[Bug tree-optimization/68552] New: [6 Regression]: ICE in in expand_expr_real_2 with -O2 -ftree-vectorize

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68552

            Bug ID: 68552
           Summary: [6 Regression]: ICE in in expand_expr_real_2 with -O2
                    -ftree-vectorize
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ubizjak at gmail dot com
  Target Milestone: ---
            Target: alpha-linux-gnu

Recent regression on alpha-linux-gnu:

FAIL: gcc.c-torture/compile/pr52255.c   -O3

This ICE can be triggered with a crosscompiler to alpha-linux-gnu with '-O2
-ftree-vectorize':

Starting program: /home/uros/gcc-build-alpha/gcc/cc1 -O2 -ftree-vectorize
-quiet -fpreprocessed pr52255.c

Breakpoint 1, internal_error (gmsgid=0x12a0c4c "in %s, at %s:%d") at
../../gcc-svn/trunk/gcc/diagnostic.c:1255
1255    internal_error (const char *gmsgid, ...)
(gdb) bt
#0  internal_error (gmsgid=0x12a0c4c "in %s, at %s:%d") at
../../gcc-svn/trunk/gcc/diagnostic.c:1255
#1  0x00000000010bf6cc in fancy_abort (file=<optimized out>, line=9260, 
    function=0x1185a40 <expand_expr_real_2(separate_ops*, rtx_def*,
machine_mode, expand_modifier)::__FUNCTION__> "expand_expr_real_2")
    at ../../gcc-svn/trunk/gcc/diagnostic.c:1332
#2  0x0000000000790930 in expand_expr_real_2 (ops=0x7fffffffbdb0,
target=<optimized out>, tmode=<optimized out>, modifier=EXPAND_NORMAL)
    at ../../gcc-svn/trunk/gcc/expr.c:9260
#3  0x0000000000685b5f in expand_gimple_stmt_1 (stmt=0x2aaaae88e300) at
../../gcc-svn/trunk/gcc/cfgexpand.c:3628
#4  0x0000000000685e87 in expand_gimple_stmt (stmt=0x2aaaae88e300) at
../../gcc-svn/trunk/gcc/cfgexpand.c:3688

(gdb) f 2
#2  0x0000000000790930 in expand_expr_real_2 (ops=0x7fffffffbdb0,
target=<optimized out>, tmode=<optimized out>, modifier=EXPAND_NORMAL)
    at ../../gcc-svn/trunk/gcc/expr.c:9260
9260          gcc_assert (temp);
(gdb) list
9255            }
9256          else
9257            gcc_assert (GET_MODE_CLASS (GET_MODE (op2)) ==
MODE_VECTOR_INT);
9258
9259          temp = expand_vec_perm (mode, op0, op1, op2, target);
9260          gcc_assert (temp);
9261          return temp;
9262
9263        case DOT_PROD_EXPR:
9264          {