Re: Patch to gcc/Makefile.in for fastcompare* targets [take 2]

["Mark Mitchell" <mark at codesourcery dot com>]

Since there's been no other comment, I'll approve this patch.

Thanks,

-- Mark

----- Original Message ----- 
From: "Kaveh R. Ghazi" <ghazi@caip.rutgers.edu>
To: <gcc-patches@gcc.gnu.org>
Sent: Friday, September 19, 2003 10:16 PM
Subject: Patch to gcc/Makefile.in for fastcompare* targets [take 2]


> Looking at my previous fastcompare* patch:
> http://gcc.gnu.org/ml/gcc-patches/2003-09/msg00752.html
>
> I observed that the skeleton of the "compare" shell fragments was
> identical among the "slow", "gnu" and my new "fast" variant.  There is
> no need to repeat it three times.  I merged them all into one to make
> it more maintainable by inserting a case stmt inside the for loops to
> fork off the appropriate cmp magic based on $@.
>
> Tested by running make gnucompare slowcompare fastcompare and compare
> in the gcc directory.  I also tweeked a random .o file to simulate an
> error and reran all four targets to ensure they trap the compare
> failure.  (They did.)
>
> I used a context diff 'cause it was slightly easier to read than the
> unified diff format in this case.
>
> Ok for mainline?
>
> Thanks,
> --Kaveh
>
>
> 2003-09-11  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
>
> * Makefile.in (gnucompare*): Merge into ...
> (slowcompare*): ... here.
> (fastcompare*): New targets.
> * aclocal.m4 (gcc_AC_PROG_CMP_IGNORE_INITIAL): Add checks for
> other "fast" cmp programs.
> * configure: Regenerate.
>
> diff -rcp orig/egcc-CVS20030919/gcc/Makefile.in
egcc-CVS20030919/gcc/Makefile.in
> *** orig/egcc-CVS20030919/gcc/Makefile.in Sun Sep 14 20:00:59 2003
> --- egcc-CVS20030919/gcc/Makefile.in Sat Sep 20 00:47:03 2003
> *************** restrap:
> *** 3529,3590 ****
>   $(MAKE) unstrap
>   $(MAKE) $(REMAKEFLAGS) bootstrap
>
> ! # Compare the object files in the current directory with those in the
> ! # stage2 directory.
> ! # ./ avoids bug in some versions of tail.
> ! slowcompare slowcompare3 slowcompare4 slowcompare-lean slowcompare3-lean
slowcompare4-lean: force
>   -rm -f .bad_compare
> ! case "$@" in slowcompare | slowcompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^slowcompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   for file in *$(objext); do \
> !   tail +16c ./$$file > tmp-foo1; \
> !   tail +16c stage$$stage/$$file > tmp-foo2 \
> !     && (cmp tmp-foo1 tmp-foo2 > /dev/null 2>&1 || echo $$file differs >>
.bad_compare) || true; \
> ! done
> ! case "$@" in slowcompare | slowcompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^slowcompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
> ! for dir in tmp-foo $(SUBDIRS); do \
> !   if [ "`echo $$dir/*$(objext)`" != "$$dir/*$(objext)" ] ; then \
> !     for file in $$dir/*$(objext); do \
>         tail +16c ./$$file > tmp-foo1; \
>         tail +16c stage$$stage/$$file > tmp-foo2 \
>           && (cmp tmp-foo1 tmp-foo2 > /dev/null 2>&1 || echo $$file
differs >> .bad_compare) || true; \
> !     done; \
> !   else true; fi; \
> ! done
> ! -rm -f tmp-foo*
> ! case "$@" in slowcompare | slowcompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^slowcompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
> ! if [ -f .bad_compare ]; then \
> !   echo "Bootstrap comparison failure!"; \
> !   cat .bad_compare; \
> !   exit 1; \
> ! else \
> !   case "$@" in \
> !     *-lean ) rm -rf stage$$stage ;; \
> !     *) ;; \
> !   esac; true; \
> ! fi
> !
> ! # Compare the object files in the current directory with those in the
> ! # stage2 directory.  Use gnu cmp (diffutils v2.4 or later) to avoid
> ! # running tail and the overhead of twice copying each object file.
> ! # An exit status of 1 is precisely the result we're looking for (other
> ! # values mean other problems).
> ! gnucompare gnucompare3 gnucompare4 gnucompare-lean gnucompare3-lean
gnucompare4-lean: force
> ! -rm -f .bad_compare
> ! case "$@" in gnucompare | gnucompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^gnucompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
> ! for file in *$(objext); do \
> !   cmp --ignore-initial=16 $$file stage$$stage/$$file > /dev/null 2>&1; \
> !   test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
>   done
> ! case "$@" in gnucompare | gnucompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^gnucompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   for dir in tmp-foo $(SUBDIRS); do \
>     if [ "`echo $$dir/*$(objext)`" != "$$dir/*$(objext)" ] ; then \
>       for file in $$dir/*$(objext); do \
> !       cmp --ignore-initial=16 $$file stage$$stage/$$file > /dev/null
2>&1; \
> !       test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
>       done; \
>     else true; fi; \
>   done
> ! case "$@" in gnucompare | gnucompare-lean ) stage=2 ;; * ) stage=`echo
$@ | sed -e 's,^gnucompare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   if [ -f .bad_compare ]; then \
>     echo "Bootstrap comparison failure!"; \
>     cat .bad_compare; \
> --- 3529,3590 ----
>   $(MAKE) unstrap
>   $(MAKE) $(REMAKEFLAGS) bootstrap
>
> ! # These targets compare the object files in the current directory with
> ! # those in a stage directory.  We need to skip the first N bytes of
> ! # each object file.  The "slow" mechanism assumes nothing special
> ! # about cmp and uses the tail command to skip.  ./ avoids a bug in
> ! # some versions of tail.  The "gnu" targets use gnu cmp (diffutils
> ! # v2.4 or later), to avoid running tail and the overhead of twice
> ! # copying each object file.  Likewise, the "fast" targets use the skip
> ! # parameter of cmp available on some systems to accomplish the same
> ! # thing.  An exit status of 1 is precisely the result we're looking
> ! # for (other values mean other problems).
> ! slowcompare slowcompare3 slowcompare4 slowcompare-lean slowcompare3-lean
slowcompare4-lean \
> ! fastcompare fastcompare3 fastcompare4 fastcompare-lean fastcompare3-lean
fastcompare4-lean \
> !  gnucompare  gnucompare3  gnucompare4  gnucompare-lean  gnucompare3-lean
gnucompare4-lean: force
>   -rm -f .bad_compare
> ! case "$@" in *compare | *compare-lean ) stage=2 ;; * ) stage=`echo $@ |
sed -e 's,^[a-z]*compare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   for file in *$(objext); do \
> !   case "$@" in \
> !     slowcompare* ) \
>         tail +16c ./$$file > tmp-foo1; \
>         tail +16c stage$$stage/$$file > tmp-foo2 \
>           && (cmp tmp-foo1 tmp-foo2 > /dev/null 2>&1 || echo $$file
differs >> .bad_compare) || true; \
> !       ;; \
> !     fastcompare* ) \
> !       cmp $$file stage$$stage/$$file 16 16 > /dev/null 2>&1; \
> !       test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
> !       ;; \
> !     gnucompare* ) \
> !       cmp --ignore-initial=16 $$file stage$$stage/$$file > /dev/null
2>&1; \
> !       test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
> !       ;; \
> !   esac ; \
>   done
> ! case "$@" in *compare | *compare-lean ) stage=2 ;; * ) stage=`echo $@ |
sed -e 's,^[a-z]*compare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   for dir in tmp-foo $(SUBDIRS); do \
>     if [ "`echo $$dir/*$(objext)`" != "$$dir/*$(objext)" ] ; then \
>       for file in $$dir/*$(objext); do \
> !       case "$@" in \
> ! slowcompare* ) \
> !   tail +16c ./$$file > tmp-foo1; \
> !   tail +16c stage$$stage/$$file > tmp-foo2 \
> !     && (cmp tmp-foo1 tmp-foo2 > /dev/null 2>&1 || echo $$file differs >>
.bad_compare) || true; \
> !   ;; \
> ! fastcompare* ) \
> !   cmp $$file stage$$stage/$$file 16 16 > /dev/null 2>&1; \
> !   test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
> !   ;; \
> ! gnucompare* ) \
> !   cmp --ignore-initial=16 $$file stage$$stage/$$file > /dev/null 2>&1; \
> !   test $$? -eq 1 && echo $$file differs >> .bad_compare || true; \
> !   ;; \
> !       esac ; \
>       done; \
>     else true; fi; \
>   done
> ! -rm -f tmp-foo*
> ! case "$@" in *compare | *compare-lean ) stage=2 ;; * ) stage=`echo $@ |
sed -e 's,^[a-z]*compare\([0-9][0-9]*\).*,\1,'` ;; esac; \
>   if [ -f .bad_compare ]; then \
>     echo "Bootstrap comparison failure!"; \
>     cat .bad_compare; \
> *************** gnucompare gnucompare3 gnucompare4 gnuco
> *** 3592,3597 ****
> --- 3592,3598 ----
>   else \
>     case "$@" in \
>       *-lean ) rm -rf stage$$stage ;; \
> +     *) ;; \
>     esac; true; \
>   fi
>
> diff -rcp orig/egcc-CVS20030919/gcc/aclocal.m4
egcc-CVS20030919/gcc/aclocal.m4
> *** orig/egcc-CVS20030919/gcc/aclocal.m4 Tue Aug 12 20:01:43 2003
> --- egcc-CVS20030919/gcc/aclocal.m4 Sat Sep 20 00:41:12 2003
> *************** fi
> *** 104,122 ****
>   dnl 'make compare' can be significantly faster, if cmp itself can
>   dnl skip bytes instead of using tail.  The test being performed is
>   dnl "if cmp --ignore-initial=2 t1 t2 && ! cmp --ignore-initial=1 t1 t2"
> ! dnl but we need to sink errors and handle broken shells.
>   AC_DEFUN(gcc_AC_PROG_CMP_IGNORE_INITIAL,
>   [AC_CACHE_CHECK([for cmp's capabilities], gcc_cv_prog_cmp_skip,
>   [ echo abfoo >t1
>     echo cdfoo >t2
>     if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then
>       if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; then
> !       gcc_cv_prog_cmp_skip=slowcompare
>       else
>         gcc_cv_prog_cmp_skip=gnucompare
>       fi
> !   else
> !     gcc_cv_prog_cmp_skip=slowcompare
>     fi
>     rm t1 t2
>   ])
> --- 104,132 ----
>   dnl 'make compare' can be significantly faster, if cmp itself can
>   dnl skip bytes instead of using tail.  The test being performed is
>   dnl "if cmp --ignore-initial=2 t1 t2 && ! cmp --ignore-initial=1 t1 t2"
> ! dnl but we need to sink errors and handle broken shells.  We also test
> ! dnl for the parameter format "cmp file1 file2 skip1 skip2" which is
> ! dnl accepted by cmp on some systems.
>   AC_DEFUN(gcc_AC_PROG_CMP_IGNORE_INITIAL,
>   [AC_CACHE_CHECK([for cmp's capabilities], gcc_cv_prog_cmp_skip,
>   [ echo abfoo >t1
>     echo cdfoo >t2
> +   gcc_cv_prog_cmp_skip=slowcompare
>     if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then
>       if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; then
> !       :
>       else
>         gcc_cv_prog_cmp_skip=gnucompare
>       fi
> !   fi
> !   if test $gcc_cv_prog_cmp_skip = slowcompare ; then
> !     if cmp t1 t2 2 2 > /dev/null 2>&1; then
> !       if cmp t1 t2 1 1 > /dev/null 2>&1; then
> !         :
> !       else
> !         gcc_cv_prog_cmp_skip=fastcompare
> !       fi
> !     fi
>     fi
>     rm t1 t2
>   ])
>