glibc/sysdeps/i386/fpu/i386-math-asm.h

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/* Helper macros for x86 libm functions.
Copyright (C) 2015-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _I386_MATH_ASM_H
#define _I386_MATH_ASM_H 1
/* Remove excess range and precision by storing a value on the stack
and loading it back. */
#define FLT_NARROW_EVAL \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fstps (%esp); \
flds (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4);
#define DBL_NARROW_EVAL \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fstpl (%esp); \
fldl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8);
Avoid excess range in results from i386 exp, hypot, pow functions (bug 18980). i386 exp, hypot and pow functions can return overflowing and underflowing values with excess range and precision; ; Wilco Dijkstra's patches to make isfinite etc. expand inline cause this pre-existing issue to result in test failures. This patch fixes those functions to avoid excess range and precision in their return values. Appropriate macros are added for the repeated code sequences; in future I'll add more such macros and refactor existing code forcing underflow (with or without also eliminating excess range and precision from the return value) to use such macros. Tested for x86. If, after this patch, you still see x86 libm test failures with excess range or precision, please file bugs in Bugzilla. [BZ #18980] * sysdeps/i386/fpu/i386-math-asm.h (DEFINE_FLT_MIN): New macro. (DEFINE_DBL_MIN): Likewise. (FLT_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise. (DBL_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise. (FLT_NARROW_EVAL_UFLOW_NONNEG): Likewise. (DBL_NARROW_EVAL_UFLOW_NONNEG): Likewise. * sysdeps/i386/fpu/e_exp.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. (__exp_finite): Use DBL_NARROW_EVAL_UFLOW_NONNEG. * sysdeps/i386/fpu/e_exp10.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp10): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp10f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_exp10f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp2.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp2): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp2f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_exp2f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_expf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_expf): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. (__expf_finite): Use FLT_NARROW_EVAL_UFLOW_NONNEG. * sysdeps/i386/fpu/e_hypot.S: Include <i386-math-asm.h>. (__ieee754_hypot): Use DBL_NARROW_EVAL. * sysdeps/i386/fpu/e_hypotf.S: Include <i386-math-asm.h>. (__ieee754_hypotf): Use FLT_NARROW_EVAL. * sysdeps/i386/fpu/e_pow.S: Include <i386-math-asm.h>. (__ieee754_pow): Use DBL_NARROW_EVAL. * sysdeps/i386/fpu/e_powf.S: Include <i386-math-asm.h>. (__ieee754_powf): Use FLT_NARROW_EVAL. * sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S (__ieee754_expf_sse2): Convert double-precision result to single precision. * sysdeps/i386/fpu/libm-test-ulps: Update.
2015-09-18 21:53:22 +00:00
/* Define constants for the minimum value of a floating-point
type. */
#define DEFINE_FLT_MIN \
.section .rodata.cst4,"aM",@progbits,4; \
.p2align 2; \
.type flt_min,@object; \
flt_min: \
.byte 0, 0, 0x80, 0; \
.size flt_min, .-flt_min;
#define DEFINE_DBL_MIN \
.section .rodata.cst8,"aM",@progbits,8; \
.p2align 3; \
.type dbl_min,@object; \
dbl_min: \
.byte 0, 0, 0, 0, 0, 0, 0x10, 0; \
.size dbl_min, .-dbl_min;
Refactor i386 libm code forcing underflow exceptions. This patch refactors code in sysdeps/i386/fpu that forces underflow exceptions to use common macros for that purpose as far as possible. (Although some of the macros end up used in only one place, I think it's cleanest to define all these macros together so that all the code forcing underflow uses such macros. Some more uses of such macros will also be introduced when fixing remaining bugs about missing underflow exceptions, and it would be possible to do further refactoring of the macros in i386-math-asm.h to share more code by using other macros internally. Places that test for underflow by examining the representation of the argument with integer operations, rather that using floating-point comparisons on the argument or result, are unchanged by this patch.) Most of this code uses a macro MO to abstract away the differences between PIC and non-PIC memory references to constants. log1p functions, however, hardcoded PIC conditionals for this. Because the common macros rely on the use of MO, I changed the log1p functions to use the normal style here, and, for consistency, also made that change to log1pl which is otherwise unaffected by this patch. Tested for x86. * sysdeps/i386/fpu/i386-math-asm.h (DEFINE_LDBL_MIN): New macro. (FLT_CHECK_FORCE_UFLOW): Likewise. (DBL_CHECK_FORCE_UFLOW): Likewise. (FLT_CHECK_FORCE_UFLOW_NARROW): Likewise. (DBL_CHECK_FORCE_UFLOW_NARROW): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNAN): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNEG): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. * sysdeps/i386/fpu/e_asin.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_asin): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_asinf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_asinf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_atan2.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atan2): Use DBL_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atan2f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atan2f): Use FLT_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atanh.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atanh): Use DBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_atanhf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atanhf): Use FLT_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_exp2l.S: Include <i386-math-asm.h>. (ldbl_min): Replace with use of DEFINE_LDBL_MIN. (__ieee754_exp2l): Use LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_expl.S: Include <i386-math-asm.h>. [!USE_AS_EXPM1L] (cmin): Replace with use of DEFINE_LDBL_MIN. (IEEE754_EXPL): Use LDBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/s_atan.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__atan): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_atanf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__atanf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_expm1.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__expm1): Use DBL_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_expm1f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__expm1f): Use FLT_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_log1p.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (MO): New macro. (__log1p): Use MO. Use DBL_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (MO): New macro. (__log1pf): Use MO. Use FLT_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pl.S (MO): New macro. (__log1pl): Use MO.
2015-09-24 21:41:00 +00:00
#define DEFINE_LDBL_MIN \
.section .rodata.cst16,"aM",@progbits,16; \
.p2align 4; \
.type ldbl_min,@object; \
ldbl_min: \
.byte 0, 0, 0, 0, 0, 0, 0, 0x80, 0x1, 0; \
.byte 0, 0, 0, 0, 0, 0; \
.size ldbl_min, .-ldbl_min;
Avoid excess range in results from i386 exp, hypot, pow functions (bug 18980). i386 exp, hypot and pow functions can return overflowing and underflowing values with excess range and precision; ; Wilco Dijkstra's patches to make isfinite etc. expand inline cause this pre-existing issue to result in test failures. This patch fixes those functions to avoid excess range and precision in their return values. Appropriate macros are added for the repeated code sequences; in future I'll add more such macros and refactor existing code forcing underflow (with or without also eliminating excess range and precision from the return value) to use such macros. Tested for x86. If, after this patch, you still see x86 libm test failures with excess range or precision, please file bugs in Bugzilla. [BZ #18980] * sysdeps/i386/fpu/i386-math-asm.h (DEFINE_FLT_MIN): New macro. (DEFINE_DBL_MIN): Likewise. (FLT_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise. (DBL_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise. (FLT_NARROW_EVAL_UFLOW_NONNEG): Likewise. (DBL_NARROW_EVAL_UFLOW_NONNEG): Likewise. * sysdeps/i386/fpu/e_exp.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. (__exp_finite): Use DBL_NARROW_EVAL_UFLOW_NONNEG. * sysdeps/i386/fpu/e_exp10.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp10): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp10f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_exp10f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp2.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_exp2): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_exp2f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_exp2f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_expf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_expf): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN. (__expf_finite): Use FLT_NARROW_EVAL_UFLOW_NONNEG. * sysdeps/i386/fpu/e_hypot.S: Include <i386-math-asm.h>. (__ieee754_hypot): Use DBL_NARROW_EVAL. * sysdeps/i386/fpu/e_hypotf.S: Include <i386-math-asm.h>. (__ieee754_hypotf): Use FLT_NARROW_EVAL. * sysdeps/i386/fpu/e_pow.S: Include <i386-math-asm.h>. (__ieee754_pow): Use DBL_NARROW_EVAL. * sysdeps/i386/fpu/e_powf.S: Include <i386-math-asm.h>. (__ieee754_powf): Use FLT_NARROW_EVAL. * sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S (__ieee754_expf_sse2): Convert double-precision result to single precision. * sysdeps/i386/fpu/libm-test-ulps: Update.
2015-09-18 21:53:22 +00:00
/* Remove excess range and precision by storing a value on the stack
and loading it back. The value is given to be nonnegative or NaN;
if it is subnormal, also force an underflow exception. The
relevant constant for the minimum of the type must have been
defined, the MO macro must have been defined for access to memory
operands, and, if PIC, the PIC register must have been loaded. */
#define FLT_NARROW_EVAL_UFLOW_NONNEG_NAN \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
flds MO(flt_min); \
fld %st(1); \
fucompp; \
fnstsw; \
sahf; \
jnc 6424f; \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
6424: fstps (%esp); \
flds (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4);
#define DBL_NARROW_EVAL_UFLOW_NONNEG_NAN \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fldl MO(dbl_min); \
fld %st(1); \
fucompp; \
fnstsw; \
sahf; \
jnc 6453f; \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
6453: fstpl (%esp); \
fldl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8);
/* Likewise, but the argument is not a NaN (so fcom instructions,
which support memory operands, can be used). */
#define FLT_NARROW_EVAL_UFLOW_NONNEG \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fcoms MO(flt_min); \
fnstsw; \
sahf; \
jnc 6424f; \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
6424: fstps (%esp); \
flds (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4);
#define DBL_NARROW_EVAL_UFLOW_NONNEG \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fcoml MO(dbl_min); \
fnstsw; \
sahf; \
jnc 6453f; \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
6453: fstpl (%esp); \
fldl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8);
Fix pow missing underflows (bug 18825). Similar to various other bugs in this area, pow functions can fail to raise the underflow exception when the result is tiny and inexact but one or more low bits of the intermediate result that is scaled down (or, in the i386 case, converted from a wider evaluation format) are zero. This patch forces the exception in a similar way to previous fixes, thereby concluding the fixes for known bugs with missing underflow exceptions currently filed in Bugzilla. Tested for x86_64, x86, mips64 and powerpc. [BZ #18825] * sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN): New macro. (DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. * sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN. (__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of DBL_NARROW_EVAL, reloading the PIC register as needed. * sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN. (__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of FLT_NARROW_EVAL. Use separate return path for case when first argument is NaN. * sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the PIC register. * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use math_check_force_underflow_nonneg. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force underflow for subnormal result. * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use math_check_force_underflow_nonneg. * sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use math_check_force_underflow. * sysdeps/x86_64/fpu/x86_64-math-asm.h (LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro. * sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN. * math/auto-libm-test-in: Add more tests of pow. * math/auto-libm-test-out: Regenerated.
2015-09-25 22:29:10 +00:00
/* Likewise, but the non-NaN argument may be negative. */
#define FLT_NARROW_EVAL_UFLOW_NONNAN \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fld %st(0); \
fabs; \
fcomps MO(flt_min); \
fnstsw; \
sahf; \
jnc 6424f; \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
6424: fstps (%esp); \
flds (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4);
#define DBL_NARROW_EVAL_UFLOW_NONNAN \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fld %st(0); \
fabs; \
fcompl MO(dbl_min); \
fnstsw; \
sahf; \
jnc 6453f; \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
6453: fstpl (%esp); \
fldl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8);
Refactor i386 libm code forcing underflow exceptions. This patch refactors code in sysdeps/i386/fpu that forces underflow exceptions to use common macros for that purpose as far as possible. (Although some of the macros end up used in only one place, I think it's cleanest to define all these macros together so that all the code forcing underflow uses such macros. Some more uses of such macros will also be introduced when fixing remaining bugs about missing underflow exceptions, and it would be possible to do further refactoring of the macros in i386-math-asm.h to share more code by using other macros internally. Places that test for underflow by examining the representation of the argument with integer operations, rather that using floating-point comparisons on the argument or result, are unchanged by this patch.) Most of this code uses a macro MO to abstract away the differences between PIC and non-PIC memory references to constants. log1p functions, however, hardcoded PIC conditionals for this. Because the common macros rely on the use of MO, I changed the log1p functions to use the normal style here, and, for consistency, also made that change to log1pl which is otherwise unaffected by this patch. Tested for x86. * sysdeps/i386/fpu/i386-math-asm.h (DEFINE_LDBL_MIN): New macro. (FLT_CHECK_FORCE_UFLOW): Likewise. (DBL_CHECK_FORCE_UFLOW): Likewise. (FLT_CHECK_FORCE_UFLOW_NARROW): Likewise. (DBL_CHECK_FORCE_UFLOW_NARROW): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNAN): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNEG): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. * sysdeps/i386/fpu/e_asin.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_asin): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_asinf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_asinf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_atan2.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atan2): Use DBL_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atan2f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atan2f): Use FLT_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atanh.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atanh): Use DBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_atanhf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atanhf): Use FLT_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_exp2l.S: Include <i386-math-asm.h>. (ldbl_min): Replace with use of DEFINE_LDBL_MIN. (__ieee754_exp2l): Use LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_expl.S: Include <i386-math-asm.h>. [!USE_AS_EXPM1L] (cmin): Replace with use of DEFINE_LDBL_MIN. (IEEE754_EXPL): Use LDBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/s_atan.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__atan): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_atanf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__atanf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_expm1.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__expm1): Use DBL_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_expm1f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__expm1f): Use FLT_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_log1p.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (MO): New macro. (__log1p): Use MO. Use DBL_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (MO): New macro. (__log1pf): Use MO. Use FLT_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pl.S (MO): New macro. (__log1pl): Use MO.
2015-09-24 21:41:00 +00:00
/* Force an underflow exception if the given value is subnormal. The
relevant constant for the minimum of the type must have been
defined, the MO macro must have been defined for access to memory
operands, and, if PIC, the PIC register must have been loaded. */
#define FLT_CHECK_FORCE_UFLOW \
flds MO(flt_min); \
fld %st(1); \
fabs; \
fucompp; \
fnstsw; \
sahf; \
jnc 6424f; \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4); \
6424:
#define DBL_CHECK_FORCE_UFLOW \
fldl MO(dbl_min); \
fld %st(1); \
fabs; \
fucompp; \
fnstsw; \
sahf; \
jnc 6453f; \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8); \
6453:
/* Likewise, but also remove excess range and precision if the value
is subnormal. */
#define FLT_CHECK_FORCE_UFLOW_NARROW \
flds MO(flt_min); \
fld %st(1); \
fabs; \
fucompp; \
fnstsw; \
sahf; \
jnc 6424f; \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
fstps (%esp); \
flds (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4); \
6424:
#define DBL_CHECK_FORCE_UFLOW_NARROW \
fldl MO(dbl_min); \
fld %st(1); \
fabs; \
fucompp; \
fnstsw; \
sahf; \
jnc 6453f; \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
fstpl (%esp); \
fldl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8); \
6453:
/* Likewise, but the argument is nonnegative or NaN. */
#define LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN \
fldt MO(ldbl_min); \
fld %st(1); \
fucompp; \
fnstsw; \
sahf; \
jnc 6464f; \
fld %st(0); \
fmul %st(0); \
fstp %st(0); \
6464:
/* Likewise, but the argument is not a NaN. */
#define FLT_CHECK_FORCE_UFLOW_NONNAN \
fld %st(0); \
fabs; \
fcomps MO(flt_min); \
fnstsw; \
sahf; \
jnc 6424f; \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4); \
6424:
#define DBL_CHECK_FORCE_UFLOW_NONNAN \
fld %st(0); \
fabs; \
fcompl MO(dbl_min); \
fnstsw; \
sahf; \
jnc 6453f; \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8); \
6453:
Fix pow missing underflows (bug 18825). Similar to various other bugs in this area, pow functions can fail to raise the underflow exception when the result is tiny and inexact but one or more low bits of the intermediate result that is scaled down (or, in the i386 case, converted from a wider evaluation format) are zero. This patch forces the exception in a similar way to previous fixes, thereby concluding the fixes for known bugs with missing underflow exceptions currently filed in Bugzilla. Tested for x86_64, x86, mips64 and powerpc. [BZ #18825] * sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN): New macro. (DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. * sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN. (__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of DBL_NARROW_EVAL, reloading the PIC register as needed. * sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN. (__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of FLT_NARROW_EVAL. Use separate return path for case when first argument is NaN. * sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the PIC register. * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use math_check_force_underflow_nonneg. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force underflow for subnormal result. * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use math_check_force_underflow_nonneg. * sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use math_check_force_underflow. * sysdeps/x86_64/fpu/x86_64-math-asm.h (LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro. * sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN. * math/auto-libm-test-in: Add more tests of pow. * math/auto-libm-test-out: Regenerated.
2015-09-25 22:29:10 +00:00
#define LDBL_CHECK_FORCE_UFLOW_NONNAN \
fldt MO(ldbl_min); \
fld %st(1); \
fabs; \
fcompp; \
fnstsw; \
sahf; \
jnc 6464f; \
fld %st(0); \
fmul %st(0); \
fstp %st(0); \
6464:
Refactor i386 libm code forcing underflow exceptions. This patch refactors code in sysdeps/i386/fpu that forces underflow exceptions to use common macros for that purpose as far as possible. (Although some of the macros end up used in only one place, I think it's cleanest to define all these macros together so that all the code forcing underflow uses such macros. Some more uses of such macros will also be introduced when fixing remaining bugs about missing underflow exceptions, and it would be possible to do further refactoring of the macros in i386-math-asm.h to share more code by using other macros internally. Places that test for underflow by examining the representation of the argument with integer operations, rather that using floating-point comparisons on the argument or result, are unchanged by this patch.) Most of this code uses a macro MO to abstract away the differences between PIC and non-PIC memory references to constants. log1p functions, however, hardcoded PIC conditionals for this. Because the common macros rely on the use of MO, I changed the log1p functions to use the normal style here, and, for consistency, also made that change to log1pl which is otherwise unaffected by this patch. Tested for x86. * sysdeps/i386/fpu/i386-math-asm.h (DEFINE_LDBL_MIN): New macro. (FLT_CHECK_FORCE_UFLOW): Likewise. (DBL_CHECK_FORCE_UFLOW): Likewise. (FLT_CHECK_FORCE_UFLOW_NARROW): Likewise. (DBL_CHECK_FORCE_UFLOW_NARROW): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNAN): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. (FLT_CHECK_FORCE_UFLOW_NONNEG): Likewise. (DBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNEG): Likewise. * sysdeps/i386/fpu/e_asin.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_asin): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_asinf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_asinf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/e_atan2.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atan2): Use DBL_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atan2f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atan2f): Use FLT_CHECK_FORCE_UFLOW_NARROW. * sysdeps/i386/fpu/e_atanh.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__ieee754_atanh): Use DBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_atanhf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__ieee754_atanhf): Use FLT_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/e_exp2l.S: Include <i386-math-asm.h>. (ldbl_min): Replace with use of DEFINE_LDBL_MIN. (__ieee754_exp2l): Use LDBL_CHECK_FORCE_UFLOW_NONNEG_NAN. * sysdeps/i386/fpu/e_expl.S: Include <i386-math-asm.h>. [!USE_AS_EXPM1L] (cmin): Replace with use of DEFINE_LDBL_MIN. (IEEE754_EXPL): Use LDBL_CHECK_FORCE_UFLOW_NONNEG. * sysdeps/i386/fpu/s_atan.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__atan): Use DBL_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_atanf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__atanf): Use FLT_CHECK_FORCE_UFLOW. * sysdeps/i386/fpu/s_expm1.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (__expm1): Use DBL_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_expm1f.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (__expm1f): Use FLT_CHECK_FORCE_UFLOW. Move underflow check after main computation. * sysdeps/i386/fpu/s_log1p.S: Include <i386-math-asm.h>. (dbl_min): Replace with use of DEFINE_DBL_MIN. (MO): New macro. (__log1p): Use MO. Use DBL_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pf.S: Include <i386-math-asm.h>. (flt_min): Replace with use of DEFINE_FLT_MIN. (MO): New macro. (__log1pf): Use MO. Use FLT_CHECK_FORCE_UFLOW_NONNAN. * sysdeps/i386/fpu/s_log1pl.S (MO): New macro. (__log1pl): Use MO.
2015-09-24 21:41:00 +00:00
/* Likewise, but the argument is nonnegative and not a NaN. */
#define FLT_CHECK_FORCE_UFLOW_NONNEG \
fcoms MO(flt_min); \
fnstsw; \
sahf; \
jnc 6424f; \
subl $4, %esp; \
cfi_adjust_cfa_offset (4); \
fld %st(0); \
fmul %st(0); \
fstps (%esp); \
addl $4, %esp; \
cfi_adjust_cfa_offset (-4); \
6424:
#define DBL_CHECK_FORCE_UFLOW_NONNEG \
fcoml MO(dbl_min); \
fnstsw; \
sahf; \
jnc 6453f; \
subl $8, %esp; \
cfi_adjust_cfa_offset (8); \
fld %st(0); \
fmul %st(0); \
fstpl (%esp); \
addl $8, %esp; \
cfi_adjust_cfa_offset (-8); \
6453:
#define LDBL_CHECK_FORCE_UFLOW_NONNEG \
fldt MO(ldbl_min); \
fld %st(1); \
fcompp; \
fnstsw; \
sahf; \
jnc 6464f; \
fld %st(0); \
fmul %st(0); \
fstp %st(0); \
6464:
#endif /* i386-math-asm.h. */