1 //===-- ExternalFunctions.cpp - Implement External Functions --------------===//
2 //
3 //  This file contains both code to deal with invoking "external" functions, but
4 //  also contains code that implements "exported" external functions.
5 //
6 //  External functions in LLI are implemented by dlopen'ing the lli executable
7 //  and using dlsym to look op the functions that we want to invoke.  If a
8 //  function is found, then the arguments are mangled and passed in to the
9 //  function call.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "Interpreter.h"
14 #include "ExecutionAnnotations.h"
15 #include "llvm/Module.h"
16 #include "llvm/DerivedTypes.h"
17 #include "llvm/SymbolTable.h"
18 #include "llvm/Target/TargetData.h"
19 #include <map>
20 #include "Config/dlfcn.h"
21 #include "Config/link.h"
22 #include <cmath>
23 #include "Config/stdio.h"
24 using std::vector;
25 
26 typedef GenericValue (*ExFunc)(FunctionType *, const vector<GenericValue> &);
27 static std::map<const Function *, ExFunc> Functions;
28 static std::map<std::string, ExFunc> FuncNames;
29 
30 static Interpreter *TheInterpreter;
31 
32 // getCurrentExecutablePath() - Return the directory that the lli executable
33 // lives in.
34 //
35 std::string Interpreter::getCurrentExecutablePath() const {
36   Dl_info Info;
37   if (dladdr(&TheInterpreter, &Info) == 0) return "";
38 
39   std::string LinkAddr(Info.dli_fname);
40   unsigned SlashPos = LinkAddr.rfind('/');
41   if (SlashPos != std::string::npos)
42     LinkAddr.resize(SlashPos);    // Trim the executable name off...
43 
44   return LinkAddr;
45 }
46 
47 
48 static char getTypeID(const Type *Ty) {
49   switch (Ty->getPrimitiveID()) {
50   case Type::VoidTyID:    return 'V';
51   case Type::BoolTyID:    return 'o';
52   case Type::UByteTyID:   return 'B';
53   case Type::SByteTyID:   return 'b';
54   case Type::UShortTyID:  return 'S';
55   case Type::ShortTyID:   return 's';
56   case Type::UIntTyID:    return 'I';
57   case Type::IntTyID:     return 'i';
58   case Type::ULongTyID:   return 'L';
59   case Type::LongTyID:    return 'l';
60   case Type::FloatTyID:   return 'F';
61   case Type::DoubleTyID:  return 'D';
62   case Type::PointerTyID: return 'P';
63   case Type::FunctionTyID:  return 'M';
64   case Type::StructTyID:  return 'T';
65   case Type::ArrayTyID:   return 'A';
66   case Type::OpaqueTyID:  return 'O';
67   default: return 'U';
68   }
69 }
70 
71 static ExFunc lookupFunction(const Function *M) {
72   // Function not found, look it up... start by figuring out what the
73   // composite function name should be.
74   std::string ExtName = "lle_";
75   const FunctionType *MT = M->getFunctionType();
76   for (unsigned i = 0; const Type *Ty = MT->getContainedType(i); ++i)
77     ExtName += getTypeID(Ty);
78   ExtName += "_" + M->getName();
79 
80   //std::cout << "Tried: '" << ExtName << "'\n";
81   ExFunc FnPtr = FuncNames[ExtName];
82   if (FnPtr == 0)
83     FnPtr = (ExFunc)dlsym(RTLD_DEFAULT, ExtName.c_str());
84   if (FnPtr == 0)
85     FnPtr = FuncNames["lle_X_"+M->getName()];
86   if (FnPtr == 0)  // Try calling a generic function... if it exists...
87     FnPtr = (ExFunc)dlsym(RTLD_DEFAULT, ("lle_X_"+M->getName()).c_str());
88   if (FnPtr != 0)
89     Functions.insert(std::make_pair(M, FnPtr));  // Cache for later
90   return FnPtr;
91 }
92 
93 GenericValue Interpreter::callExternalFunction(Function *M,
94                                      const std::vector<GenericValue> &ArgVals) {
95   TheInterpreter = this;
96 
97   // Do a lookup to see if the function is in our cache... this should just be a
98   // defered annotation!
99   std::map<const Function *, ExFunc>::iterator FI = Functions.find(M);
100   ExFunc Fn = (FI == Functions.end()) ? lookupFunction(M) : FI->second;
101   if (Fn == 0) {
102     std::cout << "Tried to execute an unknown external function: "
103               << M->getType()->getDescription() << " " << M->getName() << "\n";
104     return GenericValue();
105   }
106 
107   // TODO: FIXME when types are not const!
108   GenericValue Result = Fn(const_cast<FunctionType*>(M->getFunctionType()),
109                            ArgVals);
110   return Result;
111 }
112 
113 
114 //===----------------------------------------------------------------------===//
115 //  Functions "exported" to the running application...
116 //
117 extern "C" {  // Don't add C++ manglings to llvm mangling :)
118 
119 // void putchar(sbyte)
120 GenericValue lle_Vb_putchar(FunctionType *M, const vector<GenericValue> &Args) {
121   std::cout << Args[0].SByteVal;
122   return GenericValue();
123 }
124 
125 // int putchar(int)
126 GenericValue lle_ii_putchar(FunctionType *M, const vector<GenericValue> &Args) {
127   std::cout << ((char)Args[0].IntVal) << std::flush;
128   return Args[0];
129 }
130 
131 // void putchar(ubyte)
132 GenericValue lle_VB_putchar(FunctionType *M, const vector<GenericValue> &Args) {
133   std::cout << Args[0].SByteVal << std::flush;
134   return Args[0];
135 }
136 
137 // void atexit(Function*)
138 GenericValue lle_X_atexit(FunctionType *M, const vector<GenericValue> &Args) {
139   assert(Args.size() == 1);
140   TheInterpreter->addAtExitHandler((Function*)GVTOP(Args[0]));
141   GenericValue GV;
142   GV.IntVal = 0;
143   return GV;
144 }
145 
146 // void exit(int)
147 GenericValue lle_X_exit(FunctionType *M, const vector<GenericValue> &Args) {
148   TheInterpreter->exitCalled(Args[0]);
149   return GenericValue();
150 }
151 
152 // void abort(void)
153 GenericValue lle_X_abort(FunctionType *M, const vector<GenericValue> &Args) {
154   std::cerr << "***PROGRAM ABORTED***!\n";
155   GenericValue GV;
156   GV.IntVal = 1;
157   TheInterpreter->exitCalled(GV);
158   return GenericValue();
159 }
160 
161 // void *malloc(uint)
162 GenericValue lle_X_malloc(FunctionType *M, const vector<GenericValue> &Args) {
163   assert(Args.size() == 1 && "Malloc expects one argument!");
164   return PTOGV(malloc(Args[0].UIntVal));
165 }
166 
167 // void *calloc(uint, uint)
168 GenericValue lle_X_calloc(FunctionType *M, const vector<GenericValue> &Args) {
169   assert(Args.size() == 2 && "calloc expects two arguments!");
170   return PTOGV(calloc(Args[0].UIntVal, Args[1].UIntVal));
171 }
172 
173 // void free(void *)
174 GenericValue lle_X_free(FunctionType *M, const vector<GenericValue> &Args) {
175   assert(Args.size() == 1);
176   free(GVTOP(Args[0]));
177   return GenericValue();
178 }
179 
180 // int atoi(char *)
181 GenericValue lle_X_atoi(FunctionType *M, const vector<GenericValue> &Args) {
182   assert(Args.size() == 1);
183   GenericValue GV;
184   GV.IntVal = atoi((char*)GVTOP(Args[0]));
185   return GV;
186 }
187 
188 // double pow(double, double)
189 GenericValue lle_X_pow(FunctionType *M, const vector<GenericValue> &Args) {
190   assert(Args.size() == 2);
191   GenericValue GV;
192   GV.DoubleVal = pow(Args[0].DoubleVal, Args[1].DoubleVal);
193   return GV;
194 }
195 
196 // double exp(double)
197 GenericValue lle_X_exp(FunctionType *M, const vector<GenericValue> &Args) {
198   assert(Args.size() == 1);
199   GenericValue GV;
200   GV.DoubleVal = exp(Args[0].DoubleVal);
201   return GV;
202 }
203 
204 // double sqrt(double)
205 GenericValue lle_X_sqrt(FunctionType *M, const vector<GenericValue> &Args) {
206   assert(Args.size() == 1);
207   GenericValue GV;
208   GV.DoubleVal = sqrt(Args[0].DoubleVal);
209   return GV;
210 }
211 
212 // double log(double)
213 GenericValue lle_X_log(FunctionType *M, const vector<GenericValue> &Args) {
214   assert(Args.size() == 1);
215   GenericValue GV;
216   GV.DoubleVal = log(Args[0].DoubleVal);
217   return GV;
218 }
219 
220 // double floor(double)
221 GenericValue lle_X_floor(FunctionType *M, const vector<GenericValue> &Args) {
222   assert(Args.size() == 1);
223   GenericValue GV;
224   GV.DoubleVal = floor(Args[0].DoubleVal);
225   return GV;
226 }
227 
228 // double drand48()
229 GenericValue lle_X_drand48(FunctionType *M, const vector<GenericValue> &Args) {
230   assert(Args.size() == 0);
231   GenericValue GV;
232   GV.DoubleVal = drand48();
233   return GV;
234 }
235 
236 // long lrand48()
237 GenericValue lle_X_lrand48(FunctionType *M, const vector<GenericValue> &Args) {
238   assert(Args.size() == 0);
239   GenericValue GV;
240   GV.IntVal = lrand48();
241   return GV;
242 }
243 
244 // void srand48(long)
245 GenericValue lle_X_srand48(FunctionType *M, const vector<GenericValue> &Args) {
246   assert(Args.size() == 1);
247   srand48(Args[0].IntVal);
248   return GenericValue();
249 }
250 
251 // void srand(uint)
252 GenericValue lle_X_srand(FunctionType *M, const vector<GenericValue> &Args) {
253   assert(Args.size() == 1);
254   srand(Args[0].UIntVal);
255   return GenericValue();
256 }
257 
258 // int puts(const char*)
259 GenericValue lle_X_puts(FunctionType *M, const vector<GenericValue> &Args) {
260   assert(Args.size() == 1);
261   GenericValue GV;
262   GV.IntVal = puts((char*)GVTOP(Args[0]));
263   return GV;
264 }
265 
266 // int sprintf(sbyte *, sbyte *, ...) - a very rough implementation to make
267 // output useful.
268 GenericValue lle_X_sprintf(FunctionType *M, const vector<GenericValue> &Args) {
269   char *OutputBuffer = (char *)GVTOP(Args[0]);
270   const char *FmtStr = (const char *)GVTOP(Args[1]);
271   unsigned ArgNo = 2;
272 
273   // printf should return # chars printed.  This is completely incorrect, but
274   // close enough for now.
275   GenericValue GV; GV.IntVal = strlen(FmtStr);
276   while (1) {
277     switch (*FmtStr) {
278     case 0: return GV;             // Null terminator...
279     default:                       // Normal nonspecial character
280       sprintf(OutputBuffer++, "%c", *FmtStr++);
281       break;
282     case '\\': {                   // Handle escape codes
283       sprintf(OutputBuffer, "%c%c", *FmtStr, *(FmtStr+1));
284       FmtStr += 2; OutputBuffer += 2;
285       break;
286     }
287     case '%': {                    // Handle format specifiers
288       char FmtBuf[100] = "", Buffer[1000] = "";
289       char *FB = FmtBuf;
290       *FB++ = *FmtStr++;
291       char Last = *FB++ = *FmtStr++;
292       unsigned HowLong = 0;
293       while (Last != 'c' && Last != 'd' && Last != 'i' && Last != 'u' &&
294              Last != 'o' && Last != 'x' && Last != 'X' && Last != 'e' &&
295              Last != 'E' && Last != 'g' && Last != 'G' && Last != 'f' &&
296              Last != 'p' && Last != 's' && Last != '%') {
297         if (Last == 'l' || Last == 'L') HowLong++;  // Keep track of l's
298         Last = *FB++ = *FmtStr++;
299       }
300       *FB = 0;
301 
302       switch (Last) {
303       case '%':
304         sprintf(Buffer, FmtBuf); break;
305       case 'c':
306         sprintf(Buffer, FmtBuf, Args[ArgNo++].IntVal); break;
307       case 'd': case 'i':
308       case 'u': case 'o':
309       case 'x': case 'X':
310         if (HowLong >= 1) {
311           if (HowLong == 1 && TheInterpreter->getModule().has64BitPointers() &&
312               sizeof(long) < sizeof(long long)) {
313             // Make sure we use %lld with a 64 bit argument because we might be
314             // compiling LLI on a 32 bit compiler.
315             unsigned Size = strlen(FmtBuf);
316             FmtBuf[Size] = FmtBuf[Size-1];
317             FmtBuf[Size+1] = 0;
318             FmtBuf[Size-1] = 'l';
319           }
320           sprintf(Buffer, FmtBuf, Args[ArgNo++].ULongVal);
321         } else
322           sprintf(Buffer, FmtBuf, Args[ArgNo++].IntVal); break;
323       case 'e': case 'E': case 'g': case 'G': case 'f':
324         sprintf(Buffer, FmtBuf, Args[ArgNo++].DoubleVal); break;
325       case 'p':
326         sprintf(Buffer, FmtBuf, (void*)GVTOP(Args[ArgNo++])); break;
327       case 's':
328         sprintf(Buffer, FmtBuf, (char*)GVTOP(Args[ArgNo++])); break;
329       default:  std::cout << "<unknown printf code '" << *FmtStr << "'!>";
330         ArgNo++; break;
331       }
332       strcpy(OutputBuffer, Buffer);
333       OutputBuffer += strlen(Buffer);
334       }
335       break;
336     }
337   }
338 }
339 
340 // int printf(sbyte *, ...) - a very rough implementation to make output useful.
341 GenericValue lle_X_printf(FunctionType *M, const vector<GenericValue> &Args) {
342   char Buffer[10000];
343   vector<GenericValue> NewArgs;
344   NewArgs.push_back(PTOGV(Buffer));
345   NewArgs.insert(NewArgs.end(), Args.begin(), Args.end());
346   GenericValue GV = lle_X_sprintf(M, NewArgs);
347   std::cout << Buffer;
348   return GV;
349 }
350 
351 static void ByteswapSCANFResults(const char *Fmt, void *Arg0, void *Arg1,
352                                  void *Arg2, void *Arg3, void *Arg4, void *Arg5,
353                                  void *Arg6, void *Arg7, void *Arg8) {
354   void *Args[] = { Arg0, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7, Arg8, 0 };
355 
356   // Loop over the format string, munging read values as appropriate (performs
357   // byteswaps as necessary).
358   unsigned ArgNo = 0;
359   while (*Fmt) {
360     if (*Fmt++ == '%') {
361       // Read any flag characters that may be present...
362       bool Suppress = false;
363       bool Half = false;
364       bool Long = false;
365       bool LongLong = false;  // long long or long double
366 
367       while (1) {
368         switch (*Fmt++) {
369         case '*': Suppress = true; break;
370         case 'a': /*Allocate = true;*/ break;  // We don't need to track this
371         case 'h': Half = true; break;
372         case 'l': Long = true; break;
373         case 'q':
374         case 'L': LongLong = true; break;
375         default:
376           if (Fmt[-1] > '9' || Fmt[-1] < '0')   // Ignore field width specs
377             goto Out;
378         }
379       }
380     Out:
381 
382       // Read the conversion character
383       if (!Suppress && Fmt[-1] != '%') { // Nothing to do?
384         unsigned Size = 0;
385         const Type *Ty = 0;
386 
387         switch (Fmt[-1]) {
388         case 'i': case 'o': case 'u': case 'x': case 'X': case 'n': case 'p':
389         case 'd':
390           if (Long || LongLong) {
391             Size = 8; Ty = Type::ULongTy;
392           } else if (Half) {
393             Size = 4; Ty = Type::UShortTy;
394           } else {
395             Size = 4; Ty = Type::UIntTy;
396           }
397           break;
398 
399         case 'e': case 'g': case 'E':
400         case 'f':
401           if (Long || LongLong) {
402             Size = 8; Ty = Type::DoubleTy;
403           } else {
404             Size = 4; Ty = Type::FloatTy;
405           }
406           break;
407 
408         case 's': case 'c': case '[':  // No byteswap needed
409           Size = 1;
410           Ty = Type::SByteTy;
411           break;
412 
413         default: break;
414         }
415 
416         if (Size) {
417           GenericValue GV;
418           void *Arg = Args[ArgNo++];
419           memcpy(&GV, Arg, Size);
420           TheInterpreter->StoreValueToMemory(GV, (GenericValue*)Arg, Ty);
421         }
422       }
423     }
424   }
425 }
426 
427 // int sscanf(const char *format, ...);
428 GenericValue lle_X_sscanf(FunctionType *M, const vector<GenericValue> &args) {
429   assert(args.size() < 10 && "Only handle up to 10 args to sscanf right now!");
430 
431   char *Args[10];
432   for (unsigned i = 0; i < args.size(); ++i)
433     Args[i] = (char*)GVTOP(args[i]);
434 
435   GenericValue GV;
436   GV.IntVal = sscanf(Args[0], Args[1], Args[2], Args[3], Args[4],
437                      Args[5], Args[6], Args[7], Args[8], Args[9]);
438   ByteswapSCANFResults(Args[1], Args[2], Args[3], Args[4],
439                        Args[5], Args[6], Args[7], Args[8], Args[9], 0);
440   return GV;
441 }
442 
443 // int scanf(const char *format, ...);
444 GenericValue lle_X_scanf(FunctionType *M, const vector<GenericValue> &args) {
445   assert(args.size() < 10 && "Only handle up to 10 args to scanf right now!");
446 
447   char *Args[10];
448   for (unsigned i = 0; i < args.size(); ++i)
449     Args[i] = (char*)GVTOP(args[i]);
450 
451   GenericValue GV;
452   GV.IntVal = scanf(Args[0], Args[1], Args[2], Args[3], Args[4],
453                     Args[5], Args[6], Args[7], Args[8], Args[9]);
454   ByteswapSCANFResults(Args[0], Args[1], Args[2], Args[3], Args[4],
455                        Args[5], Args[6], Args[7], Args[8], Args[9]);
456   return GV;
457 }
458 
459 
460 // int clock(void) - Profiling implementation
461 GenericValue lle_i_clock(FunctionType *M, const vector<GenericValue> &Args) {
462   extern int clock(void);
463   GenericValue GV; GV.IntVal = clock();
464   return GV;
465 }
466 
467 
468 //===----------------------------------------------------------------------===//
469 // String Functions...
470 //===----------------------------------------------------------------------===//
471 
472 // int strcmp(const char *S1, const char *S2);
473 GenericValue lle_X_strcmp(FunctionType *M, const vector<GenericValue> &Args) {
474   assert(Args.size() == 2);
475   GenericValue Ret;
476   Ret.IntVal = strcmp((char*)GVTOP(Args[0]), (char*)GVTOP(Args[1]));
477   return Ret;
478 }
479 
480 // char *strcat(char *Dest, const char *src);
481 GenericValue lle_X_strcat(FunctionType *M, const vector<GenericValue> &Args) {
482   assert(Args.size() == 2);
483   return PTOGV(strcat((char*)GVTOP(Args[0]), (char*)GVTOP(Args[1])));
484 }
485 
486 // char *strcpy(char *Dest, const char *src);
487 GenericValue lle_X_strcpy(FunctionType *M, const vector<GenericValue> &Args) {
488   assert(Args.size() == 2);
489   return PTOGV(strcpy((char*)GVTOP(Args[0]), (char*)GVTOP(Args[1])));
490 }
491 
492 // long strlen(const char *src);
493 GenericValue lle_X_strlen(FunctionType *M, const vector<GenericValue> &Args) {
494   assert(Args.size() == 1);
495   GenericValue Ret;
496   Ret.LongVal = strlen((char*)GVTOP(Args[0]));
497   return Ret;
498 }
499 
500 // char *__strdup(const char *src);
501 GenericValue lle_X___strdup(FunctionType *M, const vector<GenericValue> &Args) {
502   assert(Args.size() == 1);
503   return PTOGV(strdup((char*)GVTOP(Args[0])));
504 }
505 
506 // void *memset(void *S, int C, size_t N)
507 GenericValue lle_X_memset(FunctionType *M, const vector<GenericValue> &Args) {
508   assert(Args.size() == 3);
509   return PTOGV(memset(GVTOP(Args[0]), Args[1].IntVal, Args[2].UIntVal));
510 }
511 
512 // void *memcpy(void *Dest, void *src, size_t Size);
513 GenericValue lle_X_memcpy(FunctionType *M, const vector<GenericValue> &Args) {
514   assert(Args.size() == 3);
515   return PTOGV(memcpy((char*)GVTOP(Args[0]), (char*)GVTOP(Args[1]),
516                       Args[2].UIntVal));
517 }
518 
519 //===----------------------------------------------------------------------===//
520 // IO Functions...
521 //===----------------------------------------------------------------------===//
522 
523 // getFILE - Turn a pointer in the host address space into a legit pointer in
524 // the interpreter address space.  For the most part, this is an identity
525 // transformation, but if the program refers to stdio, stderr, stdin then they
526 // have pointers that are relative to the __iob array.  If this is the case,
527 // change the FILE into the REAL stdio stream.
528 //
529 static FILE *getFILE(void *Ptr) {
530   static Module *LastMod = 0;
531   static PointerTy IOBBase = 0;
532   static unsigned FILESize;
533 
534   if (LastMod != &TheInterpreter->getModule()) { // Module change or initialize?
535     Module *M = LastMod = &TheInterpreter->getModule();
536 
537     // Check to see if the currently loaded module contains an __iob symbol...
538     GlobalVariable *IOB = 0;
539     SymbolTable &ST = M->getSymbolTable();
540     for (SymbolTable::iterator I = ST.begin(), E = ST.end(); I != E; ++I) {
541       SymbolTable::VarMap &M = I->second;
542       for (SymbolTable::VarMap::iterator J = M.begin(), E = M.end();
543            J != E; ++J)
544         if (J->first == "__iob")
545           if ((IOB = dyn_cast<GlobalVariable>(J->second)))
546             break;
547       if (IOB) break;
548     }
549 
550 #if 0   /// FIXME!  __iob support for LLI
551     // If we found an __iob symbol now, find out what the actual address it's
552     // held in is...
553     if (IOB) {
554       // Get the address the array lives in...
555       GlobalAddress *Address =
556         (GlobalAddress*)IOB->getOrCreateAnnotation(GlobalAddressAID);
557       IOBBase = (PointerTy)(GenericValue*)Address->Ptr;
558 
559       // Figure out how big each element of the array is...
560       const ArrayType *AT =
561         dyn_cast<ArrayType>(IOB->getType()->getElementType());
562       if (AT)
563         FILESize = TD.getTypeSize(AT->getElementType());
564       else
565         FILESize = 16*8;  // Default size
566     }
567 #endif
568   }
569 
570   // Check to see if this is a reference to __iob...
571   if (IOBBase) {
572     unsigned FDNum = ((unsigned long)Ptr-IOBBase)/FILESize;
573     if (FDNum == 0)
574       return stdin;
575     else if (FDNum == 1)
576       return stdout;
577     else if (FDNum == 2)
578       return stderr;
579   }
580 
581   return (FILE*)Ptr;
582 }
583 
584 
585 // FILE *fopen(const char *filename, const char *mode);
586 GenericValue lle_X_fopen(FunctionType *M, const vector<GenericValue> &Args) {
587   assert(Args.size() == 2);
588   return PTOGV(fopen((const char *)GVTOP(Args[0]),
589 		     (const char *)GVTOP(Args[1])));
590 }
591 
592 // int fclose(FILE *F);
593 GenericValue lle_X_fclose(FunctionType *M, const vector<GenericValue> &Args) {
594   assert(Args.size() == 1);
595   GenericValue GV;
596   GV.IntVal = fclose(getFILE(GVTOP(Args[0])));
597   return GV;
598 }
599 
600 // int feof(FILE *stream);
601 GenericValue lle_X_feof(FunctionType *M, const vector<GenericValue> &Args) {
602   assert(Args.size() == 1);
603   GenericValue GV;
604 
605   GV.IntVal = feof(getFILE(GVTOP(Args[0])));
606   return GV;
607 }
608 
609 // size_t fread(void *ptr, size_t size, size_t nitems, FILE *stream);
610 GenericValue lle_X_fread(FunctionType *M, const vector<GenericValue> &Args) {
611   assert(Args.size() == 4);
612   GenericValue GV;
613 
614   GV.UIntVal = fread((void*)GVTOP(Args[0]), Args[1].UIntVal,
615                      Args[2].UIntVal, getFILE(GVTOP(Args[3])));
616   return GV;
617 }
618 
619 // size_t fwrite(const void *ptr, size_t size, size_t nitems, FILE *stream);
620 GenericValue lle_X_fwrite(FunctionType *M, const vector<GenericValue> &Args) {
621   assert(Args.size() == 4);
622   GenericValue GV;
623 
624   GV.UIntVal = fwrite((void*)GVTOP(Args[0]), Args[1].UIntVal,
625                       Args[2].UIntVal, getFILE(GVTOP(Args[3])));
626   return GV;
627 }
628 
629 // char *fgets(char *s, int n, FILE *stream);
630 GenericValue lle_X_fgets(FunctionType *M, const vector<GenericValue> &Args) {
631   assert(Args.size() == 3);
632   return GVTOP(fgets((char*)GVTOP(Args[0]), Args[1].IntVal,
633 		     getFILE(GVTOP(Args[2]))));
634 }
635 
636 // FILE *freopen(const char *path, const char *mode, FILE *stream);
637 GenericValue lle_X_freopen(FunctionType *M, const vector<GenericValue> &Args) {
638   assert(Args.size() == 3);
639   return PTOGV(freopen((char*)GVTOP(Args[0]), (char*)GVTOP(Args[1]),
640 		       getFILE(GVTOP(Args[2]))));
641 }
642 
643 // int fflush(FILE *stream);
644 GenericValue lle_X_fflush(FunctionType *M, const vector<GenericValue> &Args) {
645   assert(Args.size() == 1);
646   GenericValue GV;
647   GV.IntVal = fflush(getFILE(GVTOP(Args[0])));
648   return GV;
649 }
650 
651 // int getc(FILE *stream);
652 GenericValue lle_X_getc(FunctionType *M, const vector<GenericValue> &Args) {
653   assert(Args.size() == 1);
654   GenericValue GV;
655   GV.IntVal = getc(getFILE(GVTOP(Args[0])));
656   return GV;
657 }
658 
659 // int _IO_getc(FILE *stream);
660 GenericValue lle_X__IO_getc(FunctionType *F, const vector<GenericValue> &Args) {
661   return lle_X_getc(F, Args);
662 }
663 
664 // int fputc(int C, FILE *stream);
665 GenericValue lle_X_fputc(FunctionType *M, const vector<GenericValue> &Args) {
666   assert(Args.size() == 2);
667   GenericValue GV;
668   GV.IntVal = fputc(Args[0].IntVal, getFILE(GVTOP(Args[1])));
669   return GV;
670 }
671 
672 // int ungetc(int C, FILE *stream);
673 GenericValue lle_X_ungetc(FunctionType *M, const vector<GenericValue> &Args) {
674   assert(Args.size() == 2);
675   GenericValue GV;
676   GV.IntVal = ungetc(Args[0].IntVal, getFILE(GVTOP(Args[1])));
677   return GV;
678 }
679 
680 // int fprintf(FILE *,sbyte *, ...) - a very rough implementation to make output
681 // useful.
682 GenericValue lle_X_fprintf(FunctionType *M, const vector<GenericValue> &Args) {
683   assert(Args.size() >= 2);
684   char Buffer[10000];
685   vector<GenericValue> NewArgs;
686   NewArgs.push_back(PTOGV(Buffer));
687   NewArgs.insert(NewArgs.end(), Args.begin()+1, Args.end());
688   GenericValue GV = lle_X_sprintf(M, NewArgs);
689 
690   fputs(Buffer, getFILE(GVTOP(Args[0])));
691   return GV;
692 }
693 
694 //===----------------------------------------------------------------------===//
695 // LLVM Intrinsic Functions...
696 //===----------------------------------------------------------------------===//
697 
698 // void llvm.va_start(<va_list> *) - Implement the va_start operation...
699 GenericValue llvm_va_start(FunctionType *F, const vector<GenericValue> &Args) {
700   assert(Args.size() == 1);
701   GenericValue *VAListP = (GenericValue *)GVTOP(Args[0]);
702   GenericValue Val;
703   Val.UIntVal = 0;   // Start at the first '...' argument...
704   TheInterpreter->StoreValueToMemory(Val, VAListP, Type::UIntTy);
705   return GenericValue();
706 }
707 
708 // void llvm.va_end(<va_list> *) - Implement the va_end operation...
709 GenericValue llvm_va_end(FunctionType *F, const vector<GenericValue> &Args) {
710   assert(Args.size() == 1);
711   return GenericValue();    // Noop!
712 }
713 
714 // void llvm.va_copy(<va_list> *, <va_list>) - Implement the va_copy
715 // operation...
716 GenericValue llvm_va_copy(FunctionType *F, const vector<GenericValue> &Args) {
717   assert(Args.size() == 2);
718   GenericValue *DestVAList = (GenericValue*)GVTOP(Args[0]);
719   TheInterpreter->StoreValueToMemory(Args[1], DestVAList, Type::UIntTy);
720   return GenericValue();
721 }
722 
723 } // End extern "C"
724 
725 
726 void Interpreter::initializeExternalFunctions() {
727   FuncNames["lle_Vb_putchar"]     = lle_Vb_putchar;
728   FuncNames["lle_ii_putchar"]     = lle_ii_putchar;
729   FuncNames["lle_VB_putchar"]     = lle_VB_putchar;
730   FuncNames["lle_X_exit"]         = lle_X_exit;
731   FuncNames["lle_X_abort"]        = lle_X_abort;
732   FuncNames["lle_X_malloc"]       = lle_X_malloc;
733   FuncNames["lle_X_calloc"]       = lle_X_calloc;
734   FuncNames["lle_X_free"]         = lle_X_free;
735   FuncNames["lle_X_atoi"]         = lle_X_atoi;
736   FuncNames["lle_X_pow"]          = lle_X_pow;
737   FuncNames["lle_X_exp"]          = lle_X_exp;
738   FuncNames["lle_X_log"]          = lle_X_log;
739   FuncNames["lle_X_floor"]        = lle_X_floor;
740   FuncNames["lle_X_srand"]        = lle_X_srand;
741   FuncNames["lle_X_drand48"]      = lle_X_drand48;
742   FuncNames["lle_X_srand48"]      = lle_X_srand48;
743   FuncNames["lle_X_lrand48"]      = lle_X_lrand48;
744   FuncNames["lle_X_sqrt"]         = lle_X_sqrt;
745   FuncNames["lle_X_puts"]         = lle_X_puts;
746   FuncNames["lle_X_printf"]       = lle_X_printf;
747   FuncNames["lle_X_sprintf"]      = lle_X_sprintf;
748   FuncNames["lle_X_sscanf"]       = lle_X_sscanf;
749   FuncNames["lle_X_scanf"]        = lle_X_scanf;
750   FuncNames["lle_i_clock"]        = lle_i_clock;
751 
752   FuncNames["lle_X_strcmp"]       = lle_X_strcmp;
753   FuncNames["lle_X_strcat"]       = lle_X_strcat;
754   FuncNames["lle_X_strcpy"]       = lle_X_strcpy;
755   FuncNames["lle_X_strlen"]       = lle_X_strlen;
756   FuncNames["lle_X___strdup"]     = lle_X___strdup;
757   FuncNames["lle_X_memset"]       = lle_X_memset;
758   FuncNames["lle_X_memcpy"]       = lle_X_memcpy;
759 
760   FuncNames["lle_X_fopen"]        = lle_X_fopen;
761   FuncNames["lle_X_fclose"]       = lle_X_fclose;
762   FuncNames["lle_X_feof"]         = lle_X_feof;
763   FuncNames["lle_X_fread"]        = lle_X_fread;
764   FuncNames["lle_X_fwrite"]       = lle_X_fwrite;
765   FuncNames["lle_X_fgets"]        = lle_X_fgets;
766   FuncNames["lle_X_fflush"]       = lle_X_fflush;
767   FuncNames["lle_X_fgetc"]        = lle_X_getc;
768   FuncNames["lle_X_getc"]         = lle_X_getc;
769   FuncNames["lle_X__IO_getc"]     = lle_X__IO_getc;
770   FuncNames["lle_X_fputc"]        = lle_X_fputc;
771   FuncNames["lle_X_ungetc"]       = lle_X_ungetc;
772   FuncNames["lle_X_fprintf"]      = lle_X_fprintf;
773   FuncNames["lle_X_freopen"]      = lle_X_freopen;
774 
775   FuncNames["lle_X_llvm.va_start"]= llvm_va_start;
776   FuncNames["lle_X_llvm.va_end"]  = llvm_va_end;
777   FuncNames["lle_X_llvm.va_copy"] = llvm_va_copy;
778 }
779