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[PATCH] Workaround for ffs() on LP64 targets
- From: Sebastian Huber <sebastian dot huber at embedded-brains dot de>
- To: newlib at sourceware dot org
- Date: Thu, 27 Jul 2017 10:06:24 +0200
- Subject: [PATCH] Workaround for ffs() on LP64 targets
- Authentication-results: sourceware.org; auth=none
Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
---
newlib/libc/misc/ffs.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/newlib/libc/misc/ffs.c b/newlib/libc/misc/ffs.c
index ba5700920..a09cbd3bb 100644
--- a/newlib/libc/misc/ffs.c
+++ b/newlib/libc/misc/ffs.c
@@ -31,6 +31,17 @@ No supporting OS subroutines are required. */
int
ffs(int i)
{
+#ifdef __LP64__
+ /* GCC would expand the __builtin_ffs() to ffs() in this case */
+ int bit;
+
+ if (i == 0)
+ return (0);
+ for (bit = 1; !(i & 1); bit++)
+ i = (unsigned int)i >> 1;
+ return (bit);
+#else
return (__builtin_ffs(i));
+#endif
}
--
2.12.3