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Re: basic-block profiling
You're looking for -fprofile-arcs and -ftest-coverage in GCC 3.2; those
are the new block (edge, really) profiler.
On Mon, Oct 28, 2002 at 12:36:38PM -0600, Saisanthosh Balakrishnan wrote:
>
> Following up on my previous email, I just now saw an entry in
> Changelog:
>
> <quote>
> 2002-05-21 Richard Henderson <rth@redhat.com>
>
> * system.h (BLOCK_PROFILER, BLOCK_PROFILER_CODE,
> FUNCTION_BLOCK_PROFILER, FUNCTION_BLOCK_PROFILER_EXIT,
> MACHINE_STATE_SAVE, MACHINE_STATE_RESTORE): Poison.
>
> * toplev.c (display_help): Kill -a -ax help.
> ....
> </quote>
>
>
> Why was the code considered "poisonous"? Any other ways I could have
> basic-block profiling?
>
> -Sai
>
>
> > I've been using gcc's (3.0.3, Linux, x86) -a (basic-block profiling)
> > to get the execution frequency counts of basic blocks. "-ax", a
> > documented flag, that is supposed to provide jump address and bb
> > traces never worked for me. I get the following error with gcc -ax
> > simple.c:
> >
> > simple.c is the first example program in gcov's info page.
> > simple.c: In function `main':
> > simple.c:14: Unrecognizable insn:
> > (call_insn 92 91 93 (call (mem:QI (symbol_ref ("__bb_trace_ret")) 0)
> > (const_int 0 [0x0])) -1 (nil)
> > (nil)
> > (nil))
> > simple.c:14: Internal compiler error in insn_default_length, at
> > insn-attrtab.c:223
> > Please submit a full bug report,
> > with preprocessed source if appropriate.
> > See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
> >
> > I assumed that the support for basic-block profiling was in initial
> > stages in gcc-3.0.3, and downloaded gcc-3.2. I was surprised, when gcc
> > reported -a and -ax as unsupported flags. I did not see any references
> > to these flags in toplev.c (libgcc2.c etc.). However, the flags are
> > documented in gcc-3.2 info page! Could the authors of profiling
> > (and/or basic-block profiling), respond as to what's going on, what I
> > could expect to see in future releases of gcc?
> >
> > Thanks in advance.
> > Sai
> >
>
--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer