Hi!
Various places check that (ab) SSA_NAMEs that weren't referenced on a stmt
before don't appear on it, but all the checking is done on the gimple tuple
operands, while in this case it is added to operands of a comparison of
COND_EXPR/VEC_COND_EXPR. The following patch fixes it,
bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2016-01-07 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/69167
* gimple-match-head.c (gimple_simplify) <case GIMPLE_TERNARY_RHS>:
Don't simplify condition if the condition simplification would
introduce use of SSA_NAME_OCCURS_IN_ABNORMAL_PHI SSA_NAME not
previously mentioned on the insn.
* gimple-fold.h (has_use_on_stmt): New prototype.
* gimple-fold.c (has_use_on_stmt): No longer static.
* gcc.dg/pr69167.c: New test.
--- gcc/gimple-match-head.c.jj 2016-01-04 14:55:53.000000000 +0100
+++ gcc/gimple-match-head.c 2016-01-07 12:54:42.237334530 +0100
@@ -655,9 +655,23 @@ gimple_simplify (gimple *stmt,
valueized = true;
if (TREE_CODE_CLASS ((enum tree_code)rcode2)
== tcc_comparison)
- rhs1 = build2 (rcode2, TREE_TYPE (rhs1),
- ops2[0], ops2[1]);
- else if (rcode2 == SSA_NAME
+ {
+ if (TREE_CODE (ops2[0]) == SSA_NAME
+ && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ops2[0])
+ && !has_use_on_stmt (ops2[0], stmt))
+ valueized = false;
+ if (TREE_CODE (ops2[1]) == SSA_NAME
+ && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ops2[1])
+ && !has_use_on_stmt (ops2[1], stmt))
+ valueized = false;
+ if (valueized)
+ rhs1 = build2 (rcode2, TREE_TYPE (rhs1),
+ ops2[0], ops2[1]);
+ }
+ else if ((rcode2 == SSA_NAME
+ && (!SSA_NAME_OCCURS_IN_ABNORMAL_PHI
+ (ops2[0])
+ || has_use_on_stmt (ops2[0], stmt)))
|| rcode2 == INTEGER_CST
|| rcode2 == VECTOR_CST)
rhs1 = ops2[0];
--- gcc/gimple-fold.h.jj 2016-01-04 14:55:53.000000000 +0100
+++ gcc/gimple-fold.h 2016-01-07 13:01:52.938315972 +0100
@@ -34,6 +34,7 @@ extern tree maybe_fold_or_comparisons (e
enum tree_code, tree, tree);
extern bool arith_overflowed_p (enum tree_code, const_tree, const_tree,
const_tree);
+extern bool has_use_on_stmt (tree, gimple *);
extern tree no_follow_ssa_edges (tree);
extern tree follow_single_use_edges (tree);
extern tree gimple_fold_stmt_to_constant_1 (gimple *, tree (*) (tree),
--- gcc/gimple-fold.c.jj 2016-01-07 11:37:36.000000000 +0100
+++ gcc/gimple-fold.c 2016-01-07 13:01:25.793695288 +0100
@@ -3270,7 +3270,7 @@ gimple_fold_call (gimple_stmt_iterator *
/* Return true whether NAME has a use on STMT. */
-static bool
+bool
has_use_on_stmt (tree name, gimple *stmt)
{
imm_use_iterator iter;
--- gcc/testsuite/gcc.dg/pr69167.c.jj 2016-01-07 12:58:40.706002201 +0100
+++ gcc/testsuite/gcc.dg/pr69167.c 2016-01-07 12:58:22.000000000 +0100
@@ -0,0 +1,21 @@
+/* PR tree-optimization/69167 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+int sigsetjmp (char *);
+void foo ();
+void bar (void (*) (int *));
+extern char t[];
+
+void
+baz (int *x)
+{
+ int *a = x;
+ foo ();
+ x = 0;
+ if (sigsetjmp (t))
+ while (1)
+ bar (a ? baz : 0);
+ if (x)
+ foo ();
+}
Jakub
