aboutsummaryrefslogtreecommitdiffstats
path: root/utils/TableGen/IntrinsicEmitter.cpp
blob: df4d847a4d7f5ed2ae517a961c27fa80bfb4558e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
//===- IntrinsicEmitter.cpp - Generate intrinsic information --------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend emits information about intrinsic functions.
//
//===----------------------------------------------------------------------===//

#include "CodeGenIntrinsics.h"
#include "CodeGenTarget.h"
#include "SequenceToOffsetTable.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/StringMatcher.h"
#include "llvm/TableGen/TableGenBackend.h"
#include <algorithm>
using namespace llvm;

namespace {
class IntrinsicEmitter {
  RecordKeeper &Records;
  bool TargetOnly;
  std::string TargetPrefix;

public:
  IntrinsicEmitter(RecordKeeper &R, bool T)
    : Records(R), TargetOnly(T) {}

  void run(raw_ostream &OS);

  void EmitPrefix(raw_ostream &OS);

  void EmitEnumInfo(const std::vector<CodeGenIntrinsic> &Ints,
                    raw_ostream &OS);

  void EmitFnNameRecognizer(const std::vector<CodeGenIntrinsic> &Ints,
                            raw_ostream &OS);
  void EmitIntrinsicToNameTable(const std::vector<CodeGenIntrinsic> &Ints,
                                raw_ostream &OS);
  void EmitIntrinsicToOverloadTable(const std::vector<CodeGenIntrinsic> &Ints,
                                    raw_ostream &OS);
  void EmitVerifier(const std::vector<CodeGenIntrinsic> &Ints,
                    raw_ostream &OS);
  void EmitGenerator(const std::vector<CodeGenIntrinsic> &Ints,
                     raw_ostream &OS);
  void EmitAttributes(const std::vector<CodeGenIntrinsic> &Ints,
                      raw_ostream &OS);
  void EmitModRefBehavior(const std::vector<CodeGenIntrinsic> &Ints,
                          raw_ostream &OS);
  void EmitIntrinsicToGCCBuiltinMap(const std::vector<CodeGenIntrinsic> &Ints,
                                    raw_ostream &OS);
  void EmitSuffix(raw_ostream &OS);
};
} // End anonymous namespace

//===----------------------------------------------------------------------===//
// IntrinsicEmitter Implementation
//===----------------------------------------------------------------------===//

void IntrinsicEmitter::run(raw_ostream &OS) {
  emitSourceFileHeader("Intrinsic Function Source Fragment", OS);

  std::vector<CodeGenIntrinsic> Ints = LoadIntrinsics(Records, TargetOnly);

  if (TargetOnly && !Ints.empty())
    TargetPrefix = Ints[0].TargetPrefix;

  EmitPrefix(OS);

  // Emit the enum information.
  EmitEnumInfo(Ints, OS);

  // Emit the intrinsic ID -> name table.
  EmitIntrinsicToNameTable(Ints, OS);

  // Emit the intrinsic ID -> overload table.
  EmitIntrinsicToOverloadTable(Ints, OS);

  // Emit the function name recognizer.
  EmitFnNameRecognizer(Ints, OS);
  
  // Emit the intrinsic declaration generator.
  EmitGenerator(Ints, OS);
  
  // Emit the intrinsic parameter attributes.
  EmitAttributes(Ints, OS);

  // Emit intrinsic alias analysis mod/ref behavior.
  EmitModRefBehavior(Ints, OS);

  // Emit code to translate GCC builtins into LLVM intrinsics.
  EmitIntrinsicToGCCBuiltinMap(Ints, OS);

  EmitSuffix(OS);
}

void IntrinsicEmitter::EmitPrefix(raw_ostream &OS) {
  OS << "// VisualStudio defines setjmp as _setjmp\n"
        "#if defined(_MSC_VER) && defined(setjmp) && \\\n"
        "                         !defined(setjmp_undefined_for_msvc)\n"
        "#  pragma push_macro(\"setjmp\")\n"
        "#  undef setjmp\n"
        "#  define setjmp_undefined_for_msvc\n"
        "#endif\n\n";
}

void IntrinsicEmitter::EmitSuffix(raw_ostream &OS) {
  OS << "#if defined(_MSC_VER) && defined(setjmp_undefined_for_msvc)\n"
        "// let's return it to _setjmp state\n"
        "#  pragma pop_macro(\"setjmp\")\n"
        "#  undef setjmp_undefined_for_msvc\n"
        "#endif\n\n";
}

void IntrinsicEmitter::EmitEnumInfo(const std::vector<CodeGenIntrinsic> &Ints,
                                    raw_ostream &OS) {
  OS << "// Enum values for Intrinsics.h\n";
  OS << "#ifdef GET_INTRINSIC_ENUM_VALUES\n";
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    OS << "    " << Ints[i].EnumName;
    OS << ((i != e-1) ? ", " : "  ");
    OS << std::string(40-Ints[i].EnumName.size(), ' ') 
      << "// " << Ints[i].Name << "\n";
  }
  OS << "#endif\n\n";
}

void IntrinsicEmitter::
EmitFnNameRecognizer(const std::vector<CodeGenIntrinsic> &Ints, 
                     raw_ostream &OS) {
  // Build a 'first character of function name' -> intrinsic # mapping.
  std::map<char, std::vector<unsigned> > IntMapping;
  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
    IntMapping[Ints[i].Name[5]].push_back(i);
  
  OS << "// Function name -> enum value recognizer code.\n";
  OS << "#ifdef GET_FUNCTION_RECOGNIZER\n";
  OS << "  StringRef NameR(Name+6, Len-6);   // Skip over 'llvm.'\n";
  OS << "  switch (Name[5]) {                  // Dispatch on first letter.\n";
  OS << "  default: break;\n";
  // Emit the intrinsic matching stuff by first letter.
  for (std::map<char, std::vector<unsigned> >::iterator I = IntMapping.begin(),
       E = IntMapping.end(); I != E; ++I) {
    OS << "  case '" << I->first << "':\n";
    std::vector<unsigned> &IntList = I->second;

    // Emit all the overloaded intrinsics first, build a table of the
    // non-overloaded ones.
    std::vector<StringMatcher::StringPair> MatchTable;
    
    for (unsigned i = 0, e = IntList.size(); i != e; ++i) {
      unsigned IntNo = IntList[i];
      std::string Result = "return " + TargetPrefix + "Intrinsic::" +
        Ints[IntNo].EnumName + ";";

      if (!Ints[IntNo].isOverloaded) {
        MatchTable.push_back(std::make_pair(Ints[IntNo].Name.substr(6),Result));
        continue;
      }

      // For overloaded intrinsics, only the prefix needs to match
      std::string TheStr = Ints[IntNo].Name.substr(6);
      TheStr += '.';  // Require "bswap." instead of bswap.
      OS << "    if (NameR.startswith(\"" << TheStr << "\")) "
         << Result << '\n';
    }
    
    // Emit the matcher logic for the fixed length strings.
    StringMatcher("NameR", MatchTable, OS).Emit(1);
    OS << "    break;  // end of '" << I->first << "' case.\n";
  }
  
  OS << "  }\n";
  OS << "#endif\n\n";
}

void IntrinsicEmitter::
EmitIntrinsicToNameTable(const std::vector<CodeGenIntrinsic> &Ints, 
                         raw_ostream &OS) {
  OS << "// Intrinsic ID to name table\n";
  OS << "#ifdef GET_INTRINSIC_NAME_TABLE\n";
  OS << "  // Note that entry #0 is the invalid intrinsic!\n";
  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
    OS << "  \"" << Ints[i].Name << "\",\n";
  OS << "#endif\n\n";
}

void IntrinsicEmitter::
EmitIntrinsicToOverloadTable(const std::vector<CodeGenIntrinsic> &Ints, 
                         raw_ostream &OS) {
  OS << "// Intrinsic ID to overload bitset\n";
  OS << "#ifdef GET_INTRINSIC_OVERLOAD_TABLE\n";
  OS << "static const uint8_t OTable[] = {\n";
  OS << "  0";
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    // Add one to the index so we emit a null bit for the invalid #0 intrinsic.
    if ((i+1)%8 == 0)
      OS << ",\n  0";
    if (Ints[i].isOverloaded)
      OS << " | (1<<" << (i+1)%8 << ')';
  }
  OS << "\n};\n\n";
  // OTable contains a true bit at the position if the intrinsic is overloaded.
  OS << "return (OTable[id/8] & (1 << (id%8))) != 0;\n";
  OS << "#endif\n\n";
}


// NOTE: This must be kept in synch with the copy in lib/VMCore/Function.cpp!
enum IIT_Info {
  // Common values should be encoded with 0-15.
  IIT_Done = 0,
  IIT_I1   = 1,
  IIT_I8   = 2,
  IIT_I16  = 3,
  IIT_I32  = 4,
  IIT_I64  = 5,
  IIT_F16  = 6,
  IIT_F32  = 7,
  IIT_F64  = 8,
  IIT_V2   = 9,
  IIT_V4   = 10,
  IIT_V8   = 11,
  IIT_V16  = 12,
  IIT_V32  = 13,
  IIT_PTR  = 14,
  IIT_ARG  = 15,

  // Values from 16+ are only encodable with the inefficient encoding.
  IIT_MMX  = 16,
  IIT_METADATA = 17,
  IIT_EMPTYSTRUCT = 18,
  IIT_STRUCT2 = 19,
  IIT_STRUCT3 = 20,
  IIT_STRUCT4 = 21,
  IIT_STRUCT5 = 22,
  IIT_EXTEND_VEC_ARG = 23,
  IIT_TRUNC_VEC_ARG = 24,
  IIT_ANYPTR = 25
};


static void EncodeFixedValueType(MVT::SimpleValueType VT,
                                 std::vector<unsigned char> &Sig) {
  if (EVT(VT).isInteger()) {
    unsigned BitWidth = EVT(VT).getSizeInBits();
    switch (BitWidth) {
    default: PrintFatalError("unhandled integer type width in intrinsic!");
    case 1: return Sig.push_back(IIT_I1);
    case 8: return Sig.push_back(IIT_I8);
    case 16: return Sig.push_back(IIT_I16);
    case 32: return Sig.push_back(IIT_I32);
    case 64: return Sig.push_back(IIT_I64);
    }
  }
  
  switch (VT) {
  default: PrintFatalError("unhandled MVT in intrinsic!");
  case MVT::f16: return Sig.push_back(IIT_F16);
  case MVT::f32: return Sig.push_back(IIT_F32);
  case MVT::f64: return Sig.push_back(IIT_F64);
  case MVT::Metadata: return Sig.push_back(IIT_METADATA);
  case MVT::x86mmx: return Sig.push_back(IIT_MMX);
  // MVT::OtherVT is used to mean the empty struct type here.
  case MVT::Other: return Sig.push_back(IIT_EMPTYSTRUCT);
  }
}

#ifdef _MSC_VER
#pragma optimize("",off) // MSVC 2010 optimizer can't deal with this function.
#endif 

static void EncodeFixedType(Record *R, std::vector<unsigned char> &ArgCodes,
                            std::vector<unsigned char> &Sig) {
  
  if (R->isSubClassOf("LLVMMatchType")) {
    unsigned Number = R->getValueAsInt("Number");
    assert(Number < ArgCodes.size() && "Invalid matching number!");
    if (R->isSubClassOf("LLVMExtendedElementVectorType"))
      Sig.push_back(IIT_EXTEND_VEC_ARG);
    else if (R->isSubClassOf("LLVMTruncatedElementVectorType"))
      Sig.push_back(IIT_TRUNC_VEC_ARG);
    else
      Sig.push_back(IIT_ARG);
    return Sig.push_back((Number << 2) | ArgCodes[Number]);
  }
  
  MVT::SimpleValueType VT = getValueType(R->getValueAsDef("VT"));

  unsigned Tmp = 0;
  switch (VT) {
  default: break;
  case MVT::iPTRAny: ++Tmp; // FALL THROUGH.
  case MVT::vAny: ++Tmp; // FALL THROUGH.
  case MVT::fAny: ++Tmp; // FALL THROUGH.
  case MVT::iAny: {
    // If this is an "any" valuetype, then the type is the type of the next
    // type in the list specified to getIntrinsic().  
    Sig.push_back(IIT_ARG);
    
    // Figure out what arg # this is consuming, and remember what kind it was.
    unsigned ArgNo = ArgCodes.size();
    ArgCodes.push_back(Tmp);
    
    // Encode what sort of argument it must be in the low 2 bits of the ArgNo.
    return Sig.push_back((ArgNo << 2) | Tmp);
  }
  
  case MVT::iPTR: {
    unsigned AddrSpace = 0;
    if (R->isSubClassOf("LLVMQualPointerType")) {
      AddrSpace = R->getValueAsInt("AddrSpace");
      assert(AddrSpace < 256 && "Address space exceeds 255");
    }
    if (AddrSpace) {
      Sig.push_back(IIT_ANYPTR);
      Sig.push_back(AddrSpace);
    } else {
      Sig.push_back(IIT_PTR);
    }
    return EncodeFixedType(R->getValueAsDef("ElTy"), ArgCodes, Sig);
  }
  }
  
  if (EVT(VT).isVector()) {
    EVT VVT = VT;
    switch (VVT.getVectorNumElements()) {
    default: PrintFatalError("unhandled vector type width in intrinsic!");
    case 2: Sig.push_back(IIT_V2); break;
    case 4: Sig.push_back(IIT_V4); break;
    case 8: Sig.push_back(IIT_V8); break;
    case 16: Sig.push_back(IIT_V16); break;
    case 32: Sig.push_back(IIT_V32); break;
    }
    
    return EncodeFixedValueType(VVT.getVectorElementType().
                                getSimpleVT().SimpleTy, Sig);
  }

  EncodeFixedValueType(VT, Sig);
}

#ifdef _MSC_VER
#pragma optimize("",on)
#endif

/// ComputeFixedEncoding - If we can encode the type signature for this
/// intrinsic into 32 bits, return it.  If not, return ~0U.
static void ComputeFixedEncoding(const CodeGenIntrinsic &Int,
                                 std::vector<unsigned char> &TypeSig) {
  std::vector<unsigned char> ArgCodes;
  
  if (Int.IS.RetVTs.empty())
    TypeSig.push_back(IIT_Done);
  else if (Int.IS.RetVTs.size() == 1 &&
           Int.IS.RetVTs[0] == MVT::isVoid)
    TypeSig.push_back(IIT_Done);
  else {
    switch (Int.IS.RetVTs.size()) {
      case 1: break;
      case 2: TypeSig.push_back(IIT_STRUCT2); break;
      case 3: TypeSig.push_back(IIT_STRUCT3); break;
      case 4: TypeSig.push_back(IIT_STRUCT4); break;
      case 5: TypeSig.push_back(IIT_STRUCT5); break;
      default: assert(0 && "Unhandled case in struct");
    }
    
    for (unsigned i = 0, e = Int.IS.RetVTs.size(); i != e; ++i)
      EncodeFixedType(Int.IS.RetTypeDefs[i], ArgCodes, TypeSig);
  }
  
  for (unsigned i = 0, e = Int.IS.ParamTypeDefs.size(); i != e; ++i)
    EncodeFixedType(Int.IS.ParamTypeDefs[i], ArgCodes, TypeSig);
}

static void printIITEntry(raw_ostream &OS, unsigned char X) {
  OS << (unsigned)X;
}

void IntrinsicEmitter::EmitGenerator(const std::vector<CodeGenIntrinsic> &Ints, 
                                     raw_ostream &OS) {
  // If we can compute a 32-bit fixed encoding for this intrinsic, do so and
  // capture it in this vector, otherwise store a ~0U.
  std::vector<unsigned> FixedEncodings;
  
  SequenceToOffsetTable<std::vector<unsigned char> > LongEncodingTable;
  
  std::vector<unsigned char> TypeSig;
  
  // Compute the unique argument type info.
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    // Get the signature for the intrinsic.
    TypeSig.clear();
    ComputeFixedEncoding(Ints[i], TypeSig);

    // Check to see if we can encode it into a 32-bit word.  We can only encode
    // 8 nibbles into a 32-bit word.
    if (TypeSig.size() <= 8) {
      bool Failed = false;
      unsigned Result = 0;
      for (unsigned i = 0, e = TypeSig.size(); i != e; ++i) {
        // If we had an unencodable argument, bail out.
        if (TypeSig[i] > 15) {
          Failed = true;
          break;
        }
        Result = (Result << 4) | TypeSig[e-i-1];
      }
      
      // If this could be encoded into a 31-bit word, return it.
      if (!Failed && (Result >> 31) == 0) {
        FixedEncodings.push_back(Result);
        continue;
      }
    }

    // Otherwise, we're going to unique the sequence into the
    // LongEncodingTable, and use its offset in the 32-bit table instead.
    LongEncodingTable.add(TypeSig);
      
    // This is a placehold that we'll replace after the table is laid out.
    FixedEncodings.push_back(~0U);
  }
  
  LongEncodingTable.layout();
  
  OS << "// Global intrinsic function declaration type table.\n";
  OS << "#ifdef GET_INTRINSIC_GENERATOR_GLOBAL\n";

  OS << "static const unsigned IIT_Table[] = {\n  ";
  
  for (unsigned i = 0, e = FixedEncodings.size(); i != e; ++i) {
    if ((i & 7) == 7)
      OS << "\n  ";
    
    // If the entry fit in the table, just emit it.
    if (FixedEncodings[i] != ~0U) {
      OS << "0x" << utohexstr(FixedEncodings[i]) << ", ";
      continue;
    }
    
    TypeSig.clear();
    ComputeFixedEncoding(Ints[i], TypeSig);

    
    // Otherwise, emit the offset into the long encoding table.  We emit it this
    // way so that it is easier to read the offset in the .def file.
    OS << "(1U<<31) | " << LongEncodingTable.get(TypeSig) << ", ";
  }
  
  OS << "0\n};\n\n";
  
  // Emit the shared table of register lists.
  OS << "static const unsigned char IIT_LongEncodingTable[] = {\n";
  if (!LongEncodingTable.empty())
    LongEncodingTable.emit(OS, printIITEntry);
  OS << "  255\n};\n\n";
  
  OS << "#endif\n\n";  // End of GET_INTRINSIC_GENERATOR_GLOBAL
}

enum ModRefKind {
  MRK_none,
  MRK_readonly,
  MRK_readnone
};

static ModRefKind getModRefKind(const CodeGenIntrinsic &intrinsic) {
  switch (intrinsic.ModRef) {
  case CodeGenIntrinsic::NoMem:
    return MRK_readnone;
  case CodeGenIntrinsic::ReadArgMem:
  case CodeGenIntrinsic::ReadMem:
    return MRK_readonly;
  case CodeGenIntrinsic::ReadWriteArgMem:
  case CodeGenIntrinsic::ReadWriteMem:
    return MRK_none;
  }
  llvm_unreachable("bad mod-ref kind");
}

namespace {
struct AttributeComparator {
  bool operator()(const CodeGenIntrinsic *L, const CodeGenIntrinsic *R) const {
    // Sort throwing intrinsics after non-throwing intrinsics.
    if (L->canThrow != R->canThrow)
      return R->canThrow;

    if (L->isNoReturn != R->isNoReturn)
      return R->isNoReturn;

    // Try to order by readonly/readnone attribute.
    ModRefKind LK = getModRefKind(*L);
    ModRefKind RK = getModRefKind(*R);
    if (LK != RK) return (LK > RK);

    // Order by argument attributes.
    // This is reliable because each side is already sorted internally.
    return (L->ArgumentAttributes < R->ArgumentAttributes);
  }
};
} // End anonymous namespace

/// EmitAttributes - This emits the Intrinsic::getAttributes method.
void IntrinsicEmitter::
EmitAttributes(const std::vector<CodeGenIntrinsic> &Ints, raw_ostream &OS) {
  OS << "// Add parameter attributes that are not common to all intrinsics.\n";
  OS << "#ifdef GET_INTRINSIC_ATTRIBUTES\n";
  if (TargetOnly)
    OS << "static AttributeSet getAttributes(LLVMContext &C, " << TargetPrefix
       << "Intrinsic::ID id) {\n";
  else
    OS << "AttributeSet Intrinsic::getAttributes(LLVMContext &C, ID id) {\n";

  // Compute the maximum number of attribute arguments and the map
  typedef std::map<const CodeGenIntrinsic*, unsigned,
                   AttributeComparator> UniqAttrMapTy;
  UniqAttrMapTy UniqAttributes;
  unsigned maxArgAttrs = 0;
  unsigned AttrNum = 0;
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    const CodeGenIntrinsic &intrinsic = Ints[i];
    maxArgAttrs =
      std::max(maxArgAttrs, unsigned(intrinsic.ArgumentAttributes.size()));
    unsigned &N = UniqAttributes[&intrinsic];
    if (N) continue;
    assert(AttrNum < 256 && "Too many unique attributes for table!");
    N = ++AttrNum;
  }

  // Emit an array of AttributeSet.  Most intrinsics will have at least one
  // entry, for the function itself (index ~1), which is usually nounwind.
  OS << "  static const uint8_t IntrinsicsToAttributesMap[] = {\n";

  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    const CodeGenIntrinsic &intrinsic = Ints[i];

    OS << "    " << UniqAttributes[&intrinsic] << ", // "
       << intrinsic.Name << "\n";
  }
  OS << "  };\n\n";

  OS << "  AttributeSet AS[" << maxArgAttrs+1 << "];\n";
  OS << "  unsigned NumAttrs = 0;\n";
  OS << "  if (id != 0) {\n";
  OS << "    SmallVector<Attribute::AttrKind, 8> AttrVec;\n";
  OS << "    switch(IntrinsicsToAttributesMap[id - ";
  if (TargetOnly)
    OS << "Intrinsic::num_intrinsics";
  else
    OS << "1";
  OS << "]) {\n";
  OS << "    default: llvm_unreachable(\"Invalid attribute number\");\n";
  for (UniqAttrMapTy::const_iterator I = UniqAttributes.begin(),
       E = UniqAttributes.end(); I != E; ++I) {
    OS << "    case " << I->second << ":\n";

    const CodeGenIntrinsic &intrinsic = *(I->first);

    // Keep track of the number of attributes we're writing out.
    unsigned numAttrs = 0;

    // The argument attributes are alreadys sorted by argument index.
    unsigned ai = 0, ae = intrinsic.ArgumentAttributes.size();
    if (ae) {
      while (ai != ae) {
        unsigned argNo = intrinsic.ArgumentAttributes[ai].first;

        OS << "      AttrVec.clear();\n";

        do {
          switch (intrinsic.ArgumentAttributes[ai].second) {
          case CodeGenIntrinsic::NoCapture:
            OS << "      AttrVec.push_back(Attribute::NoCapture);\n";
            break;
          }

          ++ai;
        } while (ai != ae && intrinsic.ArgumentAttributes[ai].first == argNo);

        OS << "      AS[" << numAttrs++ << "] = AttributeSet::get(C, "
           << argNo+1 << ", AttrVec);\n";
      }
    }

    ModRefKind modRef = getModRefKind(intrinsic);

    if (!intrinsic.canThrow || modRef || intrinsic.isNoReturn) {
      OS << "      AttrVec.clear();\n";

      if (!intrinsic.canThrow)
        OS << "      AttrVec.push_back(Attribute::NoUnwind);\n";
      if (intrinsic.isNoReturn)
        OS << "      AttrVec.push_back(Attribute::NoReturn);\n";

      switch (modRef) {
      case MRK_none: break;
      case MRK_readonly:
        OS << "      AttrVec.push_back(Attribute::ReadOnly);\n";
        break;
      case MRK_readnone:
        OS << "      AttrVec.push_back(Attribute::ReadNone);\n"; 
        break;
      }
      OS << "      AS[" << numAttrs++ << "] = AttributeSet::get(C, "
         << "AttributeSet::FunctionIndex, AttrVec);\n";
    }

    if (numAttrs) {
      OS << "      NumAttrs = " << numAttrs << ";\n";
      OS << "      break;\n";
    } else {
      OS << "      return AttributeSet();\n";
    }
  }
  
  OS << "    }\n";
  OS << "  }\n";
  OS << "  return AttributeSet::get(C, ArrayRef<AttributeSet>(AS, "
             "NumAttrs));\n";
  OS << "}\n";
  OS << "#endif // GET_INTRINSIC_ATTRIBUTES\n\n";
}

/// EmitModRefBehavior - Determine intrinsic alias analysis mod/ref behavior.
void IntrinsicEmitter::
EmitModRefBehavior(const std::vector<CodeGenIntrinsic> &Ints, raw_ostream &OS){
  OS << "// Determine intrinsic alias analysis mod/ref behavior.\n"
     << "#ifdef GET_INTRINSIC_MODREF_BEHAVIOR\n"
     << "assert(iid <= Intrinsic::" << Ints.back().EnumName << " && "
     << "\"Unknown intrinsic.\");\n\n";

  OS << "static const uint8_t IntrinsicModRefBehavior[] = {\n"
     << "  /* invalid */ UnknownModRefBehavior,\n";
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    OS << "  /* " << TargetPrefix << Ints[i].EnumName << " */ ";
    switch (Ints[i].ModRef) {
    case CodeGenIntrinsic::NoMem:
      OS << "DoesNotAccessMemory,\n";
      break;
    case CodeGenIntrinsic::ReadArgMem:
      OS << "OnlyReadsArgumentPointees,\n";
      break;
    case CodeGenIntrinsic::ReadMem:
      OS << "OnlyReadsMemory,\n";
      break;
    case CodeGenIntrinsic::ReadWriteArgMem:
      OS << "OnlyAccessesArgumentPointees,\n";
      break;
    case CodeGenIntrinsic::ReadWriteMem:
      OS << "UnknownModRefBehavior,\n";
      break;
    }
  }
  OS << "};\n\n"
     << "return static_cast<ModRefBehavior>(IntrinsicModRefBehavior[iid]);\n"
     << "#endif // GET_INTRINSIC_MODREF_BEHAVIOR\n\n";
}

/// EmitTargetBuiltins - All of the builtins in the specified map are for the
/// same target, and we already checked it.
static void EmitTargetBuiltins(const std::map<std::string, std::string> &BIM,
                               const std::string &TargetPrefix,
                               raw_ostream &OS) {
  
  std::vector<StringMatcher::StringPair> Results;
  
  for (std::map<std::string, std::string>::const_iterator I = BIM.begin(),
       E = BIM.end(); I != E; ++I) {
    std::string ResultCode =
    "return " + TargetPrefix + "Intrinsic::" + I->second + ";";
    Results.push_back(StringMatcher::StringPair(I->first, ResultCode));
  }

  StringMatcher("BuiltinName", Results, OS).Emit();
}

        
void IntrinsicEmitter::
EmitIntrinsicToGCCBuiltinMap(const std::vector<CodeGenIntrinsic> &Ints, 
                             raw_ostream &OS) {
  typedef std::map<std::string, std::map<std::string, std::string> > BIMTy;
  BIMTy BuiltinMap;
  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
    if (!Ints[i].GCCBuiltinName.empty()) {
      // Get the map for this target prefix.
      std::map<std::string, std::string> &BIM =BuiltinMap[Ints[i].TargetPrefix];
      
      if (!BIM.insert(std::make_pair(Ints[i].GCCBuiltinName,
                                     Ints[i].EnumName)).second)
        PrintFatalError("Intrinsic '" + Ints[i].TheDef->getName() +
              "': duplicate GCC builtin name!");
    }
  }
  
  OS << "// Get the LLVM intrinsic that corresponds to a GCC builtin.\n";
  OS << "// This is used by the C front-end.  The GCC builtin name is passed\n";
  OS << "// in as BuiltinName, and a target prefix (e.g. 'ppc') is passed\n";
  OS << "// in as TargetPrefix.  The result is assigned to 'IntrinsicID'.\n";
  OS << "#ifdef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN\n";
  
  if (TargetOnly) {
    OS << "static " << TargetPrefix << "Intrinsic::ID "
       << "getIntrinsicForGCCBuiltin(const char "
       << "*TargetPrefixStr, const char *BuiltinNameStr) {\n";
  } else {
    OS << "Intrinsic::ID Intrinsic::getIntrinsicForGCCBuiltin(const char "
       << "*TargetPrefixStr, const char *BuiltinNameStr) {\n";
  }
  
  OS << "  StringRef BuiltinName(BuiltinNameStr);\n";
  OS << "  StringRef TargetPrefix(TargetPrefixStr);\n\n";
  
  // Note: this could emit significantly better code if we cared.
  for (BIMTy::iterator I = BuiltinMap.begin(), E = BuiltinMap.end();I != E;++I){
    OS << "  ";
    if (!I->first.empty())
      OS << "if (TargetPrefix == \"" << I->first << "\") ";
    else
      OS << "/* Target Independent Builtins */ ";
    OS << "{\n";

    // Emit the comparisons for this target prefix.
    EmitTargetBuiltins(I->second, TargetPrefix, OS);
    OS << "  }\n";
  }
  OS << "  return ";
  if (!TargetPrefix.empty())
    OS << "(" << TargetPrefix << "Intrinsic::ID)";
  OS << "Intrinsic::not_intrinsic;\n";
  OS << "}\n";
  OS << "#endif\n\n";
}

namespace llvm {

void EmitIntrinsics(RecordKeeper &RK, raw_ostream &OS, bool TargetOnly = false) {
  IntrinsicEmitter(RK, TargetOnly).run(OS);
}

} // End llvm namespace