[Qemu-devel] [PATCH] bitops: unify bitops_ffsl with the one in host-utils.h

[Paolo Bonzini]

Fixes the build on Mac OS X, which has ffsl.

Signed-off-by: Paolo Bonzini <address@hidden>
---
 include/qemu/bitops.h     | 40 ++++++++++++++--------------------------
 include/qemu/hbitmap.h    |  2 +-
 include/qemu/host-utils.h | 25 -------------------------
 util/hbitmap.c            |  2 +-
 4 files changed, 16 insertions(+), 53 deletions(-)

diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h
index 74e14e5..a59bfdc 100644
--- a/include/qemu/bitops.h
+++ b/include/qemu/bitops.h
@@ -13,6 +13,7 @@
 #define BITOPS_H
 
 #include "qemu-common.h"
+#include "host-utils.h"
 
 #define BITS_PER_BYTE           CHAR_BIT
 #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
@@ -30,34 +31,21 @@
  */
 static unsigned long bitops_ffsl(unsigned long word)
 {
-       int num = 0;
+    if (!word) {
+        return 0;
+    }
 
-#if LONG_MAX > 0x7FFFFFFF
-       if ((word & 0xffffffff) == 0) {
-               num += 32;
-               word >>= 32;
-       }
+#if QEMU_GNUC_PREREQ(3, 4)
+    return __builtin_ctzl(word) + 1;
+#else
+    if (sizeof(long) == 4) {
+        return ctz32(word) + 1;
+    } else if (sizeof(long) == 8) {
+        return ctz64(word) + 1;
+    } else {
+        abort();
+    }
 #endif
-       if ((word & 0xffff) == 0) {
-               num += 16;
-               word >>= 16;
-       }
-       if ((word & 0xff) == 0) {
-               num += 8;
-               word >>= 8;
-       }
-       if ((word & 0xf) == 0) {
-               num += 4;
-               word >>= 4;
-       }
-       if ((word & 0x3) == 0) {
-               num += 2;
-               word >>= 2;
-       }
-       if ((word & 0x1) == 0) {
-               num += 1;
-        }
-       return num;
 }
 
 /**
diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h
index 73f5d1d..abad209 100644
--- a/include/qemu/hbitmap.h
+++ b/include/qemu/hbitmap.h
@@ -170,7 +170,7 @@ static inline int64_t hbitmap_iter_next(HBitmapIter *hbi)
 
     /* The next call will resume work from the next bit.  */
     hbi->cur[HBITMAP_LEVELS - 1] = cur & (cur - 1);
-    item = ((uint64_t)hbi->pos << BITS_PER_LEVEL) + ffsl(cur) - 1;
+    item = ((uint64_t)hbi->pos << BITS_PER_LEVEL) + bitops_ffsl(cur) - 1;
 
     return item << hbi->granularity;
 }
diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h
index 2a32be4..40457bd 100644
--- a/include/qemu/host-utils.h
+++ b/include/qemu/host-utils.h
@@ -238,29 +238,4 @@ static inline int ctpop64(uint64_t val)
 #endif
 }
 
-/* glibc does not provide an inline version of ffsl, so always define
- * ours.  We need to give it a different name, however.
- */
-#ifdef __GLIBC__
-#define ffsl qemu_ffsl
-#endif
-static inline int ffsl(long val)
-{
-    if (!val) {
-        return 0;
-    }
-
-#if QEMU_GNUC_PREREQ(3, 4)
-    return __builtin_ctzl(val) + 1;
-#else
-    if (sizeof(long) == 4) {
-        return ctz32(val) + 1;
-    } else if (sizeof(long) == 8) {
-        return ctz64(val) + 1;
-    } else {
-        abort();
-    }
-#endif
-}
-
 #endif
diff --git a/util/hbitmap.c b/util/hbitmap.c
index 2aa487d..32c3d59 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -126,7 +126,7 @@ unsigned long hbitmap_iter_skip_words(HBitmapIter *hbi)
          * The index of this word's least significant set bit provides
          * the low-order bits.
          */
-        pos = (pos << BITS_PER_LEVEL) + ffsl(cur) - 1;
+        pos = (pos << BITS_PER_LEVEL) + bitops_ffsl(cur) - 1;
         hbi->cur[i] = cur & (cur - 1);
 
         /* Set up next level for iteration.  */
-- 
1.8.1