Hi!
The following two match.pd spots assume that integer_pow2p will return
true only for INTEGER_CSTs (it uses wi::to_wide on it), but as the testcase
shows, that is not always the case, we can get there with COMPLEX_CSTs.
Fixed by requiring that it is both INTEGER_CST and integer_pow2p,
bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
I went through other spots where integer_pow2p is used in match.pd and think
all other spots should be safe, I don't think we e.g. allow BIT_AND_EXPR
with COMPLEX_CST operand etc.
2018-03-12 Jakub Jelinek <ja...@redhat.com>
PR middle-end/84834
* match.pd ((A & C) != 0 ? D : 0): Use INTEGER_CST@2 instead of
integer_pow2p@2 and test integer_pow2p in condition.
(A < 0 ? C : 0): Similarly for @1.
* gcc.dg/pr84834.c: New test.
--- gcc/match.pd.jj 2018-03-06 08:06:13.000000000 +0100
+++ gcc/match.pd 2018-03-12 19:18:24.144577077 +0100
@@ -3566,16 +3566,18 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(simplify
(cond
(ne (bit_and @0 integer_pow2p@1) integer_zerop)
- integer_pow2p@2 integer_zerop)
- (with {
- int shift = (wi::exact_log2 (wi::to_wide (@2))
- - wi::exact_log2 (wi::to_wide (@1)));
- }
- (if (shift > 0)
- (bit_and
- (lshift (convert @0) { build_int_cst (integer_type_node, shift); }) @2)
- (bit_and
- (convert (rshift @0 { build_int_cst (integer_type_node, -shift); })) @2))))
+ INTEGER_CST@2 integer_zerop)
+ (if (integer_pow2p (@2))
+ (with {
+ int shift = (wi::exact_log2 (wi::to_wide (@2))
+ - wi::exact_log2 (wi::to_wide (@1)));
+ }
+ (if (shift > 0)
+ (bit_and
+ (lshift (convert @0) { build_int_cst (integer_type_node, shift); }) @2)
+ (bit_and
+ (convert (rshift @0 { build_int_cst (integer_type_node, -shift); }))
+ @2)))))
/* If we have (A & C) != 0 where C is the sign bit of A, convert
this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
@@ -3595,8 +3597,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(simplify
(cond
(lt @0 integer_zerop)
- integer_pow2p@1 integer_zerop)
- (if (!TYPE_UNSIGNED (TREE_TYPE (@0)))
+ INTEGER_CST@1 integer_zerop)
+ (if (integer_pow2p (@1)
+ && !TYPE_UNSIGNED (TREE_TYPE (@0)))
(with {
int shift = element_precision (@0) - wi::exact_log2 (wi::to_wide (@1)) - 1;
}
--- gcc/testsuite/gcc.dg/pr84834.c.jj 2018-03-12 19:21:15.677631881 +0100
+++ gcc/testsuite/gcc.dg/pr84834.c 2018-03-12 19:20:59.105626588 +0100
@@ -0,0 +1,15 @@
+/* PR middle-end/84834 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+_Complex int
+foo (int a)
+{
+ return a < 0;
+}
+
+_Complex int
+bar (int a)
+{
+ return (a & 8) ? (_Complex int) 16 : (_Complex int) 0;
+}
Jakub
