[Bug regression/42282] New: regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[Bug regression/42282] New: regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[matt at use dot net]

With 20091201 trunk on Linux/amd64 ICE does not happen with GCC 4.4.1-ubuntu8.
Appears to be bad interaction 
between -O2 and -funswitch-loops. Either alone is fine, but together the crash
occurs. The commandline below reproduces the issue, but removing all but -O2
and -funswitch-loops will also reproduce.

gcc -c  -g -fkeep-inline-functions -DIN_GCC   -W -Wall -Wwrite-strings
-Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wmissing-format-attribute
-pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings
-Wold-style-definition -Wc++-compat -fno-common  -DHAVE_CONFIG_H -I. -I.
-I../../gcc-trunk/gcc -I../../gcc-trunk/gcc/. -I../../gcc-trunk/gcc/../include
-I../../gcc-trunk/gcc/../libcpp/include  -I../../gcc-trunk/gcc/../libdecnumber
-I../../gcc-trunk/gcc/../libdecnumber/bid -I../libdecnumber 
-DCLOOG_PPL_BACKEND  -I/usr/include/libelf -O2 -floop-interchange
-floop-strip-mine -floop-block -findirect-inlining -ftree-switch-conversion
-fvect-cost-model -fgcse-sm -fgcse-las -fgcse-after-reload -fsee
-ftree-loop-linear -ftree-loop-distribution -ftree-loop-im -ftree-loop-ivcanon
-fivopts -fvpt -funroll-loops -funswitch-loops
../../gcc-trunk/gcc/simplify-rtx.c -o simplify-rtx.o
../../gcc-trunk/gcc/simplify-rtx.c: In function
‘simplify_immed_subreg’:
../../gcc-trunk/gcc/simplify-rtx.c:4829:1: error: definition in block 35 does
not dominate use in block 131
for SSA_NAME: vp_549 in statement:
# DEBUG vp => vp_549 + 1
../../gcc-trunk/gcc/simplify-rtx.c:4829:1: internal compiler error: verify_ssa
failed


-- 
           Summary: regression: ICE when bootstrapping trunk with -O2 -
                    funswitch-loops
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: regression
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: matt at use dot net
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[jakub at gcc dot gnu dot org]

------- Comment #1 from jakub at gcc dot gnu dot org  2009-12-07 17:23 -------
Can't reproduce.  Please provide preprocessed source.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[matt at use dot net]

------- Comment #2 from matt at use dot net  2009-12-07 20:40 -------
Pre-processed output attached. I'm having some trouble getting it to crash
consistently, but here is the valgrind output that might indicate the problem: 

==26996== Conditional jump or move depends on uninitialised value(s)            
==26996==    at 0x70AA99: execute_rtl_store_motion (store-motion.c:271)         
==26996==    by 0x66A091: execute_one_pass (passes.c:1543)                      
==26996==    by 0x66A3A4: execute_pass_list (passes.c:1598)                     
==26996==    by 0x66A3C1: execute_pass_list (passes.c:1599)                     
==26996==    by 0x756D84: tree_rest_of_compilation (tree-optimize.c:413)        
==26996==    by 0x8ACC7A: cgraph_expand_function (cgraphunit.c:1495)            
==26996==    by 0x8AE9C3: cgraph_optimize (cgraphunit.c:1574)                   
==26996==    by 0x8AECE4: cgraph_finalize_compilation_unit (cgraphunit.c:1083)  
==26996==    by 0x41DA4A: c_write_global_declarations (c-decl.c:9489)           
==26996==    by 0x70E683: toplev_main (toplev.c:1061)                           
==26996==    by 0x6561ABC: (below main) (libc-start.c:220)                      
==26996==  Uninitialised value was created by a heap allocation                 
==26996==    at 0x4C25153: malloc (vg_replace_malloc.c:195)                     
==26996==    by 0xB93B4D: xmalloc (xmalloc.c:147)                               
==26996==    by 0x70A932: execute_rtl_store_motion (store-motion.c:1066)        
==26996==    by 0x66A091: execute_one_pass (passes.c:1543)                      
==26996==    by 0x66A3A4: execute_pass_list (passes.c:1598)                     
==26996==    by 0x66A3C1: execute_pass_list (passes.c:1599)                     
==26996==    by 0x756D84: tree_rest_of_compilation (tree-optimize.c:413)        
==26996==    by 0x8ACC7A: cgraph_expand_function (cgraphunit.c:1495)            
==26996==    by 0x8AE9C3: cgraph_optimize (cgraphunit.c:1574)                   
==26996==    by 0x8AECE4: cgraph_finalize_compilation_unit (cgraphunit.c:1083)  
==26996==    by 0x41DA4A: c_write_global_declarations (c-decl.c:9489)           
==26996==    by 0x70E683: toplev_main (toplev.c:1061)                           


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[matt at use dot net]

------- Comment #3 from matt at use dot net  2009-12-07 20:41 -------
Created an attachment (id=19252)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=19252&action=view)
pre-processed source

pre-processed source


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[zsojka at seznam dot cz]

------- Comment #4 from zsojka at seznam dot cz  2009-12-07 22:16 -------
(In reply to comment #2)
> Pre-processed output attached. I'm having some trouble getting it to crash
> consistently, but here is the valgrind output that might indicate the problem: 

Those warnings are caused by -fgcse-sm, see pr41862

(I tried to reproduce this issue with r154886, but failed)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2010-01-19 09:14 -------
Please retry with current trunk, there have been many fixes recently.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282

[Bug regression/42282] regression: ICE when bootstrapping trunk with -O2 -funswitch-loops

[jakub at gcc dot gnu dot org]

------- Comment #6 from jakub at gcc dot gnu dot org  2010-02-19 13:23 -------
Assuming this is fixed.  Please reopen if it is not.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|                            |WORKSFORME


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42282