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/* Helper macros for x86 libm functions.
Copyright (C) 2015-2020 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
<https://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);
/* 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;
#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;
/* 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);
/* 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);
/* 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:
#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:
/* 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. */
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