toplev.c (floor_log2): Rename from floor_log2_wide, use CLZ_HWI.

        * toplev.c (floor_log2): Rename from floor_log2_wide, use CLZ_HWI.
        (exact_log2): Rename from exact_log2_wide, use CTZ_HWI.
        * toplev.h (FL2T__): Remove.
        (CLZ_HWI): Rename from FL2T_CLZ__.
        (CTZ_HWI): New.
        (floor_log2): Simplify.
        (exact_log2): New.

From-SVN: r90519

1 files changed, 20 insertions, 14 deletions

diff --git a/gcc/toplev.c b/gcc/toplev.c
index afc43f8..4ce593a 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -537,20 +537,23 @@ read_integral_parameter (const char *p, const char *pname, const int  defval)
 }
 
 /* Given X, an unsigned number, return the largest int Y such that 2**Y <= X.
-   If X is 0, return -1.
-
-   This should be used via the floor_log2 macro.  */
+   If X is 0, return -1.  */
 
 int
-floor_log2_wide (unsigned HOST_WIDE_INT x)
+floor_log2 (unsigned HOST_WIDE_INT x)
 {
-  int t=0;
+  int t = 0;
+
   if (x == 0)
     return -1;
-  if (sizeof (HOST_WIDE_INT) * 8 > 64)
+
+#ifdef CLZ_HWI
+  t = HOST_BITS_PER_WIDE_INT - 1 - (int) CLZ_HWI (x);
+#else
+  if (HOST_BITS_PER_WIDE_INT > 64)
     if (x >= (unsigned HOST_WIDE_INT) 1 << (t + 64))
       t += 64;
-  if (sizeof (HOST_WIDE_INT) * 8 > 32)
+  if (HOST_BITS_PER_WIDE_INT > 32)
     if (x >= ((unsigned HOST_WIDE_INT) 1) << (t + 32))
       t += 32;
   if (x >= ((unsigned HOST_WIDE_INT) 1) << (t + 16))
@@ -563,21 +566,24 @@ floor_log2_wide (unsigned HOST_WIDE_INT x)
     t += 2;
   if (x >= ((unsigned HOST_WIDE_INT) 1) << (t + 1))
     t += 1;
+#endif
+
   return t;
 }
 
 /* Return the logarithm of X, base 2, considering X unsigned,
-   if X is a power of 2.  Otherwise, returns -1.
-
-   This should be used via the `exact_log2' macro.  */
+   if X is a power of 2.  Otherwise, returns -1.  */
 
 int
-exact_log2_wide (unsigned HOST_WIDE_INT x)
+exact_log2 (unsigned HOST_WIDE_INT x)
 {
-  /* Test for 0 or a power of 2.  */
-  if (x == 0 || x != (x & -x))
+  if (x != (x & -x))
     return -1;
-  return floor_log2_wide (x);
+#ifdef CTZ_HWI
+  return x ? CTZ_HWI (x) : -1;
+#else
+  return floor_log2 (x);
+#endif
 }
 
 /* Handler for fatal signals, such as SIGSEGV.  These are transformed