Hi!
The following patch fixes an ICE where one of the range tests
is SSA_NAME_DEF_STMT of a bool/_Bool or unsigned : 1 bitfield.
In that case, we don't know where to put the adjusted range test.
The patch for this uncommon case gives up, unless the range test
can be the SSA_NAME_DEF_STMT itself, and in that case makes sure we
DTRT.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2016-02-15 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/69802
* tree-ssa-reassoc.c (update_range_test): If op is
SSA_NAME_IS_DEFAULT_DEF, give up unless tem is a positive
op == 1 test of precision 1 integral op, otherwise handle
that case as op itself. Fix up formatting.
(optimize_range_tests_to_bit_test, optimize_range_tests): Fix
up formatting.
* gcc.dg/pr69802.c: New test.
--- gcc/tree-ssa-reassoc.c.jj 2016-02-12 10:23:51.000000000 +0100
+++ gcc/tree-ssa-reassoc.c 2016-02-15 14:25:54.996572238 +0100
@@ -2046,19 +2046,41 @@ update_range_test (struct range_entry *r
{
operand_entry *oe = (*ops)[range->idx];
tree op = oe->op;
- gimple *stmt = op ? SSA_NAME_DEF_STMT (op) :
- last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
+ gimple *stmt = op ? SSA_NAME_DEF_STMT (op)
+ : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
location_t loc = gimple_location (stmt);
tree optype = op ? TREE_TYPE (op) : boolean_type_node;
tree tem = build_range_check (loc, optype, unshare_expr (exp),
in_p, low, high);
enum warn_strict_overflow_code wc = WARN_STRICT_OVERFLOW_COMPARISON;
gimple_stmt_iterator gsi;
- unsigned int i;
+ unsigned int i, uid;
if (tem == NULL_TREE)
return false;
+ /* If op is default def SSA_NAME, there is no place to insert the
+ new comparison. Give up, unless we can use OP itself as the
+ range test. */
+ if (op && SSA_NAME_IS_DEFAULT_DEF (op))
+ {
+ if (op == range->exp
+ && ((TYPE_PRECISION (optype) == 1 && TYPE_UNSIGNED (optype))
+ || TREE_CODE (optype) == BOOLEAN_TYPE)
+ && (op == tem
+ || (TREE_CODE (tem) == EQ_EXPR
+ && TREE_OPERAND (tem, 0) == op
+ && integer_onep (TREE_OPERAND (tem, 1))))
+ && opcode != BIT_IOR_EXPR
+ && (opcode != ERROR_MARK || oe->rank != BIT_IOR_EXPR))
+ {
+ stmt = NULL;
+ tem = op;
+ }
+ else
+ return false;
+ }
+
if (strict_overflow_p && issue_strict_overflow_warning (wc))
warning_at (loc, OPT_Wstrict_overflow,
"assuming signed overflow does not occur "
@@ -2096,12 +2118,22 @@ update_range_test (struct range_entry *r
tem = invert_truthvalue_loc (loc, tem);
tem = fold_convert_loc (loc, optype, tem);
- gsi = gsi_for_stmt (stmt);
- unsigned int uid = gimple_uid (stmt);
+ if (stmt)
+ {
+ gsi = gsi_for_stmt (stmt);
+ uid = gimple_uid (stmt);
+ }
+ else
+ {
+ gsi = gsi_none ();
+ uid = 0;
+ }
+ if (stmt == NULL)
+ gcc_checking_assert (tem == op);
/* In rare cases range->exp can be equal to lhs of stmt.
In that case we have to insert after the stmt rather then before
it. If stmt is a PHI, insert it at the start of the basic block. */
- if (op != range->exp)
+ else if (op != range->exp)
{
gsi_insert_seq_before (&gsi, seq, GSI_SAME_STMT);
tem = force_gimple_operand_gsi (&gsi, tem, true, NULL_TREE, true,
@@ -2489,7 +2521,7 @@ optimize_range_tests_to_bit_test (enum t
operand_entry *oe = (*ops)[ranges[i].idx];
tree op = oe->op;
gimple *stmt = op ? SSA_NAME_DEF_STMT (op)
- : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
+ : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
location_t loc = gimple_location (stmt);
tree optype = op ? TREE_TYPE (op) : boolean_type_node;
@@ -2553,7 +2585,7 @@ optimize_range_tests_to_bit_test (enum t
gcc_assert (TREE_CODE (exp) == SSA_NAME);
gimple_set_visited (SSA_NAME_DEF_STMT (exp), true);
gimple *g = gimple_build_assign (make_ssa_name (optype),
- BIT_IOR_EXPR, tem, exp);
+ BIT_IOR_EXPR, tem, exp);
gimple_set_location (g, loc);
gimple_seq_add_stmt_without_update (&seq, g);
exp = gimple_assign_lhs (g);
@@ -2599,8 +2631,9 @@ optimize_range_tests (enum tree_code opc
oe = (*ops)[i];
ranges[i].idx = i;
init_range_entry (ranges + i, oe->op,
- oe->op ? NULL :
- last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id)));
+ oe->op
+ ? NULL
+ : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id)));
/* For | invert it now, we will invert it again before emitting
the optimized expression. */
if (opcode == BIT_IOR_EXPR
--- gcc/testsuite/gcc.dg/pr69802.c.jj 2016-02-15 14:06:22.716491146 +0100
+++ gcc/testsuite/gcc.dg/pr69802.c 2016-02-15 14:05:58.000000000 +0100
@@ -0,0 +1,23 @@
+/* PR tree-optimization/69802 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wall" } */
+
+struct S { unsigned f : 1; };
+int a, d;
+
+int
+foo (void)
+{
+ unsigned b = 0;
+ struct S c;
+ d = ((1 && b) < c.f) & c.f; /* { dg-warning "is used uninitialized" } */
+ return a;
+}
+
+int
+bar (_Bool c)
+{
+ unsigned b = 0;
+ d = ((1 && b) < c) & c;
+ return a;
+}
Jakub
