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 "llvm/DerivedTypes.h"
15 #include <map>
16 #include <dlfcn.h>
17 #include <iostream>
18 #include <link.h>
19 #include <math.h>
20 #include <stdio.h>
21 using std::vector;
22 using std::cout;
23 
24 typedef GenericValue (*ExFunc)(FunctionType *, const vector<GenericValue> &);
25 static std::map<const Function *, ExFunc> Functions;
26 static std::map<std::string, ExFunc> FuncNames;
27 
28 static Interpreter *TheInterpreter;
29 
30 // getCurrentExecutablePath() - Return the directory that the lli executable
31 // lives in.
32 //
33 std::string Interpreter::getCurrentExecutablePath() const {
34   Dl_info Info;
35   if (dladdr(&TheInterpreter, &Info) == 0) return "";
36 
37   std::string LinkAddr(Info.dli_fname);
38   unsigned SlashPos = LinkAddr.rfind('/');
39   if (SlashPos != std::string::npos)
40     LinkAddr.resize(SlashPos);    // Trim the executable name off...
41 
42   return LinkAddr;
43 }
44 
45 
46 static char getTypeID(const Type *Ty) {
47   switch (Ty->getPrimitiveID()) {
48   case Type::VoidTyID:    return 'V';
49   case Type::BoolTyID:    return 'o';
50   case Type::UByteTyID:   return 'B';
51   case Type::SByteTyID:   return 'b';
52   case Type::UShortTyID:  return 'S';
53   case Type::ShortTyID:   return 's';
54   case Type::UIntTyID:    return 'I';
55   case Type::IntTyID:     return 'i';
56   case Type::ULongTyID:   return 'L';
57   case Type::LongTyID:    return 'l';
58   case Type::FloatTyID:   return 'F';
59   case Type::DoubleTyID:  return 'D';
60   case Type::PointerTyID: return 'P';
61   case Type::FunctionTyID:  return 'M';
62   case Type::StructTyID:  return 'T';
63   case Type::ArrayTyID:   return 'A';
64   case Type::OpaqueTyID:  return 'O';
65   default: return 'U';
66   }
67 }
68 
69 static ExFunc lookupFunction(const Function *M) {
70   // Function not found, look it up... start by figuring out what the
71   // composite function name should be.
72   std::string ExtName = "lle_";
73   const FunctionType *MT = M->getFunctionType();
74   for (unsigned i = 0; const Type *Ty = MT->getContainedType(i); ++i)
75     ExtName += getTypeID(Ty);
76   ExtName += "_" + M->getName();
77 
78   //cout << "Tried: '" << ExtName << "'\n";
79   ExFunc FnPtr = FuncNames[ExtName];
80   if (FnPtr == 0)
81     FnPtr = (ExFunc)dlsym(RTLD_DEFAULT, ExtName.c_str());
82   if (FnPtr == 0)
83     FnPtr = FuncNames["lle_X_"+M->getName()];
84   if (FnPtr == 0)  // Try calling a generic function... if it exists...
85     FnPtr = (ExFunc)dlsym(RTLD_DEFAULT, ("lle_X_"+M->getName()).c_str());
86   if (FnPtr != 0)
87     Functions.insert(std::make_pair(M, FnPtr));  // Cache for later
88   return FnPtr;
89 }
90 
91 GenericValue Interpreter::callExternalMethod(Function *M,
92                                          const vector<GenericValue> &ArgVals) {
93   TheInterpreter = this;
94 
95   // Do a lookup to see if the function is in our cache... this should just be a
96   // defered annotation!
97   std::map<const Function *, ExFunc>::iterator FI = Functions.find(M);
98   ExFunc Fn = (FI == Functions.end()) ? lookupFunction(M) : FI->second;
99   if (Fn == 0) {
100     cout << "Tried to execute an unknown external function: "
101 	 << M->getType()->getDescription() << " " << M->getName() << "\n";
102     return GenericValue();
103   }
104 
105   // TODO: FIXME when types are not const!
106   GenericValue Result = Fn(const_cast<FunctionType*>(M->getFunctionType()),
107                            ArgVals);
108   return Result;
109 }
110 
111 
112 //===----------------------------------------------------------------------===//
113 //  Functions "exported" to the running application...
114 //
115 extern "C" {  // Don't add C++ manglings to llvm mangling :)
116 
117 // Implement void printstr([ubyte {x N}] *)
118 GenericValue lle_VP_printstr(FunctionType *M, const vector<GenericValue> &ArgVal){
119   assert(ArgVal.size() == 1 && "printstr only takes one argument!");
120   cout << (char*)ArgVal[0].PointerVal;
121   return GenericValue();
122 }
123 
124 // Implement 'void print(X)' for every type...
125 GenericValue lle_X_print(FunctionType *M, const vector<GenericValue> &ArgVals) {
126   assert(ArgVals.size() == 1 && "generic print only takes one argument!");
127 
128   Interpreter::print(M->getParamTypes()[0], ArgVals[0]);
129   return GenericValue();
130 }
131 
132 // Implement 'void printVal(X)' for every type...
133 GenericValue lle_X_printVal(FunctionType *M, const vector<GenericValue> &ArgVal) {
134   assert(ArgVal.size() == 1 && "generic print only takes one argument!");
135 
136   // Specialize print([ubyte {x N} ] *) and print(sbyte *)
137   if (PointerType *PTy = dyn_cast<PointerType>(M->getParamTypes()[0].get()))
138     if (PTy->getElementType() == Type::SByteTy ||
139         isa<ArrayType>(PTy->getElementType())) {
140       return lle_VP_printstr(M, ArgVal);
141     }
142 
143   Interpreter::printValue(M->getParamTypes()[0], ArgVal[0]);
144   return GenericValue();
145 }
146 
147 // Implement 'void printString(X)'
148 // Argument must be [ubyte {x N} ] * or sbyte *
149 GenericValue lle_X_printString(FunctionType *M, const vector<GenericValue> &ArgVal) {
150   assert(ArgVal.size() == 1 && "generic print only takes one argument!");
151   return lle_VP_printstr(M, ArgVal);
152 }
153 
154 // Implement 'void print<TYPE>(X)' for each primitive type or pointer type
155 #define PRINT_TYPE_FUNC(TYPENAME,TYPEID) \
156   GenericValue lle_X_print##TYPENAME(FunctionType *M,\
157                                      const vector<GenericValue> &ArgVal) {\
158     assert(ArgVal.size() == 1 && "generic print only takes one argument!");\
159     assert(M->getParamTypes()[0].get()->getPrimitiveID() == Type::TYPEID);\
160     Interpreter::printValue(M->getParamTypes()[0], ArgVal[0]);\
161     return GenericValue();\
162   }
163 
164 PRINT_TYPE_FUNC(SByte,   SByteTyID)
165 PRINT_TYPE_FUNC(UByte,   UByteTyID)
166 PRINT_TYPE_FUNC(Short,   ShortTyID)
167 PRINT_TYPE_FUNC(UShort,  UShortTyID)
168 PRINT_TYPE_FUNC(Int,     IntTyID)
169 PRINT_TYPE_FUNC(UInt,    UIntTyID)
170 PRINT_TYPE_FUNC(Long,    LongTyID)
171 PRINT_TYPE_FUNC(ULong,   ULongTyID)
172 PRINT_TYPE_FUNC(Float,   FloatTyID)
173 PRINT_TYPE_FUNC(Double,  DoubleTyID)
174 PRINT_TYPE_FUNC(Pointer, PointerTyID)
175 
176 
177 // void "putchar"(sbyte)
178 GenericValue lle_Vb_putchar(FunctionType *M, const vector<GenericValue> &Args) {
179   cout << Args[0].SByteVal;
180   return GenericValue();
181 }
182 
183 // int "putchar"(int)
184 GenericValue lle_ii_putchar(FunctionType *M, const vector<GenericValue> &Args) {
185   cout << ((char)Args[0].IntVal) << std::flush;
186   return Args[0];
187 }
188 
189 // void "putchar"(ubyte)
190 GenericValue lle_VB_putchar(FunctionType *M, const vector<GenericValue> &Args) {
191   cout << Args[0].SByteVal << std::flush;
192   return Args[0];
193 }
194 
195 // void "__main"()
196 GenericValue lle_V___main(FunctionType *M, const vector<GenericValue> &Args) {
197   return GenericValue();
198 }
199 
200 // void "exit"(int)
201 GenericValue lle_X_exit(FunctionType *M, const vector<GenericValue> &Args) {
202   TheInterpreter->exitCalled(Args[0]);
203   return GenericValue();
204 }
205 
206 // void *malloc(uint)
207 GenericValue lle_X_malloc(FunctionType *M, const vector<GenericValue> &Args) {
208   assert(Args.size() == 1 && "Malloc expects one argument!");
209   GenericValue GV;
210   GV.PointerVal = (PointerTy)malloc(Args[0].UIntVal);
211   return GV;
212 }
213 
214 // void free(void *)
215 GenericValue lle_X_free(FunctionType *M, const vector<GenericValue> &Args) {
216   assert(Args.size() == 1);
217   free((void*)Args[0].PointerVal);
218   return GenericValue();
219 }
220 
221 // int atoi(char *)
222 GenericValue lle_X_atoi(FunctionType *M, const vector<GenericValue> &Args) {
223   assert(Args.size() == 1);
224   GenericValue GV;
225   GV.IntVal = atoi((char*)Args[0].PointerVal);
226   return GV;
227 }
228 
229 // double pow(double, double)
230 GenericValue lle_X_pow(FunctionType *M, const vector<GenericValue> &Args) {
231   assert(Args.size() == 2);
232   GenericValue GV;
233   GV.DoubleVal = pow(Args[0].DoubleVal, Args[1].DoubleVal);
234   return GV;
235 }
236 
237 // double exp(double)
238 GenericValue lle_X_exp(FunctionType *M, const vector<GenericValue> &Args) {
239   assert(Args.size() == 1);
240   GenericValue GV;
241   GV.DoubleVal = exp(Args[0].DoubleVal);
242   return GV;
243 }
244 
245 // double sqrt(double)
246 GenericValue lle_X_sqrt(FunctionType *M, const vector<GenericValue> &Args) {
247   assert(Args.size() == 1);
248   GenericValue GV;
249   GV.DoubleVal = sqrt(Args[0].DoubleVal);
250   return GV;
251 }
252 
253 // double log(double)
254 GenericValue lle_X_log(FunctionType *M, const vector<GenericValue> &Args) {
255   assert(Args.size() == 1);
256   GenericValue GV;
257   GV.DoubleVal = log(Args[0].DoubleVal);
258   return GV;
259 }
260 
261 // double floor(double)
262 GenericValue lle_X_floor(FunctionType *M, const vector<GenericValue> &Args) {
263   assert(Args.size() == 1);
264   GenericValue GV;
265   GV.DoubleVal = floor(Args[0].DoubleVal);
266   return GV;
267 }
268 
269 // double drand48()
270 GenericValue lle_X_drand48(FunctionType *M, const vector<GenericValue> &Args) {
271   assert(Args.size() == 0);
272   GenericValue GV;
273   GV.DoubleVal = drand48();
274   return GV;
275 }
276 
277 // long lrand48()
278 GenericValue lle_X_lrand48(FunctionType *M, const vector<GenericValue> &Args) {
279   assert(Args.size() == 0);
280   GenericValue GV;
281   GV.IntVal = lrand48();
282   return GV;
283 }
284 
285 // void srand48(long)
286 GenericValue lle_X_srand48(FunctionType *M, const vector<GenericValue> &Args) {
287   assert(Args.size() == 1);
288   srand48(Args[0].IntVal);
289   return GenericValue();
290 }
291 
292 // void srand(uint)
293 GenericValue lle_X_srand(FunctionType *M, const vector<GenericValue> &Args) {
294   assert(Args.size() == 1);
295   srand(Args[0].UIntVal);
296   return GenericValue();
297 }
298 
299 // int sprintf(sbyte *, sbyte *, ...) - a very rough implementation to make
300 // output useful.
301 GenericValue lle_X_sprintf(FunctionType *M, const vector<GenericValue> &Args) {
302   char *OutputBuffer = (char *)Args[0].PointerVal;
303   const char *FmtStr = (const char *)Args[1].PointerVal;
304   unsigned ArgNo = 2;
305 
306   // printf should return # chars printed.  This is completely incorrect, but
307   // close enough for now.
308   GenericValue GV; GV.IntVal = strlen(FmtStr);
309   while (1) {
310     switch (*FmtStr) {
311     case 0: return GV;             // Null terminator...
312     default:                       // Normal nonspecial character
313       sprintf(OutputBuffer++, "%c", *FmtStr++);
314       break;
315     case '\\': {                   // Handle escape codes
316       sprintf(OutputBuffer, "%c%c", *FmtStr, *(FmtStr+1));
317       FmtStr += 2; OutputBuffer += 2;
318       break;
319     }
320     case '%': {                    // Handle format specifiers
321       char FmtBuf[100] = "", Buffer[1000] = "";
322       char *FB = FmtBuf;
323       *FB++ = *FmtStr++;
324       char Last = *FB++ = *FmtStr++;
325       unsigned HowLong = 0;
326       while (Last != 'c' && Last != 'd' && Last != 'i' && Last != 'u' &&
327              Last != 'o' && Last != 'x' && Last != 'X' && Last != 'e' &&
328              Last != 'E' && Last != 'g' && Last != 'G' && Last != 'f' &&
329              Last != 'p' && Last != 's' && Last != '%') {
330         if (Last == 'l' || Last == 'L') HowLong++;  // Keep track of l's
331         Last = *FB++ = *FmtStr++;
332       }
333       *FB = 0;
334 
335       switch (Last) {
336       case '%':
337         sprintf(Buffer, FmtBuf); break;
338       case 'c':
339         sprintf(Buffer, FmtBuf, Args[ArgNo++].IntVal); break;
340       case 'd': case 'i':
341       case 'u': case 'o':
342       case 'x': case 'X':
343         if (HowLong == 2)
344           sprintf(Buffer, FmtBuf, Args[ArgNo++].ULongVal);
345         else
346           sprintf(Buffer, FmtBuf, Args[ArgNo++].IntVal); break;
347       case 'e': case 'E': case 'g': case 'G': case 'f':
348         sprintf(Buffer, FmtBuf, Args[ArgNo++].DoubleVal); break;
349       case 'p':
350         sprintf(Buffer, FmtBuf, (void*)Args[ArgNo++].PointerVal); break;
351       case 's':
352         sprintf(Buffer, FmtBuf, (char*)Args[ArgNo++].PointerVal); break;
353       default:  cout << "<unknown printf code '" << *FmtStr << "'!>";
354         ArgNo++; break;
355       }
356       strcpy(OutputBuffer, Buffer);
357       OutputBuffer += strlen(Buffer);
358       }
359       break;
360     }
361   }
362 }
363 
364 // int printf(sbyte *, ...) - a very rough implementation to make output useful.
365 GenericValue lle_X_printf(FunctionType *M, const vector<GenericValue> &Args) {
366   char Buffer[10000];
367   vector<GenericValue> NewArgs;
368   GenericValue GV; GV.PointerVal = (PointerTy)Buffer;
369   NewArgs.push_back(GV);
370   NewArgs.insert(NewArgs.end(), Args.begin(), Args.end());
371   GV = lle_X_sprintf(M, NewArgs);
372   cout << Buffer;
373   return GV;
374 }
375 
376 // int sscanf(const char *format, ...);
377 GenericValue lle_X_sscanf(FunctionType *M, const vector<GenericValue> &args) {
378   assert(args.size() < 10 && "Only handle up to 10 args to sscanf right now!");
379 
380   const char *Args[10];
381   for (unsigned i = 0; i < args.size(); ++i)
382     Args[i] = (const char*)args[i].PointerVal;
383 
384   GenericValue GV;
385   GV.IntVal = sscanf(Args[0], Args[1], Args[2], Args[3], Args[4],
386                      Args[5], Args[6], Args[7], Args[8], Args[9]);
387   return GV;
388 }
389 
390 
391 // int clock(void) - Profiling implementation
392 GenericValue lle_i_clock(FunctionType *M, const vector<GenericValue> &Args) {
393   extern int clock(void);
394   GenericValue GV; GV.IntVal = clock();
395   return GV;
396 }
397 
398 //===----------------------------------------------------------------------===//
399 // IO Functions...
400 //===----------------------------------------------------------------------===//
401 
402 // FILE *fopen(const char *filename, const char *mode);
403 GenericValue lle_X_fopen(FunctionType *M, const vector<GenericValue> &Args) {
404   assert(Args.size() == 2);
405   GenericValue GV;
406 
407   GV.PointerVal = (PointerTy)fopen((const char *)Args[0].PointerVal,
408                                    (const char *)Args[1].PointerVal);
409   return GV;
410 }
411 
412 // int fclose(FILE *F);
413 GenericValue lle_X_fclose(FunctionType *M, const vector<GenericValue> &Args) {
414   assert(Args.size() == 1);
415   GenericValue GV;
416 
417   GV.IntVal = fclose((FILE *)Args[0].PointerVal);
418   return GV;
419 }
420 
421 // size_t fread(void *ptr, size_t size, size_t nitems, FILE *stream);
422 GenericValue lle_X_fread(FunctionType *M, const vector<GenericValue> &Args) {
423   assert(Args.size() == 4);
424   GenericValue GV;
425 
426   GV.UIntVal = fread((void*)Args[0].PointerVal, Args[1].UIntVal,
427                      Args[2].UIntVal, (FILE*)Args[3].PointerVal);
428   return GV;
429 }
430 
431 // size_t fwrite(const void *ptr, size_t size, size_t nitems, FILE *stream);
432 GenericValue lle_X_fwrite(FunctionType *M, const vector<GenericValue> &Args) {
433   assert(Args.size() == 4);
434   GenericValue GV;
435 
436   GV.UIntVal = fwrite((void*)Args[0].PointerVal, Args[1].UIntVal,
437                       Args[2].UIntVal, (FILE*)Args[3].PointerVal);
438   return GV;
439 }
440 
441 // char *fgets(char *s, int n, FILE *stream);
442 GenericValue lle_X_fgets(FunctionType *M, const vector<GenericValue> &Args) {
443   assert(Args.size() == 3);
444   GenericValue GV;
445 
446   GV.PointerVal = (PointerTy)fgets((char*)Args[0].PointerVal, Args[1].IntVal,
447                                    (FILE*)Args[2].PointerVal);
448   return GV;
449 }
450 
451 // int fflush(FILE *stream);
452 GenericValue lle_X_fflush(FunctionType *M, const vector<GenericValue> &Args) {
453   assert(Args.size() == 1);
454   GenericValue GV;
455 
456   GV.IntVal = fflush((FILE*)Args[0].PointerVal);
457   return GV;
458 }
459 
460 } // End extern "C"
461 
462 
463 void Interpreter::initializeExternalMethods() {
464   FuncNames["lle_VP_printstr"] = lle_VP_printstr;
465   FuncNames["lle_X_print"] = lle_X_print;
466   FuncNames["lle_X_printVal"] = lle_X_printVal;
467   FuncNames["lle_X_printString"] = lle_X_printString;
468   FuncNames["lle_X_printUByte"] = lle_X_printUByte;
469   FuncNames["lle_X_printSByte"] = lle_X_printSByte;
470   FuncNames["lle_X_printUShort"] = lle_X_printUShort;
471   FuncNames["lle_X_printShort"] = lle_X_printShort;
472   FuncNames["lle_X_printInt"] = lle_X_printInt;
473   FuncNames["lle_X_printUInt"] = lle_X_printUInt;
474   FuncNames["lle_X_printLong"] = lle_X_printLong;
475   FuncNames["lle_X_printULong"] = lle_X_printULong;
476   FuncNames["lle_X_printFloat"] = lle_X_printFloat;
477   FuncNames["lle_X_printDouble"] = lle_X_printDouble;
478   FuncNames["lle_X_printPointer"] = lle_X_printPointer;
479   FuncNames["lle_Vb_putchar"]     = lle_Vb_putchar;
480   FuncNames["lle_ii_putchar"]     = lle_ii_putchar;
481   FuncNames["lle_VB_putchar"]     = lle_VB_putchar;
482   FuncNames["lle_V___main"]       = lle_V___main;
483   FuncNames["lle_X_exit"]         = lle_X_exit;
484   FuncNames["lle_X_malloc"]       = lle_X_malloc;
485   FuncNames["lle_X_free"]         = lle_X_free;
486   FuncNames["lle_X_atoi"]         = lle_X_atoi;
487   FuncNames["lle_X_pow"]          = lle_X_pow;
488   FuncNames["lle_X_exp"]          = lle_X_exp;
489   FuncNames["lle_X_log"]          = lle_X_log;
490   FuncNames["lle_X_floor"]        = lle_X_floor;
491   FuncNames["lle_X_srand"]        = lle_X_srand;
492   FuncNames["lle_X_drand48"]      = lle_X_drand48;
493   FuncNames["lle_X_srand48"]      = lle_X_srand48;
494   FuncNames["lle_X_lrand48"]      = lle_X_lrand48;
495   FuncNames["lle_X_sqrt"]         = lle_X_sqrt;
496   FuncNames["lle_X_printf"]       = lle_X_printf;
497   FuncNames["lle_X_sprintf"]      = lle_X_sprintf;
498   FuncNames["lle_X_sscanf"]       = lle_X_sscanf;
499   FuncNames["lle_i_clock"]        = lle_i_clock;
500   FuncNames["lle_X_fopen"]        = lle_X_fopen;
501   FuncNames["lle_X_fclose"]       = lle_X_fclose;
502   FuncNames["lle_X_fread"]        = lle_X_fread;
503   FuncNames["lle_X_fwrite"]       = lle_X_fwrite;
504   FuncNames["lle_X_fgets"]        = lle_X_fgets;
505   FuncNames["lle_X_fflush"]       = lle_X_fflush;
506 }
507