Make get_value_for_expr check for INTEGER_CSTs

[Richard Sandiford]

CONSTANT lattice values are symbolic constants rather than
compile-time constants, so among other things can be POLY_INT_CSTs.
This patch fixes a case in which we assumed all CONSTANTs were either
ADDR_EXPRs or INTEGER_CSTs.

This is tested by later SVE patches.

Tested on aarch64-linux-gnu with SVE (with and without follow-on
patches) and x86_64-linux-gnu.  OK to install?

Richard


2019-09-18  Richard Sandiford  <richard.sandif...@arm.com>

gcc/
        * tree-ssa-ccp.c (get_value_for_expr): Check whether CONSTANTs
        are INTEGER_CSTs.

Index: gcc/tree-ssa-ccp.c
===================================================================
--- gcc/tree-ssa-ccp.c  2019-08-21 14:58:05.999057076 +0100
+++ gcc/tree-ssa-ccp.c  2019-09-18 07:53:36.930481545 +0100
@@ -615,9 +615,17 @@ get_value_for_expr (tree expr, bool for_
          val.mask = -1;
        }
       if (for_bits_p
-         && val.lattice_val == CONSTANT
-         && TREE_CODE (val.value) == ADDR_EXPR)
-       val = get_value_from_alignment (val.value);
+         && val.lattice_val == CONSTANT)
+       {
+         if (TREE_CODE (val.value) == ADDR_EXPR)
+           val = get_value_from_alignment (val.value);
+         else if (TREE_CODE (val.value) != INTEGER_CST)
+           {
+             val.lattice_val = VARYING;
+             val.value = NULL_TREE;
+             val.mask = -1;
+           }
+       }
       /* Fall back to a copy value.  */
       if (!for_bits_p
          && val.lattice_val == VARYING