When compiling an optabs.ii at -O2 with a release-checking build,
there were 210,172 calls to fold_view_convert_expr. 99.8% of them
were conversions of an INTEGER_CST to an ENUMERAL_TYPE, so this patch
adds a fast(er) path for that case.
Tested on aarch64-linux-gnu and x86_64-linux-gnu. OK to install?
Richard
gcc/
* fold-const.c (fold_view_convert_expr): Add a fast path for
conversions of INTEGER_CSTs to other integral types.
---
gcc/fold-const.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 0b9a42f764a..19613015ddb 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -9128,6 +9128,13 @@ fold_view_convert_vector_encoding (tree type, tree expr)
static tree
fold_view_convert_expr (tree type, tree expr)
{
+ /* Conversions of INTEGER_CSTs to ENUMERAL_TYPEs are very common,
+ so handle them directly. */
+ if (INTEGRAL_TYPE_P (type)
+ && TREE_CODE (expr) == INTEGER_CST
+ && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr)))
+ return wide_int_to_tree (type, wi::to_wide (expr));
+
/* We support up to 512-bit values (for V8DFmode). */
unsigned char buffer[64];
int len;
--
2.31.1
