Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================ This is a replacement library for libgcc. Each function is contained in its own file. Each function has a corresponding unit test under test/Unit. A rudimentary script to test each file is in the file called test/Unit/test. Here is the specification for this library: http://gcc.gnu.org/onlinedocs/gccint/Libgcc.html#Libgcc Here is a synopsis of the contents of this library: typedef int si_int; typedef unsigned su_int; typedef long long di_int; typedef unsigned long long du_int; // Integral bit manipulation di_int __ashldi3(di_int a, si_int b); // a << b ti_int __ashlti3(ti_int a, si_int b); // a << b di_int __ashrdi3(di_int a, si_int b); // a >> b arithmetic (sign fill) ti_int __ashrti3(ti_int a, si_int b); // a >> b arithmetic (sign fill) di_int __lshrdi3(di_int a, si_int b); // a >> b logical (zero fill) ti_int __lshrti3(ti_int a, si_int b); // a >> b logical (zero fill) si_int __clzsi2(si_int a); // count leading zeros si_int __clzdi2(di_int a); // count leading zeros si_int __clzti2(ti_int a); // count leading zeros si_int __ctzsi2(si_int a); // count trailing zeros si_int __ctzdi2(di_int a); // count trailing zeros si_int __ctzti2(ti_int a); // count trailing zeros si_int __ffsdi2(di_int a); // find least significant 1 bit si_int __ffsti2(ti_int a); // find least significant 1 bit si_int __paritysi2(si_int a); // bit parity si_int __paritydi2(di_int a); // bit parity si_int __parityti2(ti_int a); // bit parity si_int __popcountsi2(si_int a); // bit population si_int __popcountdi2(di_int a); // bit population si_int __popcountti2(ti_int a); // bit population uint32_t __bswapsi2(uint32_t a); // a byteswapped, arm only uint64_t __bswapdi2(uint64_t a); // a byteswapped, arm only // Integral arithmetic di_int __negdi2 (di_int a); // -a ti_int __negti2 (ti_int a); // -a di_int __muldi3 (di_int a, di_int b); // a * b ti_int __multi3 (ti_int a, ti_int b); // a * b si_int __divsi3 (si_int a, si_int b); // a / b signed di_int __divdi3 (di_int a, di_int b); // a / b signed ti_int __divti3 (ti_int a, ti_int b); // a / b signed su_int __udivsi3 (su_int n, su_int d); // a / b unsigned du_int __udivdi3 (du_int a, du_int b); // a / b unsigned tu_int __udivti3 (tu_int a, tu_int b); // a / b unsigned si_int __modsi3 (si_int a, si_int b); // a % b signed di_int __moddi3 (di_int a, di_int b); // a % b signed ti_int __modti3 (ti_int a, ti_int b); // a % b signed su_int __umodsi3 (su_int a, su_int b); // a % b unsigned du_int __umoddi3 (du_int a, du_int b); // a % b unsigned tu_int __umodti3 (tu_int a, tu_int b); // a % b unsigned du_int __udivmoddi4(du_int a, du_int b, du_int* rem); // a / b, *rem = a % b unsigned tu_int __udivmodti4(tu_int a, tu_int b, tu_int* rem); // a / b, *rem = a % b unsigned su_int __udivmodsi4(su_int a, su_int b, su_int* rem); // a / b, *rem = a % b unsigned si_int __divmodsi4(si_int a, si_int b, si_int* rem); // a / b, *rem = a % b signed // Integral arithmetic with trapping overflow si_int __absvsi2(si_int a); // abs(a) di_int __absvdi2(di_int a); // abs(a) ti_int __absvti2(ti_int a); // abs(a) si_int __negvsi2(si_int a); // -a di_int __negvdi2(di_int a); // -a ti_int __negvti2(ti_int a); // -a si_int __addvsi3(si_int a, si_int b); // a + b di_int __addvdi3(di_int a, di_int b); // a + b ti_int __addvti3(ti_int a, ti_int b); // a + b si_int __subvsi3(si_int a, si_int b); // a - b di_int __subvdi3(di_int a, di_int b); // a - b ti_int __subvti3(ti_int a, ti_int b); // a - b si_int __mulvsi3(si_int a, si_int b); // a * b di_int __mulvdi3(di_int a, di_int b); // a * b ti_int __mulvti3(ti_int a, ti_int b); // a * b // Integral arithmetic which returns if overflow si_int __mulosi4(si_int a, si_int b, int* overflow); // a * b, overflow set to one if result not in signed range di_int __mulodi4(di_int a, di_int b, int* overflow); // a * b, overflow set to one if result not in signed range ti_int __muloti4(ti_int a, ti_int b, int* overflow); // a * b, overflow set to one if result not in signed range // Integral comparison: a < b -> 0 // a == b -> 1 // a > b -> 2 si_int __cmpdi2 (di_int a, di_int b); si_int __cmpti2 (ti_int a, ti_int b); si_int __ucmpdi2(du_int a, du_int b); si_int __ucmpti2(tu_int a, tu_int b); // Integral / floating point conversion di_int __fixsfdi( float a); di_int __fixdfdi( double a); di_int __fixxfdi(long double a); ti_int __fixsfti( float a); ti_int __fixdfti( double a); ti_int __fixxfti(long double a); uint64_t __fixtfdi(long double input); // ppc only, doesn't match documentation su_int __fixunssfsi( float a); su_int __fixunsdfsi( double a); su_int __fixunsxfsi(long double a); du_int __fixunssfdi( float a); du_int __fixunsdfdi( double a); du_int __fixunsxfdi(long double a); tu_int __fixunssfti( float a); tu_int __fixunsdfti( double a); tu_int __fixunsxfti(long double a); uint64_t __fixunstfdi(long double input); // ppc only float __floatdisf(di_int a); double __floatdidf(di_int a); long double __floatdixf(di_int a); long double __floatditf(int64_t a); // ppc only float __floattisf(ti_int a); double __floattidf(ti_int a); long double __floattixf(ti_int a); float __floatundisf(du_int a); double __floatundidf(du_int a); long double __floatundixf(du_int a); long double __floatunditf(uint64_t a); // ppc only float __floatuntisf(tu_int a); double __floatuntidf(tu_int a); long double __floatuntixf(tu_int a); // Floating point raised to integer power float __powisf2( float a, si_int b); // a ^ b double __powidf2( double a, si_int b); // a ^ b long double __powixf2(long double a, si_int b); // a ^ b long double __powitf2(long double a, si_int b); // ppc only, a ^ b // Complex arithmetic // (a + ib) * (c + id) float _Complex __mulsc3( float a, float b, float c, float d); double _Complex __muldc3(double a, double b, double c, double d); long double _Complex __mulxc3(long double a, long double b, long double c, long double d); long double _Complex __multc3(long double a, long double b, long double c, long double d); // ppc only // (a + ib) / (c + id) float _Complex __divsc3( float a, float b, float c, float d); double _Complex __divdc3(double a, double b, double c, double d); long double _Complex __divxc3(long double a, long double b, long double c, long double d); long double _Complex __divtc3(long double a, long double b, long double c, long double d); // ppc only // Runtime support // __clear_cache() is used to tell process that new instructions have been // written to an address range. Necessary on processors that do not have // a unified instuction and data cache. void __clear_cache(void* start, void* end); // __enable_execute_stack() is used with nested functions when a trampoline // function is written onto the stack and that page range needs to be made // executable. void __enable_execute_stack(void* addr); // __gcc_personality_v0() is normally only called by the system unwinder. // C code (as opposed to C++) normally does not need a personality function // because there are no catch clauses or destructors to be run. But there // is a C language extension __attribute__((cleanup(func))) which marks local // variables as needing the cleanup function "func" to be run when the // variable goes out of scope. That includes when an exception is thrown, // so a personality handler is needed. _Unwind_Reason_Code __gcc_personality_v0(int version, _Unwind_Action actions, uint64_t exceptionClass, struct _Unwind_Exception* exceptionObject, _Unwind_Context_t context); // for use with some implementations of assert() in <assert.h> void __eprintf(const char* format, const char* assertion_expression, const char* line, const char* file); // Power PC specific functions // There is no C interface to the saveFP/restFP functions. They are helper // functions called by the prolog and epilog of functions that need to save // a number of non-volatile float point registers. saveFP restFP // PowerPC has a standard template for trampoline functions. This function // generates a custom trampoline function with the specific realFunc // and localsPtr values. void __trampoline_setup(uint32_t* trampOnStack, int trampSizeAllocated, const void* realFunc, void* localsPtr); // adds two 128-bit double-double precision values ( x + y ) long double __gcc_qadd(long double x, long double y); // subtracts two 128-bit double-double precision values ( x - y ) long double __gcc_qsub(long double x, long double y); // multiples two 128-bit double-double precision values ( x * y ) long double __gcc_qmul(long double x, long double y); // divides two 128-bit double-double precision values ( x / y ) long double __gcc_qdiv(long double a, long double b); // ARM specific functions // There is no C interface to the switch* functions. These helper functions // are only needed by Thumb1 code for efficient switch table generation. switch16 switch32 switch8 switchu8 // There is no C interface to the *_vfp_d8_d15_regs functions. There are // called in the prolog and epilog of Thumb1 functions. When the C++ ABI use // SJLJ for exceptions, each function with a catch clause or destuctors needs // to save and restore all registers in it prolog and epliog. But there is // no way to access vector and high float registers from thumb1 code, so the // compiler must add call outs to these helper functions in the prolog and // epilog. restore_vfp_d8_d15_regs save_vfp_d8_d15_regs // Note: long ago ARM processors did not have floating point hardware support. // Floating point was done in software and floating point parameters were // passed in integer registers. When hardware support was added for floating // point, new *vfp functions were added to do the same operations but with // floating point parameters in floating point registers. // Undocumented functions float __addsf3vfp(float a, float b); // Appears to return a + b double __adddf3vfp(double a, double b); // Appears to return a + b float __divsf3vfp(float a, float b); // Appears to return a / b double __divdf3vfp(double a, double b); // Appears to return a / b int __eqsf2vfp(float a, float b); // Appears to return one // iff a == b and neither is NaN. int __eqdf2vfp(double a, double b); // Appears to return one // iff a == b and neither is NaN. double __extendsfdf2vfp(float a); // Appears to convert from // float to double. int __fixdfsivfp(double a); // Appears to convert from // double to int. int __fixsfsivfp(float a); // Appears to convert from // float to int. unsigned int __fixunssfsivfp(float a); // Appears to convert from // float to unsigned int. unsigned int __fixunsdfsivfp(double a); // Appears to convert from // double to unsigned int. double __floatsidfvfp(int a); // Appears to convert from // int to double. float __floatsisfvfp(int a); // Appears to convert from // int to float. double __floatunssidfvfp(unsigned int a); // Appears to convert from // unisgned int to double. float __floatunssisfvfp(unsigned int a); // Appears to convert from // unisgned int to float. int __gedf2vfp(double a, double b); // Appears to return __gedf2 // (a >= b) int __gesf2vfp(float a, float b); // Appears to return __gesf2 // (a >= b) int __gtdf2vfp(double a, double b); // Appears to return __gtdf2 // (a > b) int __gtsf2vfp(float a, float b); // Appears to return __gtsf2 // (a > b) int __ledf2vfp(double a, double b); // Appears to return __ledf2 // (a <= b) int __lesf2vfp(float a, float b); // Appears to return __lesf2 // (a <= b) int __ltdf2vfp(double a, double b); // Appears to return __ltdf2 // (a < b) int __ltsf2vfp(float a, float b); // Appears to return __ltsf2 // (a < b) double __muldf3vfp(double a, double b); // Appears to return a * b float __mulsf3vfp(float a, float b); // Appears to return a * b int __nedf2vfp(double a, double b); // Appears to return __nedf2 // (a != b) double __negdf2vfp(double a); // Appears to return -a float __negsf2vfp(float a); // Appears to return -a float __negsf2vfp(float a); // Appears to return -a double __subdf3vfp(double a, double b); // Appears to return a - b float __subsf3vfp(float a, float b); // Appears to return a - b float __truncdfsf2vfp(double a); // Appears to convert from // double to float. int __unorddf2vfp(double a, double b); // Appears to return __unorddf2 int __unordsf2vfp(float a, float b); // Appears to return __unordsf2 Preconditions are listed for each function at the definition when there are any. Any preconditions reflect the specification at http://gcc.gnu.org/onlinedocs/gccint/Libgcc.html#Libgcc. Assumptions are listed in "int_lib.h", and in individual files. Where possible assumptions are checked at compile time.