Add intadd function

Author: adsr

ext/standard/basic_functions.stub.php

@@ -3002,6 +3002,9 @@ function is_nan(float $num): bool {}
 /** @compile-time-eval */
 function intdiv(int $num1, int $num2): int {}
 
+/** @compile-time-eval */
+function intadd(int $num1, int $num2): int {}
+
 /** @compile-time-eval */
 function is_infinite(float $num): bool {}
 

ext/standard/basic_functions_arginfo.h

@@ -1215,3 +1215,17 @@ PHP_FUNCTION(intdiv)
 	RETURN_LONG(dividend / divisor);
 }
 /* }}} */
+
+/* {{{ Returns sum of integers, allowing overflow */
+PHP_FUNCTION(intadd)
+{
+	zend_long addend1, addend2;
+
+	ZEND_PARSE_PARAMETERS_START(2, 2)
+		Z_PARAM_LONG(addend1)
+		Z_PARAM_LONG(addend2)
+	ZEND_PARSE_PARAMETERS_END();
+
+	RETURN_LONG(addend1 + addend2);
+}
+/* }}} */

ext/standard/math.c

@@ -0,0 +1,14 @@
+--TEST--
+intadd functionality
+--FILE--
+<?php
+var_dump(intadd(41, 1)           === 42);
+var_dump(intadd(-1, 1)           === 0);
+var_dump(intadd(PHP_INT_MAX,  1) === PHP_INT_MIN);
+var_dump(intadd(PHP_INT_MIN, -1) === PHP_INT_MAX);
+?>
+--EXPECT--
+bool(true)
+bool(true)
+bool(true)
+bool(true)