#ifndef _avcall_x86_64_c /*-*- C -*-*/ #define _avcall_x86_64_c /** Copyright 1993 Bill Triggs, Copyright 1995-1999, 2004 Bruno Haible, This is free software distributed under the GNU General Public Licence described in the file COPYING. Contact the author if you don't have this or can't live with it. There is ABSOLUTELY NO WARRANTY, explicit or implied, on this software. **/ /*---------------------------------------------------------------------- !!! THIS ROUTINE MUST BE COMPILED gcc -O -fno-omit-frame-pointer !!! Foreign function interface for a Linux x86_64 (a.k.a. amd64) with gcc. This calls a C function with an argument list built up using macros defined in av_call.h. x86_64 Argument Passing Conventions are documented in http://www.x86-64.org/abi.pdf. Up to six words are passed in integer registers (%rdi, %rsi, %rdx, %rcx, %r8, %r9). Up to 8 float/double arguments are passed in SSE registers (%xmm0..%xmm7). Varargs functions expect an upper bound for the number of SSE register arguments in %al (in the range 0..8). All arguments are passed on the stack with word alignment. Structure args are passed as true structures embedded in the argument stack. Integers are returned in %rax, %rdx. Float/double values are returned in %xmm0, %xmm1. To return a structure, the called function copies the value to space pointed to by its first argument, and all other arguments are shifted down by one. ----------------------------------------------------------------------*/ #include "avcall.h.in" #define RETURN(TYPE,VAL) (*(TYPE*)l->raddr = (TYPE)(VAL)) register __avword iarg1 __asm__("rdi"); register __avword iarg2 __asm__("rsi"); register __avword iarg3 __asm__("rdx"); register __avword iarg4 __asm__("rcx"); register __avword iarg5 __asm__("r8"); register __avword iarg6 __asm__("r9"); register double farg1 __asm__("xmm0"); register double farg2 __asm__("xmm1"); register double farg3 __asm__("xmm2"); register double farg4 __asm__("xmm3"); register double farg5 __asm__("xmm4"); register double farg6 __asm__("xmm5"); register double farg7 __asm__("xmm6"); register double farg8 __asm__("xmm7"); int __builtin_avcall(av_alist* l) { register __avword* sp __asm__("rsp"); /* C names for registers */ register __avword iret __asm__("rax"); register __avword iret2 __asm__("rdx"); register double dret __asm__("xmm0"); __avword* argframe = (sp -= __AV_ALIST_WORDS); /* make room for argument list */ int arglen = l->aptr - l->args; int farglen = l->faptr - l->fargs; __avword i, i2; for (i = 0; i < arglen; i++) /* push function args onto stack */ argframe[i] = l->args[i]; /* put 6 integer args into registers */ iarg1 = l->iargs[0]; iarg2 = l->iargs[1]; iarg3 = l->iargs[2]; iarg4 = l->iargs[3]; iarg5 = l->iargs[4]; iarg6 = l->iargs[5]; /* Call function. It's OK to pass 8 values in SSE registers even if the called function takes less than 8 float/double arguments. Similarly for the integer arguments. */ if (l->rtype == __AVfloat) { *(float*)l->raddr = (*(float(*)())l->func)(farglen > 0 ? l->fargs[0] : 0.0, farglen > 1 ? l->fargs[1] : 0.0, farglen > 2 ? l->fargs[2] : 0.0, farglen > 3 ? l->fargs[3] : 0.0, farglen > 4 ? l->fargs[4] : 0.0, farglen > 5 ? l->fargs[5] : 0.0, farglen > 6 ? l->fargs[6] : 0.0, farglen > 7 ? l->fargs[7] : 0.0); } else if (l->rtype == __AVdouble) { *(double*)l->raddr = (*(double(*)())l->func)(farglen > 0 ? l->fargs[0] : 0.0, farglen > 1 ? l->fargs[1] : 0.0, farglen > 2 ? l->fargs[2] : 0.0, farglen > 3 ? l->fargs[3] : 0.0, farglen > 4 ? l->fargs[4] : 0.0, farglen > 5 ? l->fargs[5] : 0.0, farglen > 6 ? l->fargs[6] : 0.0, farglen > 7 ? l->fargs[7] : 0.0); } else { i = (*l->func)(farglen > 0 ? l->fargs[0] : 0.0, farglen > 1 ? l->fargs[1] : 0.0, farglen > 2 ? l->fargs[2] : 0.0, farglen > 3 ? l->fargs[3] : 0.0, farglen > 4 ? l->fargs[4] : 0.0, farglen > 5 ? l->fargs[5] : 0.0, farglen > 6 ? l->fargs[6] : 0.0, farglen > 7 ? l->fargs[7] : 0.0); i2 = iret2; /* save return value */ if (l->rtype == __AVvoid) { } else if (l->rtype == __AVword) { RETURN(__avword, i); } else if (l->rtype == __AVchar) { RETURN(char, i); } else if (l->rtype == __AVschar) { RETURN(signed char, i); } else if (l->rtype == __AVuchar) { RETURN(unsigned char, i); } else if (l->rtype == __AVshort) { RETURN(short, i); } else if (l->rtype == __AVushort) { RETURN(unsigned short, i); } else if (l->rtype == __AVint) { RETURN(int, i); } else if (l->rtype == __AVuint) { RETURN(unsigned int, i); } else if (l->rtype == __AVlong) { RETURN(long, i); } else if (l->rtype == __AVulong) { RETURN(unsigned long, i); } else if (l->rtype == __AVlonglong) { RETURN(long long, i); } else if (l->rtype == __AVulonglong) { RETURN(unsigned long long, i); } else /* see above if (l->rtype == __AVfloat) { } else if (l->rtype == __AVdouble) { } else */ if (l->rtype == __AVvoidp) { RETURN(void*, i); } else if (l->rtype == __AVstruct) { if (l->flags & __AV_PCC_STRUCT_RETURN) { /* pcc struct return convention: need a *(TYPE*)l->raddr = *(TYPE*)i; */ if (l->rsize == sizeof(char)) { RETURN(char, *(char*)i); } else if (l->rsize == sizeof(short)) { RETURN(short, *(short*)i); } else if (l->rsize == sizeof(int)) { RETURN(int, *(int*)i); } else if (l->rsize == sizeof(long)) { RETURN(long, *(long*)i); } else { int n = (l->rsize + sizeof(__avword)-1)/sizeof(__avword); while (--n >= 0) ((__avword*)l->raddr)[n] = ((__avword*)i)[n]; } } else { /* normal struct return convention */ if (l->flags & __AV_REGISTER_STRUCT_RETURN) { if (l->rsize == sizeof(char)) { RETURN(char, i); } else if (l->rsize == sizeof(short)) { RETURN(short, i); } else if (l->rsize == sizeof(int)) { RETURN(int, i); } else if (l->rsize == sizeof(long)) { RETURN(long, i); } else if (l->rsize == 2*sizeof(__avword)) { ((__avword*)l->raddr)[0] = i; ((__avword*)l->raddr)[1] = i2; } } } } } sp += __AV_ALIST_WORDS; return 0; } #endif /*_avcall_x86_64_c */