1998-05-06 12:51  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/i386/fpu/bits/mathinline.h (pow): Use long long int for
	test for integer.

	* sysdeps/libm-i387/e_pow.S: Correctly shift double word.
	* sysdeps/libm-i387/e_powl.S: Likewise.

1998-03-31  Wolfram Gloger  <wmglo@dent.med.uni-muenchen.de>

	* malloc/malloc.c (chunk2mem_check, top_check): New functions.
	(malloc_check, free_check, realloc_check, memalign_check): Use
	them to improve overrun checking.  Overruns of a single byte and
	corruption of the top chunk are now detected much more reliably.

1998-05-06  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* math/libm-test.c (pow_test): Add test for special value from PR
	libc/590.
This commit is contained in:
Ulrich Drepper 1998-05-06 12:54:05 +00:00
parent 67c2095b54
commit b22fc5f565
10 changed files with 205 additions and 126 deletions

View file

@ -1,3 +1,23 @@
1998-05-06 12:51 Ulrich Drepper <drepper@cygnus.com>
* sysdeps/i386/fpu/bits/mathinline.h (pow): Use long long int for
test for integer.
* sysdeps/libm-i387/e_pow.S: Correctly shift double word.
* sysdeps/libm-i387/e_powl.S: Likewise.
1998-03-31 Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
* malloc/malloc.c (chunk2mem_check, top_check): New functions.
(malloc_check, free_check, realloc_check, memalign_check): Use
them to improve overrun checking. Overruns of a single byte and
corruption of the top chunk are now detected much more reliably.
1998-05-06 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* math/libm-test.c (pow_test): Add test for special value from PR
libc/590.
1998-05-06 Ulrich Drepper <drepper@cygnus.com>
* sysdeps/unix/sysv/linux/bits/errno.h: Undefine EILSEQ before

View file

@ -754,4 +754,36 @@ have-thread-library = yes
rpath-link := $(rpath-link):$(common-objpfx)linuxthreads
endif
ifndef avoid-generated
-include $(common-objpfx)sysd-dirs
define \n
endef
sysdep-subdirs := $(subst $(\n), ,$(sysdep-subdirs))
endif
# These are the subdirectories containing the library source.
subdirs = csu assert ctype db2 locale intl catgets math setjmp signal stdlib \
stdio-common $(stdio) malloc string wcsmbs time dirent grp pwd \
posix io termios resource misc socket sysvipc gmon gnulib iconv \
iconvdata wctype manual shadow md5-crypt po argp $(add-ons) nss \
localedata timezone rt $(sysdep-subdirs) $(binfmt-subdir)
# The mach and hurd subdirectories have many generated header files which
# much of the rest of the library depends on, so it is best to build them
# first (and mach before hurd, at that). The before-compile additions in
# sysdeps/{mach,hurd}/Makefile should make it reliably work for these files
# not to exist when making in other directories, but it will be slower that
# way with more somewhat expensive `make' invocations.
subdirs := $(filter mach,$(subdirs)) $(filter hurd,$(subdirs)) \
$(filter-out mach hurd,$(subdirs))
all-Subdirs-files = $(wildcard $(addsuffix /Subdirs, $(config-sysdirs)))
$(common-objpfx)sysd-dirs: $(common-objpfx)config.make $(all-Subdirs-files)
(echo define sysdep-subdirs; \
sed 's/#.*$$//' $(all-Subdirs-files) /dev/null; \
echo endef) > $@-tmp
mv -f $@-tmp $@
endif # Makeconfig not yet included

View file

@ -50,32 +50,6 @@ endif
configure: configure.in aclocal.m4; $(autoconf-it)
%/configure: %/configure.in aclocal.m4; $(autoconf-it)
ifndef avoid-generated
-include $(objpfx)sysd-dirs
define \n
endef
sysdep-subdirs := $(subst $(\n), ,$(sysdep-subdirs))
endif
# These are the subdirectories containing the library source.
subdirs = csu assert ctype db2 locale intl catgets math setjmp signal stdlib \
stdio-common $(stdio) malloc string wcsmbs time dirent grp pwd \
posix io termios resource misc socket sysvipc gmon gnulib iconv \
iconvdata wctype manual shadow md5-crypt po argp $(add-ons) nss \
localedata timezone rt $(sysdep-subdirs) $(binfmt-subdir)
export subdirs := $(subdirs) # Benign, useless in GNU make before 3.63.
# The mach and hurd subdirectories have many generated header files which
# much of the rest of the library depends on, so it is best to build them
# first (and mach before hurd, at that). The before-compile additions in
# sysdeps/{mach,hurd}/Makefile should make it reliably work for these files
# not to exist when making in other directories, but it will be slower that
# way with more somewhat expensive `make' invocations.
subdirs := $(filter mach,$(subdirs)) $(filter hurd,$(subdirs)) \
$(filter-out mach hurd,$(subdirs))
# All initialization source files.
+subdir_inits := $(wildcard $(foreach dir,$(subdirs),$(dir)/init-$(dir).c))
# All subdirectories containing initialization source files.
@ -158,13 +132,6 @@ ifeq (yes,$(build-shared))
# Build the shared object from the PIC object library.
lib: $(common-objpfx)libc.so
endif
all-Subdirs-files = $(wildcard $(addsuffix /Subdirs, $(config-sysdirs)))
$(objpfx)sysd-dirs: $(+sysdir_pfx)config.make $(all-Subdirs-files)
(echo define sysdep-subdirs; \
sed 's/#.*$$//' $(all-Subdirs-files) /dev/null; \
echo endef) > $@-tmp
mv -f $@-tmp $@
all-Banner-files = $(wildcard $(addsuffix /Banner, $(subdirs)))
$(objpfx)version-info.h: $(+sysdir_pfx)config.make $(all-Banner-files)

View file

@ -369,22 +369,16 @@ ifndef libc.so-version
static-only-routines =
endif
elide-routines.oS = $(filter-out $(static-only-routines),\
$(routines) $(aux) $(sysdep_routines))
ifdef static-only-routines
elide-routines.oS += $(filter-out $(static-only-routines),\
$(routines) $(aux) $(sysdep_routines))
elide-routines.os += $(static-only-routines)
endif
ifdef shared-only-routines
# If we have versioned code we don't need the old versions in any of the
# static libraries.
define o-iterator-doit
elide-routines.$o := $(shared-only-routines)
endef
object-suffixes-left := $(filter-out .os,$(object-suffixes))
include $(o-iterator)
endif
elide-routines.o += $(shared-only-routines)
elide-routines.op += $(shared-only-routines)
elide-routines.og += $(shared-only-routines)
elide-routines.ob += $(shared-only-routines)
# Don't try to use -lc when making libc.so itself.
# Also omits crti.o and crtn.o, which we do not want
@ -497,14 +491,14 @@ CREATE_ARFLAGS := cru$(verbose)
# This makes all the object files in the parent library archive.
.PHONY: lib lib-noranlib
lib: lib-noranlib $(foreach l,$(libtypes),$(patsubst %,$(common-objpfx)$l,c))
lib: $(foreach l,$(libtypes),$(patsubst %,$(common-objpfx)$l,c))
lib-noranlib: libobjs
# For object-suffix $o, the list of objects with that suffix.
# Makefiles can define `elide-routines.so = foo' to leave foo.so out.
o-objects = $(patsubst %.o,%$o,$(filter-out $(patsubst %,$(objpfx)%.o,\
$(elide-routines$o)),\
$(objects)))
lib-noranlib: libobjs
others: $(addprefix $(objpfx),$(install-lib))
ifndef objects
@ -525,52 +519,33 @@ define o-iterator-doit
$(objpfx)stamp$o: $(o-objects); $$(do-stamp)
endef
define do-stamp
echo '$(patsubst $(common-objpfx)%,%,$^)' > $@T
mv -f $@T $@
echo '$(patsubst $(common-objpfx)%,%,$^)' > $@T
mv -f $@T $@
endef
ifdef static-only-routines
object-suffixes-left := $(object-suffixes-for-libc)
else
object-suffixes-left := $(object-suffixes)
endif
include $(o-iterator)
ifndef static-only-routines
subdir_lib: $(objpfx)stamp.oS
$(objpfx)stamp.oS:
$(make-target-directory)
rm -f $@; > $@
endif
endif
# Now define explicit rules to build the library archives; these depend
# on the stamp files built above. The rule always destroys and recreates
# the library from scratch; it's faster (!) that way.
# the library from scratch; it's faster that way.
define o-iterator-doit
$(common-objpfx)$(patsubst %,$(libtype$o),c): \
$(subdirs-stamp-o) $(common-objpfx)stamp$o; $$(do-makelib)
endef
define do-makelib
(set -e; cd $(common-objdir); \
$(AR) $(CREATE_ARFLAGS) $(@F)T \
`cat $(patsubst $(common-objpfx)%,%,$^)`; \
$(RANLIB) $(@F)T; \
mv -f $(@F)T $(@F))
cd $(common-objdir) && \
$(AR) $(CREATE_ARFLAGS) $(@F)T `cat $(patsubst $(common-objpfx)%,%,$^)`
$(RANLIB) $@T
mv -f $@T $@
endef
subdirs-stamps := $(foreach d,$(subdirs),$(common-objpfx)$d/stamp%)
subdirs-stamp-o = $(subst %,$o,$(subdirs-stamps))
ifndef subdir
subdirs-stamps := $(foreach d,$(subdirs),$(common-objpfx)$d/stamp%)
subdirs-stamp-o = $(subst %,$o,$(subdirs-stamps))
$(subdirs-stamps): subdir_lib;
$(subdirs-stamps): $(foreach o,$(object-suffixes-for-libc),$(objpfx)stamp$o) \
subdir_lib;
endif
# The elf directory needs to know subdirs-stamp-o; otherwise libc_pic.a
# is mangled. FIXME: It would be cleaner to move the final construction
# of ld.so to top level.
ifeq ($(subdir),elf)
subdirs-stamps := $(foreach d,$(subdirs),$(common-objpfx)$d/stamp%)
subdirs-stamp-o = $(subst %,$o,$(subdirs-stamps))
endif
object-suffixes-left = $(object-suffixes-for-libc)
include $(o-iterator)
@ -939,8 +914,10 @@ common-clean: common-mostlyclean
# looking for references to <stub-tag.h>. Then we grovel over each
# referenced source file to see what stub function it defines.
ifdef objpfx
.PHONY: stubs # The parent Makefile calls this target.
stubs: $(objpfx)stubs
endif
s = $(sysdep_dir)/generic
$(objpfx)stubs: $(+depfiles)
# Use /dev/null since `...` might expand to empty.

View file

@ -523,6 +523,14 @@ do { \
#define MAP_ANONYMOUS MAP_ANON
#endif
#ifndef MAP_NORESERVE
# ifdef MAP_AUTORESRV
# define MAP_NORESERVE MAP_AUTORESRV
# else
# define MAP_NORESERVE 0
# endif
#endif
#endif /* HAVE_MMAP */
/*
@ -1757,15 +1765,15 @@ __malloc_check_init()
static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
#define MMAP(size, prot) ((dev_zero_fd < 0) ? \
#define MMAP(size, prot, flags) ((dev_zero_fd < 0) ? \
(dev_zero_fd = open("/dev/zero", O_RDWR), \
mmap(0, (size), (prot), MAP_PRIVATE, dev_zero_fd, 0)) : \
mmap(0, (size), (prot), MAP_PRIVATE, dev_zero_fd, 0))
mmap(0, (size), (prot), (flags), dev_zero_fd, 0)) : \
mmap(0, (size), (prot), (flags), dev_zero_fd, 0))
#else
#define MMAP(size, prot) \
(mmap(0, (size), (prot), MAP_PRIVATE|MAP_ANONYMOUS, -1, 0))
#define MMAP(size, prot, flags) \
(mmap(0, (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0))
#endif
@ -1791,7 +1799,7 @@ mmap_chunk(size) size_t size;
*/
size = (size + SIZE_SZ + page_mask) & ~page_mask;
p = (mchunkptr)MMAP(size, PROT_READ|PROT_WRITE);
p = (mchunkptr)MMAP(size, PROT_READ|PROT_WRITE, MAP_PRIVATE);
if(p == (mchunkptr) MAP_FAILED) return 0;
n_mmaps++;
@ -1920,7 +1928,11 @@ new_heap(size) size_t size;
size = HEAP_MAX_SIZE;
size = (size + page_mask) & ~page_mask;
p1 = (char *)MMAP(HEAP_MAX_SIZE<<1, PROT_NONE);
/* A memory region aligned to a multiple of HEAP_MAX_SIZE is needed.
No swap space needs to be reserved for the following large
mapping (on Linux, this is the case for all non-writable mappings
anyway). */
p1 = (char *)MMAP(HEAP_MAX_SIZE<<1, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE);
if(p1 == MAP_FAILED)
return 0;
p2 = (char *)(((unsigned long)p1 + HEAP_MAX_SIZE) & ~(HEAP_MAX_SIZE-1));
@ -2014,6 +2026,7 @@ arena_get2(a_tsd, size) arena *a_tsd; size_t size;
}
/* Check the global, circularly linked list for available arenas. */
repeat:
do {
if(!mutex_trylock(&a->mutex)) {
THREAD_STAT(++(a->stat_lock_loop));
@ -2023,6 +2036,16 @@ arena_get2(a_tsd, size) arena *a_tsd; size_t size;
a = a->next;
} while(a != a_tsd);
/* If not even the list_lock can be obtained, try again. This can
happen during `atfork', or for example on systems where thread
creation makes it temporarily impossible to obtain _any_
locks. */
if(mutex_trylock(&list_lock)) {
a = a_tsd;
goto repeat;
}
(void)mutex_unlock(&list_lock);
/* Nothing immediately available, so generate a new arena. */
h = new_heap(size + (sizeof(*h) + sizeof(*a) + MALLOC_ALIGNMENT));
if(!h)
@ -3780,9 +3803,6 @@ malloc_update_mallinfo(ar_ptr, mi) arena *ar_ptr; struct mallinfo *mi;
#endif
INTERNAL_SIZE_T avail;
/* Initialize the memory. */
memset (mi, '\0', sizeof (struct mallinfo));
(void)mutex_lock(&ar_ptr->mutex);
avail = chunksize(top(ar_ptr));
navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0;
@ -3806,6 +3826,7 @@ malloc_update_mallinfo(ar_ptr, mi) arena *ar_ptr; struct mallinfo *mi;
mi->arena = ar_ptr->size;
mi->ordblks = navail;
mi->smblks = mi->usmblks = mi->fsmblks = 0; /* clear unused fields */
mi->uordblks = ar_ptr->size - avail;
mi->fordblks = avail;
mi->hblks = n_mmaps;
@ -4136,13 +4157,39 @@ mALLOC_SET_STATe(msptr) Void_t* msptr;
/* A simple, standard set of debugging hooks. Overhead is `only' one
byte per chunk; still this will catch most cases of double frees or
overruns. */
overruns. The goal here is to avoid obscure crashes due to invalid
usage, unlike in the MALLOC_DEBUG code. */
#define MAGICBYTE(p) ( ( ((size_t)p >> 3) ^ ((size_t)p >> 11)) & 0xFF )
/* Instrument a chunk with overrun detector byte(s) and convert it
into a user pointer with requested size sz. */
static Void_t*
#if __STD_C
chunk2mem_check(mchunkptr p, size_t sz)
#else
chunk2mem_check(p, sz) mchunkptr p; size_t sz;
#endif
{
unsigned char* m_ptr = (unsigned char*)chunk2mem(p);
size_t i;
for(i = chunksize(p) - (chunk_is_mmapped(p) ? 2*SIZE_SZ+1 : SIZE_SZ+1);
i > sz;
i -= 0xFF) {
if(i-sz < 0x100) {
m_ptr[i] = (unsigned char)(i-sz);
break;
}
m_ptr[i] = 0xFF;
}
m_ptr[sz] = MAGICBYTE(p);
return (Void_t*)m_ptr;
}
/* Convert a pointer to be free()d or realloc()ed to a valid chunk
pointer. If the provided pointer is not valid, return NULL. The
goal here is to avoid crashes, unlike in the MALLOC_DEBUG code. */
pointer. If the provided pointer is not valid, return NULL. */
static mchunkptr
internal_function
@ -4153,7 +4200,8 @@ mem2chunk_check(mem) Void_t* mem;
#endif
{
mchunkptr p;
INTERNAL_SIZE_T sz;
INTERNAL_SIZE_T sz, c;
unsigned char magic;
p = mem2chunk(mem);
if(!aligned_OK(p)) return NULL;
@ -4166,9 +4214,11 @@ mem2chunk_check(mem) Void_t* mem;
(long)prev_chunk(p)<(long)sbrk_base ||
next_chunk(prev_chunk(p))!=p) ))
return NULL;
if(*((unsigned char*)p + sz + (SIZE_SZ-1)) != MAGICBYTE(p))
return NULL;
*((unsigned char*)p + sz + (SIZE_SZ-1)) ^= 0xFF;
magic = MAGICBYTE(p);
for(sz += SIZE_SZ-1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
}
((unsigned char*)p)[sz] ^= 0xFF;
} else {
unsigned long offset, page_mask = malloc_getpagesize-1;
@ -4184,13 +4234,53 @@ mem2chunk_check(mem) Void_t* mem;
( (((unsigned long)p - p->prev_size) & page_mask) != 0 ) ||
( (sz = chunksize(p)), ((p->prev_size + sz) & page_mask) != 0 ) )
return NULL;
if(*((unsigned char*)p + sz - 1) != MAGICBYTE(p))
return NULL;
*((unsigned char*)p + sz - 1) ^= 0xFF;
magic = MAGICBYTE(p);
for(sz -= 1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
}
((unsigned char*)p)[sz] ^= 0xFF;
}
return p;
}
/* Check for corruption of the top chunk, and try to recover if
necessary. */
static int
top_check()
{
mchunkptr t = top(&main_arena);
char* brk, * new_brk;
INTERNAL_SIZE_T front_misalign, sbrk_size;
unsigned long pagesz = malloc_getpagesize;
if((char*)t + chunksize(t) == sbrk_base + sbrked_mem ||
t == initial_top(&main_arena)) return 0;
switch(check_action) {
case 1:
fprintf(stderr, "malloc: top chunk is corrupt\n");
break;
case 2:
abort();
}
/* Try to set up a new top chunk. */
brk = MORECORE(0);
front_misalign = (unsigned long)chunk2mem(brk) & MALLOC_ALIGN_MASK;
if (front_misalign > 0)
front_misalign = MALLOC_ALIGNMENT - front_misalign;
sbrk_size = front_misalign + top_pad + MINSIZE;
sbrk_size += pagesz - ((unsigned long)(brk + sbrk_size) & (pagesz - 1));
new_brk = (char*)(MORECORE (sbrk_size));
if (new_brk == (char*)(MORECORE_FAILURE)) return -1;
sbrked_mem = (new_brk - sbrk_base) + sbrk_size;
top(&main_arena) = (mchunkptr)(brk + front_misalign);
set_head(top(&main_arena), (sbrk_size - front_misalign) | PREV_INUSE);
return 0;
}
static Void_t*
#if __STD_C
malloc_check(size_t sz, const Void_t *caller)
@ -4202,16 +4292,10 @@ malloc_check(sz, caller) size_t sz; const Void_t *caller;
INTERNAL_SIZE_T nb = request2size(sz + 1);
(void)mutex_lock(&main_arena.mutex);
victim = chunk_alloc(&main_arena, nb);
victim = (top_check() >= 0) ? chunk_alloc(&main_arena, nb) : NULL;
(void)mutex_unlock(&main_arena.mutex);
if(!victim) return NULL;
nb = chunksize(victim);
if(chunk_is_mmapped(victim))
--nb;
else
nb += SIZE_SZ - 1;
*((unsigned char*)victim + nb) = MAGICBYTE(victim);
return chunk2mem(victim);
return chunk2mem_check(victim, sz);
}
static void
@ -4290,7 +4374,7 @@ realloc_check(oldmem, bytes, caller)
if(oldsize - SIZE_SZ >= nb) newp = oldp; /* do nothing */
else {
/* Must alloc, copy, free. */
newp = chunk_alloc(&main_arena, nb);
newp = (top_check() >= 0) ? chunk_alloc(&main_arena, nb) : NULL;
if (newp) {
MALLOC_COPY(chunk2mem(newp), oldmem, oldsize - 2*SIZE_SZ);
munmap_chunk(oldp);
@ -4301,7 +4385,8 @@ realloc_check(oldmem, bytes, caller)
#endif
} else {
#endif /* HAVE_MMAP */
newp = chunk_realloc(&main_arena, oldp, oldsize, nb);
newp = (top_check() >= 0) ?
chunk_realloc(&main_arena, oldp, oldsize, nb) : NULL;
#if 0 /* Erase freed memory. */
nb = chunksize(newp);
if(oldp<newp || oldp>=chunk_at_offset(newp, nb)) {
@ -4317,13 +4402,7 @@ realloc_check(oldmem, bytes, caller)
(void)mutex_unlock(&main_arena.mutex);
if(!newp) return NULL;
nb = chunksize(newp);
if(chunk_is_mmapped(newp))
--nb;
else
nb += SIZE_SZ - 1;
*((unsigned char*)newp + nb) = MAGICBYTE(newp);
return chunk2mem(newp);
return chunk2mem_check(newp, bytes);
}
static Void_t*
@ -4342,16 +4421,10 @@ memalign_check(alignment, bytes, caller)
nb = request2size(bytes+1);
(void)mutex_lock(&main_arena.mutex);
p = chunk_align(&main_arena, nb, alignment);
p = (top_check() >= 0) ? chunk_align(&main_arena, nb, alignment) : NULL;
(void)mutex_unlock(&main_arena.mutex);
if(!p) return NULL;
nb = chunksize(p);
if(chunk_is_mmapped(p))
--nb;
else
nb += SIZE_SZ - 1;
*((unsigned char*)p + nb) = MAGICBYTE(p);
return chunk2mem(p);
return chunk2mem_check(p, bytes);
}
/* The following hooks are used when the global initialization in

View file

@ -198,7 +198,7 @@ subdir_%: ;
# None of these should be `subdir_TARGET'; those targets are transformed
# by the implicit rule above into `TARGET' deps.
glibc-targets := lib objects objs others tests lint.out \
echo-headers echo-distinfo stubs
echo-headers echo-distinfo
.PHONY: $(glibc-targets)
$(glibc-targets):
@ -206,7 +206,10 @@ $(glibc-targets):
# updating the library archives are happy with us, and never think we have
# changed the library.
lib: $(foreach o,$(object-suffixes-for-libc),$(objpfx)stamp$o)
ifdef objpfx
.PHONY: stubs
stubs: $(objpfx)stubs
endif
$(objpfx)stubs ../po/manual.pot $(objpfx)stamp%:
$(make-target-directory)
cp /dev/null $@

View file

@ -2203,6 +2203,11 @@ pow_test (void)
check_eps ("pow (0.7, 1.2) == 0.65180...", FUNC(pow) (0.7, 1.2),
0.65180494056638638188L, CHOOSE(4e-17L, 0, 0));
#ifdef TEST_DOUBLE
check ("pow (-7.49321e+133, -9.80818e+16) == 0",
FUNC(pow) (-7.49321e+133, -9.80818e+16), 0);
#endif
}

View file

@ -376,7 +376,7 @@ __inline_mathcode2 (fmod, __x, __y, \
__inline_mathcode2 (pow, __x, __y, \
register long double __value; \
register long double __exponent; \
long int __p = (long int) __y; \
long long int __p = (long long int) __y; \
if (__x == 0.0 && __y > 0.0) \
return 0.0; \
if (__y == (double) __p) \

View file

@ -1,5 +1,5 @@
/* ix87 specific implementation of pow function.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
@ -125,6 +125,7 @@ ENTRY(__ieee754_pow)
fmul %st(1) // x : ST*x
fxch
5: fmul %st(0), %st // x*x : ST*x
shrl $1, %edx
movl %eax, %ecx
orl %edx, %ecx
jnz 6b

View file

@ -1,5 +1,5 @@
/* ix87 specific implementation of pow function.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
@ -125,6 +125,7 @@ ENTRY(__ieee754_powl)
fmul %st(1) // x : ST*x
fxch
5: fmul %st(0), %st // x*x : ST*x
shrl $1, %edx
movl %eax, %ecx
orl %edx, %ecx
jnz 6b