This backports a piece of
2012-09-24 Richard Guenther <rguent...@suse.de>
* tree-ssa-pre.c (bitmap_find_leader, create_expression_by_pieces,
find_or_generate_expression): Remove dominating stmt argument.
(find_leader_in_sets, phi_translate_1, bitmap_find_leader,
create_component_ref_by_pieces_1, create_component_ref_by_pieces,
do_regular_insertion, do_partial_partial_insertion): Adjust.
(compute_avail): Do not set uids.
to the 4.7 branch.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to
the branch (and the testcase added to 4.8, 4.9 and trunk).
Richard.
2014-05-06 Richard Biener <rguent...@suse.de>
PR tree-optimization/57864
* tree-ssa-pre.c (phi_translate_1): Backport NAME case
simplification from mainline. Do not lookup the VN
value-number here.
* gcc.dg/torture/pr57864.c: New testcase.
Index: gcc/tree-ssa-pre.c
===================================================================
*** gcc/tree-ssa-pre.c (revision 210104)
--- gcc/tree-ssa-pre.c (working copy)
*************** phi_translate_1 (pre_expr expr, bitmap_s
*** 1756,1794 ****
case NAME:
{
- gimple phi = NULL;
- edge e;
- gimple def_stmt;
tree name = PRE_EXPR_NAME (expr);
!
! def_stmt = SSA_NAME_DEF_STMT (name);
if (gimple_code (def_stmt) == GIMPLE_PHI
&& gimple_bb (def_stmt) == phiblock)
- phi = def_stmt;
- else
- return expr;
-
- e = find_edge (pred, gimple_bb (phi));
- if (e)
{
! tree def = PHI_ARG_DEF (phi, e->dest_idx);
! pre_expr newexpr;
!
! if (TREE_CODE (def) == SSA_NAME)
! def = VN_INFO (def)->valnum;
/* Handle constant. */
if (is_gimple_min_invariant (def))
return get_or_alloc_expr_for_constant (def);
! if (TREE_CODE (def) == SSA_NAME && ssa_undefined_value_p (def))
! return NULL;
!
! newexpr = get_or_alloc_expr_for_name (def);
! return newexpr;
}
}
- return expr;
default:
gcc_unreachable ();
--- 1756,1781 ----
case NAME:
{
tree name = PRE_EXPR_NAME (expr);
! gimple def_stmt = SSA_NAME_DEF_STMT (name);
! /* If the SSA name is defined by a PHI node in this block,
! translate it. */
if (gimple_code (def_stmt) == GIMPLE_PHI
&& gimple_bb (def_stmt) == phiblock)
{
! edge e = find_edge (pred, gimple_bb (def_stmt));
! tree def = PHI_ARG_DEF (def_stmt, e->dest_idx);
/* Handle constant. */
if (is_gimple_min_invariant (def))
return get_or_alloc_expr_for_constant (def);
! return get_or_alloc_expr_for_name (def);
}
+ /* Otherwise return it unchanged - it will get cleaned if its
+ value is not available in PREDs AVAIL_OUT set of expressions. */
+ return expr;
}
default:
gcc_unreachable ();
Index: gcc/testsuite/gcc.dg/torture/pr57864.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr57864.c (revision 0)
--- gcc/testsuite/gcc.dg/torture/pr57864.c (working copy)
***************
*** 0 ****
--- 1,37 ----
+ /* { dg-do compile } */
+
+ union U {
+ double val;
+ union U *ptr;
+ };
+
+ union U *d;
+ double a;
+ int b;
+ int c;
+
+ static void fn1(union U *p1, int p2, _Bool p3)
+ {
+ union U *e;
+
+ if (p2 == 0)
+ a = ((union U*)((unsigned long)p1 & ~1))->val;
+
+ if (b) {
+ e = p1;
+ } else if (c) {
+ e = ((union U*)((unsigned long)p1 & ~1))->ptr;
+ d = e;
+ } else {
+ e = 0;
+ d = ((union U*)0)->ptr;
+ }
+
+ fn1 (e, 0, 0);
+ fn1 (0, 0, p3);
+ }
+
+ void fn2 (void)
+ {
+ fn1 (0, 0, 0);
+ }
