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Diffstat (limited to 'silx/resources/opencl/doubleword.cl')
-rw-r--r-- | silx/resources/opencl/doubleword.cl | 115 |
1 files changed, 0 insertions, 115 deletions
diff --git a/silx/resources/opencl/doubleword.cl b/silx/resources/opencl/doubleword.cl deleted file mode 100644 index a0ebfda..0000000 --- a/silx/resources/opencl/doubleword.cl +++ /dev/null @@ -1,115 +0,0 @@ -/* - * OpenCL library for double word floating point calculation using compensated arithmetics - * - * The theoritical basis can be found in Valentina Popescu's PhD thesis: - * Towards fast and certified multi-precision libraries - * Reference LYSEN036 - * http://www.theses.fr/2017LYSEN036 - * All page number and equation number are refering to this document. - * - * The precision of the calculation (bounds) is provided in ULP (smallest possible mantissa) - * and come from the table 2.2 (page 68 of the thesis). - * The number of equivalent FLOP is taken from the table 2.3 (page 69 the thesis). - * Note that FLOP are not all equal: a division is much more expensive than an addition. - */ - -//This library can be expanded to double-double by redefining fp, fp2 and one to double, double2 and 1.0. -#ifdef DOUBLEDOUBLE -#define fp double -#define fp2 double2 -#define one 1.0 -#else -#define fp float -#define fp2 float2 -#define one 1.0f -#endif - -/* Nota: i386 computer use x87 registers which are larger than the 32bits precision - * which can invalidate the error compensation mechanism. - * - * We use the trick to declare some variable "volatile" to enforce the actual - * precision reduction of those variables. -*/ - -#ifndef X87_VOLATILE -# define X87_VOLATILE -#endif - -//Algorithm 1, p23, theorem 1.1.12. Requires e_x > e_y, valid if |x| > |y| -inline fp2 fast_fp_plus_fp(fp x, fp y){ - X87_VOLATILE fp s = x + y; - X87_VOLATILE fp z = s - x; - fp e = y - z; - return (fp2)(s, e); -} - -//Algorithm 2, p24, same as fast_fp_plus_fp without the condition on e_x and e_y -inline fp2 fp_plus_fp(fp x, fp y){ - X87_VOLATILE fp s = x + y; - X87_VOLATILE fp xp = s - y; - X87_VOLATILE fp yp = s - xp; - X87_VOLATILE fp dx = x - xp; - X87_VOLATILE fp dy = y - yp; - return (fp2)(s, dx+dy); -} - -//Algorithm 3, p24: multiplication with a FMA -inline fp2 fp_times_fp(fp x, fp y){ - fp p = x * y; - fp e = fma(x, y, -p); - return (fp2)(p, e); -} - -//Algorithm 7, p38: Addition of a FP to a DW. 10flop bounds:2u²+5u³ -inline fp2 dw_plus_fp(fp2 x, fp y){ - fp2 s = fp_plus_fp(x.s0, y); - X87_VOLATILE fp v = x.s1 + s.s1; - return fast_fp_plus_fp(s.s0, v); -} - -//Algorithm 9, p40: addition of two DW: 20flop bounds:3u²+13u³ -inline fp2 dw_plus_dw(fp2 x, fp2 y){ - fp2 s = fp_plus_fp(x.s0, y.s0); - fp2 t = fp_plus_fp(x.s1, y.s1); - fp2 v = fast_fp_plus_fp(s.s0, s.s1 + t.s0); - return fast_fp_plus_fp(v.s0, t.s1 + v.s1); -} - -//Algorithm 12, p49: Multiplication FP*DW: 6flops bounds:2u² -inline fp2 dw_times_fp(fp2 x, fp y){ - fp2 c = fp_times_fp(x.s0, y); - return fast_fp_plus_fp(c.s0, fma(x.s1, y, c.s1)); -} - -//Algorithm 14, p52: Multiplication DW*DW, 8 flops bounds:6u² -inline fp2 dw_times_dw(fp2 x, fp2 y){ - fp2 c = fp_times_fp(x.s0, y.s0); - X87_VOLATILE fp l = fma(x.s1, y.s0, x.s0 * y.s1); - return fast_fp_plus_fp(c.s0, c.s1 + l); -} - -//Algorithm 17, p55: Division DW / FP, 10flops bounds: 3.5u² -inline fp2 dw_div_fp(fp2 x, fp y){ - X87_VOLATILE fp th = x.s0 / y; - fp2 pi = fp_times_fp(th, y); - fp2 d = x - pi; - X87_VOLATILE fp delta = d.s0 + d.s1; - X87_VOLATILE fp tl = delta/y; - return fast_fp_plus_fp(th, tl); -} - -//Derived from algorithm 20, p64: Inversion 1/ DW, 22 flops -inline fp2 inv_dw(fp2 y){ - X87_VOLATILE fp th = one/y.s0; - X87_VOLATILE fp rh = fma(-y.s0, th, one); - X87_VOLATILE fp rl = -y.s1 * th; - fp2 e = fast_fp_plus_fp(rh, rl); - fp2 delta = dw_times_fp(e, th); - return dw_plus_fp(delta, th); -} - -//Algorithm 20, p64: Division DW / DW, 30 flops: bounds:9.8u² -inline fp2 dw_div_dw(fp2 x, fp2 y){ - return dw_times_dw(x, inv_dw(y)); -} - |