[PATCH v2 3/6] wcsmbs: Use loop_unroll on wcschr
Adhemerval Zanella
adhemerval.zanella@linaro.org
Wed Mar 13 14:03:00 GMT 2019
This allows an architecture to set explicit loop unrolling.
Checked on aarch64-linux-gnu.
* wcsmbs/wcschr.c (WCSCHR): Use loop_unroll.h to parametrize
the loop unroll.
---
wcsmbs/wcschr.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/wcsmbs/wcschr.c b/wcsmbs/wcschr.c
index cd66b2a58c..9de302298d 100644
--- a/wcsmbs/wcschr.c
+++ b/wcsmbs/wcschr.c
@@ -16,6 +16,7 @@
<http://www.gnu.org/licenses/>. */
#include <wchar.h>
+#include <loop_unroll.h>
#ifndef WCSCHR
# define WCSCHR __wcschr
@@ -25,12 +26,23 @@
wchar_t *
WCSCHR (const wchar_t *wcs, const wchar_t wc)
{
- do
- if (*wcs == wc)
- return (wchar_t *) wcs;
- while (*wcs++ != L'\0');
+ wchar_t *dest = NULL;
- return NULL;
+#define ITERATION(index) \
+ ({ \
+ if (*wcs == wc) \
+ dest = (wchar_t*) wcs; \
+ dest == NULL && *wcs++ != L'\0'; \
+ })
+
+#ifndef UNROLL_NTIMES
+# define UNROLL_NTIMES 1
+#endif
+
+ while (1)
+ UNROLL_REPEAT(UNROLL_NTIMES, ITERATION);
+
+ return dest;
}
libc_hidden_def (__wcschr)
weak_alias (__wcschr, wcschr)
--
2.17.1
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