[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 --- Comment #10 from Jakub Jelinek jakub at gcc dot gnu.org --- Author: jakub Date: Mon Mar 3 07:25:50 2014 New Revision: 208267 URL: http://gcc.gnu.org/viewcvs?rev=208267root=gccview=rev Log: PR middle-end/60175 * function.c (expand_function_end): Don't emit clobber_return_register sequence if clobber_after is a BARRIER. * cfgexpand.c (construct_exit_block): Append instructions before return_label to prev_bb. Modified: trunk/gcc/ChangeLog trunk/gcc/cfgexpand.c trunk/gcc/function.c
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 Jakub Jelinek jakub at gcc dot gnu.org changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED --- Comment #11 from Jakub Jelinek jakub at gcc dot gnu.org --- Should be fixed now.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 --- Comment #2 from Yury Gribov y.gribov at samsung dot com --- Created attachment 32132 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=32132action=edit Proposed patch So it looks like we are using wrong function here. Frequency does not need to have the same bounds as probability. I'm attaching a draft patch (only checked it for code in question).
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 Yury Gribov y.gribov at samsung dot com changed: What|Removed |Added CC||hubicka at gcc dot gnu.org, ||tejohnson at google dot com --- Comment #3 from Yury Gribov y.gribov at samsung dot com --- Adding Jan and Teresa (who worked on this piece of code) to comment on proposed patch.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 --- Comment #4 from Teresa Johnson tejohnson at google dot com --- On Fri, Feb 14, 2014 at 1:01 AM, y.gribov at samsung dot com gcc-bugzi...@gcc.gnu.org wrote: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 Yury Gribov y.gribov at samsung dot com changed: What|Removed |Added CC||hubicka at gcc dot gnu.org, ||tejohnson at google dot com --- Comment #3 from Yury Gribov y.gribov at samsung dot com --- Adding Jan and Teresa (who worked on this piece of code) to comment on proposed patch. The patch looks good to me, but I can't approve. The other calls to combine_probabilities from this module look ok to me, but this one should be apply_probability as you note. Thanks, Teresa -- You are receiving this mail because: You are on the CC list for the bug.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 --- Comment #5 from Yury Gribov y.gribov at samsung dot com --- Thanks, I'll run regtests on Monday and send patch for gcc-patches approve if all goes well.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 Jakub Jelinek jakub at gcc dot gnu.org changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #6 from Jakub Jelinek jakub at gcc dot gnu.org --- The bug is far before loop unrolling, I see the problem already during expansion, where the out of bound frequency 19992 is present.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 --- Comment #7 from Jakub Jelinek jakub at gcc dot gnu.org --- Even on x86_64 one can see the bogus frequencies like 2 when or 1999N when maximum is 1, but only in the epilogue blocks.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175
--- Comment #8 from Jakub Jelinek jakub at gcc dot gnu.org ---
The incorrect frequencies can be seen even on say -O1 -fsanitize=address
-fdump-rtl-expand-all:
static void *stack_base;
void mark_memory (void **start, void **end);
int
main (void)
{
void *dummy;
stack_base = dummy;
void *end;
mark_memory (stack_base, end);
return 0;
}
I don't see anything wrong before find_many_sub_blocks is called, there are
just 3 basic blocks at that point, bb3 as entry block successor with freq
1, which has some asan related branches inside of it, but nothing outside,
then bb2
as the function body block with freq 1, which ends in an unconditional jump
that jumps to return_label (in bb4 after note + 2 clobbers), and finally bb4 as
the exit block predecessor with freq 1. I guess the only weird thing is
that the clobbers are bypassed by the jump, maybe that in the end causes
find_many_sub_blocks to create weird frequencies. And bb4 contains again some
conditional jumps and labels related to asan, but again only inside that block.
Without asan use-after-return, the exit block predecessor is just merged with
the preceeding basic block, maybe it has a wrong frequency after
find_many_sub_blocks too, but as it is merged with the body block, tha twrong
frequency never shows up anywhere.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175
--- Comment #9 from Jakub Jelinek jakub at gcc dot gnu.org ---
--- gcc/function.c.jj2014-01-06 22:32:17.0 +0100
+++ gcc/function.c2014-02-14 19:05:27.233008179 +0100
@@ -5156,17 +5156,20 @@ expand_function_end (void)
crtl-return_rtx = outgoing;
}
- /* Emit the actual code to clobber return register. */
- {
-rtx seq;
+ /* Emit the actual code to clobber return register. Don't emit
+ it if clobber_after is a barrier, then the previous basic block
+ certainly doesn't fall thru into the exit block. */
+ if (!BARRIER_P (clobber_after))
+{
+ rtx seq;
-start_sequence ();
-clobber_return_register ();
-seq = get_insns ();
-end_sequence ();
+ start_sequence ();
+ clobber_return_register ();
+ seq = get_insns ();
+ end_sequence ();
-emit_insn_after (seq, clobber_after);
- }
+ emit_insn_after (seq, clobber_after);
+}
/* Output the label for the naked return from the function. */
if (naked_return_label)
fixes this for the common case of not falling through into the exit block, if
clobber_after is BARRIER, the clobbers will surely be never reachable and
immediately removed anyway.
Now, even with this patch we generate incorrect frequencies say for -O2
-fsanitize=address on:
int
foo (int i)
{
if (i)
return 4;
int j;
bar (j);
}
I think in that case we either need to stick the clobber stmts before the
return_label into the predecessor basic block, or create a new basic block to
hold just the clobbers and derive the frequency of the block containing the
clobbers from the frequency of the previous basic block.
[Bug middle-end/60175] ICE on gcc.dg/asan/nosanitize-and-inline.c
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60175 Yury Gribov y.gribov at samsung dot com changed: What|Removed |Added CC||y.gribov at samsung dot com --- Comment #1 from Yury Gribov y.gribov at samsung dot com --- I can reproduce this with trunk version. Build options are `-O2 -funroll-loops -fsanitize=address'.
