Fixed type inference for COPY_TMP

Author: dstogov

ext/opcache/Optimizer/zend_inference.c

@@ -2518,7 +2518,7 @@ static zend_always_inline int _zend_update_type_info(
 					tmp |= MAY_BE_RCN;
 				}
 			}
-			if (opline->opcode != ZEND_QM_ASSIGN) {
+			if (opline->opcode == ZEND_COALESCE || opline->opcode == ZEND_JMP_SET) {
 				/* COALESCE and JMP_SET result can't be null */
 				tmp &= ~MAY_BE_NULL;
 				if (opline->opcode == ZEND_JMP_SET) {

ext/opcache/tests/jit/copy_tmp_001.phpt

@@ -0,0 +1,23 @@
+--TEST--
+JIT COPY_TMP: 001
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.file_update_protection=0
+opcache.jit_buffer_size=1M
+opcache.protect_memory=1
+--FILE--
+<?php
+function test() {
+    echo "";
+}
+
+$a = [];
+$a[test()] ??= 1;
+var_dump($a);
+?>
+--EXPECT--
+array(1) {
+  [""]=>
+  int(1)
+}