Add ZEND_VM_KIND_AS_STRING constant

The tool that generates the opcodes and executor (zend_vm_gen) internally uses
the ZEND_VM_KIND constant, so unless we want to change that, I went for
ZEND_VM_KIND_AS_STRING as name instead.

Author: derickr

Zend/zend_constants.stub.php

@@ -121,6 +121,12 @@
  */
 const ZEND_DEBUG_BUILD = UNKNOWN;
 
+/**
+ * @var string
+ * @cvalue ZEND_VM_KIND_AS_STRING
+ */
+const ZEND_VM_KIND_AS_STRING = UNKNOWN;
+
 /* Special constants true/false/null.  */
 
 /**

Zend/zend_constants_arginfo.h

@@ -2473,6 +2473,7 @@ function gen_vm_opcodes_header(
     $str .= "#define ZEND_VM_KIND_GOTO\t" . ZEND_VM_KIND_GOTO . "\n";
     $str .= "#define ZEND_VM_KIND_HYBRID\t" . ZEND_VM_KIND_HYBRID . "\n";
     $str .= "#define ZEND_VM_KIND_TAILCALL\t" . ZEND_VM_KIND_TAILCALL . "\n";
+    $str .= "#define ZEND_VM_KIND_AS_STRING\t\"" . $GLOBALS["vm_kind_name"][ZEND_VM_KIND] . "\"\n";
     $str .= "#if 0\n";
     if ($GLOBALS["vm_kind_name"][ZEND_VM_KIND] === "ZEND_VM_KIND_HYBRID") {
         $str .= "/* HYBRID requires support for computed GOTO and global register variables*/\n";