mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 08:40:07 +00:00
b2a64460ba
This patch refactors code in sysdeps/x86_64/fpu that forces underflow exceptions and closely follows corresponding i386 code to use common macros in x86_64-math-asm.h for that purpose. This is mainly about keeping the code similar to the i386 code as far as possible, since each macro apart from DEFINE_LDBL_MIN ends up used only once. It would be possible to do a further refactoring to share these macros between i386 and x86_64 (with i386 using the fcomip / fucomip versions when building for i686 and above), but I have no immediate plans to do so. Tested for x86_64. * sysdeps/x86_64/fpu/x86_64-math-asm.h: New file. * sysdeps/x86_64/fpu/e_exp2l.S: Include <x86_64-math-asm.h>. (ldbl_min): Replace with use of DEFINE_LDBL_MIN. (__ieee754_exp2l): Use LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN. * sysdeps/x86_64/fpu/e_expl.S: Include <x86_64-math-asm.h>. [!USE_AS_EXPM1L] (cmin): Replace with use of DEFINE_LDBL_MIN. (IEEE754_EXPL): Use LDBL_CHECK_FORCE_UFLOW_NONNEG.
59 lines
1.2 KiB
ArmAsm
59 lines
1.2 KiB
ArmAsm
/*
|
|
* Written by J.T. Conklin <jtc@netbsd.org>.
|
|
* Adapted for exp2 by Ulrich Drepper <drepper@cygnus.com>.
|
|
* Adapted for x86-64 by Andreas Jaeger <aj@suse.de>.
|
|
* Public domain.
|
|
*/
|
|
|
|
#include <machine/asm.h>
|
|
#include <x86_64-math-asm.h>
|
|
|
|
DEFINE_LDBL_MIN
|
|
|
|
#ifdef PIC
|
|
# define MO(op) op##(%rip)
|
|
#else
|
|
# define MO(op) op
|
|
#endif
|
|
|
|
.text
|
|
ENTRY(__ieee754_exp2l)
|
|
fldt 8(%rsp)
|
|
/* 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. */
|
|
movzwl 8+8(%rsp), %eax
|
|
andl $0x7fff, %eax
|
|
cmpl $0x3fbe, %eax
|
|
jge 3f
|
|
/* Argument's exponent below -65, result rounds to 1. */
|
|
fld1
|
|
faddp
|
|
ret
|
|
3: fld %st
|
|
frndint /* int(x) */
|
|
fsubr %st,%st(1) /* fract(x) */
|
|
fxch
|
|
f2xm1 /* 2^(fract(x)) - 1 */
|
|
fld1
|
|
faddp /* 2^(fract(x)) */
|
|
fscale /* e^x */
|
|
fstp %st(1)
|
|
LDBL_CHECK_FORCE_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_exp2l)
|
|
strong_alias (__ieee754_exp2l, __exp2l_finite)
|