commit b65726d0823c1e4c64a434635556c1a1fa2acb58
author William A. Rowe Jr <wrowe@apache.org> Wed Jun 08 22:13:41 2016 +0000
committer William A. Rowe Jr <wrowe@apache.org> Wed Jun 08 22:13:41 2016 +0000
tree 422e373273eb8e0017dbde654221c1a8ec11edf5
parent 4d7b7ec9879e573583ef4ba5b4a655aeb7bee934

Third optimization, use short type, which is the smallest
functional int which requires 1. no unsigned -> signed
promotion, 2. fetches from a word aligned offset from 
the lookup table, 3. is easily promoted to int upon the
function's return.  This introduces a very small 2% speed
improvement in several cases.



git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@1747460 13f79535-47bb-0310-9956-ffa450edef68

strings/apr_cstr.c

diff --git a/strings/apr_cstr.c b/strings/apr_cstr.c
index fb940c4..a79bf0f 100644
--- a/strings/apr_cstr.c
+++ b/strings/apr_cstr.c
@@ -196,7 +196,7 @@
  * octets (such as extended latin alphabetics) are never case-folded.
  * NOTE: Other than Alpha A-Z/a-z, each code point is unique!
  */
-static const unsigned char ucharmap[] = {
+static const short ucharmap[] = {
     0x0,  0x1,  0x2,  0x3,  0x4,  0x5,  0x6,  0x7,
     0x8,  0x9,  0xa,  0xb,  0xc,  0xd,  0xe,  0xf,
     0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
@@ -243,7 +243,7 @@
  *
  * NOTE: Other than Alpha A-Z/a-z, each code point is unique!
  */
-static const unsigned char ucharmap[] = {
+static const short ucharmap[] = {
     0x00, 0x01, 0x02, 0x03, 0x9C, 0x09, 0x86, 0x7F,
     0x97, 0x8D, 0x8E, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
     0x10, 0x11, 0x12, 0x13, 0x9D, 0x85, 0x08, 0x87,
@@ -283,9 +283,9 @@
 {
     for (;;)
     {
-        const int c1 = (int)(*((const unsigned char *)str1));
-        const int c2 = (int)(*((const unsigned char *)str2));
-        const int cmp = ucharmap[c1] - ucharmap[c2];
+        const short c1 = (short)(*((const unsigned char *)str1));
+        const short c2 = (short)(*((const unsigned char *)str2));
+        const short cmp = ucharmap[c1] - ucharmap[c2];
         /* Not necessary to test for !c2, this is caught by cmp */
         if (cmp || !c1)
             return cmp;
@@ -298,9 +298,9 @@
 {
     while (n--)
     {
-        const int c1 = (int)(*((const unsigned char *)str1));
-        const int c2 = (int)(*((const unsigned char *)str2));
-        const int cmp = ucharmap[c1] - ucharmap[c2];
+        const short c1 = (short)(*((const unsigned char *)str1));
+        const short c2 = (short)(*((const unsigned char *)str2));
+        const short cmp = ucharmap[c1] - ucharmap[c2];
         /* Not necessary to test for !c2, this is caught by cmp */
         if (cmp || !c1)
             return cmp;