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2008-11-26 Ken Werner <ken.werner@de.ibm.com>

* libm/machine/spu/headers/acosd2.h: Rebase against current simdmath.
        * libm/machine/spu/headers/asind2.h: Likewise.
        * libm/machine/spu/headers/asinhf4.h: Likewise.
        * libm/machine/spu/headers/divd2.h: Likewise.
        * libm/machine/spu/headers/erf_utils.h: Likewise.
        * libm/machine/spu/headers/erfcd2.h: Likewise.
        * libm/machine/spu/headers/erfcf4.h: Likewise.
        * libm/machine/spu/headers/erfd2.h: Likewise.
        * libm/machine/spu/headers/recipd2.h: Likewise.
This commit is contained in:
Jeff Johnston 2008-11-26 19:59:25 +00:00
parent 15c509b515
commit 14535fc538
10 changed files with 644 additions and 352 deletions

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@ -1,3 +1,15 @@
2008-11-26 Ken Werner <ken.werner@de.ibm.com>
* libm/machine/spu/headers/acosd2.h: Rebase against current simdmath.
* libm/machine/spu/headers/asind2.h: Likewise.
* libm/machine/spu/headers/asinhf4.h: Likewise.
* libm/machine/spu/headers/divd2.h: Likewise.
* libm/machine/spu/headers/erf_utils.h: Likewise.
* libm/machine/spu/headers/erfcd2.h: Likewise.
* libm/machine/spu/headers/erfcf4.h: Likewise.
* libm/machine/spu/headers/erfd2.h: Likewise.
* libm/machine/spu/headers/recipd2.h: Likewise.
2008-11-25 Corinna Vinschen <corinna@vinschen.de> 2008-11-25 Corinna Vinschen <corinna@vinschen.de>
* libc/stdio/gets.c (_gets_r): Lock stdin here and call * libc/stdio/gets.c (_gets_r): Lock stdin here and call

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@ -40,9 +40,8 @@
#ifndef _ACOSD2_H_ #ifndef _ACOSD2_H_
#define _ACOSD2_H_ 1 #define _ACOSD2_H_ 1
#include <spu_intrinsics.h>
#include "simdmath.h" #include "simdmath.h"
#include <spu_intrinsics.h>
#include "sqrtd2.h" #include "sqrtd2.h"
#include "divd2.h" #include "divd2.h"

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@ -41,9 +41,8 @@
#ifndef _ASIND2_H_ #ifndef _ASIND2_H_
#define _ASIND2_H_ 1 #define _ASIND2_H_ 1
#include <spu_intrinsics.h>
#include "simdmath.h" #include "simdmath.h"
#include <spu_intrinsics.h>
#include "sqrtd2.h" #include "sqrtd2.h"
#include "divd2.h" #include "divd2.h"

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@ -96,8 +96,8 @@
#define ASINH_MAC25 6.4472103118896484375000000000000000000000000000000000000000000000000000E-3 #define ASINH_MAC25 6.4472103118896484375000000000000000000000000000000000000000000000000000E-3
#define ASINH_MAC27 -5.7400376708419234664351851851851851851851851851851851851851851851851852E-3 #define ASINH_MAC27 -5.7400376708419234664351851851851851851851851851851851851851851851851852E-3
#define ASINH_MAC29 5.1533096823199041958512931034482758620689655172413793103448275862068966E-3 #define ASINH_MAC29 5.1533096823199041958512931034482758620689655172413793103448275862068966E-3
#if 0
#define ASINH_MAC31 -4.6601434869150961599042338709677419354838709677419354838709677419354839E-3 #define ASINH_MAC31 -4.6601434869150961599042338709677419354838709677419354838709677419354839E-3
#if 0
#define ASINH_MAC33 4.2409070936793630773370916193181818181818181818181818181818181818181818E-3 #define ASINH_MAC33 4.2409070936793630773370916193181818181818181818181818181818181818181818E-3
#define ASINH_MAC35 -3.8809645588376692363194056919642857142857142857142857142857142857142857E-3 #define ASINH_MAC35 -3.8809645588376692363194056919642857142857142857142857142857142857142857E-3
#define ASINH_MAC37 3.5692053938259345454138678473395270270270270270270270270270270270270270E-3 #define ASINH_MAC37 3.5692053938259345454138678473395270270270270270270270270270270270270270E-3
@ -107,34 +107,43 @@
#endif #endif
static __inline vector float _asinhf4(vector float x) static __inline vector float _asinhf4(vector float x)
{ {
vec_float4 sign_mask = spu_splats(-0.0f); vec_float4 sign_mask = spu_splats(-0.0f);
vec_float4 onef = spu_splats(1.0f); vec_float4 onef = spu_splats(1.0f);
vec_float4 result, fresult, mresult;; vec_uint4 oneu = spu_splats(1u);
vec_uint4 twou = spu_splats(2u);
vec_uint4 threeu = spu_splats(3u);
vec_float4 ln2 = spu_splats(6.931471805599453094172321E-1f);
vec_float4 largef = spu_splats(9.21e18f);
vec_float4 result, fresult, mresult;
vec_float4 xabs, xsqu; vec_float4 xabs, xsqu;
/* Where we switch from maclaurin to formula */ /* Where we switch from maclaurin to formula */
vec_float4 switch_approx = spu_splats(0.685f); vec_float4 switch_approx = spu_splats(0.74f);
vec_float4 trunc_part2 = spu_splats(20.0f);
vec_uint4 truncadd;
vec_uint4 islarge;
vec_uint4 use_form; vec_uint4 use_form;
xabs = spu_andc(x, sign_mask); xabs = spu_andc(x, sign_mask);
xsqu = spu_mul(x, x); xsqu = spu_mul(x, x);
islarge = spu_cmpgt(xabs, largef);
/* /*
* Formula: * Formula:
* asinh = ln(|x| + sqrt(x^2 + 1)) * asinh = ln(|x| + sqrt(x^2 + 1))
*/ */
fresult = _sqrtf4(spu_madd(x, x, onef));
fresult = spu_add(xabs, fresult);
fresult = _logf4(fresult);
vec_float4 logarg = spu_add(xabs, _sqrtf4(spu_madd(xabs, xabs, onef)));
logarg = spu_sel(logarg, xabs, islarge);
fresult = _logf4(logarg);
fresult = spu_sel(fresult, spu_add(fresult, ln2), islarge);
/* /*
* Maclaurin Series * Maclaurin Series
*/ */
mresult = spu_madd(xsqu, spu_splats((float)ASINH_MAC29), spu_splats((float)ASINH_MAC27)); mresult = spu_madd(xsqu, spu_splats((float)ASINH_MAC31), spu_splats((float)ASINH_MAC29));
mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC27));
mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC25)); mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC25));
mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC23)); mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC23));
mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC21)); mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC21));
@ -150,13 +159,18 @@ static __inline vector float _asinhf4(vector float x)
mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC01)); mresult = spu_madd(xsqu, mresult, spu_splats((float)ASINH_MAC01));
mresult = spu_mul(xabs, mresult); mresult = spu_mul(xabs, mresult);
/* /*
* Choose between series and formula * Choose between series and formula
*/ */
use_form = spu_cmpgt(xabs, switch_approx); use_form = spu_cmpgt(xabs, switch_approx);
result = spu_sel(mresult, fresult, use_form); result = spu_sel(mresult, fresult, use_form);
/*
* Truncation correction on spu
*/
truncadd = spu_sel(oneu, threeu, use_form);
truncadd = spu_sel(truncadd, twou, spu_cmpgt(xabs, trunc_part2));
result = (vec_float4)spu_add((vec_uint4)result, truncadd);
/* Preserve sign - asinh is anti-symmetric */ /* Preserve sign - asinh is anti-symmetric */
result = spu_sel(result, x, (vec_uint4)sign_mask); result = spu_sel(result, x, (vec_uint4)sign_mask);

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@ -51,65 +51,115 @@
* *
* DESCRIPTION * DESCRIPTION
* _divd2 divides the vector dividend a by the vector divisor b and * _divd2 divides the vector dividend a by the vector divisor b and
* returns the resulting vector quotient. Maximum error 0.5 ULPS for * returns the resulting vector quotient. Maximum error about 0.5 ulp
* normalized results, 1ulp for denorm results, over entire double * over entire double range including denorms, compared to true result
* range including denorms, compared to true result in round-to-nearest * in round-to-nearest rounding mode. Handles Inf or NaN operands and
* rounding mode. Handles Inf or NaN operands and results correctly. * results correctly.
*/ */
static __inline vector double _divd2(vector double a, vector double b) static __inline vector double _divd2(vector double a_in, vector double b_in)
{ {
/* Variables */
vec_int4 exp, exp_bias;
/* Variables vec_uint4 no_underflow, overflow;
*/ vec_float4 mant_bf, inv_bf;
vec_float4 inv_bf, mant_bf; vec_ullong2 exp_a, exp_b;
vec_ullong2 a_nan, a_zero, a_inf, a_denorm;
vec_ullong2 b_nan, b_zero, b_inf, b_denorm;
vec_ullong2 nan;
vec_double2 a, b;
vec_double2 mant_a, mant_b, inv_b, q0, q1, q2, mult; vec_double2 mant_a, mant_b, inv_b, q0, q1, q2, mult;
vec_int4 exp, tmp;
vec_uint4 exp_a, exp_b, exp_q1, overflow, nounderflow, normal, utmp,
sign_a, sign_b, a_frac, b_frac, a_frac_0, b_frac_0, a_exp_0, b_exp_0,
a_exp_ones, b_exp_ones, a_nan, b_nan, a_inf, b_inf, a_zero, b_zero,
res_nan, sign_res;
/* Constants /* Constants */
*/ vec_float4 onef = spu_splats(1.0f);
vec_float4 onef = spu_splats(1.0f); vec_ullong2 exp_mask = spu_splats(0x7FF0000000000000ULL);
vec_double2 one = spu_splats(1.0); vec_double2 one = spu_splats(1.0);
vec_uint4 exp_mask = (vec_uint4) { 0x7FF00000, 0, 0x7FF00000, 0 };
vec_uint4 sign_mask = (vec_uint4) { 0x80000000, 0, 0x80000000, 0};
vec_uint4 sign_exp_mask = (vec_uint4) { 0xFFF00000, 0, 0xFFF00000,0};
vec_uint4 frac_mask =(vec_uint4) { 0x000FFFFF, 0xFFFFFFFF, 0x000FFFFF, 0xFFFFFFFF };
vec_uchar16 swap32 = (vec_uchar16) ((vec_uint4) { 0x04050607, 0x00010203, 0x0C0D0E0F, 0x08090A0B} );
vec_uint4 zero = (vec_uint4) { 0, 0, 0, 0 };
vec_int4 e1022 = (vec_int4) { 0x000003FE, 0, 0x000003FE, 0 };
vec_int4 emax = (vec_int4) { 0x000007FE, 0, 0x000007FE, 0 };
vec_int4 e1 = (vec_int4) { 0x00000001, 0, 0x00000001, 0 };
vec_uint4 nan = (vec_uint4) { 0x7FF80000, 0, 0x7FF80000, 0}; #ifdef __SPU_EDP__
vec_double2 denorm_scale = (vec_double2)spu_splats(0x4330000000000000ULL);
/* Extract exponents and underflow denorm arguments to signed zero. /* Identify all possible special values that must be accomodated including:
* +-0, +-infinity, +-denorm, and NaNs.
*/ */
exp_a = spu_and((vec_uint4)a, exp_mask); a_nan = spu_testsv(a_in, (SPU_SV_NAN));
exp_b = spu_and((vec_uint4)b, exp_mask); a_zero = spu_testsv(a_in, (SPU_SV_NEG_ZERO | SPU_SV_POS_ZERO));
a_inf = spu_testsv(a_in, (SPU_SV_NEG_INFINITY | SPU_SV_POS_INFINITY));
a_denorm = spu_testsv(a_in, (SPU_SV_NEG_DENORM | SPU_SV_POS_DENORM));
sign_a = spu_and((vec_uint4)a, sign_mask); b_nan = spu_testsv(b_in, (SPU_SV_NAN));
sign_b = spu_and((vec_uint4)b, sign_mask); b_zero = spu_testsv(b_in, (SPU_SV_NEG_ZERO | SPU_SV_POS_ZERO));
b_inf = spu_testsv(b_in, (SPU_SV_NEG_INFINITY | SPU_SV_POS_INFINITY));
b_denorm = spu_testsv(b_in, (SPU_SV_NEG_DENORM | SPU_SV_POS_DENORM));
a_exp_0 = spu_cmpeq (exp_a, 0); /* Scale denorm inputs to into normalized numbers by conditionally scaling the
utmp = spu_shuffle (a_exp_0, a_exp_0, swap32); * input parameters.
a_exp_0 = spu_and (a_exp_0, utmp); */
b_exp_0 = spu_cmpeq (exp_b, 0); a = spu_sel(a_in, spu_mul(a_in, denorm_scale), a_denorm);
utmp = spu_shuffle (b_exp_0, b_exp_0, swap32); b = spu_sel(b_in, spu_mul(b_in, denorm_scale), b_denorm);
b_exp_0 = spu_and (b_exp_0, utmp);
a = spu_sel(a, (vec_double2)sign_a, (vec_ullong2)a_exp_0); #else /* !__SPU_EDP__ */
b = spu_sel(b, (vec_double2)sign_b, (vec_ullong2)b_exp_0); vec_uint4 a_exp, b_exp;
vec_ullong2 a_mant_0, b_mant_0;
vec_ullong2 a_exp_1s, b_exp_1s;
vec_ullong2 sign_exp_mask;
/* Force the divisor and dividend into the range [1.0,2.0). vec_uint4 exp_mask_u32 = spu_splats((unsigned int)0x7FF00000);
(Unless they're zero.) vec_uchar16 splat_hi = (vec_uchar16){0,1,2,3, 0,1,2,3, 8, 9,10,11, 8,9,10,11};
*/ vec_uchar16 swap_32 = (vec_uchar16){4,5,6,7, 0,1,2,3, 12,13,14,15, 8,9,10,11};
mant_a = spu_sel(a, one, (vec_ullong2)sign_exp_mask); vec_ullong2 sign_mask = spu_splats(0x8000000000000000ULL);
mant_b = spu_sel(b, one, (vec_ullong2)sign_exp_mask); vec_double2 exp_53 = (vec_double2)spu_splats(0x0350000000000000ULL);
sign_exp_mask = spu_or(sign_mask, exp_mask);
/* Extract the floating point components from each of the operands including
* exponent and mantissa.
*/
a_exp = (vec_uint4)spu_and((vec_uint4)a_in, exp_mask_u32);
a_exp = spu_shuffle(a_exp, a_exp, splat_hi);
b_exp = (vec_uint4)spu_and((vec_uint4)b_in, exp_mask_u32);
b_exp = spu_shuffle(b_exp, b_exp, splat_hi);
a_mant_0 = (vec_ullong2)spu_cmpeq((vec_uint4)spu_andc((vec_ullong2)a_in, sign_exp_mask), 0);
a_mant_0 = spu_and(a_mant_0, spu_shuffle(a_mant_0, a_mant_0, swap_32));
b_mant_0 = (vec_ullong2)spu_cmpeq((vec_uint4)spu_andc((vec_ullong2)b_in, sign_exp_mask), 0);
b_mant_0 = spu_and(b_mant_0, spu_shuffle(b_mant_0, b_mant_0, swap_32));
a_exp_1s = (vec_ullong2)spu_cmpeq(a_exp, exp_mask_u32);
b_exp_1s = (vec_ullong2)spu_cmpeq(b_exp, exp_mask_u32);
/* Identify all possible special values that must be accomodated including:
* +-denorm, +-0, +-infinity, and NaNs.
*/
a_denorm = (vec_ullong2)spu_cmpeq(a_exp, 0); /* really is a_exp_0 */
a_nan = spu_andc(a_exp_1s, a_mant_0);
a_zero = spu_and (a_denorm, a_mant_0);
a_inf = spu_and (a_exp_1s, a_mant_0);
b_denorm = (vec_ullong2)spu_cmpeq(b_exp, 0); /* really is b_exp_0 */
b_nan = spu_andc(b_exp_1s, b_mant_0);
b_zero = spu_and (b_denorm, b_mant_0);
b_inf = spu_and (b_exp_1s, b_mant_0);
/* Scale denorm inputs to into normalized numbers by conditionally scaling the
* input parameters.
*/
a = spu_sub(spu_or(a_in, exp_53), spu_sel(exp_53, a_in, sign_mask));
a = spu_sel(a_in, a, a_denorm);
b = spu_sub(spu_or(b_in, exp_53), spu_sel(exp_53, b_in, sign_mask));
b = spu_sel(b_in, b, b_denorm);
#endif /* __SPU_EDP__ */
/* Extract the divisor and dividend exponent and force parameters into the signed
* range [1.0,2.0) or [-1.0,2.0).
*/
exp_a = spu_and((vec_ullong2)a, exp_mask);
exp_b = spu_and((vec_ullong2)b, exp_mask);
mant_a = spu_sel(a, one, (vec_ullong2)exp_mask);
mant_b = spu_sel(b, one, (vec_ullong2)exp_mask);
/* Approximate the single reciprocal of b by using /* Approximate the single reciprocal of b by using
* the single precision reciprocal estimate followed by one * the single precision reciprocal estimate followed by one
* single precision iteration of Newton-Raphson. * single precision iteration of Newton-Raphson.
@ -118,112 +168,67 @@ static __inline vector double _divd2(vector double a, vector double b)
inv_bf = spu_re(mant_bf); inv_bf = spu_re(mant_bf);
inv_bf = spu_madd(spu_nmsub(mant_bf, inv_bf, onef), inv_bf, inv_bf); inv_bf = spu_madd(spu_nmsub(mant_bf, inv_bf, onef), inv_bf, inv_bf);
/* Perform 2 more Newton-Raphson iterations in double precision. /* Perform 2 more Newton-Raphson iterations in double precision. The
* result (q1) is in the range (0.5, 2.0).
*/ */
inv_b = spu_extend(inv_bf); inv_b = spu_extend(inv_bf);
inv_b = spu_madd(spu_nmsub(mant_b, inv_b, one), inv_b, inv_b); inv_b = spu_madd(spu_nmsub(mant_b, inv_b, one), inv_b, inv_b);
q0 = spu_mul(mant_a, inv_b); q0 = spu_mul(mant_a, inv_b);
q1 = spu_madd(spu_nmsub(mant_b, q0, mant_a), inv_b, q0); q1 = spu_madd(spu_nmsub(mant_b, q0, mant_a), inv_b, q0);
/* Compute the quotient's expected exponent. If the exponent
* is out of range, then force the resulting exponent to 0. /* Determine the exponent correction factor that must be applied
* (1023 with the bias). We correct for the out of range * to q1 by taking into account the exponent of the normalized inputs
* values by computing a multiplier (mult) that will force the * and the scale factors that were applied to normalize them.
* result to the correct out of range value and set the
* correct exception flag (UNF, OVF, or neither).
*/ */
exp_q1 = spu_and((vec_uint4)q1, exp_mask); exp = spu_rlmaska(spu_sub((vec_int4)exp_a, (vec_int4)exp_b), -20);
exp = spu_sub((vec_int4)exp_a, (vec_int4)exp_b); exp = spu_add(exp, (vec_int4)spu_add(spu_and((vec_int4)a_denorm, -0x34), spu_and((vec_int4)b_denorm, 0x34)));
exp = spu_rlmaska(exp, -20); // shift right to allow enough bits for working
tmp = spu_rlmaska((vec_int4)exp_q1, -20);
exp = spu_add(exp, tmp); // biased exponent of result (right justified)
/* The default multiplier is 1.0. If an underflow is detected (the computed
* exponent is less than or equal to a biased 0), force the multiplier to 0.0.
* If exp<=0 set mult = 2**(unbiased exp + 1022) and unbiased exp = -1022
* = biased 1, the smallest normalized exponent. If exp<-51 set
* mult = 2**(-1074) to ensure underflowing result. Otherwise mult=1.
*/
normal = spu_cmpgt(exp, 0);
nounderflow = spu_cmpgt(exp, -52);
tmp = spu_add(exp, e1022);
mult = (vec_double2)spu_sl(tmp, 20);
mult = spu_sel(mult, one, (vec_ullong2)normal);
mult = spu_sel((vec_double2)e1, mult, (vec_ullong2)nounderflow);
exp = spu_sel(e1, exp, normal); // unbiased -1022 is biased 1
/* Force the multiplier to positive infinity (exp_mask) and the biased
* exponent to 1022, if the computed biased exponent is > emax.
*/
overflow = spu_cmpgt(exp, (vec_int4)emax);
exp = spu_sel(exp, (vec_int4)e1022, overflow);
mult = spu_sel(mult, (vec_double2)exp_mask, (vec_ullong2)overflow);
/* Determine if a, b are Inf, NaN, or zero.
* Since these are rare, it would improve speed if these could be detected
* quickly and a branch used to avoid slowing down the main path. However
* most of the work seems to be in the detection.
*/
a_exp_ones = spu_cmpeq (exp_a, exp_mask);
utmp = spu_shuffle (a_exp_ones, a_exp_ones, swap32);
a_exp_ones = spu_and (a_exp_ones, utmp);
a_frac = spu_and ((vec_uint4)a, frac_mask);
a_frac_0 = spu_cmpeq (a_frac, 0);
utmp = spu_shuffle (a_frac_0, a_frac_0, swap32);
a_frac_0 = spu_and (a_frac_0, utmp);
a_zero = spu_and (a_exp_0, a_frac_0);
a_inf = spu_and (a_exp_ones, a_frac_0);
a_nan = spu_andc (a_exp_ones, a_frac_0);
b_exp_ones = spu_cmpeq (exp_b, exp_mask);
utmp = spu_shuffle (b_exp_ones, b_exp_ones, swap32);
b_exp_ones = spu_and (b_exp_ones, utmp);
b_frac = spu_and ((vec_uint4)b, frac_mask);
b_frac_0 = spu_cmpeq (b_frac, 0);
utmp = spu_shuffle (b_frac_0, b_frac_0, swap32);
b_frac_0 = spu_and (b_frac_0, utmp);
b_zero = spu_and (b_exp_0, b_frac_0);
b_inf = spu_and (b_exp_ones, b_frac_0);
b_nan = spu_andc (b_exp_ones, b_frac_0);
/* Handle exception cases */
/* Result is 0 for 0/x, x!=0, or x/Inf, x!=Inf.
* Set mult=0 for 0/0 or Inf/Inf now, since it will be replaced
* with NaN later.
*/
utmp = spu_or (a_zero, b_inf);
mult = spu_sel(mult, (vec_double2)zero, (vec_ullong2)utmp);
/* Result is Inf for x/0, x!=0. Set mult=Inf for 0/0 now, since it
* will be replaced with NaN later.
*/
mult = spu_sel(mult, (vec_double2)exp_mask, (vec_ullong2)b_zero);
/* Result is NaN if either operand is, or Inf/Inf, or 0/0.
*/
res_nan = spu_or (a_nan, b_nan);
utmp = spu_and (a_inf, b_inf);
res_nan = spu_or (res_nan, utmp);
utmp = spu_and (a_zero, b_zero);
res_nan = spu_or (res_nan, utmp);
mult = spu_sel(mult, (vec_double2)nan, (vec_ullong2)res_nan);
/* Insert sign of result into mult. /* Bias the quotient exponent depending on the sign of the exponent correction
* factor so that a single multiplier will ensure the entire double precision
* domain (including denorms) can be achieved.
*
* exp bias q1 adjust exp
* ===== ======== ==========
* positive 2^+65 -65
* negative 2^-64 +64
*/ */
sign_res = spu_xor (sign_a, sign_b); exp_bias = spu_xor(spu_rlmaska(exp, -31), 64);
mult = spu_or (mult, (vec_double2)sign_res);
/* Insert the sign and exponent into the result and perform the
* final multiplication. exp = spu_sub(exp, exp_bias);
q1 = spu_sel(q1, (vec_double2)spu_add((vec_int4)q1, spu_sl(exp_bias, 20)), exp_mask);
/* Compute a multiplier (mult) to applied to the quotient (q1) to produce the
* expected result.
*/ */
exp = spu_sl(exp, 20); exp = spu_add(exp, 0x3FF);
q2 = spu_sel(q1, (vec_double2)exp, (vec_ullong2)exp_mask); no_underflow = spu_cmpgt(exp, 0);
q2 = spu_mul(q2, mult); overflow = spu_cmpgt(exp, 0x7FF);
exp = spu_and(spu_sl(exp, 20), (vec_int4)no_underflow);
exp = spu_and(exp, (vec_int4)exp_mask);
mult = spu_sel((vec_double2)exp, (vec_double2)exp_mask, (vec_ullong2)overflow);
/* Handle special value conditions. These include:
*
* 1) IF either operand is a NaN OR both operands are 0 or INFINITY THEN a NaN
* results.
* 2) ELSE IF the dividend is an INFINITY OR the divisor is 0 THEN a INFINITY results.
* 3) ELSE IF the dividend is 0 OR the divisor is INFINITY THEN a 0 results.
*/
mult = spu_andc(mult, (vec_double2)spu_or(a_zero, b_inf));
mult = spu_sel(mult, (vec_double2)exp_mask, spu_or(a_inf, b_zero));
nan = spu_or(a_nan, b_nan);
nan = spu_or(nan, spu_and(a_zero, b_zero));
nan = spu_or(nan, spu_and(a_inf, b_inf));
mult = spu_or(mult, (vec_double2)nan);
/* Scale the final quotient */
q2 = spu_mul(q1, mult);
return (q2); return (q2);
} }

View File

@ -166,57 +166,6 @@
_tresult = spu_mul(_tresult, spu_splats(TWO_OVER_SQRT_PI)); \ _tresult = spu_mul(_tresult, spu_splats(TWO_OVER_SQRT_PI)); \
} }
#define TAYLOR_ERFF4(_xabs, _xsqu, _tresult) { \
_tresult = spu_madd(_xsqu, spu_splats((float)TAYLOR_ERF_45), spu_splats((float)TAYLOR_ERF_44)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_43)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_42)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_41)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_40)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_39)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_38)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_37)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_36)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_35)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_34)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_33)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_32)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_31)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_30)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_29)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_28)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_27)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_26)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_25)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_24)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_23)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_22)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_21)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_20)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_19)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_18)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_17)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_16)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_15)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_14)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_13)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_12)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_11)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_10)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_09)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_08)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_07)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_06)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_05)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_04)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_03)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_02)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_01)); \
_tresult = spu_madd(_tresult, _xsqu, spu_splats((float)TAYLOR_ERF_00)); \
_tresult = spu_mul(_tresult, _xabs); \
_tresult = spu_mul(_tresult, spu_splats((float)TWO_OVER_SQRT_PI)); \
}
/* /*
* Continued Fractions Approximation of Erfc() * Continued Fractions Approximation of Erfc()
@ -266,43 +215,7 @@
vec_float4 inv_xsqu; \ vec_float4 inv_xsqu; \
inv_xsqu = _recipf4(_xsqu); \ inv_xsqu = _recipf4(_xsqu); \
v = spu_mul(inv_xsqu, onehalff); \ v = spu_mul(inv_xsqu, onehalff); \
p = spu_splats(3.025f); q = onef; plast = p; qlast = q; \ p = spu_splats(1.945f); q = onef; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(40.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(39.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(38.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(37.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(36.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(35.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(34.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(33.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(32.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(31.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(30.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(29.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(28.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(27.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(26.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(25.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(24.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(23.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(22.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(21.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(20.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(19.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(18.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(17.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(16.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(15.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(14.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(13.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(12.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(11.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats(10.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 9.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 8.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 7.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 6.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 5.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 4.0f)), plast); q = plast; plast = p; qlast = q; \ p = spu_madd(qlast, spu_mul(v, spu_splats( 4.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 3.0f)), plast); q = plast; plast = p; qlast = q; \ p = spu_madd(qlast, spu_mul(v, spu_splats( 3.0f)), plast); q = plast; plast = p; qlast = q; \
p = spu_madd(qlast, spu_mul(v, spu_splats( 2.0f)), plast); q = plast; plast = p; qlast = q; \ p = spu_madd(qlast, spu_mul(v, spu_splats( 2.0f)), plast); q = plast; plast = p; qlast = q; \

View File

@ -80,15 +80,10 @@ static __inline vector double _erfcd2(vector double x)
vec_float4 approx_point = spu_splats(1.71f); vec_float4 approx_point = spu_splats(1.71f);
vec_double2 xabs, xsqu, xsign; vec_double2 xabs, xsqu, xsign;
vec_uint4 xhigh, xabshigh; vec_uint4 isneg;
vec_uint4 isnan, isneg;
vec_double2 tresult, presult, result; vec_double2 tresult, presult, result;
xsign = spu_and(x, sign_mask); xsign = spu_and(x, sign_mask);
/* Force Denorms to 0 */
x = spu_add(x, zerod);
xabs = spu_andc(x, sign_mask); xabs = spu_andc(x, sign_mask);
xsqu = spu_mul(x, x); xsqu = spu_mul(x, x);
@ -118,18 +113,11 @@ static __inline vector double _erfcd2(vector double x)
result = spu_sel(tresult, presult, (vec_ullong2)spu_cmpgt(xf, approx_point)); result = spu_sel(tresult, presult, (vec_ullong2)spu_cmpgt(xf, approx_point));
/* /*
* Special cases/errors. * Special cases
*/ */
xhigh = (vec_uint4)spu_shuffle(x, x, dup_even); result = spu_sel(result, twod, spu_testsv(x, SPU_SV_NEG_INFINITY));
xabshigh = (vec_uint4)spu_shuffle(xabs, xabs, dup_even); result = spu_sel(result, zerod, spu_testsv(x, SPU_SV_POS_INFINITY));
result = spu_sel(result, x, spu_testsv(x, SPU_SV_NEG_DENORM | SPU_SV_POS_DENORM));
/* x = +/- infinite */
result = spu_sel(result, zerod, (vec_ullong2)spu_cmpeq(xhigh, 0x7FF00000));
result = spu_sel(result, twod, (vec_ullong2)spu_cmpeq(xhigh, 0xFFF00000));
/* x = nan, return x */
isnan = spu_cmpgt(xabshigh, 0x7FF00000);
result = spu_sel(result, x, (vec_ullong2)isnan);
return result; return result;
} }

View File

@ -40,11 +40,11 @@
#define _ERFCF4_H_ 1 #define _ERFCF4_H_ 1
#include <spu_intrinsics.h> #include <spu_intrinsics.h>
#include "erff4.h"
#include "expf4.h"
#include "recipf4.h"
#include "divf4.h"
#include "erf_utils.h" #include "erf_utils.h"
#include "recipf4.h"
#include "expf4.h"
#include "divf4.h"
/* /*
* FUNCTION * FUNCTION
@ -63,56 +63,374 @@
static __inline vector float _erfcf4(vector float x) static __inline vector float _erfcf4(vector float x)
{ {
vec_float4 onehalff = spu_splats(0.5f); vec_float4 sign_maskf = spu_splats(-0.0f);
vec_float4 zerof = spu_splats(0.0f); vec_float4 zerof = spu_splats(0.0f);
vec_float4 onef = spu_splats(1.0f); vec_float4 onehalff = spu_splats(0.5f);
vec_float4 twof = spu_splats(2.0f); vec_float4 onef = spu_splats(1.0f);
vec_float4 sign_mask = spu_splats(-0.0f); vec_float4 twof = spu_splats(2.0f);
vec_float4 clamp = spu_splats(10.0542f); // Erfc = 0 above this (in single precision)
vec_float4 xabs = spu_andc(x, sign_maskf);
vec_float4 result;
/* This is where we switch from near zero approx. */ /*
vec_float4 approx_point = spu_splats(0.89f); * First thing we do is setup the description of each partition.
* This consists of:
* - Start x of partition
* - Offset (used for evaluating power series expanded around a point)
* - Truncation adjustment.
*/
vec_float4 xabs, xsqu, xsign;
vec_uint4 isneg;
vec_float4 tresult, presult, result;
xsign = spu_and(x, sign_mask); /***************************************************************
* REGION 0: Approximation Near 0 from Above
*
*/
#define SDM_ERFCF4_0_START 0.0f
#define SDM_ERFCF4_0_OFF 0.0f
#define SDM_ERFCF4_0_TRUNC 1u
/* Force Denorms to 0 */ #define SDM_ERFCF4_0_00 0.9999999999999949135f
x = spu_add(x, zerof); #define SDM_ERFCF4_0_01 -1.1283791670931702608f
#define SDM_ERFCF4_0_02 -1.8051894620430502228e-10f
#define SDM_ERFCF4_0_03 0.37612639455729408814f
#define SDM_ERFCF4_0_04 -8.8929793006257568262e-8f
#define SDM_ERFCF4_0_05 -0.11283705324835578294f
#define SDM_ERFCF4_0_06 -5.4670494993502827210e-6f
#define SDM_ERFCF4_0_07 0.026889802515535093351f
#define SDM_ERFCF4_0_08 -0.000071498114084857387620f
#define SDM_ERFCF4_0_09 -0.0050714210985129775210f
#define SDM_ERFCF4_0_10 -0.00022683372291701701701f
#define SDM_ERFCF4_0_11 0.0010796064437231401311f
#define SDM_ERFCF4_0_12 -0.00012982218714593684809f
#define SDM_ERFCF4_0_13 -0.00010102962499433144847f
#define SDM_ERFCF4_0_14 0.000025784829228223517886f
xabs = spu_andc(x, sign_mask);
/***************************************************************
* REGION 1: Near 1
*/
#define SDM_ERFCF4_1_START 0.88f
#define SDM_ERFCF4_1_OFF 1.125f
#define SDM_ERFCF4_1_TRUNC 1u
#define SDM_ERFCF4_1_00 0.111611768298292224f
#define SDM_ERFCF4_1_01 -0.318273958500769283f
#define SDM_ERFCF4_1_02 0.358058203313365464f
#define SDM_ERFCF4_1_03 -0.162452332984767661f
#define SDM_ERFCF4_1_04 -0.0279732971338566734f
#define SDM_ERFCF4_1_05 0.0613236836056658061f
#define SDM_ERFCF4_1_06 -0.0155368354497628942f
#define SDM_ERFCF4_1_07 -0.00960689422582997228f
#define SDM_ERFCF4_1_08 0.00603126088310672760f
#define SDM_ERFCF4_1_09 0.000360191989801368303f
#define SDM_ERFCF4_1_10 -0.00115326735470205975f
#define SDM_ERFCF4_1_11 0.000176955087857924673f
#define SDM_ERFCF4_1_12 0.000141558399011799664f
#define SDM_ERFCF4_1_13 -0.0000494556968345700811f
#define SDM_ERFCF4_1_14 0.0f
/***************************************************************
* REGION 2:
*/
#define SDM_ERFCF4_2_START 1.50f
#define SDM_ERFCF4_2_OFF 1.75f
#define SDM_ERFCF4_2_TRUNC 0u
#define SDM_ERFCF4_2_00 0.0133283287808175777f
#define SDM_ERFCF4_2_01 -0.0527749959301503715f
#define SDM_ERFCF4_2_02 0.0923562428777631589f
#define SDM_ERFCF4_2_03 -0.0901572847140068856f
#define SDM_ERFCF4_2_04 0.0481022098321682995f
#define SDM_ERFCF4_2_05 -0.00662436146831574865f
#define SDM_ERFCF4_2_06 -0.00896304509872736070f
#define SDM_ERFCF4_2_07 0.00605875147039124009f
#define SDM_ERFCF4_2_08 -0.000730051247140304322f
#define SDM_ERFCF4_2_09 -0.000894181745354844871f
#define SDM_ERFCF4_2_10 0.000442750499254694174f
#define SDM_ERFCF4_2_11 5.44549038611738718e-6f
#define SDM_ERFCF4_2_12 -0.0000686716770072681921f
#define SDM_ERFCF4_2_13 0.0000177205746526325771f
#define SDM_ERFCF4_2_14 0.0f
/***************************************************************
* REGION 3:
*/
#define SDM_ERFCF4_3_START 2.0f
#define SDM_ERFCF4_3_OFF 2.25f
#define SDM_ERFCF4_3_TRUNC 1u
#define SDM_ERFCF4_3_00 0.00146271658668117865f
#define SDM_ERFCF4_3_01 -0.00714231902201798319f
#define SDM_ERFCF4_3_02 0.0160702177995404628f
#define SDM_ERFCF4_3_03 -0.0217245536919713662f
#define SDM_ERFCF4_3_04 0.0190833836369542972f
#define SDM_ERFCF4_3_05 -0.0106576791656674587f
#define SDM_ERFCF4_3_06 0.00290435707106278173f
#define SDM_ERFCF4_3_07 0.000670455969951892490f
#define SDM_ERFCF4_3_08 -0.000999493712611392590f
#define SDM_ERFCF4_3_09 0.000369380417703939461f
#define SDM_ERFCF4_3_10 0.0000114665831641414663f
#define SDM_ERFCF4_3_11 -0.0000651349432823388933f
#define SDM_ERFCF4_3_12 0.0000226882426454011034f
#define SDM_ERFCF4_3_13 1.33207467538330703e-6f
#define SDM_ERFCF4_3_14 0.0f
/***************************************************************
* REGION 4:
*/
#define SDM_ERFCF4_4_START 2.46f
#define SDM_ERFCF4_4_OFF 2.75f
#define SDM_ERFCF4_4_TRUNC 1u
#define SDM_ERFCF4_4_00 0.000100621922119681351f
#define SDM_ERFCF4_4_01 -0.000586277247093792324f
#define SDM_ERFCF4_4_02 0.00161226242950792873f
#define SDM_ERFCF4_4_03 -0.00276038870506660526f
#define SDM_ERFCF4_4_04 0.00325811365963060576f
#define SDM_ERFCF4_4_05 -0.00275580841407368484f
#define SDM_ERFCF4_4_06 0.00165732740366604948f
#define SDM_ERFCF4_4_07 -0.000646040956672447276f
#define SDM_ERFCF4_4_08 0.0000890115712124397128f
#define SDM_ERFCF4_4_09 0.0000712231147231515843f
#define SDM_ERFCF4_4_10 -0.0000549969924243893176f
#define SDM_ERFCF4_4_11 0.0000158438047120425837f
#define SDM_ERFCF4_4_12 1.07113381370613701e-6f
#define SDM_ERFCF4_4_13 0.0f
#define SDM_ERFCF4_4_14 0.0f
/***************************************************************
* REGION 5:
*/
#define SDM_ERFCF4_5_START 2.95f
#define SDM_ERFCF4_5_OFF 3.25f
#define SDM_ERFCF4_5_TRUNC 1u
#define SDM_ERFCF4_5_00 4.30277946372736864e-6f
#define SDM_ERFCF4_5_01 -0.0000291890253835816989f
#define SDM_ERFCF4_5_02 0.0000948643324966405230f
#define SDM_ERFCF4_5_03 -0.000195809711948193862f
#define SDM_ERFCF4_5_04 0.000286569337750268210f
#define SDM_ERFCF4_5_05 -0.000313797225490890491f
#define SDM_ERFCF4_5_06 0.000263528504215059911f
#define SDM_ERFCF4_5_07 -0.000169991414511391200f
#define SDM_ERFCF4_5_08 0.0000816476305301353867f
#define SDM_ERFCF4_5_09 -0.0000259138470056606003f
#define SDM_ERFCF4_5_10 2.32886623721087698e-6f
#define SDM_ERFCF4_5_11 2.86429946075621661e-6f
#define SDM_ERFCF4_5_12 0.0f
#define SDM_ERFCF4_5_13 0.0f
#define SDM_ERFCF4_5_14 0.0f
/***************************************************************
* REGION 6:
*/
#define SDM_ERFCF4_6_START 3.45f
#define SDM_ERFCF4_6_OFF 3.625f
#define SDM_ERFCF4_6_TRUNC 1u
#define SDM_ERFCF4_6_00 2.95140192507759025e-7f
#define SDM_ERFCF4_6_01 -2.21592028463311237e-6f
#define SDM_ERFCF4_6_02 8.03271103179503198e-6f
#define SDM_ERFCF4_6_03 -0.0000186737448986269582f
#define SDM_ERFCF4_6_04 0.0000311685922848296785f
#define SDM_ERFCF4_6_05 -0.0000395923353434149457f
#define SDM_ERFCF4_6_06 0.0000395291139306718091f
#define SDM_ERFCF4_6_07 -0.0000315141214892874786f
#define SDM_ERFCF4_6_08 0.0000200891481859513911f
#define SDM_ERFCF4_6_09 -0.0000100551790824327187f
#define SDM_ERFCF4_6_10 3.71860071281680690e-6f
#define SDM_ERFCF4_6_11 -8.05502983594814356e-7f
#define SDM_ERFCF4_6_12 -7.67662978382552699e-8f
#define SDM_ERFCF4_6_13 1.56408548403936681e-7f
#define SDM_ERFCF4_6_14 0.0f
#define SDM_ERFCF4_6_15 0.0f
#define SDM_ERFCF4_6_16 0.0f
#define SDM_ERFCF4_6_17 0.0f
/***************************************************************
* REGION 7:
*/
#define SDM_ERFCF4_7_START 3.55f
#define SDM_ERFCF4_7_OFF 4.0f
#define SDM_ERFCF4_7_TRUNC 2u
#define SDM_ERFCF4_7_00 1.54172579002800189e-8f
#define SDM_ERFCF4_7_01 -1.2698234671866558e-7f
#define SDM_ERFCF4_7_02 5.0792938687466233e-7f
#define SDM_ERFCF4_7_03 -1.3121509160928777e-6f
#define SDM_ERFCF4_7_04 2.4549920365608679e-6f
#define SDM_ERFCF4_7_05 -3.5343419836695254e-6f
#define SDM_ERFCF4_7_06 4.0577914351431357e-6f
#define SDM_ERFCF4_7_07 -3.7959659297660776e-6f
#define SDM_ERFCF4_7_08 2.9264391936639771e-6f
#define SDM_ERFCF4_7_09 -1.8631747969134646e-6f
#define SDM_ERFCF4_7_10 9.702839808793979e-7f
#define SDM_ERFCF4_7_11 -4.0077792841735885e-7f
#define SDM_ERFCF4_7_12 1.2017256123590621e-7f
#define SDM_ERFCF4_7_13 -1.7432381111955779e-8f
#define SDM_ERFCF4_7_14 0.0f
/***************************************************************
* Now we load the description of each partition.
*/
/* Start point for each partition */
vec_float4 r1start = spu_splats(SDM_ERFCF4_1_START);
vec_float4 r2start = spu_splats(SDM_ERFCF4_2_START);
vec_float4 r3start = spu_splats(SDM_ERFCF4_3_START);
vec_float4 r4start = spu_splats(SDM_ERFCF4_4_START);
vec_float4 r5start = spu_splats(SDM_ERFCF4_5_START);
vec_float4 r6start = spu_splats(SDM_ERFCF4_6_START);
vec_float4 r7start = spu_splats(SDM_ERFCF4_7_START);
/* X Offset for each partition */
vec_float4 xoffseta = (vec_float4) {SDM_ERFCF4_0_OFF, SDM_ERFCF4_1_OFF, SDM_ERFCF4_2_OFF, SDM_ERFCF4_3_OFF};
vec_float4 xoffsetb = (vec_float4) {SDM_ERFCF4_4_OFF, SDM_ERFCF4_5_OFF, SDM_ERFCF4_6_OFF, SDM_ERFCF4_7_OFF};
/* Truncation Correction for each partition */
vec_uint4 tcorra = (vec_uint4) {SDM_ERFCF4_0_TRUNC, SDM_ERFCF4_1_TRUNC, SDM_ERFCF4_2_TRUNC, SDM_ERFCF4_3_TRUNC};
vec_uint4 tcorrb = (vec_uint4) {SDM_ERFCF4_4_TRUNC, SDM_ERFCF4_5_TRUNC, SDM_ERFCF4_6_TRUNC, SDM_ERFCF4_7_TRUNC};
/* The coefficients for each partition */
vec_float4 c00a = (vec_float4) {SDM_ERFCF4_0_00, SDM_ERFCF4_1_00, SDM_ERFCF4_2_00, SDM_ERFCF4_3_00};
vec_float4 c01a = (vec_float4) {SDM_ERFCF4_0_01, SDM_ERFCF4_1_01, SDM_ERFCF4_2_01, SDM_ERFCF4_3_01};
vec_float4 c02a = (vec_float4) {SDM_ERFCF4_0_02, SDM_ERFCF4_1_02, SDM_ERFCF4_2_02, SDM_ERFCF4_3_02};
vec_float4 c03a = (vec_float4) {SDM_ERFCF4_0_03, SDM_ERFCF4_1_03, SDM_ERFCF4_2_03, SDM_ERFCF4_3_03};
vec_float4 c04a = (vec_float4) {SDM_ERFCF4_0_04, SDM_ERFCF4_1_04, SDM_ERFCF4_2_04, SDM_ERFCF4_3_04};
vec_float4 c05a = (vec_float4) {SDM_ERFCF4_0_05, SDM_ERFCF4_1_05, SDM_ERFCF4_2_05, SDM_ERFCF4_3_05};
vec_float4 c06a = (vec_float4) {SDM_ERFCF4_0_06, SDM_ERFCF4_1_06, SDM_ERFCF4_2_06, SDM_ERFCF4_3_06};
vec_float4 c07a = (vec_float4) {SDM_ERFCF4_0_07, SDM_ERFCF4_1_07, SDM_ERFCF4_2_07, SDM_ERFCF4_3_07};
vec_float4 c08a = (vec_float4) {SDM_ERFCF4_0_08, SDM_ERFCF4_1_08, SDM_ERFCF4_2_08, SDM_ERFCF4_3_08};
vec_float4 c09a = (vec_float4) {SDM_ERFCF4_0_09, SDM_ERFCF4_1_09, SDM_ERFCF4_2_09, SDM_ERFCF4_3_09};
vec_float4 c10a = (vec_float4) {SDM_ERFCF4_0_10, SDM_ERFCF4_1_10, SDM_ERFCF4_2_10, SDM_ERFCF4_3_10};
vec_float4 c11a = (vec_float4) {SDM_ERFCF4_0_11, SDM_ERFCF4_1_11, SDM_ERFCF4_2_11, SDM_ERFCF4_3_11};
vec_float4 c12a = (vec_float4) {SDM_ERFCF4_0_12, SDM_ERFCF4_1_12, SDM_ERFCF4_2_12, SDM_ERFCF4_3_12};
vec_float4 c13a = (vec_float4) {SDM_ERFCF4_0_13, SDM_ERFCF4_1_13, SDM_ERFCF4_2_13, SDM_ERFCF4_3_13};
vec_float4 c14a = (vec_float4) {SDM_ERFCF4_0_14, SDM_ERFCF4_1_14, SDM_ERFCF4_2_14, SDM_ERFCF4_3_14};
vec_float4 c00b = (vec_float4) {SDM_ERFCF4_4_00, SDM_ERFCF4_5_00, SDM_ERFCF4_6_00, SDM_ERFCF4_7_00};
vec_float4 c01b = (vec_float4) {SDM_ERFCF4_4_01, SDM_ERFCF4_5_01, SDM_ERFCF4_6_01, SDM_ERFCF4_7_01};
vec_float4 c02b = (vec_float4) {SDM_ERFCF4_4_02, SDM_ERFCF4_5_02, SDM_ERFCF4_6_02, SDM_ERFCF4_7_02};
vec_float4 c03b = (vec_float4) {SDM_ERFCF4_4_03, SDM_ERFCF4_5_03, SDM_ERFCF4_6_03, SDM_ERFCF4_7_03};
vec_float4 c04b = (vec_float4) {SDM_ERFCF4_4_04, SDM_ERFCF4_5_04, SDM_ERFCF4_6_04, SDM_ERFCF4_7_04};
vec_float4 c05b = (vec_float4) {SDM_ERFCF4_4_05, SDM_ERFCF4_5_05, SDM_ERFCF4_6_05, SDM_ERFCF4_7_05};
vec_float4 c06b = (vec_float4) {SDM_ERFCF4_4_06, SDM_ERFCF4_5_06, SDM_ERFCF4_6_06, SDM_ERFCF4_7_06};
vec_float4 c07b = (vec_float4) {SDM_ERFCF4_4_07, SDM_ERFCF4_5_07, SDM_ERFCF4_6_07, SDM_ERFCF4_7_07};
vec_float4 c08b = (vec_float4) {SDM_ERFCF4_4_08, SDM_ERFCF4_5_08, SDM_ERFCF4_6_08, SDM_ERFCF4_7_08};
vec_float4 c09b = (vec_float4) {SDM_ERFCF4_4_09, SDM_ERFCF4_5_09, SDM_ERFCF4_6_09, SDM_ERFCF4_7_09};
vec_float4 c10b = (vec_float4) {SDM_ERFCF4_4_10, SDM_ERFCF4_5_10, SDM_ERFCF4_6_10, SDM_ERFCF4_7_10};
vec_float4 c11b = (vec_float4) {SDM_ERFCF4_4_11, SDM_ERFCF4_5_11, SDM_ERFCF4_6_11, SDM_ERFCF4_7_11};
vec_float4 c12b = (vec_float4) {SDM_ERFCF4_4_12, SDM_ERFCF4_5_12, SDM_ERFCF4_6_12, SDM_ERFCF4_7_12};
vec_float4 c13b = (vec_float4) {SDM_ERFCF4_4_13, SDM_ERFCF4_5_13, SDM_ERFCF4_6_13, SDM_ERFCF4_7_13};
vec_float4 c14b = (vec_float4) {SDM_ERFCF4_4_14, SDM_ERFCF4_5_14, SDM_ERFCF4_6_14, SDM_ERFCF4_7_14};
vec_uchar16 shuffle0 = (vec_uchar16) spu_splats(0x00010203);
vec_uchar16 shuffle1 = (vec_uchar16) spu_splats(0x04050607);
vec_uchar16 shuffle2 = (vec_uchar16) spu_splats(0x08090A0B);
vec_uchar16 shuffle3 = (vec_uchar16) spu_splats(0x0C0D0E0F);
vec_uchar16 shuffle4 = (vec_uchar16) spu_splats(0x10111213);
vec_uchar16 shuffle5 = (vec_uchar16) spu_splats(0x14151617);
vec_uchar16 shuffle6 = (vec_uchar16) spu_splats(0x18191A1B);
vec_uchar16 shuffle7 = (vec_uchar16) spu_splats(0x1C1D1E1F);
/*
* Determine the shuffle pattern based on which partition
* each element of x is in.
*/
vec_uchar16 gt_r1start = (vec_uchar16)spu_cmpabsgt(x, r1start);
vec_uchar16 gt_r2start = (vec_uchar16)spu_cmpabsgt(x, r2start);
vec_uchar16 gt_r3start = (vec_uchar16)spu_cmpabsgt(x, r3start);
vec_uchar16 gt_r4start = (vec_uchar16)spu_cmpabsgt(x, r4start);
vec_uchar16 gt_r5start = (vec_uchar16)spu_cmpabsgt(x, r5start);
vec_uchar16 gt_r6start = (vec_uchar16)spu_cmpabsgt(x, r6start);
vec_uchar16 gt_r7start = (vec_uchar16)spu_cmpabsgt(x, r7start);
vec_uchar16 shufflepattern;
shufflepattern = spu_sel(shuffle0, shuffle1, gt_r1start);
shufflepattern = spu_sel(shufflepattern, shuffle2, gt_r2start);
shufflepattern = spu_sel(shufflepattern, shuffle3, gt_r3start);
shufflepattern = spu_sel(shufflepattern, shuffle4, gt_r4start);
shufflepattern = spu_sel(shufflepattern, shuffle5, gt_r5start);
shufflepattern = spu_sel(shufflepattern, shuffle6, gt_r6start);
shufflepattern = spu_sel(shufflepattern, shuffle7, gt_r7start);
/* Use the shuffle pattern to select the coefficients */
vec_float4 coeff_14 = spu_shuffle(c14a, c14b, shufflepattern);
vec_float4 coeff_13 = spu_shuffle(c13a, c13b, shufflepattern);
vec_float4 coeff_12 = spu_shuffle(c12a, c12b, shufflepattern);
vec_float4 coeff_11 = spu_shuffle(c11a, c11b, shufflepattern);
vec_float4 coeff_10 = spu_shuffle(c10a, c10b, shufflepattern);
vec_float4 coeff_09 = spu_shuffle(c09a, c09b, shufflepattern);
vec_float4 coeff_08 = spu_shuffle(c08a, c08b, shufflepattern);
vec_float4 coeff_07 = spu_shuffle(c07a, c07b, shufflepattern);
vec_float4 coeff_06 = spu_shuffle(c06a, c06b, shufflepattern);
vec_float4 coeff_05 = spu_shuffle(c05a, c05b, shufflepattern);
vec_float4 coeff_04 = spu_shuffle(c04a, c04b, shufflepattern);
vec_float4 coeff_03 = spu_shuffle(c03a, c03b, shufflepattern);
vec_float4 coeff_02 = spu_shuffle(c02a, c02b, shufflepattern);
vec_float4 coeff_01 = spu_shuffle(c01a, c01b, shufflepattern);
vec_float4 coeff_00 = spu_shuffle(c00a, c00b, shufflepattern);
vec_float4 xoffset = spu_shuffle(xoffseta, xoffsetb, shufflepattern);
vec_uint4 tcorrection = spu_shuffle(tcorra, tcorrb, shufflepattern);
/*
* We've completed the coeff. setup. Now we actually do the
* approximation below.
*/
/* Adjust x value here (for approximations about a point) */
vec_float4 xappr = spu_sub(xabs, xoffset);
/* Now we do the multiplies.
* Use Horner's method.
*/
result = coeff_14;
result = spu_madd(xappr, result, coeff_13);
result = spu_madd(xappr, result, coeff_12);
result = spu_madd(xappr, result, coeff_11);
result = spu_madd(xappr, result, coeff_10);
result = spu_madd(xappr, result, coeff_09);
result = spu_madd(xappr, result, coeff_08);
result = spu_madd(xappr, result, coeff_07);
result = spu_madd(xappr, result, coeff_06);
result = spu_madd(xappr, result, coeff_05);
result = spu_madd(xappr, result, coeff_04);
result = spu_madd(xappr, result, coeff_03);
result = spu_madd(xappr, result, coeff_02);
result = spu_madd(xappr, result, coeff_01);
result = spu_madd(xappr, result, coeff_00);
/* Adjust due to systematic truncation. */
result = (vec_float4)spu_add((vec_uint4)result, tcorrection);
/* Use the continued fraction approximation for x above approx. 4
* and below approx. 10
*/
vec_float4 presult, xsqu;
xsqu = spu_mul(x, x); xsqu = spu_mul(x, x);
/*
* Use Taylor Series for x near 0
* Preserve sign of x in result, since erf(-x) = -erf(x)
* This approximation is for erf, so adjust for erfc.
*/
TAYLOR_ERFF4(xabs, xsqu, tresult);
tresult = spu_or(tresult, xsign);
tresult = spu_sub(onef, tresult);
/*
* Now, use the Continued Fractions approximation away
* from 0. If x < 0, use erfc(-x) = 2 - erfc(x)
*/
CONTFRAC_ERFCF4(xabs, xsqu, presult); CONTFRAC_ERFCF4(xabs, xsqu, presult);
isneg = spu_rlmaska((vec_uint4)x, -32);
presult = spu_sel(presult, spu_sub(twof, presult), isneg);
/* /* Select between polynomial and continued fraction */
* Select the appropriate approximation. result = spu_sel(presult, result, spu_cmpgt(spu_splats(4.3f), xabs));
*/
result = spu_sel(tresult, presult, spu_cmpgt(xabs, approx_point));
/* /* Above clamp value, set erfc = 0 */
* Special cases/errors. result = spu_sel(result, zerof, spu_cmpgt(xabs, clamp));
*/
/* x = +/- infinite */ /* Negative x values */
result = spu_sel(result, zerof, spu_cmpeq((vec_uint4)xabs, 0x7F800000)); vec_uint4 gt0 = spu_cmpgt(x, zerof);
result = spu_sel(result, twof, spu_cmpeq((vec_uint4)xabs, 0xFF800000)); result = spu_sel(spu_sub(twof, result), result, gt0);
return result; return result;
} }

View File

@ -68,7 +68,6 @@ static __inline vector double _erfd2(vector double x)
{ {
vec_uchar16 dup_even = ((vec_uchar16) { 0,1,2,3, 0,1,2,3, 8, 9,10,11, 8, 9,10,11 }); vec_uchar16 dup_even = ((vec_uchar16) { 0,1,2,3, 0,1,2,3, 8, 9,10,11, 8, 9,10,11 });
vec_double2 onehalfd = spu_splats(0.5); vec_double2 onehalfd = spu_splats(0.5);
vec_double2 zerod = spu_splats(0.0);
vec_double2 oned = spu_splats(1.0); vec_double2 oned = spu_splats(1.0);
vec_double2 sign_mask = spu_splats(-0.0); vec_double2 sign_mask = spu_splats(-0.0);
@ -76,15 +75,9 @@ static __inline vector double _erfd2(vector double x)
vec_float4 approx_point = spu_splats(1.77f); vec_float4 approx_point = spu_splats(1.77f);
vec_double2 xabs, xsqu, xsign; vec_double2 xabs, xsqu, xsign;
vec_uint4 xabshigh;
vec_uint4 isinf, isnan;
vec_double2 tresult, presult, result; vec_double2 tresult, presult, result;
xsign = spu_and(x, sign_mask); xsign = spu_and(x, sign_mask);
/* Force Denorms to 0 */
x = spu_add(x, zerod);
xabs = spu_andc(x, sign_mask); xabs = spu_andc(x, sign_mask);
xsqu = spu_mul(x, x); xsqu = spu_mul(x, x);
@ -112,15 +105,11 @@ static __inline vector double _erfd2(vector double x)
/* /*
* Special cases/errors. * Special cases/errors.
*/ */
xabshigh = (vec_uint4)spu_shuffle(xabs, xabs, dup_even);
/* x = +/- infinite, return +/-1 */ /* x = +/- infinite, return +/-1 */
isinf = spu_cmpeq(xabshigh, 0x7FF00000);
result = spu_sel(result, oned, (vec_ullong2)isinf);
/* x = nan, return x */ /* x = nan, return x */
isnan = spu_cmpgt(xabshigh, 0x7FF00000); result = spu_sel(result, oned, spu_testsv(x, SPU_SV_NEG_INFINITY | SPU_SV_POS_INFINITY));
result = spu_sel(result, x, (vec_ullong2)isnan); result = spu_sel(result, x, spu_testsv(x, SPU_SV_NEG_DENORM | SPU_SV_POS_DENORM));
/* /*
* Preserve sign in result, since erf(-x) = -erf(x) * Preserve sign in result, since erf(-x) = -erf(x)

View File

@ -62,49 +62,104 @@
* preicision result. * preicision result.
* *
* The Newton-Raphson iteration is of the form: * The Newton-Raphson iteration is of the form:
* X[i+1] = X[i] * (2.0 - b*X[i]) * a) X[i+1] = X[i] * (2.0 - b*X[i])
* or
* b) X[i+1] = X[i] + X[i]*(1.0 - X[i]*b)
* where b is the input value to be inverted * where b is the input value to be inverted
* *
* The later (b) form improves the accuracy to 99.95% correctly rounded.
*/ */
static __inline vector double _recipd2(vector double value_d) static __inline vector double _recipd2(vector double value_in)
{ {
vector unsigned long long expmask = (vector unsigned long long) { 0x7FF0000000000000ULL, 0x7FF0000000000000ULL }; vec_float4 x0;
vector float x0; vec_float4 value;
vector float value; vec_float4 one = spu_splats(1.0f);
vector float two = spu_splats(2.0f); vec_double2 one_d = spu_splats(1.0);
vector double two_d = spu_splats(2.0); vec_double2 x1, x2, x3;
vector double x1, x2, x3; vec_double2 scale;
vector double bias; vec_double2 exp, value_d;
vec_ullong2 expmask = spu_splats(0x7FF0000000000000ULL);
/* Bias the divisor to correct for double precision floating vec_ullong2 is0inf;
* point exponents that are out of single precision range.
*/
bias = spu_xor(spu_and(value_d, (vector double)expmask), (vector double)expmask);
value = spu_roundtf(spu_mul(value_d, bias));
x0 = spu_re(value);
x1 = spu_extend(spu_mul(x0, spu_nmsub(value, x0, two)));
x1 = spu_mul(x1, bias);
x2 = spu_mul(x1, spu_nmsub(value_d, x1, two_d));
x3 = spu_mul(x2, spu_nmsub(value_d, x2, two_d));
/* Handle input = +/- infinity or +/-0. */
#ifdef __SPU_EDP__ #ifdef __SPU_EDP__
vec_ullong2 is0inf = spu_testsv(value_d, SPU_SV_NEG_ZERO | SPU_SV_POS_ZERO | vec_ullong2 isdenorm;
SPU_SV_NEG_INFINITY | SPU_SV_POS_INFINITY); vec_ullong2 expmask_minus1 = spu_splats(0x7FE0000000000000ULL);
#else
vec_double2 nzero = spu_splats(-0.0); /* Determine special input values. For example, if the input is a denorm, infinity or 0 */
vec_double2 xabs = spu_andc(value_d, nzero);
vector unsigned char swap = (vector unsigned char) {4,5,6,7, 0,1,2,3, 12,13,14,15, 8,9,10,11}; isdenorm = spu_testsv(value_in, (SPU_SV_POS_DENORM | SPU_SV_NEG_DENORM));
vec_uint4 isinf = spu_cmpeq((vec_uint4)xabs, (vec_uint4)expmask); is0inf = spu_testsv(value_in, (SPU_SV_NEG_ZERO | SPU_SV_POS_ZERO |
vec_uint4 iszero = spu_cmpeq((vec_uint4)xabs, 0); SPU_SV_NEG_INFINITY | SPU_SV_POS_INFINITY));
/* Scale the divisor to correct for double precision floating
* point exponents that are out of single precision range.
*/
exp = spu_and(value_in, (vec_double2)expmask);
scale = spu_xor(exp, (vec_double2)spu_sel(expmask, expmask_minus1, isdenorm));
value_d = spu_mul(value_in, scale);
value = spu_roundtf(value_d);
/* Perform reciprocal with 1 single precision and 2 double precision
* Newton-Raphson iterations.
*/
x0 = spu_re(value);
x1 = spu_extend(spu_madd(spu_nmsub(value, x0, one), x0, x0));
x2 = spu_madd(spu_nmsub(value_d, x1, one_d), x1, x1);
x3 = spu_madd(spu_nmsub(value_d, x2, one_d), x2, x2);
x3 = spu_sel(spu_mul(x3, scale), spu_xor(value_in, (vector double)expmask), is0inf);
#else /* !__SPU_EDP__ */
vec_uint4 isinf, iszero, isdenorm0;
vec_double2 value_abs;
vec_double2 sign = spu_splats(-0.0);
vec_double2 denorm_scale = (vec_double2)spu_splats(0x4330000000000000ULL);
vec_double2 exp_53 = (vec_double2)spu_splats(0x0350000000000000ULL);
vec_uchar16 splat_hi = (vec_uchar16){0,1,2,3, 0,1,2,3, 8,9,10,11, 8,9,10,11};
vec_uchar16 swap = (vec_uchar16){4,5,6,7, 0,1,2,3, 12,13,14,15, 8,9,10,11};
value_abs = spu_andc(value_in, sign);
exp = spu_and(value_in, (vec_double2)expmask);
/* Determine if the input is a special value. These include:
* denorm - then we must coerce it to a normal value.
* zero - then we must return an infinity
* infinity - then we must return a zero.
*/
isdenorm0 = spu_cmpeq(spu_shuffle((vec_uint4)exp, (vec_uint4)exp, splat_hi), 0);
isinf = spu_cmpeq((vec_uint4)value_abs, (vec_uint4)expmask);
iszero = spu_cmpeq((vec_uint4)value_abs, 0);
isinf = spu_and(isinf, spu_shuffle(isinf, isinf, swap)); isinf = spu_and(isinf, spu_shuffle(isinf, isinf, swap));
iszero = spu_and(iszero, spu_shuffle(iszero, iszero, swap)); iszero = spu_and(iszero, spu_shuffle(iszero, iszero, swap));
vec_ullong2 is0inf = (vec_ullong2)spu_or(isinf, iszero); is0inf = (vec_ullong2)spu_or(isinf, iszero);
#endif /* __SPU_EDP__ */
x3 = spu_sel(x3, spu_xor(value_d, (vector double)expmask), is0inf); /* If the inputs is a denorm, we must first convert it to a normal number since
* arithmetic operations on denormals produces 0 on Cell/B.E.
*/
value_d = spu_sub(spu_or(value_abs, exp_53), exp_53);
value_d = spu_sel(value_abs, value_d, (vec_ullong2)isdenorm0);
/* Scale the divisor to correct for double precision floating
* point exponents that are out of single precision range.
*/
scale = spu_xor(spu_and(value_d, (vec_double2)expmask), (vec_double2)expmask);
value_d = spu_mul(value_d, scale);
value = spu_roundtf(value_d);
/* Perform reciprocal with 1 single precision and 2 double precision
* Newton-Raphson iterations. The bias is removed after the single
* precision iteration.
*/
x0 = spu_re(value);
x1 = spu_extend(spu_madd(spu_nmsub(value, x0, one), x0, x0));
x2 = spu_madd(spu_nmsub(value_d, x1, one_d), x1, x1);
x3 = spu_madd(spu_nmsub(value_d, x2, one_d), x2, x2);
x3 = spu_mul(x3, spu_sel(scale, value_in, (vec_ullong2)sign));
x3 = spu_sel(x3, spu_mul(x3, denorm_scale), (vec_ullong2)isdenorm0);
x3 = spu_sel(x3, spu_xor(value_in, (vector double)expmask), is0inf);
#endif /* __SPU_EDP__ */
return (x3); return (x3);
} }