[Bug c/16834] New: huge compilation time increase from 3.2.3 to 3.3.2

["jozef dot kruger at philips dot com" <gcc-bugzilla at gcc dot gnu dot org>]

I noticed that moving from gcc 3.2.3 to gcc 3.3.2 made compilation time of files
with huge expressions increase by a lot.
What we compile here are simulators for our processors and those programs can
include huge expressions. Attached to this email you'll find a file that
contains a number of expressions of almost 80.000 characters. (it has been
preprocessed and can be easily compiled with: gcc -c -xc toplevel.s.i )

The problem is that with 3.2.3 compilation takes 32 seconds:
  time gcc -c -xc toplevel.s.i 
    gcc -c -xc toplevel.s.i  31.17s user 0.66s system 99% cpu 32.001 total
With 3.3.2 it takes 38 minutes:
  time ggcc -c -xc toplevel.s.i
    gcc -c -xc toplevel.s.i  2269.29s user 4.87s system 99% cpu 38:04.19 total

The system was an Intel(R) Xeon(TM) CPU 2.80GHz with 4gb memory...

I gzipped the file because the src was 4.7M, the gzipped one is only 112k :)
gcc -v:
Reading specs from /cadappl/gcc/3.3.2/lib/gcc-lib/i686-pc-linux-gnu/3.3.2/specs
Configured with: /home/hooft/Level/Work/gcc/gcc-3.3.2/gcc-3.3.2/configure
--prefix=/cadappl/gcc/3.3.2 --enable-shared --enable-languages=c,c++,f77
--enable-__cxa_atexit --with-as=/cadappl/binutils/2.13.2/bin/as
--with-ld=/cadappl/binutils/2.13.2/bin/ld
--with-as=/cadappl/binutils/2.13.2/bin/as --with-ld=/cadappl/binutils/2.13.2/bin/ld
Thread model: posix
gcc version 3.3.2

-- 
           Summary: huge compilation time increase from 3.2.3 to 3.3.2
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jozef dot kruger at philips dot com
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16834