JIT SSE2 optimization improvement.

git-svn-id: svn://vcs.exim.org/pcre2/code/trunk@810 6239d852-aaf2-0410-a92c-79f79f948069

1 files changed, 21 insertions, 13 deletions

diff --git a/src/pcre2_jit_compile.c b/src/pcre2_jit_compile.c
index fbbc47a..7f9a714 100644
--- a/src/pcre2_jit_compile.c
+++ b/src/pcre2_jit_compile.c
@@ -4839,7 +4839,7 @@ if (common->match_end_ptr != 0)
 
 static BOOL check_fast_forward_char_pair_sse2(compiler_common *common, fast_forward_char_data *chars, int max)
 {
-sljit_s32 i, priority, left, count;
+sljit_s32 i, j, priority, count;
 sljit_u32 priorities;
 PCRE2_UCHAR a1, a2, b1, b2;
 
@@ -4865,25 +4865,33 @@ for (priority = 7; priority > 2; priority--)
   if ((priorities & (1 << priority)) == 0)
     continue;
 
-  left = -1;
-
-  for (i = 0; i < max; i++)
+  for (i = max - 1; i >= 1; i--)
     if (chars[i].last_count >= priority)
       {
       SLJIT_ASSERT(chars[i].count <= 2 && chars[i].count >= 1);
 
-      b1 = chars[i].chars[0];
-      b2 = chars[i].chars[1];
+      a1 = chars[i].chars[0];
+      a2 = chars[i].chars[1];
+
+      j = i - max_fast_forward_char_pair_sse2_offset();
+      if (j < 0)
+        j = 0;
 
-      if (left >= 0 && i - left <= max_fast_forward_char_pair_sse2_offset() && a1 != b1 && a1 != b2 && a2 != b1 && a2 != b2)
+      while (j < i)
         {
-        fast_forward_char_pair_sse2(common, i, b1, b2, left, a1, a2);
-        return TRUE;
-        }
+        if (chars[j].last_count >= priority)
+          {
+          b1 = chars[j].chars[0];
+          b2 = chars[j].chars[1];
 
-      left = i;
-      a1 = b1;
-      a2 = b2;
+          if (a1 != b1 && a1 != b2 && a2 != b1 && a2 != b2)
+            {
+            fast_forward_char_pair_sse2(common, i, a1, a2, j, b1, b2);
+            return TRUE;
+            }
+          }
+        j++;
+        }
       }
   }