Bootstrapped and tested on x86_64-unknown-linux-gnu.
Richard.
2018-02-08 Richard Biener <rguent...@suse.de>
PR tree-optimization/84233
* tree-ssa-phiprop.c (propagate_with_phi): Use separate
changed flag instead of boguously re-using phi_inserted.
* g++.dg/torture/pr84233.C: New testcase.
Index: gcc/tree-ssa-phiprop.c
===================================================================
--- gcc/tree-ssa-phiprop.c (revision 257445)
+++ gcc/tree-ssa-phiprop.c (working copy)
@@ -270,6 +270,7 @@ propagate_with_phi (basic_block bb, gphi
use_operand_p arg_p, use;
ssa_op_iter i;
bool phi_inserted;
+ bool changed;
tree type = NULL_TREE;
if (!POINTER_TYPE_P (TREE_TYPE (ptr))
@@ -317,6 +318,7 @@ propagate_with_phi (basic_block bb, gphi
/* Replace the first dereference of *ptr if there is one and if we
can move the loads to the place of the ptr phi node. */
phi_inserted = false;
+ changed = false;
FOR_EACH_IMM_USE_STMT (use_stmt, ui, ptr)
{
gimple *def_stmt;
@@ -403,7 +405,7 @@ propagate_with_phi (basic_block bb, gphi
unlink_stmt_vdef (use_stmt);
gsi_remove (&gsi, true);
- phi_inserted = true;
+ changed = true;
}
/* Found a proper dereference. Insert a phi node if this
@@ -424,6 +426,7 @@ propagate_with_phi (basic_block bb, gphi
gsi_remove (&gsi, true);
phi_inserted = true;
+ changed = true;
}
else
{
@@ -431,13 +434,14 @@ propagate_with_phi (basic_block bb, gphi
load. */
gimple_assign_set_rhs1 (use_stmt, res);
update_stmt (use_stmt);
+ changed = true;
}
next:;
/* Continue searching for a proper dereference. */
}
- return phi_inserted;
+ return changed;
}
/* Main entry for phiprop pass. */
Index: gcc/testsuite/g++.dg/torture/pr84233.C
===================================================================
--- gcc/testsuite/g++.dg/torture/pr84233.C (revision 0)
+++ gcc/testsuite/g++.dg/torture/pr84233.C (working copy)
@@ -0,0 +1,25 @@
+// { dg-do compile }
+// { dg-additional-options "-w" }
+
+void a(const char *, int, const char *, const char *);
+template <typename b> void c(b);
+struct d {
+ long e;
+ template <typename> union f;
+ template <typename h> union f<h *> {
+ f(h *i) : j(i) {}
+ h *j;
+ long bits;
+ };
+ static int k(volatile long &i) { return *(int *)f<volatile long
*>(&i).bits; }
+ typedef long g;
+ operator g() volatile {
+ int l = k(e);
+ c(l);
+ }
+};
+struct : d {
+ } m, n;
+bool o;
+void p() { (o ? m : n) ? (void)0 : a("", 5, "", ""); }
+
