Fix phpGH-11956: PCRE regular expressions with JIT enabled gives different result

The code in the attached test used to work correctly in PHP 8.0, but not
in 8.1+. This is because PHP 8.1+ uses a more modern version of pcre2
than PHP 8.0, and that pcre2 versions has a regression.

While upgrading pcre2lib seems to be only done for the master branch, it
is possible to backport upstream fixes to stable branches. This has been
already done in the past in for JIT regressions [1], so it is not
unprecedented.

We backport the upstream pcre2 fix [2].

[1] php@788a701e222
[2] PCRE2Project/pcre2#135

Author: nielsdos

ext/pcre/pcre2lib/pcre2_jit_compile.c

@@ -11286,19 +11286,19 @@ if (exact > 1)
     }
   }
 else if (exact == 1)
-  {
   compile_char1_matchingpath(common, type, cc, &backtrack->topbacktracks, TRUE);
 
-  if (early_fail_type == type_fail_range)
-    {
-    OP1(SLJIT_MOV, TMP1, 0, SLJIT_MEM1(SLJIT_SP), early_fail_ptr);
-    OP1(SLJIT_MOV, TMP2, 0, SLJIT_MEM1(SLJIT_SP), early_fail_ptr + (int)sizeof(sljit_sw));
-    OP2(SLJIT_SUB, TMP1, 0, TMP1, 0, TMP2, 0);
-    OP2(SLJIT_SUB, TMP2, 0, STR_PTR, 0, TMP2, 0);
-    add_jump(compiler, &backtrack->topbacktracks, CMP(SLJIT_LESS_EQUAL, TMP2, 0, TMP1, 0));
+if (early_fail_type == type_fail_range)
+  {
+  /* Range end first, followed by range start. */
+  OP1(SLJIT_MOV, TMP1, 0, SLJIT_MEM1(SLJIT_SP), early_fail_ptr);
+  OP1(SLJIT_MOV, TMP2, 0, SLJIT_MEM1(SLJIT_SP), early_fail_ptr + (int)sizeof(sljit_sw));
+  OP2(SLJIT_SUB, TMP1, 0, TMP1, 0, TMP2, 0);
+  OP2(SLJIT_SUB, TMP2, 0, STR_PTR, 0, TMP2, 0);
+  add_jump(compiler, &backtrack->topbacktracks, CMP(SLJIT_LESS_EQUAL, TMP2, 0, TMP1, 0));
 
-    OP1(SLJIT_MOV, SLJIT_MEM1(SLJIT_SP), early_fail_ptr + (int)sizeof(sljit_sw), STR_PTR, 0);
-    }
+  OP1(SLJIT_MOV, SLJIT_MEM1(SLJIT_SP), early_fail_ptr, STR_PTR, 0);
+  OP1(SLJIT_MOV, SLJIT_MEM1(SLJIT_SP), early_fail_ptr + (int)sizeof(sljit_sw), STR_PTR, 0);
   }
 
 switch(opcode)

ext/pcre/tests/gh11956.phpt

@@ -0,0 +1,16 @@
+--TEST--
+GH-11956 (PCRE regular expressions with JIT enabled gives different result)
+--INI--
+pcre.jit=1
+--FILE--
+<?php
+preg_match( '/<(\w+)[\s\w\-]+ id="S44_i89ew">/', '<br><div id="S44_i89ew">', $matches );
+var_dump($matches);
+?>
+--EXPECT--
+array(2) {
+  [0]=>
+  string(20) "<div id="S44_i89ew">"
+  [1]=>
+  string(2) "di"
+}