Allow inferring narrowed return type

Even if an explicit return type is given, we might still infer
a more narrow one based on return statements. We shouldn't
pessimize this just because a type has been declared.

1 files changed, 44 insertions, 0 deletions

diff --git a/ext/opcache/tests/opt/verify_return_type.phpt b/ext/opcache/tests/opt/verify_return_type.phpt
new file mode 100644
index 0000000000..c1384c7af8
--- /dev/null
+++ b/ext/opcache/tests/opt/verify_return_type.phpt
@@ -0,0 +1,44 @@
+--TEST--
+Return type check elision
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.opt_debug_level=0x20000
+opcache.preload=
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+
+class Test1 {
+    final public function getIntOrFloat(int $i): int|float {
+        return $i;
+    }
+    final public function getInt(): int {
+        return $this->getIntOrFloat();
+    }
+}
+
+?>
+--EXPECTF--
+$_main:
+     ; (lines=1, args=0, vars=0, tmps=0)
+     ; (after optimizer)
+     ; %s
+0000 RETURN int(1)
+
+Test1::getIntOrFloat:
+     ; (lines=2, args=1, vars=1, tmps=0)
+     ; (after optimizer)
+     ; %s
+0000 CV0($i) = RECV 1
+0001 RETURN CV0($i)
+
+Test1::getInt:
+     ; (lines=3, args=0, vars=0, tmps=1)
+     ; (after optimizer)
+     ; %s
+0000 INIT_METHOD_CALL 0 THIS string("getIntOrFloat")
+0001 V0 = DO_UCALL
+0002 RETURN V0