/******************************************************************** * * * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE. * * * * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * * * * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002 * * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ * * * ******************************************************************** function: miscellaneous math and prototypes ********************************************************************/ #ifndef _V_RANDOM_H_ #define _V_RANDOM_H_ #include "ivorbiscodec.h" #include "os_types.h" #include "asm_arm.h" #ifndef _V_WIDE_MATH #define _V_WIDE_MATH #ifndef _LOW_ACCURACY_ /* 64 bit multiply */ #include <sys/types.h> #include "config.h" #ifndef WORDS_BIGENDIAN union magic { struct { ogg_int32_t lo; ogg_int32_t hi; } halves; ogg_int64_t whole; }; #else union magic { struct { ogg_int32_t hi; ogg_int32_t lo; } halves; ogg_int64_t whole; }; #endif static inline ogg_int32_t MULT32(ogg_int32_t x, ogg_int32_t y) { union magic magic; magic.whole = (ogg_int64_t)x * y; return magic.halves.hi; } static inline ogg_int32_t MULT31(ogg_int32_t x, ogg_int32_t y) { return MULT32(x,y)<<1; } static inline ogg_int32_t MULT31_SHIFT15(ogg_int32_t x, ogg_int32_t y) { union magic magic; magic.whole = (ogg_int64_t)x * y; return ((ogg_uint32_t)(magic.halves.lo)>>15) | ((magic.halves.hi)<<17); } #else /* 32 bit multiply, more portable but less accurate */ /* * Note: Precision is biased towards the first argument therefore ordering * is important. Shift values were chosen for the best sound quality after * many listening tests. */ /* * For MULT32 and MULT31: The second argument is always a lookup table * value already preshifted from 31 to 8 bits. We therefore take the * opportunity to save on text space and use unsigned char for those * tables in this case. */ static inline ogg_int32_t MULT32(ogg_int32_t x, ogg_int32_t y) { return (x >> 9) * y; /* y preshifted >>23 */ } static inline ogg_int32_t MULT31(ogg_int32_t x, ogg_int32_t y) { return (x >> 8) * y; /* y preshifted >>23 */ } static inline ogg_int32_t MULT31_SHIFT15(ogg_int32_t x, ogg_int32_t y) { return (x >> 6) * y; /* y preshifted >>9 */ } #endif /* * This should be used as a memory barrier, forcing all cached values in * registers to wr writen back to memory. Might or might not be beneficial * depending on the architecture and compiler. */ #define MB() /* * The XPROD functions are meant to optimize the cross products found all * over the place in mdct.c by forcing memory operation ordering to avoid * unnecessary register reloads as soon as memory is being written to. * However this is only beneficial on CPUs with a sane number of general * purpose registers which exclude the Intel x86. On Intel, better let the * compiler actually reload registers directly from original memory by using * macros. */ #ifdef __i386__ #define XPROD32(_a, _b, _t, _v, _x, _y) \ { *(_x)=MULT32(_a,_t)+MULT32(_b,_v); \ *(_y)=MULT32(_b,_t)-MULT32(_a,_v); } #define XPROD31(_a, _b, _t, _v, _x, _y) \ { *(_x)=MULT31(_a,_t)+MULT31(_b,_v); \ *(_y)=MULT31(_b,_t)-MULT31(_a,_v); } #define XNPROD31(_a, _b, _t, _v, _x, _y) \ { *(_x)=MULT31(_a,_t)-MULT31(_b,_v); \ *(_y)=MULT31(_b,_t)+MULT31(_a,_v); } #else static inline void XPROD32(ogg_int32_t a, ogg_int32_t b, ogg_int32_t t, ogg_int32_t v, ogg_int32_t *x, ogg_int32_t *y) { *x = MULT32(a, t) + MULT32(b, v); *y = MULT32(b, t) - MULT32(a, v); } static inline void XPROD31(ogg_int32_t a, ogg_int32_t b, ogg_int32_t t, ogg_int32_t v, ogg_int32_t *x, ogg_int32_t *y) { *x = MULT31(a, t) + MULT31(b, v); *y = MULT31(b, t) - MULT31(a, v); } static inline void XNPROD31(ogg_int32_t a, ogg_int32_t b, ogg_int32_t t, ogg_int32_t v, ogg_int32_t *x, ogg_int32_t *y) { *x = MULT31(a, t) - MULT31(b, v); *y = MULT31(b, t) + MULT31(a, v); } #endif #endif #ifndef _V_CLIP_MATH #define _V_CLIP_MATH static inline ogg_int32_t CLIP_TO_15(ogg_int32_t x) { int ret=x; ret-= ((x<=32767)-1)&(x-32767); ret-= ((x>=-32768)-1)&(x+32768); return(ret); } #endif static inline ogg_int32_t VFLOAT_MULT(ogg_int32_t a,ogg_int32_t ap, ogg_int32_t b,ogg_int32_t bp, ogg_int32_t *p){ if(a && b){ #ifndef _LOW_ACCURACY_ *p=ap+bp+32; return MULT32(a,b); #else *p=ap+bp+31; return (a>>15)*(b>>16); #endif }else return 0; } static inline ogg_int32_t VFLOAT_MULTI(ogg_int32_t a,ogg_int32_t ap, ogg_int32_t i, ogg_int32_t *p){ int ip=_ilog(abs(i))-31; return VFLOAT_MULT(a,ap,i<<-ip,ip,p); } static inline ogg_int32_t VFLOAT_ADD(ogg_int32_t a,ogg_int32_t ap, ogg_int32_t b,ogg_int32_t bp, ogg_int32_t *p){ if(!a){ *p=bp; return b; }else if(!b){ *p=ap; return a; } /* yes, this can leak a bit. */ if(ap>bp){ int shift=ap-bp+1; *p=ap+1; a>>=1; if(shift<32){ b=(b+(1<<(shift-1)))>>shift; }else{ b=0; } }else{ int shift=bp-ap+1; *p=bp+1; b>>=1; if(shift<32){ a=(a+(1<<(shift-1)))>>shift; }else{ a=0; } } a+=b; if((a&0xc0000000)==0xc0000000 || (a&0xc0000000)==0){ a<<=1; (*p)--; } return(a); } #endif