltVT.getSimpleVT(), NumElts);
873     if (LargerVector == MVT())
874       break;
875 
876     // If this type is legal then widen the vector.
877     if (ValueTypeActions.getTypeAction(LargerVector) == TypeLegal)
878       return LegalizeKind(TypeWidenVector, LargerVector);
879   }
880 
881   // Widen odd vectors to next power of two.
882   if (!VT.isPow2VectorType()) {
883     EVT NVT = VT.getPow2VectorType(Context);
884     return LegalizeKind(TypeWidenVector, NVT);
885   }
886 
887   // Vectors with illegal element types are expanded.
888   EVT NVT = EVT::getVectorVT(Context, EltVT, VT.getVectorNumElements() / 2);
889   return LegalizeKind(TypeSplitVector, NVT);
890 }
891 
892 static unsigned getVectorTypeBreakdownMVT(MVT VT, MVT &IntermediateVT,
893                                           unsigned &NumIntermediates,
894                                           MVT &RegisterVT,
895                                           TargetLoweringBase *TLI) {
896   // Figure out the right, legal destination reg to copy into.
897   unsigned NumElts = VT.getVectorNumElements();
898   MVT EltTy = VT.getVectorElementType();
899 
900   unsigned NumVectorRegs = 1;
901 
902   // FIXME: We don't support non-power-of-2-sized vectors for now.  Ideally we
903   // could break down into LHS/RHS like LegalizeDAG does.
904   if (!isPowerOf2_32(NumElts)) {
905     NumVectorRegs = NumElts;
906     NumElts = 1;
907   }
908 
909   // Divide the input until we get to a supported size.  This will always
910   // end with a scalar if the target doesn't support vectors.
911   while (NumElts > 1 && !TLI->isTypeLegal(MVT::getVectorVT(EltTy, NumElts))) {
912     NumElts >>= 1;
913     NumVectorRegs <<= 1;
914   }
915 
916   NumIntermediates = NumVectorRegs;
917 
918   MVT NewVT = MVT::getVectorVT(EltTy, NumElts);
919   if (!TLI->isTypeLegal(NewVT))
920     NewVT = EltTy;
921   IntermediateVT = NewVT;
922 
923   unsigned NewVTSize = NewVT.getSizeInBits();
924 
925   // Convert sizes such as i33 to i64.
926   if (!isPowerOf2_32(NewVTSize))
927     NewVTSize = NextPowerOf2(NewVTSize);
928 
929   MVT DestVT = TLI->getRegisterType(NewVT);
930   RegisterVT = DestVT;
931   if (EVT(DestVT).bitsLT(NewVT))    // Value is expanded, e.g. i64 -> i16.
932     return NumVectorRegs*(NewVTSize/DestVT.getSizeInBits());
933 
934   // Otherwise, promotion or legal types use the same number of registers as
935   // the vector decimated to the appropriate level.
936   return NumVectorRegs;
937 }
938 
939 /// isLegalRC - Return true if the value types that can be represented by the
940 /// specified register class are all legal.
941 bool TargetLoweringBase::isLegalRC(const TargetRegisterInfo &TRI,
942                                    const TargetRegisterClass &RC) const {
943   for (auto I = TRI.legalclasstypes_begin(RC); *I != MVT::Other; ++I)
944     if (isTypeLegal(*I))
945       return true;
946   return false;
947 }
948 
949 /// Replace/modify any TargetFrameIndex operands with a targte-dependent
950 /// sequence of memory operands that is recognized by PrologEpilogInserter.
951 MachineBasicBlock *
952 TargetLoweringBase::emitPatchPoint(MachineInstr &InitialMI,
953                                    MachineBasicBlock *MBB) const {
954   MachineInstr *MI = &InitialMI;
955   MachineFunction &MF = *MI->getMF();
956   MachineFrameInfo &MFI = MF.getFrameInfo();
957 
958   // We're handling multiple types of operands here:
959   // PATCHPOINT MetaArgs - live-in, read only, direct
960   // STATEPOINT Deopt Spill - live-through, read only, indirect
961   // STATEPOINT Deopt Alloca - live-through, read only, direct
962   // (We're currently conservative and mark the deopt slots read/write in
963   // practice.)
964   // STATEPOINT GC Spill - live-through, read/write, indirect
965   // STATEPOINT GC Alloca - live-through, read/write, direct
966   // The live-in vs live-through is handled already (the live through ones are
967   // all stack slots), but we need to handle the different type of stackmap
968   // operands and memory effects here.
969 
970   // MI changes inside this loop as we grow operands.
971   for(unsigned OperIdx = 0; OperIdx != MI->getNumOperands(); ++OperIdx) {
972     MachineOperand &MO = MI->getOperand(OperIdx);
973     if (!MO.isFI())
974       continue;
975 
976     // foldMemoryOperand builds a new MI after replacing a single FI operand
977     // with the canonical set of five x86 addressing-mode operands.
978     int FI = MO.getIndex();
979     MachineInstrBuilder MIB = BuildMI(MF, MI->getDebugLoc(), MI->getDesc());
980 
981     // Copy operands before the frame-index.
982     for (unsigned i = 0; i < OperIdx; ++i)
983       MIB.add(MI->getOperand(i));
984     // Add frame index operands recognized by stackmaps.cpp
985     if (MFI.isStatepointSpillSlotObjectIndex(FI)) {
986       // indirect-mem-ref tag, size, #FI, offset.
987       // Used for spills inserted by StatepointLowering.  This codepath is not
988       // used for patchpoints/stackmaps at all, for these spilling is done via
989       // foldMemoryOperand callback only.
990       assert(MI->getOpcode() == TargetOpcode::STATEPOINT && "sanity");
991       MIB.addImm(StackMaps::IndirectMemRefOp);
992       MIB.addImm(MFI.getObjectSize(FI));
993       MIB.add(MI->getOperand(OperIdx));
994       MIB.addImm(0);
995     } else {
996       // direct-mem-ref tag, #FI, offset.
997       // Used by patchpoint, and direct alloca arguments to statepoints
998       MIB.addImm(StackMaps::DirectMemRefOp);
999       MIB.add(MI->getOperand(OperIdx));
1000       MIB.addImm(0);
1001     }
1002     // Copy the operands after the frame index.
1003     for (unsigned i = OperIdx + 1; i != MI->getNumOperands(); ++i)
1004       MIB.add(MI->getOperand(i));
1005 
1006     // Inherit previous memory operands.
1007     MIB.cloneMemRefs(*MI);
1008     assert(MIB->mayLoad() && "Folded a stackmap use to a non-load!");
1009 
1010     // Add a new memory operand for this FI.
1011     assert(MFI.getObjectOffset(FI) != -1);
1012 
1013     // Note: STATEPOINT MMOs are added during SelectionDAG.  STACKMAP, and
1014     // PATCHPOINT should be updated to do the same. (TODO)
1015     if (MI->getOpcode() != TargetOpcode::STATEPOINT) {
1016       auto Flags = MachineMemOperand::MOLoad;
1017       MachineMemOperand *MMO = MF.getMachineMemOperand(
1018           MachinePointerInfo::getFixedStack(MF, FI), Flags,
1019           MF.getDataLayout().getPointerSize(), MFI.getObjectAlignment(FI));
1020       MIB->addMemOperand(MF, MMO);
1021     }
1022 
1023     // Replace the instruction and update the operand index.
1024     MBB->insert(MachineBasicBlock::iterator(MI), MIB);
1025     OperIdx += (MIB->getNumOperands() - MI->getNumOperands()) - 1;
1026     MI->eraseFromParent();
1027     MI = MIB;
1028   }
1029   return MBB;
1030 }
1031 
1032 MachineBasicBlock *
1033 TargetLoweringBase::emitXRayCustomEvent(MachineInstr &MI,
1034                                         MachineBasicBlock *MBB) const {
1035   assert(MI.getOpcode() == TargetOpcode::PATCHABLE_EVENT_CALL &&
1036          "Called emitXRayCustomEvent on the wrong MI!");
1037   auto &MF = *MI.getMF();
1038   auto MIB = BuildMI(MF, MI.getDebugLoc(), MI.getDesc());
1039   for (unsigned OpIdx = 0; OpIdx != MI.getNumOperands(); ++OpIdx)
1040     MIB.add(MI.getOperand(OpIdx));
1041 
1042   MBB->insert(MachineBasicBlock::iterator(MI), MIB);
1043   MI.eraseFromParent();
1044   return MBB;
1045 }
1046 
1047 MachineBasicBlock *
1048 TargetLoweringBase::emitXRayTypedEvent(MachineInstr &MI,
1049                                        MachineBasicBlock *MBB) const {
1050   assert(MI.getOpcode() == TargetOpcode::PATCHABLE_TYPED_EVENT_CALL &&
1051          "Called emitXRayTypedEvent on the wrong MI!");
1052   auto &MF = *MI.getMF();
1053   auto MIB = BuildMI(MF, MI.getDebugLoc(), MI.getDesc());
1054   for (unsigned OpIdx = 0; OpIdx != MI.getNumOperands(); ++OpIdx)
1055     MIB.add(MI.getOperand(OpIdx));
1056 
1057   MBB->insert(MachineBasicBlock::iterator(MI), MIB);
1058   MI.eraseFromParent();
1059   return MBB;
1060 }
1061 
1062 /// findRepresentativeClass - Return the largest legal super-reg register class
1063 /// of the register class for the specified type and its associated "cost".
1064 // This function is in TargetLowering because it uses RegClassForVT which would
1065 // need to be moved to TargetRegisterInfo and would necessitate moving
1066 // isTypeLegal over as well - a massive change that would just require
1067 // TargetLowering having a TargetRegisterInfo class member that it would use.
1068 std::pair<const TargetRegisterClass *, uint8_t>
1069 TargetLoweringBase::findRepresentativeClass(const TargetRegisterInfo *TRI,
1070                                             MVT VT) const {
1071   const TargetRegisterClass *RC = RegClassForVT[VT.SimpleTy];
1072   if (!RC)
1073     return std::make_pair(RC, 0);
1074 
1075   // Compute the set of all super-register classes.
1076   BitVector SuperRegRC(TRI->getNumRegClasses());
1077   for (SuperRegClassIterator RCI(RC, TRI); RCI.isValid(); ++RCI)
1078     SuperRegRC.setBitsInMask(RCI.getMask());
1079 
1080   // Find the first legal register class with the largest spill size.
1081   const TargetRegisterClass *BestRC = RC;
1082   for (unsigned i : SuperRegRC.set_bits()) {
1083     const TargetRegisterClass *SuperRC = TRI->getRegClass(i);
1084     // We want the largest possible spill size.
1085     if (TRI->getSpillSize(*SuperRC) <= TRI->getSpillSize(*BestRC))
1086       continue;
1087     if (!isLegalRC(*TRI, *SuperRC))
1088       continue;
1089     BestRC = SuperRC;
1090   }
1091   return std::make_pair(BestRC, 1);
1092 }
1093 
1094 /// computeRegisterProperties - Once all of the register classes are added,
1095 /// this allows us to compute derived properties we expose.
1096 void TargetLoweringBase::computeRegisterProperties(
1097     const TargetRegisterInfo *TRI) {
1098   static_assert(MVT::LAST_VALUETYPE <= MVT::MAX_ALLOWED_VALUETYPE,
1099                 "Too many value types for ValueTypeActions to hold!");
1100 
1101   // Everything defaults to needing one register.
1102   for (unsigned i = 0; i != MVT::LAST_VALUETYPE; ++i) {
1103     NumRegistersForVT[i] = 1;
1104     RegisterTypeForVT[i] = TransformToType[i] = (MVT::SimpleValueType)i;
1105   }
1106   // ...except isVoid, which doesn't need any registers.
1107   NumRegistersForVT[MVT::isVoid] = 0;
1108 
1109   // Find the largest integer register class.
1110   unsigned LargestIntReg = MVT::LAST_INTEGER_VALUETYPE;
1111   for (; RegClassForVT[LargestIntReg] == nullptr; --LargestIntReg)
1112     assert(LargestIntReg != MVT::i1 && "No integer registers defined!");
1113 
1114   // Every integer value type larger than this largest register takes twice as
1115   // many registers to represent as the previous ValueType.
1116   for (unsigned ExpandedReg = LargestIntReg + 1;
1117        ExpandedReg <= MVT::LAST_INTEGER_VALUETYPE; ++ExpandedReg) {
1118     NumRegistersForVT[ExpandedReg] = 2*NumRegistersForVT[ExpandedReg-1];
1119     RegisterTypeForVT[ExpandedReg] = (MVT::SimpleValueType)LargestIntReg;
1120     TransformToType[ExpandedReg] = (MVT::SimpleValueType)(ExpandedReg - 1);
1121     ValueTypeActions.setTypeAction((MVT::SimpleValueType)ExpandedReg,
1122                                    TypeExpandInteger);
1123   }
1124 
1125   // Inspect all of the ValueType's smaller than the largest integer
1126   // register to see which ones need promotion.
1127   unsigned LegalIntReg = LargestIntReg;
1128   for (unsigned IntReg = LargestIntReg - 1;
1129        IntReg >= (unsigned)MVT::i1; --IntReg) {
1130     MVT IVT = (MVT::SimpleValueType)IntReg;
1131     if (isTypeLegal(IVT)) {
1132       LegalIntReg = IntReg;
1133     } else {
1134       RegisterTypeForVT[IntReg] = TransformToType[IntReg] =
1135         (MVT::SimpleValueType)LegalIntReg;
1136       ValueTypeActions.setTypeAction(IVT, TypePromoteInteger);
1137     }
1138   }
1139 
1140   // ppcf128 type is really two f64's.
1141   if (!isTypeLegal(MVT::ppcf128)) {
1142     if (isTypeLegal(MVT::f64)) {
1143       NumRegistersForVT[MVT::ppcf128] = 2*NumRegistersForVT[MVT::f64];
1144       RegisterTypeForVT[MVT::ppcf128] = MVT::f64;
1145       TransformToType[MVT::ppcf128] = MVT::f64;
1146       ValueTypeActions.setTypeAction(MVT::ppcf128, TypeExpandFloat);
1147     } else {
1148       NumRegistersForVT[MVT::ppcf128] = NumRegistersForVT[MVT::i128];
1149       RegisterTypeForVT[MVT::ppcf128] = RegisterTypeForVT[MVT::i128];
1150       TransformToType[MVT::ppcf128] = MVT::i128;
1151       ValueTypeActions.setTypeAction(MVT::ppcf128, TypeSoftenFloat);
1152     }
1153   }
1154 
1155   // Decide how to handle f128. If the target does not have native f128 support,
1156   // expand it to i128 and we will be generating soft float library calls.
1157   if (!isTypeLegal(MVT::f128)) {
1158     NumRegistersForVT[MVT::f128] = NumRegistersForVT[MVT::i128];
1159     RegisterTypeForVT[MVT::f128] = RegisterTypeForVT[MVT::i128];
1160     TransformToType[MVT::f128] = MVT::i128;
1161     ValueTypeActions.setTypeAction(MVT::f128, TypeSoftenFloat);
1162   }
1163 
1164   // Decide how to handle f64. If the target does not have native f64 support,
1165   // expand it to i64 and we will be generating soft float library calls.
1166   if (!isTypeLegal(MVT::f64)) {
1167     NumRegistersForVT[MVT::f64] = NumRegistersForVT[MVT::i64];
1168     RegisterTypeForVT[MVT::f64] = RegisterTypeForVT[MVT::i64];
1169     TransformToType[MVT::f64] = MVT::i64;
1170     ValueTypeActions.setTypeAction(MVT::f64, TypeSoftenFloat);
1171   }
1172 
1173   // Decide how to handle f32. If the target does not have native f32 support,
1174   // expand it to i32 and we will be generating soft float library calls.
1175   if (!isTypeLegal(MVT::f32)) {
1176     NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::i32];
1177     RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::i32];
1178     TransformToType[MVT::f32] = MVT::i32;
1179     ValueTypeActions.setTypeAction(MVT::f32, TypeSoftenFloat);
1180   }
1181 
1182   // Decide how to handle f16. If the target does not have native f16 support,
1183   // promote it to f32, because there are no f16 library calls (except for
1184   // conversions).
1185   if (!isTypeLegal(MVT::f16)) {
1186     NumRegistersForVT[MVT::f16] = NumRegistersForVT[MVT::f32];
1187     RegisterTypeForVT[MVT::f16] = RegisterTypeForVT[MVT::f32];
1188     TransformToType[MVT::f16] = MVT::f32;
1189     ValueTypeActions.setTypeAction(MVT::f16, TypePromoteFloat);
1190   }
1191 
1192   // Loop over all of the vector value types to see which need transformations.
1193   for (unsigned i = MVT::FIRST_VECTOR_VALUETYPE;
1194        i <= (unsigned)MVT::LAST_VECTOR_VALUETYPE; ++i) {
1195     MVT VT = (MVT::SimpleValueType) i;
1196     if (isTypeLegal(VT))
1197       continue;
1198 
1199     MVT EltVT = VT.getVectorElementType();
1200     unsigned NElts = VT.getVectorNumElements();
1201     bool IsLegalWiderType = false;
1202     LegalizeTypeAction PreferredAction = getPreferredVectorAction(VT);
1203     switch (PreferredAction) {
1204     case TypePromoteInteger:
1205       // Try to promote the elements of integer vectors. If no legal
1206       // promotion was found, fall through to the widen-vector method.
1207       for (unsigned nVT = i + 1; nVT <= MVT::LAST_INTEGER_VECTOR_VALUETYPE; ++nVT) {
1208         MVT SVT = (MVT::SimpleValueType) nVT;
1209         // Promote vectors of integers to vectors with the same number
1210         // of elements, with a wider element type.
1211         if (SVT.getScalarSizeInBits() > EltVT.getSizeInBits() &&
1212             SVT.getVectorNumElements() == NElts && isTypeLegal(SVT)) {
1213           TransformToType[i] = SVT;
1214           RegisterTypeForVT[i] = SVT;
1215           NumRegistersForVT[i] = 1;
1216           ValueTypeActions.setTypeAction(VT, TypePromoteInteger);
1217           IsLegalWiderType = true;
1218           break;
1219         }
1220       }
1221       if (IsLegalWiderType)
1222         break;
1223       LLVM_FALLTHROUGH;
1224 
1225     case TypeWidenVector:
1226       // Try to widen the vector.
1227       for (unsigned nVT = i + 1; nVT <= MVT::LAST_VECTOR_VALUETYPE; ++nVT) {
1228         MVT SVT = (MVT::SimpleValueType) nVT;
1229         if (SVT.getVectorElementType() == EltVT
1230             && SVT.getVectorNumElements() > NElts && isTypeLegal(SVT)) {
1231           TransformToType[i] = SVT;
1232           RegisterTypeForVT[i] = SVT;
1233           NumRegistersForVT[i] = 1;
1234           ValueTypeActions.setTypeAction(VT, TypeWidenVector);
1235           IsLegalWiderType = true;
1236           break;
1237         }
1238       }
1239       if (IsLegalWiderType)
1240         break;
1241       LLVM_FALLTHROUGH;
1242 
1243     case TypeSplitVector:
1244     case TypeScalarizeVector: {
1245       MVT IntermediateVT;
1246       MVT RegisterVT;
1247       unsigned NumIntermediates;
1248       NumRegistersForVT[i] = getVectorTypeBreakdownMVT(VT, IntermediateVT,
1249           NumIntermediates, RegisterVT, this);
1250       RegisterTypeForVT[i] = RegisterVT;
1251 
1252       MVT NVT = VT.getPow2VectorType();
1253       if (NVT == VT) {
1254         // Type is already a power of 2.  The default action is to split.
1255         TransformToType[i] = MVT::Other;
1256         if (PreferredAction == TypeScalarizeVector)
1257           ValueTypeActions.setTypeAction(VT, TypeScalarizeVector);
1258         else if (PreferredAction == TypeSplitVector)
1259           ValueTypeActions.setTypeAction(VT, TypeSplitVector);
1260         else
1261           // Set type action according to the number of elements.
1262           ValueTypeActions.setTypeAction(VT, NElts == 1 ? TypeScalarizeVector
1263                                                         : TypeSplitVector);
1264       } else {
1265         TransformToType[i] = NVT;
1266         ValueTypeActions.setTypeAction(VT, TypeWidenVector);
1267       }
1268       break;
1269     }
1270     default:
1271       llvm_unreachable("Unknown vector legalization action!");
1272     }
1273   }
1274 
1275   // Determine the 'representative' register class for each value type.
1276   // An representative register class is the largest (meaning one which is
1277   // not a sub-register class / subreg register class) legal register class for
1278   // a group of value types. For example, on i386, i8, i16, and i32
1279   // representative would be GR32; while on x86_64 it's GR64.
1280   for (unsigned i = 0; i != MVT::LAST_VALUETYPE; ++i) {
1281     const TargetRegisterClass* RRC;
1282     uint8_t Cost;
1283     std::tie(RRC, Cost) = findRepresentativeClass(TRI, (MVT::SimpleValueType)i);
1284     RepRegClassForVT[i] = RRC;
1285     RepRegClassCostForVT[i] = Cost;
1286   }
1287 }
1288 
1289 EVT TargetLoweringBase::getSetCCResultType(const DataLayout &DL, LLVMContext &,
1290                                            EVT VT) const {
1291   assert(!VT.isVector() && "No default SetCC type for vectors!");
1292   return getPointerTy(DL).SimpleTy;
1293 }
1294 
1295 MVT::SimpleValueType TargetLoweringBase::getCmpLibcallReturnType() const {
1296   return MVT::i32; // return the default value
1297 }
1298 
1299 /// getVectorTypeBreakdown - Vector types are broken down into some number of
1300 /// legal first class types.  For example, MVT::v8f32 maps to 2 MVT::v4f32
1301 /// with Altivec or SSE1, or 8 promoted MVT::f64 values with the X86 FP stack.
1302 /// Similarly, MVT::v2i64 turns into 4 MVT::i32 values with both PPC and X86.
1303 ///
1304 /// This method returns the number of registers needed, and the VT for each
1305 /// register.  It also returns the VT and quantity of the intermediate values
1306 /// before they are promoted/expanded.
1307 unsigned TargetLoweringBase::getVectorTypeBreakdown(LLVMContext &Context, EVT VT,
1308                                                 EVT &IntermediateVT,
1309                                                 unsigned &NumIntermediates,
1310                                                 MVT &RegisterVT) const {
1311   unsigned NumElts = VT.getVectorNumElements();
1312 
1313   // If there is a wider vector type with the same element type as this one,
1314   // or a promoted vector type that has the same number of elements which
1315   // are wider, then we should convert to that legal vector type.
1316   // This handles things like <2 x float> -> <4 x float> and
1317   // <4 x i1> -> <4 x i32>.
1318   LegalizeTypeAction TA = getTypeAction(Context, VT);
1319   if (NumElts != 1 && (TA == TypeWidenVector || TA == TypePromoteInteger)) {
1320     EVT RegisterEVT = getTypeToTransformTo(Context, VT);
1321     if (isTypeLegal(RegisterEVT)) {
1322       IntermediateVT = RegisterEVT;
1323       RegisterVT = RegisterEVT.getSimpleVT();
1324       NumIntermediates = 1;
1325       return 1;
1326     }
1327   }
1328 
1329   // Figure out the right, legal destination reg to copy into.
1330   EVT EltTy = VT.getVectorElementType();
1331 
1332   unsigned NumVectorRegs = 1;
1333 
1334   // FIXME: We don't support non-power-of-2-sized vectors for now.  Ideally we
1335   // could break down into LHS/RHS like LegalizeDAG does.
1336   if (!isPowerOf2_32(NumElts)) {
1337     NumVectorRegs = NumElts;
1338     NumElts = 1;
1339   }
1340 
1341   // Divide the input until we get to a supported size.  This will always
1342   // end with a scalar if the target doesn't support vectors.
1343   while (NumElts > 1 && !isTypeLegal(
1344                                    EVT::getVectorVT(Context, EltTy, NumElts))) {
1345     NumElts >>= 1;
1346     NumVectorRegs <<= 1;
1347   }
1348 
1349   NumIntermediates = NumVectorRegs;
1350 
1351   EVT NewVT = EVT::getVectorVT(Context, EltTy, NumElts);
1352   if (!isTypeLegal(NewVT))
1353     NewVT = EltTy;
1354   IntermediateVT = NewVT;
1355 
1356   MVT DestVT = getRegisterType(Context, NewVT);
1357   RegisterVT = DestVT;
1358   unsigned NewVTSize = NewVT.getSizeInBits();
1359 
1360   // Convert sizes such as i33 to i64.
1361   if (!isPowerOf2_32(NewVTSize))
1362     NewVTSize = NextPowerOf2(NewVTSize);
1363 
1364   if (EVT(DestVT).bitsLT(NewVT))   // Value is expanded, e.g. i64 -> i16.
1365     return NumVectorRegs*(NewVTSize/DestVT.getSizeInBits());
1366 
1367   // Otherwise, promotion or legal types use the same number of registers as
1368   // the vector decimated to the appropriate level.
1369   return NumVectorRegs;
1370 }
1371 
1372 /// Get the EVTs and ArgFlags collections that represent the legalized return
1373 /// type of the given function.  This does not require a DAG or a return value,
1374 /// and is suitable for use before any DAGs for the function are constructed.
1375 /// TODO: Move this out of TargetLowering.cpp.
1376 void llvm::GetReturnInfo(CallingConv::ID CC, Type *ReturnType,
1377                          AttributeList attr,
1378                          SmallVectorImpl<ISD::OutputArg> &Outs,
1379                          const TargetLowering &TLI, const DataLayout &DL) {
1380   SmallVector<EVT, 4> ValueVTs;
1381   ComputeValueVTs(TLI, DL, ReturnType, ValueVTs);
1382   unsigned NumValues = ValueVTs.size();
1383   if (NumValues == 0) return;
1384 
1385   for (unsigned j = 0, f = NumValues; j != f; ++j) {
1386     EVT VT = ValueVTs[j];
1387     ISD::NodeType ExtendKind = ISD::ANY_EXTEND;
1388 
1389     if (attr.hasAttribute(AttributeList::ReturnIndex, Attribute::SExt))
1390       ExtendKind = ISD::SIGN_EXTEND;
1391     else if (attr.hasAttribute(AttributeList::ReturnIndex, Attribute::ZExt))
1392       ExtendKind = ISD::ZERO_EXTEND;
1393 
1394     // FIXME: C calling convention requires the return type to be promoted to
1395     // at least 32-bit. But this is not necessary for non-C calling
1396     // conventions. The frontend should mark functions whose return values
1397     // require promoting with signext or zeroext attributes.
1398     if (ExtendKind != ISD::ANY_EXTEND && VT.isInteger()) {
1399       MVT MinVT = TLI.getRegisterType(ReturnType->getContext(), MVT::i32);
1400       if (VT.bitsLT(MinVT))
1401         VT = MinVT;
1402     }
1403 
1404     unsigned NumParts =
1405         TLI.getNumRegistersForCallingConv(ReturnType->getContext(), CC, VT);
1406     MVT PartVT =
1407         TLI.getRegisterTypeForCallingConv(ReturnType->getContext(), CC, VT);
1408 
1409     // 'inreg' on function refers to return value
1410     ISD::ArgFlagsTy Flags = ISD::ArgFlagsTy();
1411     if (attr.hasAttribute(AttributeList::ReturnIndex, Attribute::InReg))
1412       Flags.setInReg();
1413 
1414     // Propagate extension type if any
1415     if (attr.hasAttribute(AttributeList::ReturnIndex, Attribute::SExt))
1416       Flags.setSExt();
1417     else if (attr.hasAttribute(AttributeList::ReturnIndex, Attribute::ZExt))
1418       Flags.setZExt();
1419 
1420     for (unsigned i = 0; i < NumParts; ++i)
1421       Outs.push_back(ISD::OutputArg(Flags, PartVT, VT, /*isFixed=*/true, 0, 0));
1422   }
1423 }
1424 
1425 /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
1426 /// function arguments in the caller parameter area.  This is the actual
1427 /// alignment, not its logarithm.
1428 unsigned TargetLoweringBase::getByValTypeAlignment(Type *Ty,
1429                                                    const DataLayout &DL) const {
1430   return DL.getABITypeAlignment(Ty);
1431 }
1432 
1433 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
1434                                             const DataLayout &DL, EVT VT,
1435                                             unsigned AddrSpace,
1436                                             unsigned Alignment,
1437                                             bool *Fast) const {
1438   // Check if the specified alignment is sufficient based on the data layout.
1439   // TODO: While using the data layout works in practice, a better solution
1440   // would be to implement this check directly (make this a virtual function).
1441   // For example, the ABI alignment may change based on software platform while
1442   // this function should only be affected by hardware implementation.
1443   Type *Ty = VT.getTypeForEVT(Context);
1444   if (Alignment >= DL.getABITypeAlignment(Ty)) {
1445     // Assume that an access that meets the ABI-specified alignment is fast.
1446     if (Fast != nullptr)
1447       *Fast = true;
1448     return true;
1449   }
1450 
1451   // This is a misaligned access.
1452   return allowsMisalignedMemoryAccesses(VT, AddrSpace, Alignment, Fast);
1453 }
1454 
1455 BranchProbability TargetLoweringBase::getPredictableBranchThreshold() const {
1456   return BranchProbability(MinPercentageForPredictableBranch, 100);
1457 }
1458 
1459 //===----------------------------------------------------------------------===//
1460 //  TargetTransformInfo Helpers
1461 //===----------------------------------------------------------------------===//
1462 
1463 int TargetLoweringBase::InstructionOpcodeToISD(unsigned Opcode) const {
1464   enum InstructionOpcodes {
1465 #define HANDLE_INST(NUM, OPCODE, CLASS) OPCODE = NUM,
1466 #define LAST_OTHER_INST(NUM) InstructionOpcodesCount = NUM
1467 #include "llvm/IR/Instruction.def"
1468   };
1469   switch (static_cast<InstructionOpcodes>(Opcode)) {
1470   case Ret:            return 0;
1471   case Br:             return 0;
1472   case Switch:         return 0;
1473   case IndirectBr:     return 0;
1474   case Invoke:         return 0;
1475   case CallBr:         return 0;
1476   case Resume:         return 0;
1477   case Unreachable:    return 0;
1478   case CleanupRet:     return 0;
1479   case CatchRet:       return 0;
1480   case CatchPad:       return 0;
1481   case CatchSwitch:    return 0;
1482   case CleanupPad:     return 0;
1483   case FNeg:           return ISD::FNEG;
1484   case Add:            return ISD::ADD;
1485   case FAdd:           return ISD::FADD;
1486   case Sub:            return ISD::SUB;
1487   case FSub:           return ISD::FSUB;
1488   case Mul:            return ISD::MUL;
1489   case FMul:           return ISD::FMUL;
1490   case UDiv:           return ISD::UDIV;
1491   case SDiv:           return ISD::SDIV;
1492   case FDiv:           return ISD::FDIV;
1493   case URem:           return ISD::UREM;
1494   case SRem:           return ISD::SREM;
1495   case FRem:           return ISD::FREM;
1496   case Shl:            return ISD::SHL;
1497   case LShr:           return ISD::SRL;
1498   case AShr:           return ISD::SRA;
1499   case And:            return ISD::AND;
1500   case Or:             return ISD::OR;
1501   case Xor:            return ISD::XOR;
1502   case Alloca:         return 0;
1503   case Load:           return ISD::LOAD;
1504   case Store:          return ISD::STORE;
1505   case GetElementPtr:  return 0;
1506   case Fence:          return 0;
1507   case AtomicCmpXchg:  return 0;
1508   case AtomicRMW:      return 0;
1509   case Trunc:          return ISD::TRUNCATE;
1510   case ZExt:           return ISD::ZERO_EXTEND;
1511   case SExt:           return ISD::SIGN_EXTEND;
1512   case FPToUI:         return ISD::FP_TO_UINT;
1513   case FPToSI:         return ISD::FP_TO_SINT;
1514   case UIToFP:         return ISD::UINT_TO_FP;
1515   case SIToFP:         return ISD::SINT_TO_FP;
1516   case FPTrunc:        return ISD::FP_ROUND;
1517   case FPExt:          return ISD::FP_EXTEND;
1518   case PtrToInt:       return ISD::BITCAST;
1519   case IntToPtr:       return ISD::BITCAST;
1520   case BitCast:        return ISD::BITCAST;
1521   case AddrSpaceCast:  return ISD::ADDRSPACECAST;
1522   case ICmp:           return ISD::SETCC;
1523   case FCmp:           return ISD::SETCC;
1524   case PHI:            return 0;
1525   case Call:           return 0;
1526   case Select:         return ISD::SELECT;
1527   case UserOp1:        return 0;
1528   case UserOp2:        return 0;
1529   case VAArg:          return 0;
1530   case ExtractElement: return ISD::EXTRACT_VECTOR_ELT;
1531   case InsertElement:  return ISD::INSERT_VECTOR_ELT;
1532   case ShuffleVector:  return ISD::VECTOR_SHUFFLE;
1533   case ExtractValue:   return ISD::MERGE_VALUES;
1534   case InsertValue:    return ISD::MERGE_VALUES;
1535   case LandingPad:     return 0;
1536   }
1537 
1538   llvm_unreachable("Unknown instruction type encountered!");
1539 }
1540 
1541 std::pair<int, MVT>
1542 TargetLoweringBase::getTypeLegalizationCost(const DataLayout &DL,
1543                                             Type *Ty) const {
1544   LLVMContext &C = Ty->getContext();
1545   EVT MTy = getValueType(DL, Ty);
1546 
1547   int Cost = 1;
1548   // We keep legalizing the type until we find a legal kind. We assume that
1549   // the only operation that costs anything is the split. After splitting
1550   // we need to handle two types.
1551   while (true) {
1552     LegalizeKind LK = getTypeConversion(C, MTy);
1553 
1554     if (LK.first == TypeLegal)
1555       return std::make_pair(Cost, MTy.getSimpleVT());
1556 
1557     if (LK.first == TypeSplitVector || LK.first == TypeExpandInteger)
1558       Cost *= 2;
1559 
1560     // Do not loop with f128 type.
1561     if (MTy == LK.second)
1562       return std::make_pair(Cost, MTy.getSimpleVT());
1563 
1564     // Keep legalizing the type.
1565     MTy = LK.second;
1566   }
1567 }
1568 
1569 Value *TargetLoweringBase::getDefaultSafeStackPointerLocation(IRBuilder<> &IRB,
1570                                                               bool UseTLS) const {
1571   // compiler-rt provides a variable with a magic name.  Targets that do not
1572   // link with compiler-rt may also provide such a variable.
1573   Module *M = IRB.GetInsertBlock()->getParent()->getParent();
1574   const char *UnsafeStackPtrVar = "__safestack_unsafe_stack_ptr";
1575   auto UnsafeStackPtr =
1576       dyn_cast_or_null<GlobalVariable>(M->getNamedValue(UnsafeStackPtrVar));
1577 
1578   Type *StackPtrTy = Type::getInt8PtrTy(M->getContext());
1579 
1580   if (!UnsafeStackPtr) {
1581     auto TLSModel = UseTLS ?
1582         GlobalValue::InitialExecTLSModel :
1583         GlobalValue::NotThreadLocal;
1584     // The global variable is not defined yet, define it ourselves.
1585     // We use the initial-exec TLS model because we do not support the
1586     // variable living anywhere other than in the main executable.
1587     UnsafeStackPtr = new GlobalVariable(
1588         *M, StackPtrTy, false, GlobalValue::ExternalLinkage, nullptr,
1589         UnsafeStackPtrVar, nullptr, TLSModel);
1590   } else {
1591     // The variable exists, check its type and attributes.
1592     if (UnsafeStackPtr->getValueType() != StackPtrTy)
1593       report_fatal_error(Twine(UnsafeStackPtrVar) + " must have void* type");
1594     if (UseTLS != UnsafeStackPtr->isThreadLocal())
1595       report_fatal_error(Twine(UnsafeStackPtrVar) + " must " +
1596                          (UseTLS ? "" : "not ") + "be thread-local");
1597   }
1598   return UnsafeStackPtr;
1599 }
1600 
1601 Value *TargetLoweringBase::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
1602   if (!TM.getTargetTriple().isAndroid())
1603     return getDefaultSafeStackPointerLocation(IRB, true);
1604 
1605   // Android provides a libc function to retrieve the address of the current
1606   // thread's unsafe stack pointer.
1607   Module *M = IRB.GetInsertBlock()->getParent()->getParent();
1608   Type *StackPtrTy = Type::getInt8PtrTy(M->getContext());
1609   FunctionCallee Fn = M->getOrInsertFunction("__safestack_pointer_address",
1610                                              StackPtrTy->getPointerTo(0));
1611   return IRB.CreateCall(Fn);
1612 }
1613 
1614 //===----------------------------------------------------------------------===//
1615 //  Loop Strength Reduction hooks
1616 //===----------------------------------------------------------------------===//
1617 
1618 /// isLegalAddressingMode - Return true if the addressing mode represented
1619 /// by AM is legal for this target, for a load/store of the specified type.
1620 bool TargetLoweringBase::isLegalAddressingMode(const DataLayout &DL,
1621                                                const AddrMode &AM, Type *Ty,
1622                                                unsigned AS, Instruction *I) const {
1623   // The default implementation of this implements a conservative RISCy, r+r and
1624   // r+i addr mode.
1625 
1626   // Allows a sign-extended 16-bit immediate field.
1627   if (AM.BaseOffs <= -(1LL << 16) || AM.BaseOffs >= (1LL << 16)-1)
1628     return false;
1629 
1630   // No global is ever allowed as a base.
1631   if (AM.BaseGV)
1632     return false;
1633 
1634   // Only support r+r,
1635   switch (AM.Scale) {
1636   case 0:  // "r+i" or just "i", depending on HasBaseReg.
1637     break;
1638   case 1:
1639     if (AM.HasBaseReg && AM.BaseOffs)  // "r+r+i" is not allowed.
1640       return false;
1641     // Otherwise we have r+r or r+i.
1642     break;
1643   case 2:
1644     if (AM.HasBaseReg || AM.BaseOffs)  // 2*r+r  or  2*r+i is not allowed.
1645       return false;
1646     // Allow 2*r as r+r.
1647     break;
1648   default: // Don't allow n * r
1649     return false;
1650   }
1651 
1652   return true;
1653 }
1654 
1655 //===----------------------------------------------------------------------===//
1656 //  Stack Protector
1657 //===----------------------------------------------------------------------===//
1658 
1659 // For OpenBSD return its special guard variable. Otherwise return nullptr,
1660 // so that SelectionDAG handle SSP.
1661 Value *TargetLoweringBase::getIRStackGuard(IRBuilder<> &IRB) const {
1662   if (getTargetMachine().getTargetTriple().isOSOpenBSD()) {
1663     Module &M = *IRB.GetInsertBlock()->getParent()->getParent();
1664     PointerType *PtrTy = Type::getInt8PtrTy(M.getContext());
1665     return M.getOrInsertGlobal("__guard_local", PtrTy);
1666   }
1667   return nullptr;
1668 }
1669 
1670 // Currently only support "standard" __stack_chk_guard.
1671 // TODO: add LOAD_STACK_GUARD support.
1672 void TargetLoweringBase::insertSSPDeclarations(Module &M) const {
1673   if (!M.getNamedValue("__stack_chk_guard"))
1674     new GlobalVariable(M, Type::getInt8PtrTy(M.getContext()), false,
1675                        GlobalVariable::ExternalLinkage,
1676                        nullptr, "__stack_chk_guard");
1677 }
1678 
1679 // Currently only support "standard" __stack_chk_guard.
1680 // TODO: add LOAD_STACK_GUARD support.
1681 Value *TargetLoweringBase::getSDagStackGuard(const Module &M) const {
1682   return M.getNamedValue("__stack_chk_guard");
1683 }
1684 
1685 Function *TargetLoweringBase::getSSPStackGuardCheck(const Module &M) const {
1686   return nullptr;
1687 }
1688 
1689 unsigned TargetLoweringBase::getMinimumJumpTableEntries() const {
1690   return MinimumJumpTableEntries;
1691 }
1692 
1693 void TargetLoweringBase::setMinimumJumpTableEntries(unsigned Val) {
1694   MinimumJumpTableEntries = Val;
1695 }
1696 
1697 unsigned TargetLoweringBase::getMinimumJumpTableDensity(bool OptForSize) const {
1698   return OptForSize ? OptsizeJumpTableDensity : JumpTableDensity;
1699 }
1700 
1701 unsigned TargetLoweringBase::getMaximumJumpTableSize() const {
1702   return MaximumJumpTableSize;
1703 }
1704 
1705 void TargetLoweringBase::setMaximumJumpTableSize(unsigned Val) {
1706   MaximumJumpTableSize = Val;
1707 }
1708 
1709 //===----------------------------------------------------------------------===//
1710 //  Reciprocal Estimates
1711 //===----------------------------------------------------------------------===//
1712 
1713 /// Get the reciprocal estimate attribute string for a function that will
1714 /// override the target defaults.
1715 static StringRef getRecipEstimateForFunc(MachineFunction &MF) {
1716   const Function &F = MF.getFunction();
1717   return F.getFnAttribute("reciprocal-estimates").getValueAsString();
1718 }
1719 
1720 /// Construct a string for the given reciprocal operation of the given type.
1721 /// This string should match the corresponding option to the front-end's
1722 /// "-mrecip" flag assuming those strings have been passed through in an
1723 /// attribute string. For example, "vec-divf" for a division of a vXf32.
1724 static std::string getReciprocalOpName(bool IsSqrt, EVT VT) {
1725   std::string Name = VT.isVector() ? "vec-" : "";
1726 
1727   Name += IsSqrt ? "sqrt" : "div";
1728 
1729   // TODO: Handle "half" or other float types?
1730   if (VT.getScalarType() == MVT::f64) {
1731     Name += "d";
1732   } else {
1733     assert(VT.getScalarType() == MVT::f32 &&
1734            "Unexpected FP type for reciprocal estimate");
1735     Name += "f";
1736   }
1737 
1738   return Name;
1739 }
1740 
1741 /// Return the character position and value (a single numeric character) of a
1742 /// customized refinement operation in the input string if it exists. Return
1743 /// false if there is no customized refinement step count.
1744 static bool parseRefinementStep(StringRef In, size_t &Position,
1745                                 uint8_t &Value) {
1746   const char RefStepToken = ':';
1747   Position = In.find(RefStepToken);
1748   if (Position == StringRef::npos)
1749     return false;
1750 
1751   StringRef RefStepString = In.substr(Position + 1);
1752   // Allow exactly one numeric character for the additional refinement
1753   // step parameter.
1754   if (RefStepString.size() == 1) {
1755     char RefStepChar = RefStepString[0];
1756     if (RefStepChar >= '0' && RefStepChar <= '9') {
1757       Value = RefStepChar - '0';
1758       return true;
1759     }
1760   }
1761   report_fatal_error("Invalid refinement step for -recip.");
1762 }
1763 
1764 /// For the input attribute string, return one of the ReciprocalEstimate enum
1765 /// status values (enabled, disabled, or not specified) for this operation on
1766 /// the specified data type.
1767 static int getOpEnabled(bool IsSqrt, EVT VT, StringRef Override) {
1768   if (Override.empty())
1769     return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1770 
1771   SmallVector<StringRef, 4> OverrideVector;
1772   Override.split(OverrideVector, ',');
1773   unsigned NumArgs = OverrideVector.size();
1774 
1775   // Check if "all", "none", or "default" was specified.
1776   if (NumArgs == 1) {
1777     // Look for an optional setting of the number of refinement steps needed
1778     // for this type of reciprocal operation.
1779     size_t RefPos;
1780     uint8_t RefSteps;
1781     if (parseRefinementStep(Override, RefPos, RefSteps)) {
1782       // Split the string for further processing.
1783       Override = Override.substr(0, RefPos);
1784     }
1785 
1786     // All reciprocal types are enabled.
1787     if (Override == "all")
1788       return TargetLoweringBase::ReciprocalEstimate::Enabled;
1789 
1790     // All reciprocal types are disabled.
1791     if (Override == "none")
1792       return TargetLoweringBase::ReciprocalEstimate::Disabled;
1793 
1794     // Target defaults for enablement are used.
1795     if (Override == "default")
1796       return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1797   }
1798 
1799   // The attribute string may omit the size suffix ('f'/'d').
1800   std::string VTName = getReciprocalOpName(IsSqrt, VT);
1801   std::string VTNameNoSize = VTName;
1802   VTNameNoSize.pop_back();
1803   static const char DisabledPrefix = '!';
1804 
1805   for (StringRef RecipType : OverrideVector) {
1806     size_t RefPos;
1807     uint8_t RefSteps;
1808     if (parseRefinementStep(RecipType, RefPos, RefSteps))
1809       RecipType = RecipType.substr(0, RefPos);
1810 
1811     // Ignore the disablement token for string matching.
1812     bool IsDisabled = RecipType[0] == DisabledPrefix;
1813     if (IsDisabled)
1814       RecipType = RecipType.substr(1);
1815 
1816     if (RecipType.equals(VTName) || RecipType.equals(VTNameNoSize))
1817       return IsDisabled ? TargetLoweringBase::ReciprocalEstimate::Disabled
1818                         : TargetLoweringBase::ReciprocalEstimate::Enabled;
1819   }
1820 
1821   return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1822 }
1823 
1824 /// For the input attribute string, return the customized refinement step count
1825 /// for this operation on the specified data type. If the step count does not
1826 /// exist, return the ReciprocalEstimate enum value for unspecified.
1827 static int getOpRefinementSteps(bool IsSqrt, EVT VT, StringRef Override) {
1828   if (Override.empty())
1829     return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1830 
1831   SmallVector<StringRef, 4> OverrideVector;
1832   Override.split(OverrideVector, ',');
1833   unsigned NumArgs = OverrideVector.size();
1834 
1835   // Check if "all", "default", or "none" was specified.
1836   if (NumArgs == 1) {
1837     // Look for an optional setting of the number of refinement steps needed
1838     // for this type of reciprocal operation.
1839     size_t RefPos;
1840     uint8_t RefSteps;
1841     if (!parseRefinementStep(Override, RefPos, RefSteps))
1842       return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1843 
1844     // Split the string for further processing.
1845     Override = Override.substr(0, RefPos);
1846     assert(Override != "none" &&
1847            "Disabled reciprocals, but specifed refinement steps?");
1848 
1849     // If this is a general override, return the specified number of steps.
1850     if (Override == "all" || Override == "default")
1851       return RefSteps;
1852   }
1853 
1854   // The attribute string may omit the size suffix ('f'/'d').
1855   std::string VTName = getReciprocalOpName(IsSqrt, VT);
1856   std::string VTNameNoSize = VTName;
1857   VTNameNoSize.pop_back();
1858 
1859   for (StringRef RecipType : OverrideVector) {
1860     size_t RefPos;
1861     uint8_t RefSteps;
1862     if (!parseRefinementStep(RecipType, RefPos, RefSteps))
1863       continue;
1864 
1865     RecipType = RecipType.substr(0, RefPos);
1866     if (RecipType.equals(VTName) || RecipType.equals(VTNameNoSize))
1867       return RefSteps;
1868   }
1869 
1870   return TargetLoweringBase::ReciprocalEstimate::Unspecified;
1871 }
1872 
1873 int TargetLoweringBase::getRecipEstimateSqrtEnabled(EVT VT,
1874                                                     MachineFunction &MF) const {
1875   return getOpEnabled(true, VT, getRecipEstimateForFunc(MF));
1876 }
1877 
1878 int TargetLoweringBase::getRecipEstimateDivEnabled(EVT VT,
1879                                                    MachineFunction &MF) const {
1880   return getOpEnabled(false, VT, getRecipEstimateForFunc(MF));
1881 }
1882 
1883 int TargetLoweringBase::getSqrtRefinementSteps(EVT VT,
1884                                                MachineFunction &MF) const {
1885   return getOpRefinementSteps(true, VT, getRecipEstimateForFunc(MF));
1886 }
1887 
1888 int TargetLoweringBase::getDivRefinementSteps(EVT VT,
1889                                               MachineFunction &MF) const {
1890   return getOpRefinementSteps(false, VT, getRecipEstimateForFunc(MF));
1891 }
1892 
1893 void TargetLoweringBase::finalizeLowering(MachineFunction &MF) const {
1894   MF.getRegInfo().freezeReservedRegs(MF);
1895 }
1896