utf8.c: Move test out of loops

We set the upper limit of the loops before entering them to the min of
the two possible limits, thus avoiding a test each time through

diff --git a/utf8.c b/utf8.c
index 61c6c23..b4b67b6 100644 (file)
--- a/utf8.c
+++ b/utf8.c
@@ -2884,7 +2884,7 @@ S_swash_get(pTHX_ SV* swash, UV start, UV span)
     l = (U8*)SvPV(*listsvp, lcur);
     lend = l + lcur;
     while (l < lend) {
-       UV min, max, val;
+       UV min, max, val, upper;
        l = S_swash_scan_list_line(aTHX_ l, lend, &min, &max, &val,
                                         cBOOL(octets), typestr);
        if (l > lend) {
@@ -2895,6 +2895,15 @@ S_swash_get(pTHX_ SV* swash, UV start, UV span)
        if (max < start)
            continue;
 
+       /* <end> is generally 1 beyond where we want to set things, but at the
+        * platform's infinity, where we can't go any higher, we want to
+        * include the code point at <end> */
+        upper = (max < end)
+                ? max
+                : (max != UV_MAX || end != UV_MAX)
+                  ? end - 1
+                  : end;
+
        if (octets) {
            UV key;
            if (min < start) {
@@ -2903,14 +2912,8 @@ S_swash_get(pTHX_ SV* swash, UV start, UV span)
                }
                min = start;
            }
-           for (key = min; key <= max; key++) {
+           for (key = min; key <= upper; key++) {
                STRLEN offset;
-               if (key >= end)
-                   goto go_out_list;
-               /* XXX If it should ever happen (very unlikely) that we would
-                * want a non-binary result for the code point at UV_MAX,
-                * special handling would need to be inserted here, as is done
-                * below for the binary case */
                /* offset must be non-negative (start <= min <= key < end) */
                offset = octets * (key - start);
                if (bits == 8)
@@ -2935,23 +2938,12 @@ S_swash_get(pTHX_ SV* swash, UV start, UV span)
            if (min < start)
                min = start;
 
-            /* Special case when the upper-end is the highest possible code
-             * point representable on the platform.  Otherwise, the code below
-             * exits before setting this bit.  Done here to avoid testing for
-             * this extremely unlikely possibility in the loop */
-           if (UNLIKELY(end == UV_MAX && max == UV_MAX)) {
-               const STRLEN offset = (STRLEN)(max - start);
-               s[offset >> 3] |= 1 << (offset & 7);
-           }
-           for (key = min; key <= max; key++) {
+           for (key = min; key <= upper; key++) {
                const STRLEN offset = (STRLEN)(key - start);
-               if (key >= end)
-                   goto go_out_list;
                s[offset >> 3] |= 1 << (offset & 7);
            }
        }
     } /* while */
-  go_out_list:
 
     /* Invert if the data says it should be.  Assumes that bits == 1 */
     if (invert_it_svp && SvUV(*invert_it_svp)) {