Changeset 102245 in vbox

Timestamp:

Nov 22, 2023 10:43:09 AM (12 months ago)

Author:

vboxsync

Message:

libs/xpcom: Make PR_CeilingLog2() and PR_FloorLog2() inline, bugref:10545

Location:

trunk/src/libs/xpcom18a4

Files:

• Makefile.kmk (modified) (1 diff)
• nsprpub/pr/include/prbit.h (modified) (2 diffs)
• nsprpub/pr/src/misc/prlog2.c (deleted)

trunk/src/libs/xpcom18a4/Makefile.kmk

@@ -429 +429 @@
         nsprpub/pr/src/io/prprf.c \
         nsprpub/pr/src/misc/prinrval.c \
-        nsprpub/pr/src/misc/prlog2.c \
         nsprpub/pr/src/misc/prlong.c \
         nsprpub/lib/ds/plarena.c \

trunk/src/libs/xpcom18a4/nsprpub/pr/include/prbit.h

@@ -39 +39 @@
 #define prbit_h___
 
+#include <iprt/cdefs.h>
+
 #include "prtypes.h"
-
-#ifdef VBOX_WITH_XPCOM_NAMESPACE_CLEANUP
-#define PR_CeilingLog2 VBoxNsprPR_CeilingLog2
-#define PR_FloorLog2 VBoxNsprPR_FloorLog2
-#endif /* VBOX_WITH_XPCOM_NAMESPACE_CLEANUP */
 
 PR_BEGIN_EXTERN_C
@@ -63 +60 @@
 ** Compute the log of the least power of 2 greater than or equal to n
 */
-NSPR_API(PRIntn) PR_CeilingLog2(PRUint32 i); 
+DECL_FORCE_INLINE(PRIntn) PR_CeilingLog2(PRUint32 n)
+{
+    PRIntn log2 = 0;
+
+    if (n & (n-1))
+  log2++;
+    if (n >> 16)
+  log2 += 16, n >>= 16;
+    if (n >> 8)
+  log2 += 8, n >>= 8;
+    if (n >> 4)
+  log2 += 4, n >>= 4;
+    if (n >> 2)
+  log2 += 2, n >>= 2;
+    if (n >> 1)
+  log2++;
+    return log2;
+}
 
 /*
-** Compute the log of the greatest power of 2 less than or equal to n
+** Compute the log of the greatest power of 2 less than or equal to n.
+** This really just finds the highest set bit in the word.
 */
-NSPR_API(PRIntn) PR_FloorLog2(PRUint32 i); 
+DECL_FORCE_INLINE(PRIntn) PR_FloorLog2(PRUint32 n)
+{
+    PRIntn log2 = 0;
+
+    if (n >> 16)
+  log2 += 16, n >>= 16;
+    if (n >> 8)
+  log2 += 8, n >>= 8;
+    if (n >> 4)
+  log2 += 4, n >>= 4;
+    if (n >> 2)
+  log2 += 2, n >>= 2;
+    if (n >> 1)
+  log2++;
+    return log2;
+}
 
 /*