1 Compiler-RT 2 ================================ 3 4 This directory and its subdirectories contain source code for the compiler 5 support routines. 6 7 Compiler-RT is open source software. You may freely distribute it under the 8 terms of the license agreement found in LICENSE.txt. 9 10 ================================ 11 12 This is a replacement library for libgcc. Each function is contained 13 in its own file. Each function has a corresponding unit test under 14 test/Unit. 15 16 A rudimentary script to test each file is in the file called 17 test/Unit/test. 18 19 Here is the specification for this library: 20 21 http://gcc.gnu.org/onlinedocs/gccint/Libgcc.html#Libgcc 22 23 Here is a synopsis of the contents of this library: 24 25 typedef int si_int; 26 typedef unsigned su_int; 27 28 typedef long long di_int; 29 typedef unsigned long long du_int; 30 31 // Integral bit manipulation 32 33 di_int __ashldi3(di_int a, si_int b); // a << b 34 ti_int __ashlti3(ti_int a, si_int b); // a << b 35 36 di_int __ashrdi3(di_int a, si_int b); // a >> b arithmetic (sign fill) 37 ti_int __ashrti3(ti_int a, si_int b); // a >> b arithmetic (sign fill) 38 di_int __lshrdi3(di_int a, si_int b); // a >> b logical (zero fill) 39 ti_int __lshrti3(ti_int a, si_int b); // a >> b logical (zero fill) 40 41 si_int __clzsi2(si_int a); // count leading zeros 42 si_int __clzdi2(di_int a); // count leading zeros 43 si_int __clzti2(ti_int a); // count leading zeros 44 si_int __ctzsi2(si_int a); // count trailing zeros 45 si_int __ctzdi2(di_int a); // count trailing zeros 46 si_int __ctzti2(ti_int a); // count trailing zeros 47 48 si_int __ffsdi2(di_int a); // find least significant 1 bit 49 si_int __ffsti2(ti_int a); // find least significant 1 bit 50 51 si_int __paritysi2(si_int a); // bit parity 52 si_int __paritydi2(di_int a); // bit parity 53 si_int __parityti2(ti_int a); // bit parity 54 55 si_int __popcountsi2(si_int a); // bit population 56 si_int __popcountdi2(di_int a); // bit population 57 si_int __popcountti2(ti_int a); // bit population 58 59 uint32_t __bswapsi2(uint32_t a); // a byteswapped, arm only 60 uint64_t __bswapdi2(uint64_t a); // a byteswapped, arm only 61 62 // Integral arithmetic 63 64 di_int __negdi2 (di_int a); // -a 65 ti_int __negti2 (ti_int a); // -a 66 di_int __muldi3 (di_int a, di_int b); // a * b 67 ti_int __multi3 (ti_int a, ti_int b); // a * b 68 si_int __divsi3 (si_int a, si_int b); // a / b signed 69 di_int __divdi3 (di_int a, di_int b); // a / b signed 70 ti_int __divti3 (ti_int a, ti_int b); // a / b signed 71 su_int __udivsi3 (su_int n, su_int d); // a / b unsigned 72 du_int __udivdi3 (du_int a, du_int b); // a / b unsigned 73 tu_int __udivti3 (tu_int a, tu_int b); // a / b unsigned 74 si_int __modsi3 (si_int a, si_int b); // a % b signed 75 di_int __moddi3 (di_int a, di_int b); // a % b signed 76 ti_int __modti3 (ti_int a, ti_int b); // a % b signed 77 su_int __umodsi3 (su_int a, su_int b); // a % b unsigned 78 du_int __umoddi3 (du_int a, du_int b); // a % b unsigned 79 tu_int __umodti3 (tu_int a, tu_int b); // a % b unsigned 80 du_int __udivmoddi4(du_int a, du_int b, du_int* rem); // a / b, *rem = a % b unsigned 81 tu_int __udivmodti4(tu_int a, tu_int b, tu_int* rem); // a / b, *rem = a % b unsigned 82 su_int __udivmodsi4(su_int a, su_int b, su_int* rem); // a / b, *rem = a % b unsigned 83 si_int __divmodsi4(si_int a, si_int b, si_int* rem); // a / b, *rem = a % b signed 84 85 86 87 // Integral arithmetic with trapping overflow 88 89 si_int __absvsi2(si_int a); // abs(a) 90 di_int __absvdi2(di_int a); // abs(a) 91 ti_int __absvti2(ti_int a); // abs(a) 92 93 si_int __negvsi2(si_int a); // -a 94 di_int __negvdi2(di_int a); // -a 95 ti_int __negvti2(ti_int a); // -a 96 97 si_int __addvsi3(si_int a, si_int b); // a + b 98 di_int __addvdi3(di_int a, di_int b); // a + b 99 ti_int __addvti3(ti_int a, ti_int b); // a + b 100 101 si_int __subvsi3(si_int a, si_int b); // a - b 102 di_int __subvdi3(di_int a, di_int b); // a - b 103 ti_int __subvti3(ti_int a, ti_int b); // a - b 104 105 si_int __mulvsi3(si_int a, si_int b); // a * b 106 di_int __mulvdi3(di_int a, di_int b); // a * b 107 ti_int __mulvti3(ti_int a, ti_int b); // a * b 108 109 110 // Integral arithmetic which returns if overflow 111 112 si_int __mulosi4(si_int a, si_int b, int* overflow); // a * b, overflow set to one if result not in signed range 113 di_int __mulodi4(di_int a, di_int b, int* overflow); // a * b, overflow set to one if result not in signed range 114 ti_int __muloti4(ti_int a, ti_int b, int* overflow); // a * b, overflow set to 115 one if result not in signed range 116 117 118 // Integral comparison: a < b -> 0 119 // a == b -> 1 120 // a > b -> 2 121 122 si_int __cmpdi2 (di_int a, di_int b); 123 si_int __cmpti2 (ti_int a, ti_int b); 124 si_int __ucmpdi2(du_int a, du_int b); 125 si_int __ucmpti2(tu_int a, tu_int b); 126 127 // Integral / floating point conversion 128 129 di_int __fixsfdi( float a); 130 di_int __fixdfdi( double a); 131 di_int __fixxfdi(long double a); 132 133 ti_int __fixsfti( float a); 134 ti_int __fixdfti( double a); 135 ti_int __fixxfti(long double a); 136 uint64_t __fixtfdi(long double input); // ppc only, doesn't match documentation 137 138 su_int __fixunssfsi( float a); 139 su_int __fixunsdfsi( double a); 140 su_int __fixunsxfsi(long double a); 141 142 du_int __fixunssfdi( float a); 143 du_int __fixunsdfdi( double a); 144 du_int __fixunsxfdi(long double a); 145 146 tu_int __fixunssfti( float a); 147 tu_int __fixunsdfti( double a); 148 tu_int __fixunsxfti(long double a); 149 uint64_t __fixunstfdi(long double input); // ppc only 150 151 float __floatdisf(di_int a); 152 double __floatdidf(di_int a); 153 long double __floatdixf(di_int a); 154 long double __floatditf(int64_t a); // ppc only 155 156 float __floattisf(ti_int a); 157 double __floattidf(ti_int a); 158 long double __floattixf(ti_int a); 159 160 float __floatundisf(du_int a); 161 double __floatundidf(du_int a); 162 long double __floatundixf(du_int a); 163 long double __floatunditf(uint64_t a); // ppc only 164 165 float __floatuntisf(tu_int a); 166 double __floatuntidf(tu_int a); 167 long double __floatuntixf(tu_int a); 168 169 // Floating point raised to integer power 170 171 float __powisf2( float a, si_int b); // a ^ b 172 double __powidf2( double a, si_int b); // a ^ b 173 long double __powixf2(long double a, si_int b); // a ^ b 174 long double __powitf2(long double a, si_int b); // ppc only, a ^ b 175 176 // Complex arithmetic 177 178 // (a + ib) * (c + id) 179 180 float _Complex __mulsc3( float a, float b, float c, float d); 181 double _Complex __muldc3(double a, double b, double c, double d); 182 long double _Complex __mulxc3(long double a, long double b, 183 long double c, long double d); 184 long double _Complex __multc3(long double a, long double b, 185 long double c, long double d); // ppc only 186 187 // (a + ib) / (c + id) 188 189 float _Complex __divsc3( float a, float b, float c, float d); 190 double _Complex __divdc3(double a, double b, double c, double d); 191 long double _Complex __divxc3(long double a, long double b, 192 long double c, long double d); 193 long double _Complex __divtc3(long double a, long double b, 194 long double c, long double d); // ppc only 195 196 197 // Runtime support 198 199 // __clear_cache() is used to tell process that new instructions have been 200 // written to an address range. Necessary on processors that do not have 201 // a unified instruction and data cache. 202 void __clear_cache(void* start, void* end); 203 204 // __enable_execute_stack() is used with nested functions when a trampoline 205 // function is written onto the stack and that page range needs to be made 206 // executable. 207 void __enable_execute_stack(void* addr); 208 209 // __gcc_personality_v0() is normally only called by the system unwinder. 210 // C code (as opposed to C++) normally does not need a personality function 211 // because there are no catch clauses or destructors to be run. But there 212 // is a C language extension __attribute__((cleanup(func))) which marks local 213 // variables as needing the cleanup function "func" to be run when the 214 // variable goes out of scope. That includes when an exception is thrown, 215 // so a personality handler is needed. 216 _Unwind_Reason_Code __gcc_personality_v0(int version, _Unwind_Action actions, 217 uint64_t exceptionClass, struct _Unwind_Exception* exceptionObject, 218 _Unwind_Context_t context); 219 220 // for use with some implementations of assert() in <assert.h> 221 void __eprintf(const char* format, const char* assertion_expression, 222 const char* line, const char* file); 223 224 // for systems with emulated thread local storage 225 void* __emutls_get_address(struct __emutls_control*); 226 227 228 // Power PC specific functions 229 230 // There is no C interface to the saveFP/restFP functions. They are helper 231 // functions called by the prolog and epilog of functions that need to save 232 // a number of non-volatile float point registers. 233 saveFP 234 restFP 235 236 // PowerPC has a standard template for trampoline functions. This function 237 // generates a custom trampoline function with the specific realFunc 238 // and localsPtr values. 239 void __trampoline_setup(uint32_t* trampOnStack, int trampSizeAllocated, 240 const void* realFunc, void* localsPtr); 241 242 // adds two 128-bit double-double precision values ( x + y ) 243 long double __gcc_qadd(long double x, long double y); 244 245 // subtracts two 128-bit double-double precision values ( x - y ) 246 long double __gcc_qsub(long double x, long double y); 247 248 // multiples two 128-bit double-double precision values ( x * y ) 249 long double __gcc_qmul(long double x, long double y); 250 251 // divides two 128-bit double-double precision values ( x / y ) 252 long double __gcc_qdiv(long double a, long double b); 253 254 255 // ARM specific functions 256 257 // There is no C interface to the switch* functions. These helper functions 258 // are only needed by Thumb1 code for efficient switch table generation. 259 switch16 260 switch32 261 switch8 262 switchu8 263 264 // There is no C interface to the *_vfp_d8_d15_regs functions. There are 265 // called in the prolog and epilog of Thumb1 functions. When the C++ ABI use 266 // SJLJ for exceptions, each function with a catch clause or destuctors needs 267 // to save and restore all registers in it prolog and epliog. But there is 268 // no way to access vector and high float registers from thumb1 code, so the 269 // compiler must add call outs to these helper functions in the prolog and 270 // epilog. 271 restore_vfp_d8_d15_regs 272 save_vfp_d8_d15_regs 273 274 275 // Note: long ago ARM processors did not have floating point hardware support. 276 // Floating point was done in software and floating point parameters were 277 // passed in integer registers. When hardware support was added for floating 278 // point, new *vfp functions were added to do the same operations but with 279 // floating point parameters in floating point registers. 280 281 // Undocumented functions 282 283 float __addsf3vfp(float a, float b); // Appears to return a + b 284 double __adddf3vfp(double a, double b); // Appears to return a + b 285 float __divsf3vfp(float a, float b); // Appears to return a / b 286 double __divdf3vfp(double a, double b); // Appears to return a / b 287 int __eqsf2vfp(float a, float b); // Appears to return one 288 // iff a == b and neither is NaN. 289 int __eqdf2vfp(double a, double b); // Appears to return one 290 // iff a == b and neither is NaN. 291 double __extendsfdf2vfp(float a); // Appears to convert from 292 // float to double. 293 int __fixdfsivfp(double a); // Appears to convert from 294 // double to int. 295 int __fixsfsivfp(float a); // Appears to convert from 296 // float to int. 297 unsigned int __fixunssfsivfp(float a); // Appears to convert from 298 // float to unsigned int. 299 unsigned int __fixunsdfsivfp(double a); // Appears to convert from 300 // double to unsigned int. 301 double __floatsidfvfp(int a); // Appears to convert from 302 // int to double. 303 float __floatsisfvfp(int a); // Appears to convert from 304 // int to float. 305 double __floatunssidfvfp(unsigned int a); // Appears to convert from 306 // unisgned int to double. 307 float __floatunssisfvfp(unsigned int a); // Appears to convert from 308 // unisgned int to float. 309 int __gedf2vfp(double a, double b); // Appears to return __gedf2 310 // (a >= b) 311 int __gesf2vfp(float a, float b); // Appears to return __gesf2 312 // (a >= b) 313 int __gtdf2vfp(double a, double b); // Appears to return __gtdf2 314 // (a > b) 315 int __gtsf2vfp(float a, float b); // Appears to return __gtsf2 316 // (a > b) 317 int __ledf2vfp(double a, double b); // Appears to return __ledf2 318 // (a <= b) 319 int __lesf2vfp(float a, float b); // Appears to return __lesf2 320 // (a <= b) 321 int __ltdf2vfp(double a, double b); // Appears to return __ltdf2 322 // (a < b) 323 int __ltsf2vfp(float a, float b); // Appears to return __ltsf2 324 // (a < b) 325 double __muldf3vfp(double a, double b); // Appears to return a * b 326 float __mulsf3vfp(float a, float b); // Appears to return a * b 327 int __nedf2vfp(double a, double b); // Appears to return __nedf2 328 // (a != b) 329 double __negdf2vfp(double a); // Appears to return -a 330 float __negsf2vfp(float a); // Appears to return -a 331 float __negsf2vfp(float a); // Appears to return -a 332 double __subdf3vfp(double a, double b); // Appears to return a - b 333 float __subsf3vfp(float a, float b); // Appears to return a - b 334 float __truncdfsf2vfp(double a); // Appears to convert from 335 // double to float. 336 int __unorddf2vfp(double a, double b); // Appears to return __unorddf2 337 int __unordsf2vfp(float a, float b); // Appears to return __unordsf2 338 339 340 Preconditions are listed for each function at the definition when there are any. 341 Any preconditions reflect the specification at 342 http://gcc.gnu.org/onlinedocs/gccint/Libgcc.html#Libgcc. 343 344 Assumptions are listed in "int_lib.h", and in individual files. Where possible 345 assumptions are checked at compile time. 346
