glibc/sysdeps/i386/fpu/s_cbrtf.S
Paul Eggert 5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00

179 lines
4.3 KiB
ArmAsm

/* Compute cubic root of float value.
Copyright (C) 1997-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Dirk Alboth <dirka@uni-paderborn.de> and
Ulrich Drepper <drepper@cygnus.com>, 1997.
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/>. */
#include <machine/asm.h>
#include <libm-alias-float.h>
.section .rodata
.align ALIGNARG(4)
.type f3,@object
f3: .double 0.191502161678719066
ASM_SIZE_DIRECTIVE(f3)
.type f2,@object
f2: .double 0.697570460207922770
ASM_SIZE_DIRECTIVE(f2)
.type f1,@object
f1: .double 0.492659620528969547
ASM_SIZE_DIRECTIVE(f1)
#define CBRT2 1.2599210498948731648
#define ONE_CBRT2 0.793700525984099737355196796584
#define SQR_CBRT2 1.5874010519681994748
#define ONE_SQR_CBRT2 0.629960524947436582364439673883
.type factor,@object
.align ALIGNARG(4)
factor: .double ONE_SQR_CBRT2
.double ONE_CBRT2
.double 1.0
.double CBRT2
.double SQR_CBRT2
ASM_SIZE_DIRECTIVE(factor)
.type two25,@object
two25: .byte 0, 0, 0, 0x4c
ASM_SIZE_DIRECTIVE(two25)
#ifdef PIC
#define MO(op) op##@GOTOFF(%ebx)
#define MOX(op,x) op##@GOTOFF(%ebx,x,1)
#else
#define MO(op) op
#define MOX(op,x) op(x)
#endif
.text
ENTRY(__cbrtf)
movl 4(%esp), %eax
xorl %ecx, %ecx
movl %eax, %edx
andl $0x7fffffff, %eax
jz 1f
cmpl $0x7f800000, %eax
jae 1f
#ifdef PIC
pushl %ebx
cfi_adjust_cfa_offset (4)
cfi_rel_offset (ebx, 0)
LOAD_PIC_REG (bx)
#endif
cmpl $0x00800000, %eax
jae 2f
#ifdef PIC
flds 8(%esp)
#else
flds 4(%esp)
#endif
fmuls MO(two25)
movl $-25, %ecx
#ifdef PIC
fstps 8(%esp)
movl 8(%esp), %eax
#else
fstps 4(%esp)
movl 4(%esp), %eax
#endif
movl %eax, %edx
andl $0x7fffffff, %eax
2: shrl $23, %eax
andl $0x807fffff, %edx
subl $126, %eax
orl $0x3f000000, %edx
addl %eax, %ecx
#ifdef PIC
movl %edx, 8(%esp)
flds 8(%esp) /* xm */
#else
movl %edx, 4(%esp)
flds 4(%esp) /* xm */
#endif
fabs
/* The following code has two tracks:
a) compute the normalized cbrt value
b) compute xe/3 and xe%3
The right track computes the value for b) and this is done
in an optimized way by avoiding division.
But why two tracks at all? Very easy: efficiency. Some FP
instruction can overlap with a certain amount of integer (and
FP) instructions. So we get (except for the imull) all
instructions for free. */
fld %st(0) /* xm : xm */
fmull MO(f3) /* f3*xm : xm */
movl $1431655766, %eax
fsubrl MO(f2) /* f2-f3*xm : xm */
imull %ecx
fmul %st(1) /* (f2-f3*xm)*xm : xm */
movl %ecx, %eax
faddl MO(f1) /* u:=f1+(f2-f3*xm)*xm : xm */
sarl $31, %eax
fld %st /* u : u : xm */
subl %eax, %edx
fmul %st(1) /* u*u : u : xm */
fld %st(2) /* xm : u*u : u : xm */
fadd %st /* 2*xm : u*u : u : xm */
fxch %st(1) /* u*u : 2*xm : u : xm */
fmul %st(2) /* t2:=u*u*u : 2*xm : u : xm */
movl %edx, %eax
fadd %st, %st(1) /* t2 : t2+2*xm : u : xm */
leal (%edx,%edx,2),%edx
fadd %st(0) /* 2*t2 : t2+2*xm : u : xm */
subl %edx, %ecx
faddp %st, %st(3) /* t2+2*xm : u : 2*t2+xm */
shll $3, %ecx
fmulp /* u*(t2+2*xm) : 2*t2+xm */
fdivp %st, %st(1) /* u*(t2+2*xm)/(2*t2+xm) */
fmull MOX(16+factor,%ecx) /* u*(t2+2*xm)/(2*t2+xm)*FACT */
pushl %eax
cfi_adjust_cfa_offset (4)
fildl (%esp) /* xe/3 : u*(t2+2*xm)/(2*t2+xm)*FACT */
fxch /* u*(t2+2*xm)/(2*t2+xm)*FACT : xe/3 */
fscale /* u*(t2+2*xm)/(2*t2+xm)*FACT*2^xe/3 */
popl %edx
cfi_adjust_cfa_offset (-4)
#ifdef PIC
movl 8(%esp), %eax
popl %ebx
cfi_adjust_cfa_offset (-4)
cfi_restore (ebx)
#else
movl 4(%esp), %eax
#endif
testl %eax, %eax
fstp %st(1)
jns 4f
fchs
4: ret
/* Return the argument. */
1: flds 4(%esp)
ret
END(__cbrtf)
libm_alias_float (__cbrt, cbrt)