PoC

Zend/Optimizer/zend_optimizer.c

@@ -1526,52 +1526,9 @@ static bool needs_live_range(const zend_op_array *op_array, const zend_op *def_o
 	return (type & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_REF)) != 0;
 }
 
-static void zend_foreach_op_array_helper(
-		zend_op_array *op_array, zend_op_array_func_t func, void *context) {
-	func(op_array, context);
-	for (uint32_t i = 0; i < op_array->num_dynamic_func_defs; i++) {
-		zend_foreach_op_array_helper(op_array->dynamic_func_defs[i], func, context);
-	}
-}
-
 void zend_foreach_op_array(zend_script *script, zend_op_array_func_t func, void *context)
 {
-	zval *zv;
-	zend_op_array *op_array;
-
-	zend_foreach_op_array_helper(&script->main_op_array, func, context);
-
-	ZEND_HASH_MAP_FOREACH_PTR(&script->function_table, op_array) {
-		zend_foreach_op_array_helper(op_array, func, context);
-	} ZEND_HASH_FOREACH_END();
-
-	ZEND_HASH_MAP_FOREACH_VAL(&script->class_table, zv) {
-		if (Z_TYPE_P(zv) == IS_ALIAS_PTR) {
-			continue;
-		}
-		const zend_class_entry *ce = Z_CE_P(zv);
-		ZEND_HASH_MAP_FOREACH_PTR(&ce->function_table, op_array) {
-			if (op_array->scope == ce
-					&& op_array->type == ZEND_USER_FUNCTION
-					&& !(op_array->fn_flags & ZEND_ACC_ABSTRACT)
-					&& !(op_array->fn_flags & ZEND_ACC_TRAIT_CLONE)) {
-				zend_foreach_op_array_helper(op_array, func, context);
-			}
-		} ZEND_HASH_FOREACH_END();
-
-		zend_property_info *property;
-		ZEND_HASH_MAP_FOREACH_PTR(&ce->properties_info, property) {
-			zend_function **hooks = property->hooks;
-			if (property->ce == ce && property->hooks) {
-				for (uint32_t i = 0; i < ZEND_PROPERTY_HOOK_COUNT; i++) {
-					const zend_function *hook = hooks[i];
-					if (hook && hook->common.scope == ce && !(hooks[i]->op_array.fn_flags & ZEND_ACC_TRAIT_CLONE)) {
-						zend_foreach_op_array_helper(&hooks[i]->op_array, func, context);
-					}
-				}
-			}
-		} ZEND_HASH_FOREACH_END();
-	} ZEND_HASH_FOREACH_END();
+	zend_foreach_op_array_ex(&script->main_op_array, &script->function_table, &script->class_table, func, context);
 }
 
 static void step_optimize_op_array(zend_op_array *op_array, void *context) {

Zend/tests/first_class_callable/constexpr/namespace_004.phpt

@@ -1,5 +1,11 @@
 --TEST--
 Allow defining FCC in const expressions in a namespace with function matching a global function later.
+--SKIPIF--
+<?php
+if (function_exists('opcache_get_status')) {
+    die('skip not for opcache');
+}
+?>
 --FILE--
 <?php
 

Zend/tests/ns_global_func_assumption_001.phpt

@@ -0,0 +1,17 @@
+--TEST--
+NS global function assumption: basic optimization
+--FILE--
+<?php
+
+namespace Ns {
+    function test() {
+        // Unqualified strlen() should be compiled as a direct call to \strlen()
+        return strlen("hello");
+    }
+}
+
+namespace {
+    var_dump(Ns\test());
+}
+--EXPECT--
+int(5)

Zend/tests/ns_global_func_assumption_002.inc

@@ -0,0 +1,8 @@
+<?php
+
+namespace Ns {
+    function test() {
+        // Unqualified strlen() should be compiled as \strlen() initially
+        return strlen("hello");
+    }
+}

Zend/tests/ns_global_func_assumption_002.phpt

@@ -0,0 +1,22 @@
+--TEST--
+NS global function assumption: deoptimization when shadow is declared at runtime
+--FILE--
+<?php
+
+// Include a file with Ns\test() that calls strlen() unqualified.
+// It should be compiled assuming strlen() resolves to \strlen().
+include __DIR__ . '/ns_global_func_assumption_002.inc';
+
+// First call: no shadow exists, uses global strlen() (constant-folded).
+var_dump(Ns\test());
+
+// Now declare Ns\strlen() which shadows the global strlen().
+include __DIR__ . '/ns_global_func_assumption_002_shadow.inc';
+
+// Second call: Ns\test() should be deoptimized and use Ns\strlen().
+var_dump(Ns\test());
+
+?>
+--EXPECT--
+int(5)
+string(8) "shadow:5"

Zend/tests/ns_global_func_assumption_002_shadow.inc

@@ -0,0 +1,7 @@
+<?php
+
+namespace Ns {
+    function strlen(string $str): string {
+        return "shadow:" . \strlen($str);
+    }
+}

Zend/zend_API.c

@@ -3042,6 +3042,7 @@ ZEND_API zend_result zend_register_functions(zend_class_entry *scope, const zend
 		internal_function->function_name = zend_string_init_interned(ptr->fname, fname_len, 1);
 		internal_function->scope = scope;
 		internal_function->prototype = NULL;
+		internal_function->fn_flags2 = 0;
 		internal_function->prop_info = NULL;
 		internal_function->attributes = NULL;
 		internal_function->frameless_function_infos = ptr->frameless_function_infos;

Zend/zend_bitset.h

@@ -296,4 +296,14 @@ static inline int zend_bitset_pop_first(zend_bitset set, uint32_t len) {
 	return i;
 }
 
+static inline bool zend_bitset_has_intersection(zend_bitset set1, zend_bitset set2, uint32_t len)
+{
+	for (uint32_t i = 0; i < len; i++) {
+		if (set1[i] & set2[i]) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
 #endif /* _ZEND_BITSET_H_ */