From 4b2d8e4442745a09f24804c1fcc97b7c5c4506f1 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Wed, 8 Apr 2020 17:42:46 -0300 Subject: [PATCH] i386: Use generic exp10f The generic implementation is twice as fast. Using the exp10f benchmark: * master: "exp10f": { "workload-spec2017.wrf (adapted)": { "duration": 1.02967e+09, "iterations": 4.768e+07, "reciprocal-throughput": 18.3579, "latency": 24.8331, "max-throughput": 5.44725e+07, "min-throughput": 4.02688e+07 } } * patched: "exp10f": { "workload-spec2017.wrf (adapted)": { "duration": 1.01821e+09, "iterations": 6.1984e+07, "reciprocal-throughput": 13.1975, "latency": 19.6563, "max-throughput": 7.57719e+07, "min-throughput": 5.08743e+07 } } Checked on i686-linux-gnu. --- sysdeps/i386/fpu/e_exp10f.S | 54 ------------------------------------- 1 file changed, 54 deletions(-) delete mode 100644 sysdeps/i386/fpu/e_exp10f.S diff --git a/sysdeps/i386/fpu/e_exp10f.S b/sysdeps/i386/fpu/e_exp10f.S deleted file mode 100644 index 196ce8744a0..00000000000 --- a/sysdeps/i386/fpu/e_exp10f.S +++ /dev/null @@ -1,54 +0,0 @@ -/* - * Written by Ulrich Drepper. - */ - -#include -#include -#include - -DEFINE_FLT_MIN - -#ifdef PIC -# define MO(op) op##@GOTOFF(%ecx) -#else -# define MO(op) op -#endif - - .text -/* 10^x = 2^(x * log2(10)) */ -ENTRY(__ieee754_exp10f) -#ifdef PIC - LOAD_PIC_REG (cx) -#endif - flds 4(%esp) -/* I added the following ugly construct because exp(+-Inf) resulted - in NaN. The ugliness results from the bright minds at Intel. - For the i686 the code can be written better. - -- drepper@cygnus.com. */ - fxam /* Is NaN or +-Inf? */ - fstsw %ax - movb $0x45, %dh - andb %ah, %dh - cmpb $0x05, %dh - je 1f /* Is +-Inf, jump. */ - fldl2t - fmulp /* x * log2(10) */ - fld %st - frndint /* int(x * log2(10)) */ - fsubr %st,%st(1) /* fract(x * log2(10)) */ - fxch - f2xm1 /* 2^(fract(x * log2(10))) - 1 */ - fld1 - faddp /* 2^(fract(x * log2(10))) */ - fscale /* e^x */ - fstp %st(1) - FLT_NARROW_EVAL_UFLOW_NONNEG_NAN - ret - -1: testl $0x200, %eax /* Test sign. */ - jz 2f /* If positive, jump. */ - fstp %st - fldz /* Set result to 0. */ -2: ret -END (__ieee754_exp10f) -libm_alias_finite (__ieee754_exp10f, __exp10f) -- 2.39.5