[PATCH][match-and-simplify] Do not match loads

[Richard Biener]

This avoids matching loads in the signle-rhs matching logic.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.

Richard.

2014-08-21  Richard Biener  <rguent...@suse.de>

        * genmatch.c (dt_operand::gen_gimple_expr): Only match
        non-reference-like GIMPLE single RHS.

Index: gcc/genmatch.c
===================================================================
--- gcc/genmatch.c      (revision 214225)
+++ gcc/genmatch.c      (working copy)
@@ -1297,8 +1297,19 @@ dt_operand::gen_gimple_expr (FILE *f)
        {
          if (*id == REALPART_EXPR || *id == IMAGPART_EXPR
              || *id == BIT_FIELD_REF || *id == VIEW_CONVERT_EXPR)
-           fprintf (f, "tree %s = TREE_OPERAND (gimple_assign_rhs1 (def_stmt), 
%i);\n",
-                    child_opname, i);
+           {
+             /* ???  If this is a memory operation we can't (and should not)
+                match this.  The only sensible operand types are
+                SSA names and invariants.  */
+             fprintf (f, "tree %s = TREE_OPERAND (gimple_assign_rhs1 
(def_stmt), %i);\n",
+                      child_opname, i);
+             fprintf (f, "if ((TREE_CODE (%s) == SSA_NAME\n"
+                      "&& (%s = do_valueize (valueize, %s)))\n"
+                      "|| is_gimple_min_invariant (%s))\n"
+                      "{\n", child_opname, child_opname, child_opname,
+                      child_opname);
+             continue;
+           }
          else
            fprintf (f, "tree %s = gimple_assign_rhs%u (def_stmt);\n",
                     child_opname, i + 1);