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[PATCH] Fix PR80713
- From: Richard Biener <rguenther at suse dot de>
- To: gcc-patches at gcc dot gnu dot org
- Date: Fri, 12 May 2017 11:11:09 +0200 (CEST)
- Subject: [PATCH] Fix PR80713
- Authentication-results: sourceware.org; auth=none
The following fixes up my earlier change in PRE for fallout with the
intricate interaction of the two "DCE" algorithms in PRE...
Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
Richard.
2017-05-12 Richard Biener <rguenther@suse.de>
PR tree-optimization/80713
* tree-ssa-pre.c (remove_dead_inserted_code): Clear
inserted_exprs bit for not removed stmts.
* gcc.dg/torture/pr80713.c: New testcase.
Index: gcc/tree-ssa-pre.c
===================================================================
--- gcc/tree-ssa-pre.c (revision 247952)
+++ gcc/tree-ssa-pre.c (working copy)
@@ -4947,8 +4947,14 @@ remove_dead_inserted_code (void)
}
}
+ unsigned int to_clear = -1U;
EXECUTE_IF_SET_IN_BITMAP (inserted_exprs, 0, i, bi)
{
+ if (to_clear != -1U)
+ {
+ bitmap_clear_bit (inserted_exprs, to_clear);
+ to_clear = -1U;
+ }
t = SSA_NAME_DEF_STMT (ssa_name (i));
if (!gimple_plf (t, NECESSARY))
{
@@ -4969,7 +4975,14 @@ remove_dead_inserted_code (void)
release_defs (t);
}
}
+ else
+ /* eliminate_fini will skip stmts marked for removal if we
+ already removed it and uses inserted_exprs for this, so
+ clear those we didn't end up removing. */
+ to_clear = i;
}
+ if (to_clear != -1U)
+ bitmap_clear_bit (inserted_exprs, to_clear);
BITMAP_FREE (worklist);
}
Index: gcc/testsuite/gcc.dg/torture/pr80713.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr80713.c (revision 0)
+++ gcc/testsuite/gcc.dg/torture/pr80713.c (working copy)
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+
+int a, b, d, e, f;
+int *c;
+void g()
+{
+ for (;;)
+ {
+ if (*c) {
+ int h;
+ *c = &h;
+ } else
+ b = 0;
+ if (f)
+ *c = g;
+ else
+ for (; a; a++)
+ for (;;) {
+ if (d)
+ break;
+ c = e;
+ }
+ }
+}