[Bug tree-optimization/53550] New: [4.6/4.7/4.8 regression] ICE with -O{1,2,3} -fprefetch-loop-arrays in build2_stat, at tree.c:3803

[xarthisius.kk at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53550

             Bug #: 53550
           Summary: [4.6/4.7/4.8 regression] ICE with -O{1,2,3}
                    -fprefetch-loop-arrays in build2_stat, at tree.c:3803
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: xarthisius...@gmail.com


Created attachment 27538
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27538
reduced testcase

Starting program: /dev/shm/portage/sys-devel/gcc-4.6.3/work/build/gcc/cc1 -O2
-fprefetch-loop-arrays /ice_416991.i
 wctomb mbstowcs luma_render
/ice_416991.i: In function 'luma_render':
/ice_416991.i:28:20: warning: incompatible implicit declaration of built-in
function 'malloc' [enabled by default]

Analyzing compilation unit
Performing interprocedural optimizations
 <*free_lang_data> <visibility> <early_local_cleanups> <whole-program>
<ipa-profile> <cp> <inline> <pure-const> <static-var>Assembling functions:
 wctomb mbstowcs luma_render
Breakpoint 1, 0x00000000005ba3e4 in fancy_abort ()
(gdb) bt
#0  0x00000000005ba3e4 in fancy_abort ()
#1  0x00000000009bf92b in build2_stat ()
#2  0x000000000064370e in build2_stat_loc ()
#3  0x000000000067967c in fold_build2_stat_loc ()
#4  0x000000000091022c in determine_exit_conditions ()
#5  0x0000000000910549 in tree_transform_and_unroll_loop ()
#6  0x000000000091107c in tree_unroll_loop ()
#7  0x0000000000ddfc64 in loop_prefetch_arrays ()
#8  0x0000000000ddffc5 in tree_ssa_prefetch_arrays ()
#9  0x000000000091a47d in tree_ssa_loop_prefetch ()
#10 0x0000000000759059 in execute_one_pass ()
#11 0x0000000000759233 in execute_pass_list ()
#12 0x0000000000759254 in execute_pass_list ()
#13 0x0000000000759254 in execute_pass_list ()
#14 0x000000000088eae1 in tree_rest_of_compilation ()
#15 0x0000000000a49d0b in cgraph_expand_function ()
#16 0x0000000000a49eca in cgraph_expand_all_functions ()
#17 0x0000000000a4a533 in cgraph_optimize ()
#18 0x0000000000a48b22 in cgraph_finalize_compilation_unit ()
#19 0x000000000049de30 in c_write_global_declarations ()
#20 0x000000000083006e in compile_file ()
#21 0x0000000000832000 in do_compile ()
#22 0x0000000000832146 in toplev_main ()
#23 0x0000000000521118 in main ()

Downstream bug: https://bugs.gentoo.org/show_bug.cgi?id=416991

I've checked that it also fails with gcc-4.4.6, however it works fine with
gcc-4.5.3.