From 3d7d4dc9c2f0ce1146d10b77067943950924f1fe Mon Sep 17 00:00:00 2001 From: Christophe Riccio Date: Fri, 6 May 2011 12:12:22 +0100 Subject: [PATCH] Fixed glm::detail::nextafter implementation --- glm/gtx/ulp.inl | 205 ++++++++++++++++++++++++------------------------ 1 file changed, 104 insertions(+), 101 deletions(-) diff --git a/glm/gtx/ulp.inl b/glm/gtx/ulp.inl index b60db3e4..6cc19219 100644 --- a/glm/gtx/ulp.inl +++ b/glm/gtx/ulp.inl @@ -20,8 +20,8 @@ * is preserved. * ==================================================== */ -/* -#define EXTRACT_WORDS(ix0,ix1,d) \ + +#define GLM_EXTRACT_WORDS(ix0,ix1,d) \ do { \ ieee_double_shape_type ew_u; \ ew_u.value = (d); \ @@ -29,21 +29,21 @@ do { \ (ix1) = ew_u.parts.lsw; \ } while (0) -#define GET_FLOAT_WORD(i,d) \ +#define GLM_GET_FLOAT_WORD(i,d) \ do { \ ieee_float_shape_type gf_u; \ gf_u.value = (d); \ (i) = gf_u.word; \ } while (0) -#define SET_FLOAT_WORD(d,i) \ +#define GLM_SET_FLOAT_WORD(d,i) \ do { \ ieee_float_shape_type sf_u; \ sf_u.word = (i); \ (d) = sf_u.value; \ } while (0) -#define INSERT_WORDS(d,ix0,ix1) \ +#define GLM_INSERT_WORDS(d,ix0,ix1) \ do { \ ieee_double_shape_type iw_u; \ iw_u.parts.msw = (ix0); \ @@ -51,113 +51,116 @@ do { \ (d) = iw_u.value; \ } while (0) -float nextafterf(float x, float y) +namespace glm{ +namespace detail { - volatile float t; - int32_t hx,hy,ix,iy; + GLM_FUNC_QUALIFIER float nextafterf(float x, float y) + { + volatile float t; + glm::int32 hx, hy, ix, iy; - GET_FLOAT_WORD(hx,x); - GET_FLOAT_WORD(hy,y); - ix = hx&0x7fffffff; // |x| - iy = hy&0x7fffffff; // |y| + GLM_GET_FLOAT_WORD(hx,x); + GLM_GET_FLOAT_WORD(hy,y); + ix = hx&0x7fffffff; // |x| + iy = hy&0x7fffffff; // |y| - if((ix>0x7f800000) || // x is nan - (iy>0x7f800000)) // y is nan - return x+y; - if(x==y) return y; // x=y, return y - if(ix==0) { // x == 0 - SET_FLOAT_WORD(x,(hy&0x80000000)|1);// return +-minsubnormal - t = x*x; - if(t==x) return t; else return x; // raise underflow flag - } - if(hx>=0) { // x > 0 - if(hx>hy) { // x > y, x -= ulp - hx -= 1; - } else { // x < y, x += ulp - hx += 1; - } - } else { // x < 0 - if(hy>=0||hx>hy){ // x < y, x -= ulp - hx -= 1; - } else { // x > y, x += ulp - hx += 1; - } - } - hy = hx&0x7f800000; - if(hy>=0x7f800000) return x+x; // overflow - if(hy<0x00800000) { // underflow - t = x*x; - if(t!=x) { // raise underflow flag - SET_FLOAT_WORD(y,hx); - return y; - } - } - SET_FLOAT_WORD(x,hx); - return x; -} -*/ -/* -double nextafter(double x, double y) -{ - volatile double t; - int32_t hx,hy,ix,iy; - u_int32_t lx,ly; + if((ix>0x7f800000) || // x is nan + (iy>0x7f800000)) // y is nan + return x+y; + if(x==y) return y; // x=y, return y + if(ix==0) { // x == 0 + GLM_SET_FLOAT_WORD(x,(hy&0x80000000)|1);// return +-minsubnormal + t = x*x; + if(t==x) return t; else return x; // raise underflow flag + } + if(hx>=0) { // x > 0 + if(hx>hy) { // x > y, x -= ulp + hx -= 1; + } else { // x < y, x += ulp + hx += 1; + } + } else { // x < 0 + if(hy>=0||hx>hy){ // x < y, x -= ulp + hx -= 1; + } else { // x > y, x += ulp + hx += 1; + } + } + hy = hx&0x7f800000; + if(hy>=0x7f800000) return x+x; // overflow + if(hy<0x00800000) { // underflow + t = x*x; + if(t!=x) { // raise underflow flag + GLM_SET_FLOAT_WORD(y,hx); + return y; + } + } + GLM_SET_FLOAT_WORD(x,hx); + return x; + } - EXTRACT_WORDS(hx,lx,x); - EXTRACT_WORDS(hy,ly,y); - ix = hx&0x7fffffff; // |x| - iy = hy&0x7fffffff; // |y| + GLM_FUNC_QUALIFIER double nextafter(double x, double y) + { + volatile double t; + glm::int32 hx, hy, ix, iy; + glm::uint32 lx, ly; - if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) || // x is nan - ((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) // y is nan - return x+y; - if(x==y) return y; // x=y, return y - if((ix|lx)==0) { // x == 0 - INSERT_WORDS(x,hy&0x80000000,1); // return +-minsubnormal - t = x*x; - if(t==x) return t; else return x; // raise underflow flag - } - if(hx>=0) { // x > 0 - if(hx>hy||((hx==hy)&&(lx>ly))) { // x > y, x -= ulp - if(lx==0) hx -= 1; - lx -= 1; - } else { // x < y, x += ulp - lx += 1; - if(lx==0) hx += 1; - } - } else { // x < 0 - if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){// x < y, x -= ulp - if(lx==0) hx -= 1; - lx -= 1; - } else { // x > y, x += ulp - lx += 1; - if(lx==0) hx += 1; - } - } - hy = hx&0x7ff00000; - if(hy>=0x7ff00000) return x+x; // overflow - if(hy<0x00100000) { // underflow - t = x*x; - if(t!=x) { // raise underflow flag - INSERT_WORDS(y,hx,lx); - return y; - } - } - INSERT_WORDS(x,hx,lx); - return x; -} -*/ + GLM_EXTRACT_WORDS(hx, lx, x); + GLM_EXTRACT_WORDS(hy, ly, y); + ix = hx & 0x7fffffff; // |x| + iy = hy & 0x7fffffff; // |y| + + if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) || // x is nan + ((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) // y is nan + return x+y; + if(x==y) return y; // x=y, return y + if((ix|lx)==0) { // x == 0 + GLM_INSERT_WORDS(x, hy & 0x80000000, 1); // return +-minsubnormal + t = x*x; + if(t==x) return t; else return x; // raise underflow flag + } + if(hx>=0) { // x > 0 + if(hx>hy||((hx==hy)&&(lx>ly))) { // x > y, x -= ulp + if(lx==0) hx -= 1; + lx -= 1; + } else { // x < y, x += ulp + lx += 1; + if(lx==0) hx += 1; + } + } else { // x < 0 + if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){// x < y, x -= ulp + if(lx==0) hx -= 1; + lx -= 1; + } else { // x > y, x += ulp + lx += 1; + if(lx==0) hx += 1; + } + } + hy = hx&0x7ff00000; + if(hy>=0x7ff00000) return x+x; // overflow + if(hy<0x00100000) { // underflow + t = x*x; + if(t!=x) { // raise underflow flag + GLM_INSERT_WORDS(y,hx,lx); + return y; + } + } + GLM_INSERT_WORDS(x,hx,lx); + return x; + } +}//namespace detail +}//namespace glm #if(GLM_COMPILER & GLM_COMPILER_VC) # if(GLM_MODEL == GLM_MODEL_32) -# define GLM_NEXT_AFTER_FLT(x, toward) (float)_nextafter(x, float(toward)) +# define GLM_NEXT_AFTER_FLT(x, toward) glm::detail::nextafter((x), (toward)) # else -# define GLM_NEXT_AFTER_FLT(x, toward) _nextafterf(x, toward) +# define GLM_NEXT_AFTER_FLT(x, toward) _nextafterf((x), (toward)) # endif -# define GLM_NEXT_AFTER_DBL(x, toward) _nextafter(x, toward) +# define GLM_NEXT_AFTER_DBL(x, toward) _nextafter((x), (toward)) #else -# define GLM_NEXT_AFTER_FLT(x, toward) nextafterf(x, toward) -# define GLM_NEXT_AFTER_DBL(x, toward) nextafter(x, toward) +# define GLM_NEXT_AFTER_FLT(x, toward) nextafterf((x), (toward)) +# define GLM_NEXT_AFTER_DBL(x, toward) nextafter((x), (toward)) #endif namespace glm{