Hi Richard,
None, is there any? All the one I could find in the big switch
selecting tm_files and tmake_files in gcc/config.gcc are including
arm/elf.h. I tried to build for arm-wince-pe but got: "Configuration
arm-wince-pe not supported". However note that to guarantee correct
results the only requirement is to support global symbol overriding
weak symbol correctly and I see .weak usage in many other libgcc
backend (eg. i386). The "take the first definition resolving an
undefined reference and ignore the one in following object of a static
library" is only to benefit from the size optimization.
Best regards,
Thomas
On Fri, 7 Dec 2018 at 14:14, Richard Earnshaw (lists)
<richard.earns...@arm.com> wrote:
>
> On 19/11/2018 09:57, Thomas Preudhomme wrote:
> > Softfloat single precision and double precision floating-point
> > multiplication routines in libgcc share some code with the
> > floating-point division of their corresponding precision. As the code
> > is structured now, this leads to *all* division code being pulled in an
> > executable in softfloat mode even if only multiplication is
> > performed.
> >
> > This patch create some new LIB1ASMFUNCS macros to also build files with
> > just the multiplication and shared code as weak symbols. By putting
> > these earlier in the static library, they can then be picked up when
> > only multiplication is used and they are overriden by the global
> > definition in the existing file containing both multiplication and
> > division code when division is needed.
> >
> > The patch also removes changes made to the FUNC_START and ARM_FUNC_START
> > macros in r218124 since the intent was to put multiplication and
> > division code into their own section in a later patch to achieve the
> > same size optimization. That approach relied on specific section layout
> > to ensure multiplication and division were not too far from the shared
> > bit of code in order to the branches to be within range. Due to lack of
> > guarantee regarding section layout, in particular with all the
> > possibility of linker scripts, this approach was chosen instead. This
> > patch keeps the two testcases that were posted by Tony Wang (an Arm
> > employee at the time) on the mailing list to implement this approach
> > and adds a new one, hence the attribution.
> >
> > ChangeLog entries are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2018-11-14 Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * config/arm/elf.h: Update comment about condition that need to
> > match with libgcc/config/arm/lib1funcs.S to also include
> > libgcc/config/arm/t-arm.
> > * doc/sourcebuild.texi (output-exists, output-exists-not): Rename
> > subsubsection these directives are in to "Check for output files".
> > Move scan-symbol to that section and add to it new scan-symbol-not
> > directive.
> >
> > *** gcc/testsuite/ChangeLog ***
> >
> > 2018-11-16 Tony Wang <tony.w...@arm.com>
> > Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * lib/lto.exp (lto-execute): Define output_file and testname_with_flags
> > to same value as execname.
> > (scan-symbol): Move and rename to ...
> > * lib/gcc-dg.exp (scan-symbol-common): This. Adapt into a
> > helper function returning true or false if a symbol is present.
> > (scan-symbol): New procedure.
> > (scan-symbol-not): Likewise.
> > * gcc.target/arm/size-optimization-ieee-1.c: New testcase.
> > * gcc.target/arm/size-optimization-ieee-2.c: Likewise.
> > * gcc.target/arm/size-optimization-ieee-3.c: Likewise.
> >
> > *** libgcc/ChangeLog ***
> >
> > 2018-11-16 Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * /config/arm/lib1funcs.S (FUNC_START): Remove unused sp_section
> > parameter and corresponding code.
> > (ARM_FUNC_START): Likewise in both definitions.
> > Also update footer comment about condition that need to match with
> > gcc/config/arm/elf.h to also include libgcc/config/arm/t-arm.
> > * config/arm/ieee754-df.S (muldf3): Also build it if L_arm_muldf3 is
> > defined. Weakly define it in this case.
> > * config/arm/ieee754-sf.S (mulsf3): Likewise with L_arm_mulsf3.
> > * config/arm/t-elf (LIB1ASMFUNCS): Build _arm_muldf3.o and
> > _arm_mulsf3.o before muldiv versions if targeting Thumb-1 only. Add
> > comment to keep condition in sync with the one in
> > libgcc/config/arm/lib1funcs.S and gcc/config/arm/elf.h.
> >
> > Testing: Bootstrapped on arm-linux-gnueabihf (Arm & Thumb-2) and
> > testsuite shows no
> > regression. Also built an arm-none-eabi cross compiler targeting
> > soft-float which also shows no regression. In particular newly added
> > tests and gcc.dg/lto/20081212-1 test pass.
>
> Which non-elf targets have you tested?
>
> R.
>
> >
> > Is this ok for stage3?
> >
> > Best regards,
> >
> > Thomas
> >
> >
> > Optimize-size-fpmul_without_div.patch
> >
> > From 8740697791f99b7175e188f049663883c39e51b0 Mon Sep 17 00:00:00 2001
> > From: Thomas Preud'homme <thomas.preudho...@linaro.org>
> > Date: Fri, 26 Oct 2018 16:21:09 +0100
> > Subject: [PATCH] [PATCH, libgcc/ARM] Optimize executable size when using
> > softfloat fmul/dmul
> >
> > Softfloat single precision and double precision floating-point
> > multiplication routines in libgcc share some code with the
> > floating-point division of their corresponding precision. As the code
> > is structured now, this leads to *all* division code being pulled in an
> > executable in softfloat mode even if only multiplication is
> > performed.
> >
> > This patch create some new LIB1ASMFUNCS macros to also build files with
> > just the multiplication and shared code as weak symbols. By putting
> > these earlier in the static library, they can then be picked up when
> > only multiplication is used and they are overriden by the global
> > definition in the existing file containing both multiplication and
> > division code when division is needed.
> >
> > The patch also removes changes made to the FUNC_START and ARM_FUNC_START
> > macros in r218124 since the intent was to put multiplication and
> > division code into their own section in a later patch to achieve the
> > same size optimization. That approach relied on specific section layout
> > to ensure multiplication and division were not too far from the shared
> > bit of code in order to the branches to be within range. Due to lack of
> > guarantee regarding section layout, in particular with all the
> > possibility of linker scripts, this approach was chosen instead. This
> > patch keeps the two testcases that were posted by Tony Wang (an Arm
> > employee at the time) on the mailing list to implement this approach
> > and adds a new one, hence the attribution.
> >
> > ChangeLog entries are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2018-11-14 Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * config/arm/elf.h: Update comment about condition that need to
> > match with libgcc/config/arm/lib1funcs.S to also include
> > libgcc/config/arm/t-arm.
> > * doc/sourcebuild.texi (output-exists, output-exists-not): Rename
> > subsubsection these directives are in to "Check for output files".
> > Move scan-symbol to that section and add to it new scan-symbol-not
> > directive.
> >
> > *** gcc/testsuite/ChangeLog ***
> >
> > 2018-11-16 Tony Wang <tony.w...@arm.com>
> > Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * lib/lto.exp (lto-execute): Define output_file and
> > testname_with_flags
> > to same value as execname.
> > (scan-symbol): Move and rename to ...
> > * lib/gcc-dg.exp (scan-symbol-common): This. Adapt into a
> > helper function returning true or false if a symbol is present.
> > (scan-symbol): New procedure.
> > (scan-symbol-not): Likewise.
> > * gcc.target/arm/size-optimization-ieee-1.c: New testcase.
> > * gcc.target/arm/size-optimization-ieee-2.c: Likewise.
> > * gcc.target/arm/size-optimization-ieee-3.c: Likewise.
> >
> > *** libgcc/ChangeLog ***
> >
> > 2018-11-16 Thomas Preud'homme <thomas.preudho...@linaro.org>
> >
> > * /config/arm/lib1funcs.S (FUNC_START): Remove unused sp_section
> > parameter and corresponding code.
> > (ARM_FUNC_START): Likewise in both definitions.
> > Also update footer comment about condition that need to match with
> > gcc/config/arm/elf.h to also include libgcc/config/arm/t-arm.
> > * config/arm/ieee754-df.S (muldf3): Also build it if L_arm_muldf3 is
> > defined. Weakly define it in this case.
> > * config/arm/ieee754-sf.S (mulsf3): Likewise with L_arm_mulsf3.
> > * config/arm/t-elf (LIB1ASMFUNCS): Build _arm_muldf3.o and
> > _arm_mulsf3.o before muldiv versions if targeting Thumb-1 only. Add
> > comment to keep condition in sync with the one in
> > libgcc/config/arm/lib1funcs.S and gcc/config/arm/elf.h.
> >
> > Testing: Bootstrapped on arm-linux-gnueabihf and testsuite shows no
> > regression. Also built an arm-none-eabi cross compiler targeting
> > soft-float which also shows no regression. In particular newly added
> > tests and gcc.dg/lto/20081212-1 test pass.
> >
> > Is this ok for stage3?
> >
> > Best regards,
> >
> > Thomas
> > ---
> > gcc/config/arm/elf.h | 2 +-
> > gcc/doc/sourcebuild.texi | 9 +--
> > .../gcc.target/arm/size-optimization-ieee-1.c | 33 ++++++++
> > .../gcc.target/arm/size-optimization-ieee-2.c | 31 ++++++++
> > .../gcc.target/arm/size-optimization-ieee-3.c | 33 ++++++++
> > gcc/testsuite/lib/gcc-dg.exp | 76 +++++++++++++++++++
> > gcc/testsuite/lib/lto.exp | 63 +++------------
> > libgcc/config/arm/ieee754-df.S | 17 ++++-
> > libgcc/config/arm/ieee754-sf.S | 16 +++-
> > libgcc/config/arm/lib1funcs.S | 19 ++---
> > libgcc/config/arm/t-elf | 16 ++++
> > 11 files changed, 243 insertions(+), 72 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.target/arm/size-optimization-ieee-1.c
> > create mode 100644 gcc/testsuite/gcc.target/arm/size-optimization-ieee-2.c
> > create mode 100644 gcc/testsuite/gcc.target/arm/size-optimization-ieee-3.c
> >
> > diff --git a/gcc/config/arm/elf.h b/gcc/config/arm/elf.h
> > index ad3651ba841..1e00e99afc6 100644
> > --- a/gcc/config/arm/elf.h
> > +++ b/gcc/config/arm/elf.h
> > @@ -137,7 +137,7 @@
> >
> > /* Horrible hack: We want to prevent some libgcc routines being included
> > for some multilibs. The condition should match the one in
> > - libgcc/config/arm/lib1funcs.S. */
> > + libgcc/config/arm/lib1funcs.S and libgcc/config/arm/t-elf. */
> > #if __ARM_ARCH_ISA_ARM || __ARM_ARCH_ISA_THUMB != 1
> > #undef L_fixdfsi
> > #undef L_fixunsdfsi
> > diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
> > index 89157079ffb..9bf59b81d87 100644
> > --- a/gcc/doc/sourcebuild.texi
> > +++ b/gcc/doc/sourcebuild.texi
> > @@ -2638,7 +2638,7 @@ Passes if @var{regex} does not match demangled text
> > in the dump file with
> > suffix @var{suffix}.
> > @end table
> >
> > -@subsubsection Verify that an output files exists or not
> > +@subsubsection Check for output files
> >
> > @table @code
> > @item output-exists [@{ target/xfail @var{selector} @}]
> > @@ -2646,13 +2646,12 @@ Passes if compiler output file exists.
> >
> > @item output-exists-not [@{ target/xfail @var{selector} @}]
> > Passes if compiler output file does not exist.
> > -@end table
> > -
> > -@subsubsection Check for LTO tests
> >
> > -@table @code
> > @item scan-symbol @var{regexp} [@{ target/xfail @var{selector} @}]
> > Passes if the pattern is present in the final executable.
> > +
> > +@item scan-symbol-not @var{regexp} [@{ target/xfail @var{selector} @}]
> > +Passes if the pattern is absent from the final executable.
> > @end table
> >
> > @subsubsection Checks for @command{gcov} tests
> > diff --git a/gcc/testsuite/gcc.target/arm/size-optimization-ieee-1.c
> > b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-1.c
> > new file mode 100644
> > index 00000000000..34090f20fec
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-1.c
> > @@ -0,0 +1,33 @@
> > +/* { dg-do link { target arm_soft_ok } } */
> > +/* { dg-options "-mfloat-abi=soft" } */
> > +
> > +int
> > +foo (void)
> > +{
> > + volatile float a;
> > + volatile float b;
> > + volatile float c = a * b;
> > + return 0;
> > +}
> > +
> > +int
> > +bar (void)
> > +{
> > + volatile double a;
> > + volatile double b;
> > + volatile double c = a * b;
> > + return 0;
> > +}
> > +
> > +int
> > +main (void)
> > +{
> > + foo ();
> > + bar ();
> > + return 0;
> > +}
> > +
> > +/* { dg-final { scan-symbol "__aeabi_fmul" } } */
> > +/* { dg-final { scan-symbol "__aeabi_dmul" } } */
> > +/* { dg-final { scan-symbol-not "__aeabi_fdiv" } } */
> > +/* { dg-final { scan-symbol-not "__aeabi_ddiv" } } */
> > diff --git a/gcc/testsuite/gcc.target/arm/size-optimization-ieee-2.c
> > b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-2.c
> > new file mode 100644
> > index 00000000000..75337894a9c
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-2.c
> > @@ -0,0 +1,31 @@
> > +/* { dg-do link { target arm_soft_ok } } */
> > +/* { dg-options "-mfloat-abi=soft" } */
> > +
> > +int
> > +foo (void)
> > +{
> > + volatile float a;
> > + volatile float b;
> > + volatile float c = a / b;
> > + return 0;
> > +}
> > +
> > +int
> > +bar (void)
> > +{
> > + volatile double a;
> > + volatile double b;
> > + volatile double c = a / b;
> > + return 0;
> > +}
> > +
> > +int
> > +main (void)
> > +{
> > + foo ();
> > + bar ();
> > + return 0;
> > +}
> > +
> > +/* { dg-final { scan-symbol "__aeabi_fdiv" } } */
> > +/* { dg-final { scan-symbol "__aeabi_ddiv" } } */
> > diff --git a/gcc/testsuite/gcc.target/arm/size-optimization-ieee-3.c
> > b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-3.c
> > new file mode 100644
> > index 00000000000..63c92b3bbb7
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/arm/size-optimization-ieee-3.c
> > @@ -0,0 +1,33 @@
> > +/* { dg-do link { target arm_soft_ok } } */
> > +/* { dg-options "-mfloat-abi=soft" } */
> > +
> > +int
> > +foo (void)
> > +{
> > + volatile float a;
> > + volatile float b;
> > + volatile float c = a * b + a / b;
> > + return 0;
> > +}
> > +
> > +int
> > +bar (void)
> > +{
> > + volatile double a;
> > + volatile double b;
> > + volatile double c = a * b + a / b;
> > + return 0;
> > +}
> > +
> > +int
> > +main (void)
> > +{
> > + foo ();
> > + bar ();
> > + return 0;
> > +}
> > +
> > +/* { dg-final { scan-symbol "__aeabi_fmul" } } */
> > +/* { dg-final { scan-symbol "__aeabi_dmul" } } */
> > +/* { dg-final { scan-symbol "__aeabi_fdiv" } } */
> > +/* { dg-final { scan-symbol "__aeabi_ddiv" } } */
> > diff --git a/gcc/testsuite/lib/gcc-dg.exp b/gcc/testsuite/lib/gcc-dg.exp
> > index c33a50c0b13..0472b63f94c 100644
> > --- a/gcc/testsuite/lib/gcc-dg.exp
> > +++ b/gcc/testsuite/lib/gcc-dg.exp
> > @@ -1236,5 +1236,81 @@ proc gdb-exists { args } {
> > return 0;
> > }
> >
> > +# Helper function for scan-symbol and scan-symbol-not. It scans a symbol in
> > +# the final executable and return 1 if present, otherwise fail.
> > +#
> > +# Argument 0 is the regexp to match.
> > +# Argument 1 handles expected failures and the like
> > +proc scan-symbol-common { scan_directive args } {
> > + global nm
> > + global base_dir
> > +
> > + # Access variable from gcc-dg-test-1 or lto-execute.
> > + upvar 3 output_file output_file
> > +
> > + if { [llength $args] >= 2 } {
> > + switch [dg-process-target [lindex $args 1]] {
> > + "S" { }
> > + "N" { return }
> > + "F" { setup_xfail "*-*-*" }
> > + "P" { }
> > + }
> > + }
> > +
> > + # Find nm like we find g++ in g++.exp.
> > + if ![info exists nm] {
> > + set nm [findfile $base_dir/../../../binutils/nm \
> > + $base_dir/../../../binutils/nm \
> > + [findfile $base_dir/../../nm $base_dir/../../nm \
> > + [findfile $base_dir/nm $base_dir/nm \
> > + [transform nm]]]]
> > + verbose -log "nm is $nm"
> > + }
> > +
> > + set output_file "[glob -nocomplain $output_file]"
> > + if { $output_file == "" } {
> > + fail "$scan_directive $args: output file does not exist"
> > + return
> > + }
> > +
> > + set fd [open "| $nm $output_file" r]
> > + set text [read $fd]
> > + close $fd
> > +
> > + if [regexp -- [lindex $args 0] $text] {
> > + return 1
> > + } else {
> > + return 0
> > + }
> > +}
> > +
> > +# Utility for scanning a symbol in the final executable, invoked via
> > dg-final.
> > +# Call pass if pattern is present, otherwise fail.
> > +#
> > +# Argument 0 is the regexp to match.
> > +# Argument 1 handles expected failures and the like
> > +proc scan-symbol { args } {
> > + set testcase [testname-for-summary]
> > + if { [scan-symbol-common "scan-symbol" $args]} {
> > + pass "$testcase scan-symbol $args"
> > + } else {
> > + fail "$testcase scan-symbol $args"
> > + }
> > +}
> > +
> > +# Utility for scanning a symbol in the final executable, invoked via
> > dg-final.
> > +# Call pass if pattern is absent, otherwise fail.
> > +#
> > +# Argument 0 is the regexp to match.
> > +# Argument 1 handles expected failures and the like
> > +proc scan-symbol-not { args } {
> > + set testcase [testname-for-summary]
> > + if { [scan-symbol-common "scan-symbol-not" $args]} {
> > + fail "$testcase scan-symbol-not $args"
> > + } else {
> > + pass "$testcase scan-symbol-not $args"
> > + }
> > +}
> > +
> > set additional_prunes ""
> > set dg_runtest_extra_prunes ""
> > diff --git a/gcc/testsuite/lib/lto.exp b/gcc/testsuite/lib/lto.exp
> > index 58a84aa1936..c2c35698827 100644
> > --- a/gcc/testsuite/lib/lto.exp
> > +++ b/gcc/testsuite/lib/lto.exp
> > @@ -712,6 +712,17 @@ proc lto-execute { src1 sid } {
> >
> > # There's a unique name for each executable we generate.
> > set execname "${execbase}-${count}1.exe"
> > +
> > + # The LTO tests don't use dg-test, so testname_with_flags and
> > + # output_file need to be defined explicitly for each file.
> > scan-symbol
> > + # directives rely on both of these to be defined to find the symbol to
> > + # scan and for the text to print in the PASS/FAIL since they can also
> > + # be called from dg-test. testname_with_flags is also used via
> > + # testname-for-summary when calling into generic function below to
> > + # clean temporary files.
> > + set output_file $execname
> > + set testname_with_flags $execname
> > +
> > incr count
> >
> > file_on_host delete $execname
> > @@ -774,11 +785,7 @@ proc lto-execute { src1 sid } {
> > }
> > }
> >
> > - # Clean up after -save-temps. The LTO tests don't use dg-test, so
> > - # testname-for-summary needs to be defined explicitly for each
> > - # file that needs to be removed.
> > - set testname_with_flags $execname
> > -
> > + # Clean up after -save-temps.
> > eval "cleanup-saved-temps"
> >
> > for {set i 0} {$i < $num_srcs} {incr i} {
> > @@ -801,52 +808,6 @@ proc lto-execute { src1 sid } {
> > }
> > }
> >
> > -# Utility for scanning a symbol in the final executable, invoked via
> > dg-final.
> > -# Call pass if pattern is present, otherwise fail.
> > -#
> > -# Argument 0 is the regexp to match.
> > -# Argument 1 handles expected failures and the like
> > -proc scan-symbol { args } {
> > - global nm
> > - global base_dir
> > - upvar 2 execname execname
> > -
> > - if { [llength $args] >= 2 } {
> > - switch [dg-process-target [lindex $args 1]] {
> > - "S" { }
> > - "N" { return }
> > - "F" { setup_xfail "*-*-*" }
> > - "P" { }
> > - }
> > - }
> > -
> > - # Find nm like we find g++ in g++.exp.
> > - if ![info exists nm] {
> > - set nm [findfile $base_dir/../../../binutils/nm \
> > - $base_dir/../../../binutils/nm \
> > - [findfile $base_dir/../../nm $base_dir/../../nm \
> > - [findfile $base_dir/nm $base_dir/nm \
> > - [transform nm]]]]
> > - verbose -log "nm is $nm"
> > - }
> > -
> > - set output_file "[glob -nocomplain $execname]"
> > - if { $output_file == "" } {
> > - fail "scan-symbol $args: dump file does not exist"
> > - return
> > - }
> > -
> > - set fd [open "| $nm $output_file" r]
> > - set text [read $fd]
> > - close $fd
> > -
> > - if [regexp -- [lindex $args 0] $text] {
> > - pass "scan-symbol $args"
> > - } else {
> > - fail "scan-symbol $args"
> > - }
> > -}
> > -
> > # Call pass if object readelf is ok, otherwise fail.
> > # example: /* { dg-final { object-readelf Tag_ABI_enum_size int} } */
> > proc object-readelf { args } {
> > diff --git a/libgcc/config/arm/ieee754-df.S b/libgcc/config/arm/ieee754-df.S
> > index 480e33da31f..9f2ae9ed698 100644
> > --- a/libgcc/config/arm/ieee754-df.S
> > +++ b/libgcc/config/arm/ieee754-df.S
> > @@ -617,7 +617,18 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf
> >
> > #endif /* L_addsubdf3 */
> >
> > -#ifdef L_arm_muldivdf3
> > +#if defined(L_arm_muldf3) || defined(L_arm_muldivdf3)
> > +
> > +@ Define multiplication as weak in _arm_muldf3.o so that it can be
> > overriden
> > +@ by the global definition in _arm_muldivdf3.o. This allows a program only
> > +@ using multiplication to take the weak definition which does not contain
> > the
> > +@ division code. Programs using only division or both division and
> > +@ multiplication will pull _arm_muldivdf3.o from which both the
> > multiplication
> > +@ and division are taken thanks to the override.
> > +#ifdef L_arm_muldf3
> > +WEAK muldf3
> > +WEAK aeabi_dmul
> > +#endif
> >
> > ARM_FUNC_START muldf3
> > ARM_FUNC_ALIAS aeabi_dmul muldf3
> > @@ -719,6 +730,7 @@ LSYM(Lml_1):
> > orr xh, xh, #0x00100000
> > mov lr, #0
> > subs r4, r4, #1
> > +
> > LSYM(Lml_u):
> > @ Overflow?
> > bgt LSYM(Lml_o)
> > @@ -870,6 +882,8 @@ LSYM(Lml_n):
> > FUNC_END aeabi_dmul
> > FUNC_END muldf3
> >
> > +#ifdef L_arm_muldivdf3
> > +
> > ARM_FUNC_START divdf3
> > ARM_FUNC_ALIAS aeabi_ddiv divdf3
> > CFI_START_FUNCTION
> > @@ -1067,6 +1081,7 @@ LSYM(Ldv_s):
> > FUNC_END divdf3
> >
> > #endif /* L_muldivdf3 */
> > +#endif /* L_arm_muldf3 || L_arm_muldivdf3 */
> >
> > #ifdef L_arm_cmpdf2
> >
> > diff --git a/libgcc/config/arm/ieee754-sf.S b/libgcc/config/arm/ieee754-sf.S
> > index 28e0d793281..0b4d1ab377d 100644
> > --- a/libgcc/config/arm/ieee754-sf.S
> > +++ b/libgcc/config/arm/ieee754-sf.S
> > @@ -428,7 +428,18 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf
> >
> > #endif /* L_addsubsf3 */
> >
> > -#ifdef L_arm_muldivsf3
> > +#if defined(L_arm_mulsf3) || defined(L_arm_muldivsf3)
> > +
> > +@ Define multiplication as weak in _arm_mulsf3.o so that it can be
> > overriden
> > +@ by the global definition in _arm_muldivsf3.o. This allows a program only
> > +@ using multiplication to take the weak definition which does not contain
> > the
> > +@ division code. Programs using only division or both division and
> > +@ multiplication will pull _arm_muldivsf3.o from which both the
> > multiplication
> > +@ and division are taken thanks to the override.
> > +#ifdef L_arm_mulsf3
> > +WEAK mulsf3
> > +WEAK aeabi_fmul
> > +#endif
> >
> > ARM_FUNC_START mulsf3
> > ARM_FUNC_ALIAS aeabi_fmul mulsf3
> > @@ -613,6 +624,8 @@ LSYM(Lml_n):
> > FUNC_END aeabi_fmul
> > FUNC_END mulsf3
> >
> > +#ifdef L_arm_muldivsf3
> > +
> > ARM_FUNC_START divsf3
> > ARM_FUNC_ALIAS aeabi_fdiv divsf3
> > CFI_START_FUNCTION
> > @@ -756,6 +769,7 @@ LSYM(Ldv_s):
> > FUNC_END divsf3
> >
> > #endif /* L_muldivsf3 */
> > +#endif /* L_arm_mulsf3 || L_arm_muldivsf3 */
> >
> > #ifdef L_arm_cmpsf2
> >
> > diff --git a/libgcc/config/arm/lib1funcs.S b/libgcc/config/arm/lib1funcs.S
> > index ff06d504a4c..193fb251fdb 100644
> > --- a/libgcc/config/arm/lib1funcs.S
> > +++ b/libgcc/config/arm/lib1funcs.S
> > @@ -359,12 +359,8 @@ SYM (\name):
> > #define THUMB_SYNTAX
> > #endif
> >
> > -.macro FUNC_START name sp_section=
> > - .ifc \sp_section, function_section
> > - .section .text.__\name,"ax",%progbits
> > - .else
> > +.macro FUNC_START name
> > .text
> > - .endif
> > .globl SYM (__\name)
> > TYPE (__\name)
> > .align 0
> > @@ -390,8 +386,8 @@ SYM (\name):
> > #if defined(__thumb2__)
> >
> > /* For Thumb-2 we build everything in thumb mode. */
> > -.macro ARM_FUNC_START name sp_section=
> > - FUNC_START \name \sp_section
> > +.macro ARM_FUNC_START name
> > + FUNC_START \name
> > .syntax unified
> > .endm
> > #define EQUIV .thumb_set
> > @@ -422,12 +418,8 @@ _L__\name:
> > #ifdef NOT_ISA_TARGET_32BIT
> > #define EQUIV .thumb_set
> > #else
> > -.macro ARM_FUNC_START name sp_section=
> > - .ifc \sp_section, function_section
> > - .section .text.__\name,"ax",%progbits
> > - .else
> > +.macro ARM_FUNC_START name
> > .text
> > - .endif
> > .globl SYM (__\name)
> > TYPE (__\name)
> > .align 0
> > @@ -2169,7 +2161,8 @@ LSYM(Lchange_\register):
> > .endm
> >
> > #ifndef __symbian__
> > -/* The condition here must match the one in gcc/config/arm/elf.h. */
> > +/* The condition here must match the one in gcc/config/arm/elf.h and
> > + libgcc/config/arm/t-elf. */
> > #ifndef NOT_ISA_TARGET_32BIT
> > #include "ieee754-df.S"
> > #include "ieee754-sf.S"
> > diff --git a/libgcc/config/arm/t-elf b/libgcc/config/arm/t-elf
> > index 9e7a3170f17..9da6cd37054 100644
> > --- a/libgcc/config/arm/t-elf
> > +++ b/libgcc/config/arm/t-elf
> > @@ -1,3 +1,19 @@
> > +ifeq (,$(findstring __symbian__,$(shell $(gcc_compile_bare) -dM -E -
> > </dev/null)))
> > +
> > +ARM_ISA:=$(findstring __ARM_ARCH_ISA_ARM,$(shell $(gcc_compile_bare) -dM
> > -E - </dev/null))
> > +THUMB1_ISA:=$(findstring __ARM_ARCH_ISA_THUMB 1,$(shell
> > $(gcc_compile_bare) -dM -E - </dev/null))
> > +
> > +# The condition here must match the one in gcc/config/arm/elf.h and
> > +# libgcc/config/arm/lib1funcs.S. _arm_muldf3 and _arm_mulsf3 must be
> > included
> > +# first so that the weak multiplication symbols in the corresponding files
> > are
> > +# chosen over the global symbols that _arm_muldivdf3 and _arm_muldivsf3
> > +# inclusion create when only multiplication is used, thus avoiding pulling
> > in
> > +# useless division code.
> > +ifneq (__ARM_ARCH_ISA_THUMB 1,$(ARM_ISA)$(THUMB1_ISA))
> > +LIB1ASMFUNCS += _arm_muldf3 _arm_mulsf3
> > +endif
> > +endif # !__symbian__
> > +
> > # For most CPUs we have an assembly soft-float implementations.
> > # However this is not true for ARMv6M. Here we want to use the soft-fp C
> > # implementation. The soft-fp code is only build for ARMv6M. This pulls
> >
>
