There was an embarrassing typo in the folding of BIT_NOT_EXPR for
POLY_INT_CSTs: it used - rather than ~ on the poly_int. Not sure
how that happened, but it might have been due to the way that
~x is implemented as -1 - x internally.
Tested on aarch64-linux-gnu & powerpc64le-linux-gnu (as part
of other testing). Pushed as obvious. I'll backport to all
open branches.
Richard
gcc/
PR tree-optimization/118976
* fold-const.cc (const_unop): Use ~ rather than - for BIT_NOT_EXPR.
* config/aarch64/aarch64.cc (aarch64_test_sve_folding): New function.
(aarch64_run_selftests): Run it.
---
gcc/config/aarch64/aarch64.cc | 11 +++++++++++
gcc/fold-const.cc | 2 +-
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index fe76730b0a7..af3871ce8a1 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -31336,6 +31336,16 @@ aarch64_test_sysreg_encoding_clashes (void)
}
}
+/* Test SVE arithmetic folding. */
+
+static void
+aarch64_test_sve_folding ()
+{
+ tree res = fold_unary (BIT_NOT_EXPR, ssizetype,
+ ssize_int (poly_int64 (1, 1)));
+ ASSERT_TRUE (operand_equal_p (res, ssize_int (poly_int64 (-2, -1))));
+}
+
/* Run all target-specific selftests. */
static void
@@ -31344,6 +31354,7 @@ aarch64_run_selftests (void)
aarch64_test_loading_full_dump ();
aarch64_test_fractional_cost ();
aarch64_test_sysreg_encoding_clashes ();
+ aarch64_test_sve_folding ();
}
} // namespace selftest
diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index f9f7f4d2f91..fef7a6cc48e 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -1964,7 +1964,7 @@ const_unop (enum tree_code code, tree type, tree arg0)
if (TREE_CODE (arg0) == INTEGER_CST)
return fold_not_const (arg0, type);
else if (POLY_INT_CST_P (arg0))
- return wide_int_to_tree (type, -poly_int_cst_value (arg0));
+ return wide_int_to_tree (type, ~poly_int_cst_value (arg0));
/* Perform BIT_NOT_EXPR on each element individually. */
else if (TREE_CODE (arg0) == VECTOR_CST)
{
--
2.25.1
