xref: /freebsd/contrib/llvm-project/llvm/lib/ExecutionEngine/Interpreter/Execution.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 //===-- Execution.cpp - Implement code to simulate the program ------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file contains the actual instruction interpreter.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "Interpreter.h"
14 #include "llvm/ADT/APInt.h"
15 #include "llvm/ADT/Statistic.h"
16 #include "llvm/CodeGen/IntrinsicLowering.h"
17 #include "llvm/IR/Constants.h"
18 #include "llvm/IR/DerivedTypes.h"
19 #include "llvm/IR/GetElementPtrTypeIterator.h"
20 #include "llvm/IR/Instructions.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Support/Debug.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/MathExtras.h"
25 #include "llvm/Support/raw_ostream.h"
26 #include <algorithm>
27 #include <cmath>
28 using namespace llvm;
29 
30 #define DEBUG_TYPE "interpreter"
31 
32 STATISTIC(NumDynamicInsts, "Number of dynamic instructions executed");
33 
34 static cl::opt<bool> PrintVolatile("interpreter-print-volatile", cl::Hidden,
35           cl::desc("make the interpreter print every volatile load and store"));
36 
37 //===----------------------------------------------------------------------===//
38 //                     Various Helper Functions
39 //===----------------------------------------------------------------------===//
40 
SetValue(Value * V,GenericValue Val,ExecutionContext & SF)41 static void SetValue(Value *V, GenericValue Val, ExecutionContext &SF) {
42   SF.Values[V] = Val;
43 }
44 
45 //===----------------------------------------------------------------------===//
46 //                    Unary Instruction Implementations
47 //===----------------------------------------------------------------------===//
48 
executeFNegInst(GenericValue & Dest,GenericValue Src,Type * Ty)49 static void executeFNegInst(GenericValue &Dest, GenericValue Src, Type *Ty) {
50   switch (Ty->getTypeID()) {
51   case Type::FloatTyID:
52     Dest.FloatVal = -Src.FloatVal;
53     break;
54   case Type::DoubleTyID:
55     Dest.DoubleVal = -Src.DoubleVal;
56     break;
57   default:
58     llvm_unreachable("Unhandled type for FNeg instruction");
59   }
60 }
61 
visitUnaryOperator(UnaryOperator & I)62 void Interpreter::visitUnaryOperator(UnaryOperator &I) {
63   ExecutionContext &SF = ECStack.back();
64   Type *Ty = I.getOperand(0)->getType();
65   GenericValue Src = getOperandValue(I.getOperand(0), SF);
66   GenericValue R; // Result
67 
68   // First process vector operation
69   if (Ty->isVectorTy()) {
70     R.AggregateVal.resize(Src.AggregateVal.size());
71 
72     switch(I.getOpcode()) {
73     default:
74       llvm_unreachable("Don't know how to handle this unary operator");
75       break;
76     case Instruction::FNeg:
77       if (cast<VectorType>(Ty)->getElementType()->isFloatTy()) {
78         for (unsigned i = 0; i < R.AggregateVal.size(); ++i)
79           R.AggregateVal[i].FloatVal = -Src.AggregateVal[i].FloatVal;
80       } else if (cast<VectorType>(Ty)->getElementType()->isDoubleTy()) {
81         for (unsigned i = 0; i < R.AggregateVal.size(); ++i)
82           R.AggregateVal[i].DoubleVal = -Src.AggregateVal[i].DoubleVal;
83       } else {
84         llvm_unreachable("Unhandled type for FNeg instruction");
85       }
86       break;
87     }
88   } else {
89     switch (I.getOpcode()) {
90     default:
91       llvm_unreachable("Don't know how to handle this unary operator");
92       break;
93     case Instruction::FNeg: executeFNegInst(R, Src, Ty); break;
94     }
95   }
96   SetValue(&I, R, SF);
97 }
98 
99 //===----------------------------------------------------------------------===//
100 //                    Binary Instruction Implementations
101 //===----------------------------------------------------------------------===//
102 
103 #define IMPLEMENT_BINARY_OPERATOR(OP, TY) \
104    case Type::TY##TyID: \
105      Dest.TY##Val = Src1.TY##Val OP Src2.TY##Val; \
106      break
107 
executeFAddInst(GenericValue & Dest,GenericValue Src1,GenericValue Src2,Type * Ty)108 static void executeFAddInst(GenericValue &Dest, GenericValue Src1,
109                             GenericValue Src2, Type *Ty) {
110   switch (Ty->getTypeID()) {
111     IMPLEMENT_BINARY_OPERATOR(+, Float);
112     IMPLEMENT_BINARY_OPERATOR(+, Double);
113   default:
114     dbgs() << "Unhandled type for FAdd instruction: " << *Ty << "\n";
115     llvm_unreachable(nullptr);
116   }
117 }
118 
executeFSubInst(GenericValue & Dest,GenericValue Src1,GenericValue Src2,Type * Ty)119 static void executeFSubInst(GenericValue &Dest, GenericValue Src1,
120                             GenericValue Src2, Type *Ty) {
121   switch (Ty->getTypeID()) {
122     IMPLEMENT_BINARY_OPERATOR(-, Float);
123     IMPLEMENT_BINARY_OPERATOR(-, Double);
124   default:
125     dbgs() << "Unhandled type for FSub instruction: " << *Ty << "\n";
126     llvm_unreachable(nullptr);
127   }
128 }
129 
executeFMulInst(GenericValue & Dest,GenericValue Src1,GenericValue Src2,Type * Ty)130 static void executeFMulInst(GenericValue &Dest, GenericValue Src1,
131                             GenericValue Src2, Type *Ty) {
132   switch (Ty->getTypeID()) {
133     IMPLEMENT_BINARY_OPERATOR(*, Float);
134     IMPLEMENT_BINARY_OPERATOR(*, Double);
135   default:
136     dbgs() << "Unhandled type for FMul instruction: " << *Ty << "\n";
137     llvm_unreachable(nullptr);
138   }
139 }
140 
executeFDivInst(GenericValue & Dest,GenericValue Src1,GenericValue Src2,Type * Ty)141 static void executeFDivInst(GenericValue &Dest, GenericValue Src1,
142                             GenericValue Src2, Type *Ty) {
143   switch (Ty->getTypeID()) {
144     IMPLEMENT_BINARY_OPERATOR(/, Float);
145     IMPLEMENT_BINARY_OPERATOR(/, Double);
146   default:
147     dbgs() << "Unhandled type for FDiv instruction: " << *Ty << "\n";
148     llvm_unreachable(nullptr);
149   }
150 }
151 
executeFRemInst(GenericValue & Dest,GenericValue Src1,GenericValue Src2,Type * Ty)152 static void executeFRemInst(GenericValue &Dest, GenericValue Src1,
153                             GenericValue Src2, Type *Ty) {
154   switch (Ty->getTypeID()) {
155   case Type::FloatTyID:
156     Dest.FloatVal = fmod(Src1.FloatVal, Src2.FloatVal);
157     break;
158   case Type::DoubleTyID:
159     Dest.DoubleVal = fmod(Src1.DoubleVal, Src2.DoubleVal);
160     break;
161   default:
162     dbgs() << "Unhandled type for Rem instruction: " << *Ty << "\n";
163     llvm_unreachable(nullptr);
164   }
165 }
166 
167 #define IMPLEMENT_INTEGER_ICMP(OP, TY) \
168    case Type::IntegerTyID:  \
169       Dest.IntVal = APInt(1,Src1.IntVal.OP(Src2.IntVal)); \
170       break;
171 
172 #define IMPLEMENT_VECTOR_INTEGER_ICMP(OP, TY)                                  \
173   case Type::FixedVectorTyID:                                                  \
174   case Type::ScalableVectorTyID: {                                             \
175     assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());              \
176     Dest.AggregateVal.resize(Src1.AggregateVal.size());                        \
177     for (uint32_t _i = 0; _i < Src1.AggregateVal.size(); _i++)                 \
178       Dest.AggregateVal[_i].IntVal = APInt(                                    \
179           1, Src1.AggregateVal[_i].IntVal.OP(Src2.AggregateVal[_i].IntVal));   \
180   } break;
181 
182 // Handle pointers specially because they must be compared with only as much
183 // width as the host has.  We _do not_ want to be comparing 64 bit values when
184 // running on a 32-bit target, otherwise the upper 32 bits might mess up
185 // comparisons if they contain garbage.
186 #define IMPLEMENT_POINTER_ICMP(OP) \
187    case Type::PointerTyID: \
188       Dest.IntVal = APInt(1,(void*)(intptr_t)Src1.PointerVal OP \
189                             (void*)(intptr_t)Src2.PointerVal); \
190       break;
191 
executeICMP_EQ(GenericValue Src1,GenericValue Src2,Type * Ty)192 static GenericValue executeICMP_EQ(GenericValue Src1, GenericValue Src2,
193                                    Type *Ty) {
194   GenericValue Dest;
195   switch (Ty->getTypeID()) {
196     IMPLEMENT_INTEGER_ICMP(eq,Ty);
197     IMPLEMENT_VECTOR_INTEGER_ICMP(eq,Ty);
198     IMPLEMENT_POINTER_ICMP(==);
199   default:
200     dbgs() << "Unhandled type for ICMP_EQ predicate: " << *Ty << "\n";
201     llvm_unreachable(nullptr);
202   }
203   return Dest;
204 }
205 
executeICMP_NE(GenericValue Src1,GenericValue Src2,Type * Ty)206 static GenericValue executeICMP_NE(GenericValue Src1, GenericValue Src2,
207                                    Type *Ty) {
208   GenericValue Dest;
209   switch (Ty->getTypeID()) {
210     IMPLEMENT_INTEGER_ICMP(ne,Ty);
211     IMPLEMENT_VECTOR_INTEGER_ICMP(ne,Ty);
212     IMPLEMENT_POINTER_ICMP(!=);
213   default:
214     dbgs() << "Unhandled type for ICMP_NE predicate: " << *Ty << "\n";
215     llvm_unreachable(nullptr);
216   }
217   return Dest;
218 }
219 
executeICMP_ULT(GenericValue Src1,GenericValue Src2,Type * Ty)220 static GenericValue executeICMP_ULT(GenericValue Src1, GenericValue Src2,
221                                     Type *Ty) {
222   GenericValue Dest;
223   switch (Ty->getTypeID()) {
224     IMPLEMENT_INTEGER_ICMP(ult,Ty);
225     IMPLEMENT_VECTOR_INTEGER_ICMP(ult,Ty);
226     IMPLEMENT_POINTER_ICMP(<);
227   default:
228     dbgs() << "Unhandled type for ICMP_ULT predicate: " << *Ty << "\n";
229     llvm_unreachable(nullptr);
230   }
231   return Dest;
232 }
233 
executeICMP_SLT(GenericValue Src1,GenericValue Src2,Type * Ty)234 static GenericValue executeICMP_SLT(GenericValue Src1, GenericValue Src2,
235                                     Type *Ty) {
236   GenericValue Dest;
237   switch (Ty->getTypeID()) {
238     IMPLEMENT_INTEGER_ICMP(slt,Ty);
239     IMPLEMENT_VECTOR_INTEGER_ICMP(slt,Ty);
240     IMPLEMENT_POINTER_ICMP(<);
241   default:
242     dbgs() << "Unhandled type for ICMP_SLT predicate: " << *Ty << "\n";
243     llvm_unreachable(nullptr);
244   }
245   return Dest;
246 }
247 
executeICMP_UGT(GenericValue Src1,GenericValue Src2,Type * Ty)248 static GenericValue executeICMP_UGT(GenericValue Src1, GenericValue Src2,
249                                     Type *Ty) {
250   GenericValue Dest;
251   switch (Ty->getTypeID()) {
252     IMPLEMENT_INTEGER_ICMP(ugt,Ty);
253     IMPLEMENT_VECTOR_INTEGER_ICMP(ugt,Ty);
254     IMPLEMENT_POINTER_ICMP(>);
255   default:
256     dbgs() << "Unhandled type for ICMP_UGT predicate: " << *Ty << "\n";
257     llvm_unreachable(nullptr);
258   }
259   return Dest;
260 }
261 
executeICMP_SGT(GenericValue Src1,GenericValue Src2,Type * Ty)262 static GenericValue executeICMP_SGT(GenericValue Src1, GenericValue Src2,
263                                     Type *Ty) {
264   GenericValue Dest;
265   switch (Ty->getTypeID()) {
266     IMPLEMENT_INTEGER_ICMP(sgt,Ty);
267     IMPLEMENT_VECTOR_INTEGER_ICMP(sgt,Ty);
268     IMPLEMENT_POINTER_ICMP(>);
269   default:
270     dbgs() << "Unhandled type for ICMP_SGT predicate: " << *Ty << "\n";
271     llvm_unreachable(nullptr);
272   }
273   return Dest;
274 }
275 
executeICMP_ULE(GenericValue Src1,GenericValue Src2,Type * Ty)276 static GenericValue executeICMP_ULE(GenericValue Src1, GenericValue Src2,
277                                     Type *Ty) {
278   GenericValue Dest;
279   switch (Ty->getTypeID()) {
280     IMPLEMENT_INTEGER_ICMP(ule,Ty);
281     IMPLEMENT_VECTOR_INTEGER_ICMP(ule,Ty);
282     IMPLEMENT_POINTER_ICMP(<=);
283   default:
284     dbgs() << "Unhandled type for ICMP_ULE predicate: " << *Ty << "\n";
285     llvm_unreachable(nullptr);
286   }
287   return Dest;
288 }
289 
executeICMP_SLE(GenericValue Src1,GenericValue Src2,Type * Ty)290 static GenericValue executeICMP_SLE(GenericValue Src1, GenericValue Src2,
291                                     Type *Ty) {
292   GenericValue Dest;
293   switch (Ty->getTypeID()) {
294     IMPLEMENT_INTEGER_ICMP(sle,Ty);
295     IMPLEMENT_VECTOR_INTEGER_ICMP(sle,Ty);
296     IMPLEMENT_POINTER_ICMP(<=);
297   default:
298     dbgs() << "Unhandled type for ICMP_SLE predicate: " << *Ty << "\n";
299     llvm_unreachable(nullptr);
300   }
301   return Dest;
302 }
303 
executeICMP_UGE(GenericValue Src1,GenericValue Src2,Type * Ty)304 static GenericValue executeICMP_UGE(GenericValue Src1, GenericValue Src2,
305                                     Type *Ty) {
306   GenericValue Dest;
307   switch (Ty->getTypeID()) {
308     IMPLEMENT_INTEGER_ICMP(uge,Ty);
309     IMPLEMENT_VECTOR_INTEGER_ICMP(uge,Ty);
310     IMPLEMENT_POINTER_ICMP(>=);
311   default:
312     dbgs() << "Unhandled type for ICMP_UGE predicate: " << *Ty << "\n";
313     llvm_unreachable(nullptr);
314   }
315   return Dest;
316 }
317 
executeICMP_SGE(GenericValue Src1,GenericValue Src2,Type * Ty)318 static GenericValue executeICMP_SGE(GenericValue Src1, GenericValue Src2,
319                                     Type *Ty) {
320   GenericValue Dest;
321   switch (Ty->getTypeID()) {
322     IMPLEMENT_INTEGER_ICMP(sge,Ty);
323     IMPLEMENT_VECTOR_INTEGER_ICMP(sge,Ty);
324     IMPLEMENT_POINTER_ICMP(>=);
325   default:
326     dbgs() << "Unhandled type for ICMP_SGE predicate: " << *Ty << "\n";
327     llvm_unreachable(nullptr);
328   }
329   return Dest;
330 }
331 
visitICmpInst(ICmpInst & I)332 void Interpreter::visitICmpInst(ICmpInst &I) {
333   ExecutionContext &SF = ECStack.back();
334   Type *Ty    = I.getOperand(0)->getType();
335   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
336   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
337   GenericValue R;   // Result
338 
339   switch (I.getPredicate()) {
340   case ICmpInst::ICMP_EQ:  R = executeICMP_EQ(Src1,  Src2, Ty); break;
341   case ICmpInst::ICMP_NE:  R = executeICMP_NE(Src1,  Src2, Ty); break;
342   case ICmpInst::ICMP_ULT: R = executeICMP_ULT(Src1, Src2, Ty); break;
343   case ICmpInst::ICMP_SLT: R = executeICMP_SLT(Src1, Src2, Ty); break;
344   case ICmpInst::ICMP_UGT: R = executeICMP_UGT(Src1, Src2, Ty); break;
345   case ICmpInst::ICMP_SGT: R = executeICMP_SGT(Src1, Src2, Ty); break;
346   case ICmpInst::ICMP_ULE: R = executeICMP_ULE(Src1, Src2, Ty); break;
347   case ICmpInst::ICMP_SLE: R = executeICMP_SLE(Src1, Src2, Ty); break;
348   case ICmpInst::ICMP_UGE: R = executeICMP_UGE(Src1, Src2, Ty); break;
349   case ICmpInst::ICMP_SGE: R = executeICMP_SGE(Src1, Src2, Ty); break;
350   default:
351     dbgs() << "Don't know how to handle this ICmp predicate!\n-->" << I;
352     llvm_unreachable(nullptr);
353   }
354 
355   SetValue(&I, R, SF);
356 }
357 
358 #define IMPLEMENT_FCMP(OP, TY) \
359    case Type::TY##TyID: \
360      Dest.IntVal = APInt(1,Src1.TY##Val OP Src2.TY##Val); \
361      break
362 
363 #define IMPLEMENT_VECTOR_FCMP_T(OP, TY)                             \
364   assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());     \
365   Dest.AggregateVal.resize( Src1.AggregateVal.size() );             \
366   for( uint32_t _i=0;_i<Src1.AggregateVal.size();_i++)              \
367     Dest.AggregateVal[_i].IntVal = APInt(1,                         \
368     Src1.AggregateVal[_i].TY##Val OP Src2.AggregateVal[_i].TY##Val);\
369   break;
370 
371 #define IMPLEMENT_VECTOR_FCMP(OP)                                              \
372   case Type::FixedVectorTyID:                                                  \
373   case Type::ScalableVectorTyID:                                               \
374     if (cast<VectorType>(Ty)->getElementType()->isFloatTy()) {                 \
375       IMPLEMENT_VECTOR_FCMP_T(OP, Float);                                      \
376     } else {                                                                   \
377       IMPLEMENT_VECTOR_FCMP_T(OP, Double);                                     \
378     }
379 
executeFCMP_OEQ(GenericValue Src1,GenericValue Src2,Type * Ty)380 static GenericValue executeFCMP_OEQ(GenericValue Src1, GenericValue Src2,
381                                    Type *Ty) {
382   GenericValue Dest;
383   switch (Ty->getTypeID()) {
384     IMPLEMENT_FCMP(==, Float);
385     IMPLEMENT_FCMP(==, Double);
386     IMPLEMENT_VECTOR_FCMP(==);
387   default:
388     dbgs() << "Unhandled type for FCmp EQ instruction: " << *Ty << "\n";
389     llvm_unreachable(nullptr);
390   }
391   return Dest;
392 }
393 
394 #define IMPLEMENT_SCALAR_NANS(TY, X,Y)                                      \
395   if (TY->isFloatTy()) {                                                    \
396     if (X.FloatVal != X.FloatVal || Y.FloatVal != Y.FloatVal) {             \
397       Dest.IntVal = APInt(1,false);                                         \
398       return Dest;                                                          \
399     }                                                                       \
400   } else {                                                                  \
401     if (X.DoubleVal != X.DoubleVal || Y.DoubleVal != Y.DoubleVal) {         \
402       Dest.IntVal = APInt(1,false);                                         \
403       return Dest;                                                          \
404     }                                                                       \
405   }
406 
407 #define MASK_VECTOR_NANS_T(X,Y, TZ, FLAG)                                   \
408   assert(X.AggregateVal.size() == Y.AggregateVal.size());                   \
409   Dest.AggregateVal.resize( X.AggregateVal.size() );                        \
410   for( uint32_t _i=0;_i<X.AggregateVal.size();_i++) {                       \
411     if (X.AggregateVal[_i].TZ##Val != X.AggregateVal[_i].TZ##Val ||         \
412         Y.AggregateVal[_i].TZ##Val != Y.AggregateVal[_i].TZ##Val)           \
413       Dest.AggregateVal[_i].IntVal = APInt(1,FLAG);                         \
414     else  {                                                                 \
415       Dest.AggregateVal[_i].IntVal = APInt(1,!FLAG);                        \
416     }                                                                       \
417   }
418 
419 #define MASK_VECTOR_NANS(TY, X,Y, FLAG)                                     \
420   if (TY->isVectorTy()) {                                                   \
421     if (cast<VectorType>(TY)->getElementType()->isFloatTy()) {              \
422       MASK_VECTOR_NANS_T(X, Y, Float, FLAG)                                 \
423     } else {                                                                \
424       MASK_VECTOR_NANS_T(X, Y, Double, FLAG)                                \
425     }                                                                       \
426   }                                                                         \
427 
428 
429 
executeFCMP_ONE(GenericValue Src1,GenericValue Src2,Type * Ty)430 static GenericValue executeFCMP_ONE(GenericValue Src1, GenericValue Src2,
431                                     Type *Ty)
432 {
433   GenericValue Dest;
434   // if input is scalar value and Src1 or Src2 is NaN return false
435   IMPLEMENT_SCALAR_NANS(Ty, Src1, Src2)
436   // if vector input detect NaNs and fill mask
437   MASK_VECTOR_NANS(Ty, Src1, Src2, false)
438   GenericValue DestMask = Dest;
439   switch (Ty->getTypeID()) {
440     IMPLEMENT_FCMP(!=, Float);
441     IMPLEMENT_FCMP(!=, Double);
442     IMPLEMENT_VECTOR_FCMP(!=);
443     default:
444       dbgs() << "Unhandled type for FCmp NE instruction: " << *Ty << "\n";
445       llvm_unreachable(nullptr);
446   }
447   // in vector case mask out NaN elements
448   if (Ty->isVectorTy())
449     for( size_t _i=0; _i<Src1.AggregateVal.size(); _i++)
450       if (DestMask.AggregateVal[_i].IntVal == false)
451         Dest.AggregateVal[_i].IntVal = APInt(1,false);
452 
453   return Dest;
454 }
455 
executeFCMP_OLE(GenericValue Src1,GenericValue Src2,Type * Ty)456 static GenericValue executeFCMP_OLE(GenericValue Src1, GenericValue Src2,
457                                    Type *Ty) {
458   GenericValue Dest;
459   switch (Ty->getTypeID()) {
460     IMPLEMENT_FCMP(<=, Float);
461     IMPLEMENT_FCMP(<=, Double);
462     IMPLEMENT_VECTOR_FCMP(<=);
463   default:
464     dbgs() << "Unhandled type for FCmp LE instruction: " << *Ty << "\n";
465     llvm_unreachable(nullptr);
466   }
467   return Dest;
468 }
469 
executeFCMP_OGE(GenericValue Src1,GenericValue Src2,Type * Ty)470 static GenericValue executeFCMP_OGE(GenericValue Src1, GenericValue Src2,
471                                    Type *Ty) {
472   GenericValue Dest;
473   switch (Ty->getTypeID()) {
474     IMPLEMENT_FCMP(>=, Float);
475     IMPLEMENT_FCMP(>=, Double);
476     IMPLEMENT_VECTOR_FCMP(>=);
477   default:
478     dbgs() << "Unhandled type for FCmp GE instruction: " << *Ty << "\n";
479     llvm_unreachable(nullptr);
480   }
481   return Dest;
482 }
483 
executeFCMP_OLT(GenericValue Src1,GenericValue Src2,Type * Ty)484 static GenericValue executeFCMP_OLT(GenericValue Src1, GenericValue Src2,
485                                    Type *Ty) {
486   GenericValue Dest;
487   switch (Ty->getTypeID()) {
488     IMPLEMENT_FCMP(<, Float);
489     IMPLEMENT_FCMP(<, Double);
490     IMPLEMENT_VECTOR_FCMP(<);
491   default:
492     dbgs() << "Unhandled type for FCmp LT instruction: " << *Ty << "\n";
493     llvm_unreachable(nullptr);
494   }
495   return Dest;
496 }
497 
executeFCMP_OGT(GenericValue Src1,GenericValue Src2,Type * Ty)498 static GenericValue executeFCMP_OGT(GenericValue Src1, GenericValue Src2,
499                                      Type *Ty) {
500   GenericValue Dest;
501   switch (Ty->getTypeID()) {
502     IMPLEMENT_FCMP(>, Float);
503     IMPLEMENT_FCMP(>, Double);
504     IMPLEMENT_VECTOR_FCMP(>);
505   default:
506     dbgs() << "Unhandled type for FCmp GT instruction: " << *Ty << "\n";
507     llvm_unreachable(nullptr);
508   }
509   return Dest;
510 }
511 
512 #define IMPLEMENT_UNORDERED(TY, X,Y)                                     \
513   if (TY->isFloatTy()) {                                                 \
514     if (X.FloatVal != X.FloatVal || Y.FloatVal != Y.FloatVal) {          \
515       Dest.IntVal = APInt(1,true);                                       \
516       return Dest;                                                       \
517     }                                                                    \
518   } else if (X.DoubleVal != X.DoubleVal || Y.DoubleVal != Y.DoubleVal) { \
519     Dest.IntVal = APInt(1,true);                                         \
520     return Dest;                                                         \
521   }
522 
523 #define IMPLEMENT_VECTOR_UNORDERED(TY, X, Y, FUNC)                             \
524   if (TY->isVectorTy()) {                                                      \
525     GenericValue DestMask = Dest;                                              \
526     Dest = FUNC(Src1, Src2, Ty);                                               \
527     for (size_t _i = 0; _i < Src1.AggregateVal.size(); _i++)                   \
528       if (DestMask.AggregateVal[_i].IntVal == true)                            \
529         Dest.AggregateVal[_i].IntVal = APInt(1, true);                         \
530     return Dest;                                                               \
531   }
532 
executeFCMP_UEQ(GenericValue Src1,GenericValue Src2,Type * Ty)533 static GenericValue executeFCMP_UEQ(GenericValue Src1, GenericValue Src2,
534                                    Type *Ty) {
535   GenericValue Dest;
536   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
537   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
538   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_OEQ)
539   return executeFCMP_OEQ(Src1, Src2, Ty);
540 
541 }
542 
executeFCMP_UNE(GenericValue Src1,GenericValue Src2,Type * Ty)543 static GenericValue executeFCMP_UNE(GenericValue Src1, GenericValue Src2,
544                                    Type *Ty) {
545   GenericValue Dest;
546   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
547   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
548   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_ONE)
549   return executeFCMP_ONE(Src1, Src2, Ty);
550 }
551 
executeFCMP_ULE(GenericValue Src1,GenericValue Src2,Type * Ty)552 static GenericValue executeFCMP_ULE(GenericValue Src1, GenericValue Src2,
553                                    Type *Ty) {
554   GenericValue Dest;
555   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
556   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
557   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_OLE)
558   return executeFCMP_OLE(Src1, Src2, Ty);
559 }
560 
executeFCMP_UGE(GenericValue Src1,GenericValue Src2,Type * Ty)561 static GenericValue executeFCMP_UGE(GenericValue Src1, GenericValue Src2,
562                                    Type *Ty) {
563   GenericValue Dest;
564   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
565   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
566   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_OGE)
567   return executeFCMP_OGE(Src1, Src2, Ty);
568 }
569 
executeFCMP_ULT(GenericValue Src1,GenericValue Src2,Type * Ty)570 static GenericValue executeFCMP_ULT(GenericValue Src1, GenericValue Src2,
571                                    Type *Ty) {
572   GenericValue Dest;
573   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
574   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
575   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_OLT)
576   return executeFCMP_OLT(Src1, Src2, Ty);
577 }
578 
executeFCMP_UGT(GenericValue Src1,GenericValue Src2,Type * Ty)579 static GenericValue executeFCMP_UGT(GenericValue Src1, GenericValue Src2,
580                                      Type *Ty) {
581   GenericValue Dest;
582   IMPLEMENT_UNORDERED(Ty, Src1, Src2)
583   MASK_VECTOR_NANS(Ty, Src1, Src2, true)
584   IMPLEMENT_VECTOR_UNORDERED(Ty, Src1, Src2, executeFCMP_OGT)
585   return executeFCMP_OGT(Src1, Src2, Ty);
586 }
587 
executeFCMP_ORD(GenericValue Src1,GenericValue Src2,Type * Ty)588 static GenericValue executeFCMP_ORD(GenericValue Src1, GenericValue Src2,
589                                      Type *Ty) {
590   GenericValue Dest;
591   if(Ty->isVectorTy()) {
592     assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());
593     Dest.AggregateVal.resize( Src1.AggregateVal.size() );
594     if (cast<VectorType>(Ty)->getElementType()->isFloatTy()) {
595       for( size_t _i=0;_i<Src1.AggregateVal.size();_i++)
596         Dest.AggregateVal[_i].IntVal = APInt(1,
597         ( (Src1.AggregateVal[_i].FloatVal ==
598         Src1.AggregateVal[_i].FloatVal) &&
599         (Src2.AggregateVal[_i].FloatVal ==
600         Src2.AggregateVal[_i].FloatVal)));
601     } else {
602       for( size_t _i=0;_i<Src1.AggregateVal.size();_i++)
603         Dest.AggregateVal[_i].IntVal = APInt(1,
604         ( (Src1.AggregateVal[_i].DoubleVal ==
605         Src1.AggregateVal[_i].DoubleVal) &&
606         (Src2.AggregateVal[_i].DoubleVal ==
607         Src2.AggregateVal[_i].DoubleVal)));
608     }
609   } else if (Ty->isFloatTy())
610     Dest.IntVal = APInt(1,(Src1.FloatVal == Src1.FloatVal &&
611                            Src2.FloatVal == Src2.FloatVal));
612   else {
613     Dest.IntVal = APInt(1,(Src1.DoubleVal == Src1.DoubleVal &&
614                            Src2.DoubleVal == Src2.DoubleVal));
615   }
616   return Dest;
617 }
618 
executeFCMP_UNO(GenericValue Src1,GenericValue Src2,Type * Ty)619 static GenericValue executeFCMP_UNO(GenericValue Src1, GenericValue Src2,
620                                      Type *Ty) {
621   GenericValue Dest;
622   if(Ty->isVectorTy()) {
623     assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());
624     Dest.AggregateVal.resize( Src1.AggregateVal.size() );
625     if (cast<VectorType>(Ty)->getElementType()->isFloatTy()) {
626       for( size_t _i=0;_i<Src1.AggregateVal.size();_i++)
627         Dest.AggregateVal[_i].IntVal = APInt(1,
628         ( (Src1.AggregateVal[_i].FloatVal !=
629            Src1.AggregateVal[_i].FloatVal) ||
630           (Src2.AggregateVal[_i].FloatVal !=
631            Src2.AggregateVal[_i].FloatVal)));
632       } else {
633         for( size_t _i=0;_i<Src1.AggregateVal.size();_i++)
634           Dest.AggregateVal[_i].IntVal = APInt(1,
635           ( (Src1.AggregateVal[_i].DoubleVal !=
636              Src1.AggregateVal[_i].DoubleVal) ||
637             (Src2.AggregateVal[_i].DoubleVal !=
638              Src2.AggregateVal[_i].DoubleVal)));
639       }
640   } else if (Ty->isFloatTy())
641     Dest.IntVal = APInt(1,(Src1.FloatVal != Src1.FloatVal ||
642                            Src2.FloatVal != Src2.FloatVal));
643   else {
644     Dest.IntVal = APInt(1,(Src1.DoubleVal != Src1.DoubleVal ||
645                            Src2.DoubleVal != Src2.DoubleVal));
646   }
647   return Dest;
648 }
649 
executeFCMP_BOOL(GenericValue Src1,GenericValue Src2,Type * Ty,const bool val)650 static GenericValue executeFCMP_BOOL(GenericValue Src1, GenericValue Src2,
651                                      Type *Ty, const bool val) {
652   GenericValue Dest;
653     if(Ty->isVectorTy()) {
654       assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());
655       Dest.AggregateVal.resize( Src1.AggregateVal.size() );
656       for( size_t _i=0; _i<Src1.AggregateVal.size(); _i++)
657         Dest.AggregateVal[_i].IntVal = APInt(1,val);
658     } else {
659       Dest.IntVal = APInt(1, val);
660     }
661 
662     return Dest;
663 }
664 
visitFCmpInst(FCmpInst & I)665 void Interpreter::visitFCmpInst(FCmpInst &I) {
666   ExecutionContext &SF = ECStack.back();
667   Type *Ty    = I.getOperand(0)->getType();
668   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
669   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
670   GenericValue R;   // Result
671 
672   switch (I.getPredicate()) {
673   default:
674     dbgs() << "Don't know how to handle this FCmp predicate!\n-->" << I;
675     llvm_unreachable(nullptr);
676   break;
677   case FCmpInst::FCMP_FALSE: R = executeFCMP_BOOL(Src1, Src2, Ty, false);
678   break;
679   case FCmpInst::FCMP_TRUE:  R = executeFCMP_BOOL(Src1, Src2, Ty, true);
680   break;
681   case FCmpInst::FCMP_ORD:   R = executeFCMP_ORD(Src1, Src2, Ty); break;
682   case FCmpInst::FCMP_UNO:   R = executeFCMP_UNO(Src1, Src2, Ty); break;
683   case FCmpInst::FCMP_UEQ:   R = executeFCMP_UEQ(Src1, Src2, Ty); break;
684   case FCmpInst::FCMP_OEQ:   R = executeFCMP_OEQ(Src1, Src2, Ty); break;
685   case FCmpInst::FCMP_UNE:   R = executeFCMP_UNE(Src1, Src2, Ty); break;
686   case FCmpInst::FCMP_ONE:   R = executeFCMP_ONE(Src1, Src2, Ty); break;
687   case FCmpInst::FCMP_ULT:   R = executeFCMP_ULT(Src1, Src2, Ty); break;
688   case FCmpInst::FCMP_OLT:   R = executeFCMP_OLT(Src1, Src2, Ty); break;
689   case FCmpInst::FCMP_UGT:   R = executeFCMP_UGT(Src1, Src2, Ty); break;
690   case FCmpInst::FCMP_OGT:   R = executeFCMP_OGT(Src1, Src2, Ty); break;
691   case FCmpInst::FCMP_ULE:   R = executeFCMP_ULE(Src1, Src2, Ty); break;
692   case FCmpInst::FCMP_OLE:   R = executeFCMP_OLE(Src1, Src2, Ty); break;
693   case FCmpInst::FCMP_UGE:   R = executeFCMP_UGE(Src1, Src2, Ty); break;
694   case FCmpInst::FCMP_OGE:   R = executeFCMP_OGE(Src1, Src2, Ty); break;
695   }
696 
697   SetValue(&I, R, SF);
698 }
699 
visitBinaryOperator(BinaryOperator & I)700 void Interpreter::visitBinaryOperator(BinaryOperator &I) {
701   ExecutionContext &SF = ECStack.back();
702   Type *Ty    = I.getOperand(0)->getType();
703   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
704   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
705   GenericValue R;   // Result
706 
707   // First process vector operation
708   if (Ty->isVectorTy()) {
709     assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());
710     R.AggregateVal.resize(Src1.AggregateVal.size());
711 
712     // Macros to execute binary operation 'OP' over integer vectors
713 #define INTEGER_VECTOR_OPERATION(OP)                               \
714     for (unsigned i = 0; i < R.AggregateVal.size(); ++i)           \
715       R.AggregateVal[i].IntVal =                                   \
716       Src1.AggregateVal[i].IntVal OP Src2.AggregateVal[i].IntVal;
717 
718     // Additional macros to execute binary operations udiv/sdiv/urem/srem since
719     // they have different notation.
720 #define INTEGER_VECTOR_FUNCTION(OP)                                \
721     for (unsigned i = 0; i < R.AggregateVal.size(); ++i)           \
722       R.AggregateVal[i].IntVal =                                   \
723       Src1.AggregateVal[i].IntVal.OP(Src2.AggregateVal[i].IntVal);
724 
725     // Macros to execute binary operation 'OP' over floating point type TY
726     // (float or double) vectors
727 #define FLOAT_VECTOR_FUNCTION(OP, TY)                               \
728       for (unsigned i = 0; i < R.AggregateVal.size(); ++i)          \
729         R.AggregateVal[i].TY =                                      \
730         Src1.AggregateVal[i].TY OP Src2.AggregateVal[i].TY;
731 
732     // Macros to choose appropriate TY: float or double and run operation
733     // execution
734 #define FLOAT_VECTOR_OP(OP) {                                         \
735   if (cast<VectorType>(Ty)->getElementType()->isFloatTy())            \
736     FLOAT_VECTOR_FUNCTION(OP, FloatVal)                               \
737   else {                                                              \
738     if (cast<VectorType>(Ty)->getElementType()->isDoubleTy())         \
739       FLOAT_VECTOR_FUNCTION(OP, DoubleVal)                            \
740     else {                                                            \
741       dbgs() << "Unhandled type for OP instruction: " << *Ty << "\n"; \
742       llvm_unreachable(0);                                            \
743     }                                                                 \
744   }                                                                   \
745 }
746 
747     switch(I.getOpcode()){
748     default:
749       dbgs() << "Don't know how to handle this binary operator!\n-->" << I;
750       llvm_unreachable(nullptr);
751       break;
752     case Instruction::Add:   INTEGER_VECTOR_OPERATION(+) break;
753     case Instruction::Sub:   INTEGER_VECTOR_OPERATION(-) break;
754     case Instruction::Mul:   INTEGER_VECTOR_OPERATION(*) break;
755     case Instruction::UDiv:  INTEGER_VECTOR_FUNCTION(udiv) break;
756     case Instruction::SDiv:  INTEGER_VECTOR_FUNCTION(sdiv) break;
757     case Instruction::URem:  INTEGER_VECTOR_FUNCTION(urem) break;
758     case Instruction::SRem:  INTEGER_VECTOR_FUNCTION(srem) break;
759     case Instruction::And:   INTEGER_VECTOR_OPERATION(&) break;
760     case Instruction::Or:    INTEGER_VECTOR_OPERATION(|) break;
761     case Instruction::Xor:   INTEGER_VECTOR_OPERATION(^) break;
762     case Instruction::FAdd:  FLOAT_VECTOR_OP(+) break;
763     case Instruction::FSub:  FLOAT_VECTOR_OP(-) break;
764     case Instruction::FMul:  FLOAT_VECTOR_OP(*) break;
765     case Instruction::FDiv:  FLOAT_VECTOR_OP(/) break;
766     case Instruction::FRem:
767       if (cast<VectorType>(Ty)->getElementType()->isFloatTy())
768         for (unsigned i = 0; i < R.AggregateVal.size(); ++i)
769           R.AggregateVal[i].FloatVal =
770           fmod(Src1.AggregateVal[i].FloatVal, Src2.AggregateVal[i].FloatVal);
771       else {
772         if (cast<VectorType>(Ty)->getElementType()->isDoubleTy())
773           for (unsigned i = 0; i < R.AggregateVal.size(); ++i)
774             R.AggregateVal[i].DoubleVal =
775             fmod(Src1.AggregateVal[i].DoubleVal, Src2.AggregateVal[i].DoubleVal);
776         else {
777           dbgs() << "Unhandled type for Rem instruction: " << *Ty << "\n";
778           llvm_unreachable(nullptr);
779         }
780       }
781       break;
782     }
783   } else {
784     switch (I.getOpcode()) {
785     default:
786       dbgs() << "Don't know how to handle this binary operator!\n-->" << I;
787       llvm_unreachable(nullptr);
788       break;
789     case Instruction::Add:   R.IntVal = Src1.IntVal + Src2.IntVal; break;
790     case Instruction::Sub:   R.IntVal = Src1.IntVal - Src2.IntVal; break;
791     case Instruction::Mul:   R.IntVal = Src1.IntVal * Src2.IntVal; break;
792     case Instruction::FAdd:  executeFAddInst(R, Src1, Src2, Ty); break;
793     case Instruction::FSub:  executeFSubInst(R, Src1, Src2, Ty); break;
794     case Instruction::FMul:  executeFMulInst(R, Src1, Src2, Ty); break;
795     case Instruction::FDiv:  executeFDivInst(R, Src1, Src2, Ty); break;
796     case Instruction::FRem:  executeFRemInst(R, Src1, Src2, Ty); break;
797     case Instruction::UDiv:  R.IntVal = Src1.IntVal.udiv(Src2.IntVal); break;
798     case Instruction::SDiv:  R.IntVal = Src1.IntVal.sdiv(Src2.IntVal); break;
799     case Instruction::URem:  R.IntVal = Src1.IntVal.urem(Src2.IntVal); break;
800     case Instruction::SRem:  R.IntVal = Src1.IntVal.srem(Src2.IntVal); break;
801     case Instruction::And:   R.IntVal = Src1.IntVal & Src2.IntVal; break;
802     case Instruction::Or:    R.IntVal = Src1.IntVal | Src2.IntVal; break;
803     case Instruction::Xor:   R.IntVal = Src1.IntVal ^ Src2.IntVal; break;
804     }
805   }
806   SetValue(&I, R, SF);
807 }
808 
executeSelectInst(GenericValue Src1,GenericValue Src2,GenericValue Src3,Type * Ty)809 static GenericValue executeSelectInst(GenericValue Src1, GenericValue Src2,
810                                       GenericValue Src3, Type *Ty) {
811     GenericValue Dest;
812     if(Ty->isVectorTy()) {
813       assert(Src1.AggregateVal.size() == Src2.AggregateVal.size());
814       assert(Src2.AggregateVal.size() == Src3.AggregateVal.size());
815       Dest.AggregateVal.resize( Src1.AggregateVal.size() );
816       for (size_t i = 0; i < Src1.AggregateVal.size(); ++i)
817         Dest.AggregateVal[i] = (Src1.AggregateVal[i].IntVal == 0) ?
818           Src3.AggregateVal[i] : Src2.AggregateVal[i];
819     } else {
820       Dest = (Src1.IntVal == 0) ? Src3 : Src2;
821     }
822     return Dest;
823 }
824 
visitSelectInst(SelectInst & I)825 void Interpreter::visitSelectInst(SelectInst &I) {
826   ExecutionContext &SF = ECStack.back();
827   Type * Ty = I.getOperand(0)->getType();
828   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
829   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
830   GenericValue Src3 = getOperandValue(I.getOperand(2), SF);
831   GenericValue R = executeSelectInst(Src1, Src2, Src3, Ty);
832   SetValue(&I, R, SF);
833 }
834 
835 //===----------------------------------------------------------------------===//
836 //                     Terminator Instruction Implementations
837 //===----------------------------------------------------------------------===//
838 
exitCalled(GenericValue GV)839 void Interpreter::exitCalled(GenericValue GV) {
840   // runAtExitHandlers() assumes there are no stack frames, but
841   // if exit() was called, then it had a stack frame. Blow away
842   // the stack before interpreting atexit handlers.
843   ECStack.clear();
844   runAtExitHandlers();
845   exit(GV.IntVal.zextOrTrunc(32).getZExtValue());
846 }
847 
848 /// Pop the last stack frame off of ECStack and then copy the result
849 /// back into the result variable if we are not returning void. The
850 /// result variable may be the ExitValue, or the Value of the calling
851 /// CallInst if there was a previous stack frame. This method may
852 /// invalidate any ECStack iterators you have. This method also takes
853 /// care of switching to the normal destination BB, if we are returning
854 /// from an invoke.
855 ///
popStackAndReturnValueToCaller(Type * RetTy,GenericValue Result)856 void Interpreter::popStackAndReturnValueToCaller(Type *RetTy,
857                                                  GenericValue Result) {
858   // Pop the current stack frame.
859   ECStack.pop_back();
860 
861   if (ECStack.empty()) {  // Finished main.  Put result into exit code...
862     if (RetTy && !RetTy->isVoidTy()) {          // Nonvoid return type?
863       ExitValue = Result;   // Capture the exit value of the program
864     } else {
865       memset(&ExitValue.Untyped, 0, sizeof(ExitValue.Untyped));
866     }
867   } else {
868     // If we have a previous stack frame, and we have a previous call,
869     // fill in the return value...
870     ExecutionContext &CallingSF = ECStack.back();
871     if (CallingSF.Caller) {
872       // Save result...
873       if (!CallingSF.Caller->getType()->isVoidTy())
874         SetValue(CallingSF.Caller, Result, CallingSF);
875       if (InvokeInst *II = dyn_cast<InvokeInst>(CallingSF.Caller))
876         SwitchToNewBasicBlock (II->getNormalDest (), CallingSF);
877       CallingSF.Caller = nullptr;             // We returned from the call...
878     }
879   }
880 }
881 
visitReturnInst(ReturnInst & I)882 void Interpreter::visitReturnInst(ReturnInst &I) {
883   ExecutionContext &SF = ECStack.back();
884   Type *RetTy = Type::getVoidTy(I.getContext());
885   GenericValue Result;
886 
887   // Save away the return value... (if we are not 'ret void')
888   if (I.getNumOperands()) {
889     RetTy  = I.getReturnValue()->getType();
890     Result = getOperandValue(I.getReturnValue(), SF);
891   }
892 
893   popStackAndReturnValueToCaller(RetTy, Result);
894 }
895 
visitUnreachableInst(UnreachableInst & I)896 void Interpreter::visitUnreachableInst(UnreachableInst &I) {
897   report_fatal_error("Program executed an 'unreachable' instruction!");
898 }
899 
visitBranchInst(BranchInst & I)900 void Interpreter::visitBranchInst(BranchInst &I) {
901   ExecutionContext &SF = ECStack.back();
902   BasicBlock *Dest;
903 
904   Dest = I.getSuccessor(0);          // Uncond branches have a fixed dest...
905   if (!I.isUnconditional()) {
906     Value *Cond = I.getCondition();
907     if (getOperandValue(Cond, SF).IntVal == 0) // If false cond...
908       Dest = I.getSuccessor(1);
909   }
910   SwitchToNewBasicBlock(Dest, SF);
911 }
912 
visitSwitchInst(SwitchInst & I)913 void Interpreter::visitSwitchInst(SwitchInst &I) {
914   ExecutionContext &SF = ECStack.back();
915   Value* Cond = I.getCondition();
916   Type *ElTy = Cond->getType();
917   GenericValue CondVal = getOperandValue(Cond, SF);
918 
919   // Check to see if any of the cases match...
920   BasicBlock *Dest = nullptr;
921   for (auto Case : I.cases()) {
922     GenericValue CaseVal = getOperandValue(Case.getCaseValue(), SF);
923     if (executeICMP_EQ(CondVal, CaseVal, ElTy).IntVal != 0) {
924       Dest = cast<BasicBlock>(Case.getCaseSuccessor());
925       break;
926     }
927   }
928   if (!Dest) Dest = I.getDefaultDest();   // No cases matched: use default
929   SwitchToNewBasicBlock(Dest, SF);
930 }
931 
visitIndirectBrInst(IndirectBrInst & I)932 void Interpreter::visitIndirectBrInst(IndirectBrInst &I) {
933   ExecutionContext &SF = ECStack.back();
934   void *Dest = GVTOP(getOperandValue(I.getAddress(), SF));
935   SwitchToNewBasicBlock((BasicBlock*)Dest, SF);
936 }
937 
938 
939 // SwitchToNewBasicBlock - This method is used to jump to a new basic block.
940 // This function handles the actual updating of block and instruction iterators
941 // as well as execution of all of the PHI nodes in the destination block.
942 //
943 // This method does this because all of the PHI nodes must be executed
944 // atomically, reading their inputs before any of the results are updated.  Not
945 // doing this can cause problems if the PHI nodes depend on other PHI nodes for
946 // their inputs.  If the input PHI node is updated before it is read, incorrect
947 // results can happen.  Thus we use a two phase approach.
948 //
SwitchToNewBasicBlock(BasicBlock * Dest,ExecutionContext & SF)949 void Interpreter::SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF){
950   BasicBlock *PrevBB = SF.CurBB;      // Remember where we came from...
951   SF.CurBB   = Dest;                  // Update CurBB to branch destination
952   SF.CurInst = SF.CurBB->begin();     // Update new instruction ptr...
953 
954   if (!isa<PHINode>(SF.CurInst)) return;  // Nothing fancy to do
955 
956   // Loop over all of the PHI nodes in the current block, reading their inputs.
957   std::vector<GenericValue> ResultValues;
958 
959   for (; PHINode *PN = dyn_cast<PHINode>(SF.CurInst); ++SF.CurInst) {
960     // Search for the value corresponding to this previous bb...
961     int i = PN->getBasicBlockIndex(PrevBB);
962     assert(i != -1 && "PHINode doesn't contain entry for predecessor??");
963     Value *IncomingValue = PN->getIncomingValue(i);
964 
965     // Save the incoming value for this PHI node...
966     ResultValues.push_back(getOperandValue(IncomingValue, SF));
967   }
968 
969   // Now loop over all of the PHI nodes setting their values...
970   SF.CurInst = SF.CurBB->begin();
971   for (unsigned i = 0; isa<PHINode>(SF.CurInst); ++SF.CurInst, ++i) {
972     PHINode *PN = cast<PHINode>(SF.CurInst);
973     SetValue(PN, ResultValues[i], SF);
974   }
975 }
976 
977 //===----------------------------------------------------------------------===//
978 //                     Memory Instruction Implementations
979 //===----------------------------------------------------------------------===//
980 
visitAllocaInst(AllocaInst & I)981 void Interpreter::visitAllocaInst(AllocaInst &I) {
982   ExecutionContext &SF = ECStack.back();
983 
984   Type *Ty = I.getAllocatedType(); // Type to be allocated
985 
986   // Get the number of elements being allocated by the array...
987   unsigned NumElements =
988     getOperandValue(I.getOperand(0), SF).IntVal.getZExtValue();
989 
990   unsigned TypeSize = (size_t)getDataLayout().getTypeAllocSize(Ty);
991 
992   // Avoid malloc-ing zero bytes, use max()...
993   unsigned MemToAlloc = std::max(1U, NumElements * TypeSize);
994 
995   // Allocate enough memory to hold the type...
996   void *Memory = safe_malloc(MemToAlloc);
997 
998   LLVM_DEBUG(dbgs() << "Allocated Type: " << *Ty << " (" << TypeSize
999                     << " bytes) x " << NumElements << " (Total: " << MemToAlloc
1000                     << ") at " << uintptr_t(Memory) << '\n');
1001 
1002   GenericValue Result = PTOGV(Memory);
1003   assert(Result.PointerVal && "Null pointer returned by malloc!");
1004   SetValue(&I, Result, SF);
1005 
1006   if (I.getOpcode() == Instruction::Alloca)
1007     ECStack.back().Allocas.add(Memory);
1008 }
1009 
1010 // getElementOffset - The workhorse for getelementptr.
1011 //
executeGEPOperation(Value * Ptr,gep_type_iterator I,gep_type_iterator E,ExecutionContext & SF)1012 GenericValue Interpreter::executeGEPOperation(Value *Ptr, gep_type_iterator I,
1013                                               gep_type_iterator E,
1014                                               ExecutionContext &SF) {
1015   assert(Ptr->getType()->isPointerTy() &&
1016          "Cannot getElementOffset of a nonpointer type!");
1017 
1018   uint64_t Total = 0;
1019 
1020   for (; I != E; ++I) {
1021     if (StructType *STy = I.getStructTypeOrNull()) {
1022       const StructLayout *SLO = getDataLayout().getStructLayout(STy);
1023 
1024       const ConstantInt *CPU = cast<ConstantInt>(I.getOperand());
1025       unsigned Index = unsigned(CPU->getZExtValue());
1026 
1027       Total += SLO->getElementOffset(Index);
1028     } else {
1029       // Get the index number for the array... which must be long type...
1030       GenericValue IdxGV = getOperandValue(I.getOperand(), SF);
1031 
1032       int64_t Idx;
1033       unsigned BitWidth =
1034         cast<IntegerType>(I.getOperand()->getType())->getBitWidth();
1035       if (BitWidth == 32)
1036         Idx = (int64_t)(int32_t)IdxGV.IntVal.getZExtValue();
1037       else {
1038         assert(BitWidth == 64 && "Invalid index type for getelementptr");
1039         Idx = (int64_t)IdxGV.IntVal.getZExtValue();
1040       }
1041       Total += I.getSequentialElementStride(getDataLayout()) * Idx;
1042     }
1043   }
1044 
1045   GenericValue Result;
1046   Result.PointerVal = ((char*)getOperandValue(Ptr, SF).PointerVal) + Total;
1047   LLVM_DEBUG(dbgs() << "GEP Index " << Total << " bytes.\n");
1048   return Result;
1049 }
1050 
visitGetElementPtrInst(GetElementPtrInst & I)1051 void Interpreter::visitGetElementPtrInst(GetElementPtrInst &I) {
1052   ExecutionContext &SF = ECStack.back();
1053   SetValue(&I, executeGEPOperation(I.getPointerOperand(),
1054                                    gep_type_begin(I), gep_type_end(I), SF), SF);
1055 }
1056 
visitLoadInst(LoadInst & I)1057 void Interpreter::visitLoadInst(LoadInst &I) {
1058   ExecutionContext &SF = ECStack.back();
1059   GenericValue SRC = getOperandValue(I.getPointerOperand(), SF);
1060   GenericValue *Ptr = (GenericValue*)GVTOP(SRC);
1061   GenericValue Result;
1062   LoadValueFromMemory(Result, Ptr, I.getType());
1063   SetValue(&I, Result, SF);
1064   if (I.isVolatile() && PrintVolatile)
1065     dbgs() << "Volatile load " << I;
1066 }
1067 
visitStoreInst(StoreInst & I)1068 void Interpreter::visitStoreInst(StoreInst &I) {
1069   ExecutionContext &SF = ECStack.back();
1070   GenericValue Val = getOperandValue(I.getOperand(0), SF);
1071   GenericValue SRC = getOperandValue(I.getPointerOperand(), SF);
1072   StoreValueToMemory(Val, (GenericValue *)GVTOP(SRC),
1073                      I.getOperand(0)->getType());
1074   if (I.isVolatile() && PrintVolatile)
1075     dbgs() << "Volatile store: " << I;
1076 }
1077 
1078 //===----------------------------------------------------------------------===//
1079 //                 Miscellaneous Instruction Implementations
1080 //===----------------------------------------------------------------------===//
1081 
visitVAStartInst(VAStartInst & I)1082 void Interpreter::visitVAStartInst(VAStartInst &I) {
1083   ExecutionContext &SF = ECStack.back();
1084   GenericValue ArgIndex;
1085   ArgIndex.UIntPairVal.first = ECStack.size() - 1;
1086   ArgIndex.UIntPairVal.second = 0;
1087   SetValue(&I, ArgIndex, SF);
1088 }
1089 
visitVAEndInst(VAEndInst & I)1090 void Interpreter::visitVAEndInst(VAEndInst &I) {
1091   // va_end is a noop for the interpreter
1092 }
1093 
visitVACopyInst(VACopyInst & I)1094 void Interpreter::visitVACopyInst(VACopyInst &I) {
1095   ExecutionContext &SF = ECStack.back();
1096   SetValue(&I, getOperandValue(*I.arg_begin(), SF), SF);
1097 }
1098 
visitIntrinsicInst(IntrinsicInst & I)1099 void Interpreter::visitIntrinsicInst(IntrinsicInst &I) {
1100   ExecutionContext &SF = ECStack.back();
1101 
1102   // If it is an unknown intrinsic function, use the intrinsic lowering
1103   // class to transform it into hopefully tasty LLVM code.
1104   //
1105   BasicBlock::iterator Me(&I);
1106   BasicBlock *Parent = I.getParent();
1107   bool atBegin(Parent->begin() == Me);
1108   if (!atBegin)
1109     --Me;
1110   IL->LowerIntrinsicCall(&I);
1111 
1112   // Restore the CurInst pointer to the first instruction newly inserted, if
1113   // any.
1114   if (atBegin) {
1115     SF.CurInst = Parent->begin();
1116   } else {
1117     SF.CurInst = Me;
1118     ++SF.CurInst;
1119   }
1120 }
1121 
visitCallBase(CallBase & I)1122 void Interpreter::visitCallBase(CallBase &I) {
1123   ExecutionContext &SF = ECStack.back();
1124 
1125   SF.Caller = &I;
1126   std::vector<GenericValue> ArgVals;
1127   const unsigned NumArgs = SF.Caller->arg_size();
1128   ArgVals.reserve(NumArgs);
1129   for (Value *V : SF.Caller->args())
1130     ArgVals.push_back(getOperandValue(V, SF));
1131 
1132   // To handle indirect calls, we must get the pointer value from the argument
1133   // and treat it as a function pointer.
1134   GenericValue SRC = getOperandValue(SF.Caller->getCalledOperand(), SF);
1135   callFunction((Function*)GVTOP(SRC), ArgVals);
1136 }
1137 
1138 // auxiliary function for shift operations
getShiftAmount(uint64_t orgShiftAmount,llvm::APInt valueToShift)1139 static unsigned getShiftAmount(uint64_t orgShiftAmount,
1140                                llvm::APInt valueToShift) {
1141   unsigned valueWidth = valueToShift.getBitWidth();
1142   if (orgShiftAmount < (uint64_t)valueWidth)
1143     return orgShiftAmount;
1144   // according to the llvm documentation, if orgShiftAmount > valueWidth,
1145   // the result is undfeined. but we do shift by this rule:
1146   return (NextPowerOf2(valueWidth-1) - 1) & orgShiftAmount;
1147 }
1148 
1149 
visitShl(BinaryOperator & I)1150 void Interpreter::visitShl(BinaryOperator &I) {
1151   ExecutionContext &SF = ECStack.back();
1152   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1153   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1154   GenericValue Dest;
1155   Type *Ty = I.getType();
1156 
1157   if (Ty->isVectorTy()) {
1158     uint32_t src1Size = uint32_t(Src1.AggregateVal.size());
1159     assert(src1Size == Src2.AggregateVal.size());
1160     for (unsigned i = 0; i < src1Size; i++) {
1161       GenericValue Result;
1162       uint64_t shiftAmount = Src2.AggregateVal[i].IntVal.getZExtValue();
1163       llvm::APInt valueToShift = Src1.AggregateVal[i].IntVal;
1164       Result.IntVal = valueToShift.shl(getShiftAmount(shiftAmount, valueToShift));
1165       Dest.AggregateVal.push_back(Result);
1166     }
1167   } else {
1168     // scalar
1169     uint64_t shiftAmount = Src2.IntVal.getZExtValue();
1170     llvm::APInt valueToShift = Src1.IntVal;
1171     Dest.IntVal = valueToShift.shl(getShiftAmount(shiftAmount, valueToShift));
1172   }
1173 
1174   SetValue(&I, Dest, SF);
1175 }
1176 
visitLShr(BinaryOperator & I)1177 void Interpreter::visitLShr(BinaryOperator &I) {
1178   ExecutionContext &SF = ECStack.back();
1179   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1180   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1181   GenericValue Dest;
1182   Type *Ty = I.getType();
1183 
1184   if (Ty->isVectorTy()) {
1185     uint32_t src1Size = uint32_t(Src1.AggregateVal.size());
1186     assert(src1Size == Src2.AggregateVal.size());
1187     for (unsigned i = 0; i < src1Size; i++) {
1188       GenericValue Result;
1189       uint64_t shiftAmount = Src2.AggregateVal[i].IntVal.getZExtValue();
1190       llvm::APInt valueToShift = Src1.AggregateVal[i].IntVal;
1191       Result.IntVal = valueToShift.lshr(getShiftAmount(shiftAmount, valueToShift));
1192       Dest.AggregateVal.push_back(Result);
1193     }
1194   } else {
1195     // scalar
1196     uint64_t shiftAmount = Src2.IntVal.getZExtValue();
1197     llvm::APInt valueToShift = Src1.IntVal;
1198     Dest.IntVal = valueToShift.lshr(getShiftAmount(shiftAmount, valueToShift));
1199   }
1200 
1201   SetValue(&I, Dest, SF);
1202 }
1203 
visitAShr(BinaryOperator & I)1204 void Interpreter::visitAShr(BinaryOperator &I) {
1205   ExecutionContext &SF = ECStack.back();
1206   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1207   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1208   GenericValue Dest;
1209   Type *Ty = I.getType();
1210 
1211   if (Ty->isVectorTy()) {
1212     size_t src1Size = Src1.AggregateVal.size();
1213     assert(src1Size == Src2.AggregateVal.size());
1214     for (unsigned i = 0; i < src1Size; i++) {
1215       GenericValue Result;
1216       uint64_t shiftAmount = Src2.AggregateVal[i].IntVal.getZExtValue();
1217       llvm::APInt valueToShift = Src1.AggregateVal[i].IntVal;
1218       Result.IntVal = valueToShift.ashr(getShiftAmount(shiftAmount, valueToShift));
1219       Dest.AggregateVal.push_back(Result);
1220     }
1221   } else {
1222     // scalar
1223     uint64_t shiftAmount = Src2.IntVal.getZExtValue();
1224     llvm::APInt valueToShift = Src1.IntVal;
1225     Dest.IntVal = valueToShift.ashr(getShiftAmount(shiftAmount, valueToShift));
1226   }
1227 
1228   SetValue(&I, Dest, SF);
1229 }
1230 
executeTruncInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1231 GenericValue Interpreter::executeTruncInst(Value *SrcVal, Type *DstTy,
1232                                            ExecutionContext &SF) {
1233   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1234   Type *SrcTy = SrcVal->getType();
1235   if (SrcTy->isVectorTy()) {
1236     Type *DstVecTy = DstTy->getScalarType();
1237     unsigned DBitWidth = cast<IntegerType>(DstVecTy)->getBitWidth();
1238     unsigned NumElts = Src.AggregateVal.size();
1239     // the sizes of src and dst vectors must be equal
1240     Dest.AggregateVal.resize(NumElts);
1241     for (unsigned i = 0; i < NumElts; i++)
1242       Dest.AggregateVal[i].IntVal = Src.AggregateVal[i].IntVal.trunc(DBitWidth);
1243   } else {
1244     IntegerType *DITy = cast<IntegerType>(DstTy);
1245     unsigned DBitWidth = DITy->getBitWidth();
1246     Dest.IntVal = Src.IntVal.trunc(DBitWidth);
1247   }
1248   return Dest;
1249 }
1250 
executeSExtInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1251 GenericValue Interpreter::executeSExtInst(Value *SrcVal, Type *DstTy,
1252                                           ExecutionContext &SF) {
1253   Type *SrcTy = SrcVal->getType();
1254   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1255   if (SrcTy->isVectorTy()) {
1256     Type *DstVecTy = DstTy->getScalarType();
1257     unsigned DBitWidth = cast<IntegerType>(DstVecTy)->getBitWidth();
1258     unsigned size = Src.AggregateVal.size();
1259     // the sizes of src and dst vectors must be equal.
1260     Dest.AggregateVal.resize(size);
1261     for (unsigned i = 0; i < size; i++)
1262       Dest.AggregateVal[i].IntVal = Src.AggregateVal[i].IntVal.sext(DBitWidth);
1263   } else {
1264     auto *DITy = cast<IntegerType>(DstTy);
1265     unsigned DBitWidth = DITy->getBitWidth();
1266     Dest.IntVal = Src.IntVal.sext(DBitWidth);
1267   }
1268   return Dest;
1269 }
1270 
executeZExtInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1271 GenericValue Interpreter::executeZExtInst(Value *SrcVal, Type *DstTy,
1272                                           ExecutionContext &SF) {
1273   Type *SrcTy = SrcVal->getType();
1274   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1275   if (SrcTy->isVectorTy()) {
1276     Type *DstVecTy = DstTy->getScalarType();
1277     unsigned DBitWidth = cast<IntegerType>(DstVecTy)->getBitWidth();
1278 
1279     unsigned size = Src.AggregateVal.size();
1280     // the sizes of src and dst vectors must be equal.
1281     Dest.AggregateVal.resize(size);
1282     for (unsigned i = 0; i < size; i++)
1283       Dest.AggregateVal[i].IntVal = Src.AggregateVal[i].IntVal.zext(DBitWidth);
1284   } else {
1285     auto *DITy = cast<IntegerType>(DstTy);
1286     unsigned DBitWidth = DITy->getBitWidth();
1287     Dest.IntVal = Src.IntVal.zext(DBitWidth);
1288   }
1289   return Dest;
1290 }
1291 
executeFPTruncInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1292 GenericValue Interpreter::executeFPTruncInst(Value *SrcVal, Type *DstTy,
1293                                              ExecutionContext &SF) {
1294   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1295 
1296   if (isa<VectorType>(SrcVal->getType())) {
1297     assert(SrcVal->getType()->getScalarType()->isDoubleTy() &&
1298            DstTy->getScalarType()->isFloatTy() &&
1299            "Invalid FPTrunc instruction");
1300 
1301     unsigned size = Src.AggregateVal.size();
1302     // the sizes of src and dst vectors must be equal.
1303     Dest.AggregateVal.resize(size);
1304     for (unsigned i = 0; i < size; i++)
1305       Dest.AggregateVal[i].FloatVal = (float)Src.AggregateVal[i].DoubleVal;
1306   } else {
1307     assert(SrcVal->getType()->isDoubleTy() && DstTy->isFloatTy() &&
1308            "Invalid FPTrunc instruction");
1309     Dest.FloatVal = (float)Src.DoubleVal;
1310   }
1311 
1312   return Dest;
1313 }
1314 
executeFPExtInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1315 GenericValue Interpreter::executeFPExtInst(Value *SrcVal, Type *DstTy,
1316                                            ExecutionContext &SF) {
1317   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1318 
1319   if (isa<VectorType>(SrcVal->getType())) {
1320     assert(SrcVal->getType()->getScalarType()->isFloatTy() &&
1321            DstTy->getScalarType()->isDoubleTy() && "Invalid FPExt instruction");
1322 
1323     unsigned size = Src.AggregateVal.size();
1324     // the sizes of src and dst vectors must be equal.
1325     Dest.AggregateVal.resize(size);
1326     for (unsigned i = 0; i < size; i++)
1327       Dest.AggregateVal[i].DoubleVal = (double)Src.AggregateVal[i].FloatVal;
1328   } else {
1329     assert(SrcVal->getType()->isFloatTy() && DstTy->isDoubleTy() &&
1330            "Invalid FPExt instruction");
1331     Dest.DoubleVal = (double)Src.FloatVal;
1332   }
1333 
1334   return Dest;
1335 }
1336 
executeFPToUIInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1337 GenericValue Interpreter::executeFPToUIInst(Value *SrcVal, Type *DstTy,
1338                                             ExecutionContext &SF) {
1339   Type *SrcTy = SrcVal->getType();
1340   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1341 
1342   if (isa<VectorType>(SrcTy)) {
1343     Type *DstVecTy = DstTy->getScalarType();
1344     Type *SrcVecTy = SrcTy->getScalarType();
1345     uint32_t DBitWidth = cast<IntegerType>(DstVecTy)->getBitWidth();
1346     unsigned size = Src.AggregateVal.size();
1347     // the sizes of src and dst vectors must be equal.
1348     Dest.AggregateVal.resize(size);
1349 
1350     if (SrcVecTy->getTypeID() == Type::FloatTyID) {
1351       assert(SrcVecTy->isFloatingPointTy() && "Invalid FPToUI instruction");
1352       for (unsigned i = 0; i < size; i++)
1353         Dest.AggregateVal[i].IntVal = APIntOps::RoundFloatToAPInt(
1354             Src.AggregateVal[i].FloatVal, DBitWidth);
1355     } else {
1356       for (unsigned i = 0; i < size; i++)
1357         Dest.AggregateVal[i].IntVal = APIntOps::RoundDoubleToAPInt(
1358             Src.AggregateVal[i].DoubleVal, DBitWidth);
1359     }
1360   } else {
1361     // scalar
1362     uint32_t DBitWidth = cast<IntegerType>(DstTy)->getBitWidth();
1363     assert(SrcTy->isFloatingPointTy() && "Invalid FPToUI instruction");
1364 
1365     if (SrcTy->getTypeID() == Type::FloatTyID)
1366       Dest.IntVal = APIntOps::RoundFloatToAPInt(Src.FloatVal, DBitWidth);
1367     else {
1368       Dest.IntVal = APIntOps::RoundDoubleToAPInt(Src.DoubleVal, DBitWidth);
1369     }
1370   }
1371 
1372   return Dest;
1373 }
1374 
executeFPToSIInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1375 GenericValue Interpreter::executeFPToSIInst(Value *SrcVal, Type *DstTy,
1376                                             ExecutionContext &SF) {
1377   Type *SrcTy = SrcVal->getType();
1378   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1379 
1380   if (isa<VectorType>(SrcTy)) {
1381     Type *DstVecTy = DstTy->getScalarType();
1382     Type *SrcVecTy = SrcTy->getScalarType();
1383     uint32_t DBitWidth = cast<IntegerType>(DstVecTy)->getBitWidth();
1384     unsigned size = Src.AggregateVal.size();
1385     // the sizes of src and dst vectors must be equal
1386     Dest.AggregateVal.resize(size);
1387 
1388     if (SrcVecTy->getTypeID() == Type::FloatTyID) {
1389       assert(SrcVecTy->isFloatingPointTy() && "Invalid FPToSI instruction");
1390       for (unsigned i = 0; i < size; i++)
1391         Dest.AggregateVal[i].IntVal = APIntOps::RoundFloatToAPInt(
1392             Src.AggregateVal[i].FloatVal, DBitWidth);
1393     } else {
1394       for (unsigned i = 0; i < size; i++)
1395         Dest.AggregateVal[i].IntVal = APIntOps::RoundDoubleToAPInt(
1396             Src.AggregateVal[i].DoubleVal, DBitWidth);
1397     }
1398   } else {
1399     // scalar
1400     unsigned DBitWidth = cast<IntegerType>(DstTy)->getBitWidth();
1401     assert(SrcTy->isFloatingPointTy() && "Invalid FPToSI instruction");
1402 
1403     if (SrcTy->getTypeID() == Type::FloatTyID)
1404       Dest.IntVal = APIntOps::RoundFloatToAPInt(Src.FloatVal, DBitWidth);
1405     else {
1406       Dest.IntVal = APIntOps::RoundDoubleToAPInt(Src.DoubleVal, DBitWidth);
1407     }
1408   }
1409   return Dest;
1410 }
1411 
executeUIToFPInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1412 GenericValue Interpreter::executeUIToFPInst(Value *SrcVal, Type *DstTy,
1413                                             ExecutionContext &SF) {
1414   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1415 
1416   if (isa<VectorType>(SrcVal->getType())) {
1417     Type *DstVecTy = DstTy->getScalarType();
1418     unsigned size = Src.AggregateVal.size();
1419     // the sizes of src and dst vectors must be equal
1420     Dest.AggregateVal.resize(size);
1421 
1422     if (DstVecTy->getTypeID() == Type::FloatTyID) {
1423       assert(DstVecTy->isFloatingPointTy() && "Invalid UIToFP instruction");
1424       for (unsigned i = 0; i < size; i++)
1425         Dest.AggregateVal[i].FloatVal =
1426             APIntOps::RoundAPIntToFloat(Src.AggregateVal[i].IntVal);
1427     } else {
1428       for (unsigned i = 0; i < size; i++)
1429         Dest.AggregateVal[i].DoubleVal =
1430             APIntOps::RoundAPIntToDouble(Src.AggregateVal[i].IntVal);
1431     }
1432   } else {
1433     // scalar
1434     assert(DstTy->isFloatingPointTy() && "Invalid UIToFP instruction");
1435     if (DstTy->getTypeID() == Type::FloatTyID)
1436       Dest.FloatVal = APIntOps::RoundAPIntToFloat(Src.IntVal);
1437     else {
1438       Dest.DoubleVal = APIntOps::RoundAPIntToDouble(Src.IntVal);
1439     }
1440   }
1441   return Dest;
1442 }
1443 
executeSIToFPInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1444 GenericValue Interpreter::executeSIToFPInst(Value *SrcVal, Type *DstTy,
1445                                             ExecutionContext &SF) {
1446   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1447 
1448   if (isa<VectorType>(SrcVal->getType())) {
1449     Type *DstVecTy = DstTy->getScalarType();
1450     unsigned size = Src.AggregateVal.size();
1451     // the sizes of src and dst vectors must be equal
1452     Dest.AggregateVal.resize(size);
1453 
1454     if (DstVecTy->getTypeID() == Type::FloatTyID) {
1455       assert(DstVecTy->isFloatingPointTy() && "Invalid SIToFP instruction");
1456       for (unsigned i = 0; i < size; i++)
1457         Dest.AggregateVal[i].FloatVal =
1458             APIntOps::RoundSignedAPIntToFloat(Src.AggregateVal[i].IntVal);
1459     } else {
1460       for (unsigned i = 0; i < size; i++)
1461         Dest.AggregateVal[i].DoubleVal =
1462             APIntOps::RoundSignedAPIntToDouble(Src.AggregateVal[i].IntVal);
1463     }
1464   } else {
1465     // scalar
1466     assert(DstTy->isFloatingPointTy() && "Invalid SIToFP instruction");
1467 
1468     if (DstTy->getTypeID() == Type::FloatTyID)
1469       Dest.FloatVal = APIntOps::RoundSignedAPIntToFloat(Src.IntVal);
1470     else {
1471       Dest.DoubleVal = APIntOps::RoundSignedAPIntToDouble(Src.IntVal);
1472     }
1473   }
1474 
1475   return Dest;
1476 }
1477 
executePtrToIntInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1478 GenericValue Interpreter::executePtrToIntInst(Value *SrcVal, Type *DstTy,
1479                                               ExecutionContext &SF) {
1480   uint32_t DBitWidth = cast<IntegerType>(DstTy)->getBitWidth();
1481   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1482   assert(SrcVal->getType()->isPointerTy() && "Invalid PtrToInt instruction");
1483 
1484   Dest.IntVal = APInt(DBitWidth, (intptr_t) Src.PointerVal);
1485   return Dest;
1486 }
1487 
executeIntToPtrInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1488 GenericValue Interpreter::executeIntToPtrInst(Value *SrcVal, Type *DstTy,
1489                                               ExecutionContext &SF) {
1490   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1491   assert(DstTy->isPointerTy() && "Invalid PtrToInt instruction");
1492 
1493   uint32_t PtrSize = getDataLayout().getPointerSizeInBits();
1494   if (PtrSize != Src.IntVal.getBitWidth())
1495     Src.IntVal = Src.IntVal.zextOrTrunc(PtrSize);
1496 
1497   Dest.PointerVal = PointerTy(intptr_t(Src.IntVal.getZExtValue()));
1498   return Dest;
1499 }
1500 
executeBitCastInst(Value * SrcVal,Type * DstTy,ExecutionContext & SF)1501 GenericValue Interpreter::executeBitCastInst(Value *SrcVal, Type *DstTy,
1502                                              ExecutionContext &SF) {
1503 
1504   // This instruction supports bitwise conversion of vectors to integers and
1505   // to vectors of other types (as long as they have the same size)
1506   Type *SrcTy = SrcVal->getType();
1507   GenericValue Dest, Src = getOperandValue(SrcVal, SF);
1508 
1509   if (isa<VectorType>(SrcTy) || isa<VectorType>(DstTy)) {
1510     // vector src bitcast to vector dst or vector src bitcast to scalar dst or
1511     // scalar src bitcast to vector dst
1512     bool isLittleEndian = getDataLayout().isLittleEndian();
1513     GenericValue TempDst, TempSrc, SrcVec;
1514     Type *SrcElemTy;
1515     Type *DstElemTy;
1516     unsigned SrcBitSize;
1517     unsigned DstBitSize;
1518     unsigned SrcNum;
1519     unsigned DstNum;
1520 
1521     if (isa<VectorType>(SrcTy)) {
1522       SrcElemTy = SrcTy->getScalarType();
1523       SrcBitSize = SrcTy->getScalarSizeInBits();
1524       SrcNum = Src.AggregateVal.size();
1525       SrcVec = Src;
1526     } else {
1527       // if src is scalar value, make it vector <1 x type>
1528       SrcElemTy = SrcTy;
1529       SrcBitSize = SrcTy->getPrimitiveSizeInBits();
1530       SrcNum = 1;
1531       SrcVec.AggregateVal.push_back(Src);
1532     }
1533 
1534     if (isa<VectorType>(DstTy)) {
1535       DstElemTy = DstTy->getScalarType();
1536       DstBitSize = DstTy->getScalarSizeInBits();
1537       DstNum = (SrcNum * SrcBitSize) / DstBitSize;
1538     } else {
1539       DstElemTy = DstTy;
1540       DstBitSize = DstTy->getPrimitiveSizeInBits();
1541       DstNum = 1;
1542     }
1543 
1544     if (SrcNum * SrcBitSize != DstNum * DstBitSize)
1545       llvm_unreachable("Invalid BitCast");
1546 
1547     // If src is floating point, cast to integer first.
1548     TempSrc.AggregateVal.resize(SrcNum);
1549     if (SrcElemTy->isFloatTy()) {
1550       for (unsigned i = 0; i < SrcNum; i++)
1551         TempSrc.AggregateVal[i].IntVal =
1552             APInt::floatToBits(SrcVec.AggregateVal[i].FloatVal);
1553 
1554     } else if (SrcElemTy->isDoubleTy()) {
1555       for (unsigned i = 0; i < SrcNum; i++)
1556         TempSrc.AggregateVal[i].IntVal =
1557             APInt::doubleToBits(SrcVec.AggregateVal[i].DoubleVal);
1558     } else if (SrcElemTy->isIntegerTy()) {
1559       for (unsigned i = 0; i < SrcNum; i++)
1560         TempSrc.AggregateVal[i].IntVal = SrcVec.AggregateVal[i].IntVal;
1561     } else {
1562       // Pointers are not allowed as the element type of vector.
1563       llvm_unreachable("Invalid Bitcast");
1564     }
1565 
1566     // now TempSrc is integer type vector
1567     if (DstNum < SrcNum) {
1568       // Example: bitcast <4 x i32> <i32 0, i32 1, i32 2, i32 3> to <2 x i64>
1569       unsigned Ratio = SrcNum / DstNum;
1570       unsigned SrcElt = 0;
1571       for (unsigned i = 0; i < DstNum; i++) {
1572         GenericValue Elt;
1573         Elt.IntVal = 0;
1574         Elt.IntVal = Elt.IntVal.zext(DstBitSize);
1575         unsigned ShiftAmt = isLittleEndian ? 0 : SrcBitSize * (Ratio - 1);
1576         for (unsigned j = 0; j < Ratio; j++) {
1577           APInt Tmp;
1578           Tmp = Tmp.zext(SrcBitSize);
1579           Tmp = TempSrc.AggregateVal[SrcElt++].IntVal;
1580           Tmp = Tmp.zext(DstBitSize);
1581           Tmp <<= ShiftAmt;
1582           ShiftAmt += isLittleEndian ? SrcBitSize : -SrcBitSize;
1583           Elt.IntVal |= Tmp;
1584         }
1585         TempDst.AggregateVal.push_back(Elt);
1586       }
1587     } else {
1588       // Example: bitcast <2 x i64> <i64 0, i64 1> to <4 x i32>
1589       unsigned Ratio = DstNum / SrcNum;
1590       for (unsigned i = 0; i < SrcNum; i++) {
1591         unsigned ShiftAmt = isLittleEndian ? 0 : DstBitSize * (Ratio - 1);
1592         for (unsigned j = 0; j < Ratio; j++) {
1593           GenericValue Elt;
1594           Elt.IntVal = Elt.IntVal.zext(SrcBitSize);
1595           Elt.IntVal = TempSrc.AggregateVal[i].IntVal;
1596           Elt.IntVal.lshrInPlace(ShiftAmt);
1597           // it could be DstBitSize == SrcBitSize, so check it
1598           if (DstBitSize < SrcBitSize)
1599             Elt.IntVal = Elt.IntVal.trunc(DstBitSize);
1600           ShiftAmt += isLittleEndian ? DstBitSize : -DstBitSize;
1601           TempDst.AggregateVal.push_back(Elt);
1602         }
1603       }
1604     }
1605 
1606     // convert result from integer to specified type
1607     if (isa<VectorType>(DstTy)) {
1608       if (DstElemTy->isDoubleTy()) {
1609         Dest.AggregateVal.resize(DstNum);
1610         for (unsigned i = 0; i < DstNum; i++)
1611           Dest.AggregateVal[i].DoubleVal =
1612               TempDst.AggregateVal[i].IntVal.bitsToDouble();
1613       } else if (DstElemTy->isFloatTy()) {
1614         Dest.AggregateVal.resize(DstNum);
1615         for (unsigned i = 0; i < DstNum; i++)
1616           Dest.AggregateVal[i].FloatVal =
1617               TempDst.AggregateVal[i].IntVal.bitsToFloat();
1618       } else {
1619         Dest = TempDst;
1620       }
1621     } else {
1622       if (DstElemTy->isDoubleTy())
1623         Dest.DoubleVal = TempDst.AggregateVal[0].IntVal.bitsToDouble();
1624       else if (DstElemTy->isFloatTy()) {
1625         Dest.FloatVal = TempDst.AggregateVal[0].IntVal.bitsToFloat();
1626       } else {
1627         Dest.IntVal = TempDst.AggregateVal[0].IntVal;
1628       }
1629     }
1630   } else { //  if (isa<VectorType>(SrcTy)) || isa<VectorType>(DstTy))
1631 
1632     // scalar src bitcast to scalar dst
1633     if (DstTy->isPointerTy()) {
1634       assert(SrcTy->isPointerTy() && "Invalid BitCast");
1635       Dest.PointerVal = Src.PointerVal;
1636     } else if (DstTy->isIntegerTy()) {
1637       if (SrcTy->isFloatTy())
1638         Dest.IntVal = APInt::floatToBits(Src.FloatVal);
1639       else if (SrcTy->isDoubleTy()) {
1640         Dest.IntVal = APInt::doubleToBits(Src.DoubleVal);
1641       } else if (SrcTy->isIntegerTy()) {
1642         Dest.IntVal = Src.IntVal;
1643       } else {
1644         llvm_unreachable("Invalid BitCast");
1645       }
1646     } else if (DstTy->isFloatTy()) {
1647       if (SrcTy->isIntegerTy())
1648         Dest.FloatVal = Src.IntVal.bitsToFloat();
1649       else {
1650         Dest.FloatVal = Src.FloatVal;
1651       }
1652     } else if (DstTy->isDoubleTy()) {
1653       if (SrcTy->isIntegerTy())
1654         Dest.DoubleVal = Src.IntVal.bitsToDouble();
1655       else {
1656         Dest.DoubleVal = Src.DoubleVal;
1657       }
1658     } else {
1659       llvm_unreachable("Invalid Bitcast");
1660     }
1661   }
1662 
1663   return Dest;
1664 }
1665 
visitTruncInst(TruncInst & I)1666 void Interpreter::visitTruncInst(TruncInst &I) {
1667   ExecutionContext &SF = ECStack.back();
1668   SetValue(&I, executeTruncInst(I.getOperand(0), I.getType(), SF), SF);
1669 }
1670 
visitSExtInst(SExtInst & I)1671 void Interpreter::visitSExtInst(SExtInst &I) {
1672   ExecutionContext &SF = ECStack.back();
1673   SetValue(&I, executeSExtInst(I.getOperand(0), I.getType(), SF), SF);
1674 }
1675 
visitZExtInst(ZExtInst & I)1676 void Interpreter::visitZExtInst(ZExtInst &I) {
1677   ExecutionContext &SF = ECStack.back();
1678   SetValue(&I, executeZExtInst(I.getOperand(0), I.getType(), SF), SF);
1679 }
1680 
visitFPTruncInst(FPTruncInst & I)1681 void Interpreter::visitFPTruncInst(FPTruncInst &I) {
1682   ExecutionContext &SF = ECStack.back();
1683   SetValue(&I, executeFPTruncInst(I.getOperand(0), I.getType(), SF), SF);
1684 }
1685 
visitFPExtInst(FPExtInst & I)1686 void Interpreter::visitFPExtInst(FPExtInst &I) {
1687   ExecutionContext &SF = ECStack.back();
1688   SetValue(&I, executeFPExtInst(I.getOperand(0), I.getType(), SF), SF);
1689 }
1690 
visitUIToFPInst(UIToFPInst & I)1691 void Interpreter::visitUIToFPInst(UIToFPInst &I) {
1692   ExecutionContext &SF = ECStack.back();
1693   SetValue(&I, executeUIToFPInst(I.getOperand(0), I.getType(), SF), SF);
1694 }
1695 
visitSIToFPInst(SIToFPInst & I)1696 void Interpreter::visitSIToFPInst(SIToFPInst &I) {
1697   ExecutionContext &SF = ECStack.back();
1698   SetValue(&I, executeSIToFPInst(I.getOperand(0), I.getType(), SF), SF);
1699 }
1700 
visitFPToUIInst(FPToUIInst & I)1701 void Interpreter::visitFPToUIInst(FPToUIInst &I) {
1702   ExecutionContext &SF = ECStack.back();
1703   SetValue(&I, executeFPToUIInst(I.getOperand(0), I.getType(), SF), SF);
1704 }
1705 
visitFPToSIInst(FPToSIInst & I)1706 void Interpreter::visitFPToSIInst(FPToSIInst &I) {
1707   ExecutionContext &SF = ECStack.back();
1708   SetValue(&I, executeFPToSIInst(I.getOperand(0), I.getType(), SF), SF);
1709 }
1710 
visitPtrToIntInst(PtrToIntInst & I)1711 void Interpreter::visitPtrToIntInst(PtrToIntInst &I) {
1712   ExecutionContext &SF = ECStack.back();
1713   SetValue(&I, executePtrToIntInst(I.getOperand(0), I.getType(), SF), SF);
1714 }
1715 
visitIntToPtrInst(IntToPtrInst & I)1716 void Interpreter::visitIntToPtrInst(IntToPtrInst &I) {
1717   ExecutionContext &SF = ECStack.back();
1718   SetValue(&I, executeIntToPtrInst(I.getOperand(0), I.getType(), SF), SF);
1719 }
1720 
visitBitCastInst(BitCastInst & I)1721 void Interpreter::visitBitCastInst(BitCastInst &I) {
1722   ExecutionContext &SF = ECStack.back();
1723   SetValue(&I, executeBitCastInst(I.getOperand(0), I.getType(), SF), SF);
1724 }
1725 
1726 #define IMPLEMENT_VAARG(TY) \
1727    case Type::TY##TyID: Dest.TY##Val = Src.TY##Val; break
1728 
visitVAArgInst(VAArgInst & I)1729 void Interpreter::visitVAArgInst(VAArgInst &I) {
1730   ExecutionContext &SF = ECStack.back();
1731 
1732   // Get the incoming valist parameter.  LLI treats the valist as a
1733   // (ec-stack-depth var-arg-index) pair.
1734   GenericValue VAList = getOperandValue(I.getOperand(0), SF);
1735   GenericValue Dest;
1736   GenericValue Src = ECStack[VAList.UIntPairVal.first]
1737                       .VarArgs[VAList.UIntPairVal.second];
1738   Type *Ty = I.getType();
1739   switch (Ty->getTypeID()) {
1740   case Type::IntegerTyID:
1741     Dest.IntVal = Src.IntVal;
1742     break;
1743   IMPLEMENT_VAARG(Pointer);
1744   IMPLEMENT_VAARG(Float);
1745   IMPLEMENT_VAARG(Double);
1746   default:
1747     dbgs() << "Unhandled dest type for vaarg instruction: " << *Ty << "\n";
1748     llvm_unreachable(nullptr);
1749   }
1750 
1751   // Set the Value of this Instruction.
1752   SetValue(&I, Dest, SF);
1753 
1754   // Move the pointer to the next vararg.
1755   ++VAList.UIntPairVal.second;
1756 }
1757 
visitExtractElementInst(ExtractElementInst & I)1758 void Interpreter::visitExtractElementInst(ExtractElementInst &I) {
1759   ExecutionContext &SF = ECStack.back();
1760   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1761   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1762   GenericValue Dest;
1763 
1764   Type *Ty = I.getType();
1765   const unsigned indx = unsigned(Src2.IntVal.getZExtValue());
1766 
1767   if(Src1.AggregateVal.size() > indx) {
1768     switch (Ty->getTypeID()) {
1769     default:
1770       dbgs() << "Unhandled destination type for extractelement instruction: "
1771       << *Ty << "\n";
1772       llvm_unreachable(nullptr);
1773       break;
1774     case Type::IntegerTyID:
1775       Dest.IntVal = Src1.AggregateVal[indx].IntVal;
1776       break;
1777     case Type::FloatTyID:
1778       Dest.FloatVal = Src1.AggregateVal[indx].FloatVal;
1779       break;
1780     case Type::DoubleTyID:
1781       Dest.DoubleVal = Src1.AggregateVal[indx].DoubleVal;
1782       break;
1783     }
1784   } else {
1785     dbgs() << "Invalid index in extractelement instruction\n";
1786   }
1787 
1788   SetValue(&I, Dest, SF);
1789 }
1790 
visitInsertElementInst(InsertElementInst & I)1791 void Interpreter::visitInsertElementInst(InsertElementInst &I) {
1792   ExecutionContext &SF = ECStack.back();
1793   VectorType *Ty = cast<VectorType>(I.getType());
1794 
1795   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1796   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1797   GenericValue Src3 = getOperandValue(I.getOperand(2), SF);
1798   GenericValue Dest;
1799 
1800   Type *TyContained = Ty->getElementType();
1801 
1802   const unsigned indx = unsigned(Src3.IntVal.getZExtValue());
1803   Dest.AggregateVal = Src1.AggregateVal;
1804 
1805   if(Src1.AggregateVal.size() <= indx)
1806       llvm_unreachable("Invalid index in insertelement instruction");
1807   switch (TyContained->getTypeID()) {
1808     default:
1809       llvm_unreachable("Unhandled dest type for insertelement instruction");
1810     case Type::IntegerTyID:
1811       Dest.AggregateVal[indx].IntVal = Src2.IntVal;
1812       break;
1813     case Type::FloatTyID:
1814       Dest.AggregateVal[indx].FloatVal = Src2.FloatVal;
1815       break;
1816     case Type::DoubleTyID:
1817       Dest.AggregateVal[indx].DoubleVal = Src2.DoubleVal;
1818       break;
1819   }
1820   SetValue(&I, Dest, SF);
1821 }
1822 
visitShuffleVectorInst(ShuffleVectorInst & I)1823 void Interpreter::visitShuffleVectorInst(ShuffleVectorInst &I){
1824   ExecutionContext &SF = ECStack.back();
1825 
1826   VectorType *Ty = cast<VectorType>(I.getType());
1827 
1828   GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
1829   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1830   GenericValue Dest;
1831 
1832   // There is no need to check types of src1 and src2, because the compiled
1833   // bytecode can't contain different types for src1 and src2 for a
1834   // shufflevector instruction.
1835 
1836   Type *TyContained = Ty->getElementType();
1837   unsigned src1Size = (unsigned)Src1.AggregateVal.size();
1838   unsigned src2Size = (unsigned)Src2.AggregateVal.size();
1839   unsigned src3Size = I.getShuffleMask().size();
1840 
1841   Dest.AggregateVal.resize(src3Size);
1842 
1843   switch (TyContained->getTypeID()) {
1844     default:
1845       llvm_unreachable("Unhandled dest type for insertelement instruction");
1846       break;
1847     case Type::IntegerTyID:
1848       for( unsigned i=0; i<src3Size; i++) {
1849         unsigned j = std::max(0, I.getMaskValue(i));
1850         if(j < src1Size)
1851           Dest.AggregateVal[i].IntVal = Src1.AggregateVal[j].IntVal;
1852         else if(j < src1Size + src2Size)
1853           Dest.AggregateVal[i].IntVal = Src2.AggregateVal[j-src1Size].IntVal;
1854         else
1855           // The selector may not be greater than sum of lengths of first and
1856           // second operands and llasm should not allow situation like
1857           // %tmp = shufflevector <2 x i32> <i32 3, i32 4>, <2 x i32> undef,
1858           //                      <2 x i32> < i32 0, i32 5 >,
1859           // where i32 5 is invalid, but let it be additional check here:
1860           llvm_unreachable("Invalid mask in shufflevector instruction");
1861       }
1862       break;
1863     case Type::FloatTyID:
1864       for( unsigned i=0; i<src3Size; i++) {
1865         unsigned j = std::max(0, I.getMaskValue(i));
1866         if(j < src1Size)
1867           Dest.AggregateVal[i].FloatVal = Src1.AggregateVal[j].FloatVal;
1868         else if(j < src1Size + src2Size)
1869           Dest.AggregateVal[i].FloatVal = Src2.AggregateVal[j-src1Size].FloatVal;
1870         else
1871           llvm_unreachable("Invalid mask in shufflevector instruction");
1872         }
1873       break;
1874     case Type::DoubleTyID:
1875       for( unsigned i=0; i<src3Size; i++) {
1876         unsigned j = std::max(0, I.getMaskValue(i));
1877         if(j < src1Size)
1878           Dest.AggregateVal[i].DoubleVal = Src1.AggregateVal[j].DoubleVal;
1879         else if(j < src1Size + src2Size)
1880           Dest.AggregateVal[i].DoubleVal =
1881             Src2.AggregateVal[j-src1Size].DoubleVal;
1882         else
1883           llvm_unreachable("Invalid mask in shufflevector instruction");
1884       }
1885       break;
1886   }
1887   SetValue(&I, Dest, SF);
1888 }
1889 
visitExtractValueInst(ExtractValueInst & I)1890 void Interpreter::visitExtractValueInst(ExtractValueInst &I) {
1891   ExecutionContext &SF = ECStack.back();
1892   Value *Agg = I.getAggregateOperand();
1893   GenericValue Dest;
1894   GenericValue Src = getOperandValue(Agg, SF);
1895 
1896   ExtractValueInst::idx_iterator IdxBegin = I.idx_begin();
1897   unsigned Num = I.getNumIndices();
1898   GenericValue *pSrc = &Src;
1899 
1900   for (unsigned i = 0 ; i < Num; ++i) {
1901     pSrc = &pSrc->AggregateVal[*IdxBegin];
1902     ++IdxBegin;
1903   }
1904 
1905   Type *IndexedType = ExtractValueInst::getIndexedType(Agg->getType(), I.getIndices());
1906   switch (IndexedType->getTypeID()) {
1907     default:
1908       llvm_unreachable("Unhandled dest type for extractelement instruction");
1909     break;
1910     case Type::IntegerTyID:
1911       Dest.IntVal = pSrc->IntVal;
1912     break;
1913     case Type::FloatTyID:
1914       Dest.FloatVal = pSrc->FloatVal;
1915     break;
1916     case Type::DoubleTyID:
1917       Dest.DoubleVal = pSrc->DoubleVal;
1918     break;
1919     case Type::ArrayTyID:
1920     case Type::StructTyID:
1921     case Type::FixedVectorTyID:
1922     case Type::ScalableVectorTyID:
1923       Dest.AggregateVal = pSrc->AggregateVal;
1924     break;
1925     case Type::PointerTyID:
1926       Dest.PointerVal = pSrc->PointerVal;
1927     break;
1928   }
1929 
1930   SetValue(&I, Dest, SF);
1931 }
1932 
visitInsertValueInst(InsertValueInst & I)1933 void Interpreter::visitInsertValueInst(InsertValueInst &I) {
1934 
1935   ExecutionContext &SF = ECStack.back();
1936   Value *Agg = I.getAggregateOperand();
1937 
1938   GenericValue Src1 = getOperandValue(Agg, SF);
1939   GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
1940   GenericValue Dest = Src1; // Dest is a slightly changed Src1
1941 
1942   ExtractValueInst::idx_iterator IdxBegin = I.idx_begin();
1943   unsigned Num = I.getNumIndices();
1944 
1945   GenericValue *pDest = &Dest;
1946   for (unsigned i = 0 ; i < Num; ++i) {
1947     pDest = &pDest->AggregateVal[*IdxBegin];
1948     ++IdxBegin;
1949   }
1950   // pDest points to the target value in the Dest now
1951 
1952   Type *IndexedType = ExtractValueInst::getIndexedType(Agg->getType(), I.getIndices());
1953 
1954   switch (IndexedType->getTypeID()) {
1955     default:
1956       llvm_unreachable("Unhandled dest type for insertelement instruction");
1957     break;
1958     case Type::IntegerTyID:
1959       pDest->IntVal = Src2.IntVal;
1960     break;
1961     case Type::FloatTyID:
1962       pDest->FloatVal = Src2.FloatVal;
1963     break;
1964     case Type::DoubleTyID:
1965       pDest->DoubleVal = Src2.DoubleVal;
1966     break;
1967     case Type::ArrayTyID:
1968     case Type::StructTyID:
1969     case Type::FixedVectorTyID:
1970     case Type::ScalableVectorTyID:
1971       pDest->AggregateVal = Src2.AggregateVal;
1972     break;
1973     case Type::PointerTyID:
1974       pDest->PointerVal = Src2.PointerVal;
1975     break;
1976   }
1977 
1978   SetValue(&I, Dest, SF);
1979 }
1980 
getConstantExprValue(ConstantExpr * CE,ExecutionContext & SF)1981 GenericValue Interpreter::getConstantExprValue (ConstantExpr *CE,
1982                                                 ExecutionContext &SF) {
1983   switch (CE->getOpcode()) {
1984   case Instruction::Trunc:
1985       return executeTruncInst(CE->getOperand(0), CE->getType(), SF);
1986   case Instruction::PtrToInt:
1987       return executePtrToIntInst(CE->getOperand(0), CE->getType(), SF);
1988   case Instruction::IntToPtr:
1989       return executeIntToPtrInst(CE->getOperand(0), CE->getType(), SF);
1990   case Instruction::BitCast:
1991       return executeBitCastInst(CE->getOperand(0), CE->getType(), SF);
1992   case Instruction::GetElementPtr:
1993     return executeGEPOperation(CE->getOperand(0), gep_type_begin(CE),
1994                                gep_type_end(CE), SF);
1995     break;
1996   }
1997 
1998   // The cases below here require a GenericValue parameter for the result
1999   // so we initialize one, compute it and then return it.
2000   GenericValue Op0 = getOperandValue(CE->getOperand(0), SF);
2001   GenericValue Op1 = getOperandValue(CE->getOperand(1), SF);
2002   GenericValue Dest;
2003   switch (CE->getOpcode()) {
2004   case Instruction::Add:  Dest.IntVal = Op0.IntVal + Op1.IntVal; break;
2005   case Instruction::Sub:  Dest.IntVal = Op0.IntVal - Op1.IntVal; break;
2006   case Instruction::Mul:  Dest.IntVal = Op0.IntVal * Op1.IntVal; break;
2007   case Instruction::Xor:  Dest.IntVal = Op0.IntVal ^ Op1.IntVal; break;
2008   case Instruction::Shl:
2009     Dest.IntVal = Op0.IntVal.shl(Op1.IntVal.getZExtValue());
2010     break;
2011   default:
2012     dbgs() << "Unhandled ConstantExpr: " << *CE << "\n";
2013     llvm_unreachable("Unhandled ConstantExpr");
2014   }
2015   return Dest;
2016 }
2017 
getOperandValue(Value * V,ExecutionContext & SF)2018 GenericValue Interpreter::getOperandValue(Value *V, ExecutionContext &SF) {
2019   if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
2020     return getConstantExprValue(CE, SF);
2021   } else if (Constant *CPV = dyn_cast<Constant>(V)) {
2022     return getConstantValue(CPV);
2023   } else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
2024     return PTOGV(getPointerToGlobal(GV));
2025   } else {
2026     return SF.Values[V];
2027   }
2028 }
2029 
2030 //===----------------------------------------------------------------------===//
2031 //                        Dispatch and Execution Code
2032 //===----------------------------------------------------------------------===//
2033 
2034 //===----------------------------------------------------------------------===//
2035 // callFunction - Execute the specified function...
2036 //
callFunction(Function * F,ArrayRef<GenericValue> ArgVals)2037 void Interpreter::callFunction(Function *F, ArrayRef<GenericValue> ArgVals) {
2038   assert((ECStack.empty() || !ECStack.back().Caller ||
2039           ECStack.back().Caller->arg_size() == ArgVals.size()) &&
2040          "Incorrect number of arguments passed into function call!");
2041   // Make a new stack frame... and fill it in.
2042   ECStack.emplace_back();
2043   ExecutionContext &StackFrame = ECStack.back();
2044   StackFrame.CurFunction = F;
2045 
2046   // Special handling for external functions.
2047   if (F->isDeclaration()) {
2048     GenericValue Result = callExternalFunction (F, ArgVals);
2049     // Simulate a 'ret' instruction of the appropriate type.
2050     popStackAndReturnValueToCaller (F->getReturnType (), Result);
2051     return;
2052   }
2053 
2054   // Get pointers to first LLVM BB & Instruction in function.
2055   StackFrame.CurBB     = &F->front();
2056   StackFrame.CurInst   = StackFrame.CurBB->begin();
2057 
2058   // Run through the function arguments and initialize their values...
2059   assert((ArgVals.size() == F->arg_size() ||
2060          (ArgVals.size() > F->arg_size() && F->getFunctionType()->isVarArg()))&&
2061          "Invalid number of values passed to function invocation!");
2062 
2063   // Handle non-varargs arguments...
2064   unsigned i = 0;
2065   for (Function::arg_iterator AI = F->arg_begin(), E = F->arg_end();
2066        AI != E; ++AI, ++i)
2067     SetValue(&*AI, ArgVals[i], StackFrame);
2068 
2069   // Handle varargs arguments...
2070   StackFrame.VarArgs.assign(ArgVals.begin()+i, ArgVals.end());
2071 }
2072 
2073 
run()2074 void Interpreter::run() {
2075   while (!ECStack.empty()) {
2076     // Interpret a single instruction & increment the "PC".
2077     ExecutionContext &SF = ECStack.back();  // Current stack frame
2078     Instruction &I = *SF.CurInst++;         // Increment before execute
2079 
2080     // Track the number of dynamic instructions executed.
2081     ++NumDynamicInsts;
2082 
2083     LLVM_DEBUG(dbgs() << "About to interpret: " << I << "\n");
2084     visit(I);   // Dispatch to one of the visit* methods...
2085   }
2086 }
2087