Hi,
When I was playing around where lowering of bit-field accesses go in
the pass order, I found that DOM had the same issue as PRE had when it
came to comparing BIT_INSERT_EXPR for equality. The same exact
testcase was showing the wrong code; gcc.dg/tree-ssa/20040324-1.c.
This fixes DOM the same way as I had fixed PRE, by special casing
BIT_INSERT_EXPR due to the implicit operand.
OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions.
Thanks,
Andrew Pinski
ChangeLog:
* tree-ssa-scopedtables.c (hashable_expr_equal_p): Check
BIT_INSERT_EXPR's operand 1
to see if the types precision matches.
Index: tree-ssa-scopedtables.c
===================================================================
--- tree-ssa-scopedtables.c (revision 250712)
+++ tree-ssa-scopedtables.c (working copy)
@@ -502,6 +502,16 @@ hashable_expr_equal_p (const struct hash
expr1->ops.ternary.opnd2, 0))
return false;
+ /* BIT_INSERT_EXPR has an implict operand as the type precision
+ of op1. Need to check to make sure they are the same. */
+ if (expr0->ops.ternary.op == BIT_INSERT_EXPR
+ && TREE_CODE (expr0->ops.ternary.opnd1) == INTEGER_CST
+ && TREE_CODE (expr1->ops.ternary.opnd1) == INTEGER_CST
+ && TYPE_PRECISION (TREE_TYPE (expr0->ops.ternary.opnd1))
+ != TYPE_PRECISION (TREE_TYPE (expr1->ops.ternary.opnd1)))
+ return false;
+
+
if (operand_equal_p (expr0->ops.ternary.opnd0,
expr1->ops.ternary.opnd0, 0)
&& operand_equal_p (expr0->ops.ternary.opnd1,
