Implement new ZEND_JMP_NULL instruction

Author: iluuu1994

Zend/tests/nullsafe_method_call/011.phpt

@@ -23,14 +23,11 @@ $foo->bar = 'bar';
 var_dump(isset($foo?->bar));
 var_dump(empty($foo?->bar));
 
---EXPECTF--
-Warning: Undefined variable $foo in %s011.php on line 8
-NULL
-
-Warning: Undefined variable $foo in %s011.php on line 9
-NULL
-NULL
-NULL
+--EXPECT--
+bool(false)
+bool(true)
+bool(false)
+bool(true)
 bool(false)
 bool(true)
 bool(true)

Zend/zend_compile.c

@@ -64,7 +64,7 @@ typedef struct _zend_loop_var {
 
 typedef struct _zend_short_circuiting_scope {
 	zend_stack jump_opnums;
-	zend_bool skip;
+	zend_bool flags;
 } zend_short_circuiting_scope;
 
 static inline uint32_t zend_alloc_cache_slots(unsigned count) {
@@ -2177,6 +2177,7 @@ static inline void zend_update_jump_target(uint32_t opnum_jump, uint32_t opnum_t
 		case ZEND_JMPNZ_EX:
 		case ZEND_JMP_SET:
 		case ZEND_COALESCE:
+		case ZEND_JMP_NULL:
 			opline->op2.opline_num = opnum_target;
 			break;
 		EMPTY_SWITCH_DEFAULT_CASE()
@@ -2249,7 +2250,7 @@ static void zend_begin_short_circuiting_scope()
 
 	zend_short_circuiting_scope scope;
 	zend_stack_init(&scope.jump_opnums, sizeof(uint32_t));
-	scope.skip = 0;
+	scope.flags = 0;
 	zend_stack_push(&CG(short_circuiting_scopes), &scope);
 }
 
@@ -2269,11 +2270,18 @@ static void zend_end_short_circuiting_scope(znode *result)
 			zend_stack_del_top(labels);
 		}
 
-		znode null_node;
-		null_node.op_type = IS_CONST;
-		ZVAL_NULL(&null_node.u.constant);
+		znode result_node;
+		result_node.op_type = IS_CONST;
 
-		zend_op *opline_call = zend_emit_op_tmp(NULL, ZEND_QM_ASSIGN, &null_node, NULL);
+		if (scope->flags & ZEND_SHORT_CIRCUITING_SCOPE_ISSET) {
+			ZVAL_BOOL(&result_node.u.constant, 0);
+		} else if (scope->flags & ZEND_SHORT_CIRCUITING_SCOPE_EMPTY) {
+			ZVAL_BOOL(&result_node.u.constant, 1);
+		} else {
+			ZVAL_NULL(&result_node.u.constant);
+		}
+
+		zend_op *opline_call = zend_emit_op_tmp(NULL, ZEND_QM_ASSIGN, &result_node, NULL);
 		SET_NODE(opline_call->result, result);
 
 		zend_update_jump_target_to_next(end_label);
@@ -2767,17 +2775,11 @@ static zend_op *zend_delayed_compile_prop(znode *result, zend_ast *ast, uint32_t
 	}
 
 	if (nullsafe) {
-		znode typecheck_node;
-		zend_op *typecheck_opline = zend_emit_op_tmp(&typecheck_node, ZEND_TYPE_CHECK, &obj_node, NULL);
-		typecheck_opline->extended_value = 1 << IS_NULL;
-
-		uint32_t jmp_call = zend_emit_cond_jump(ZEND_JMPZ, &typecheck_node, 0);
+		uint32_t jmp_null = zend_emit_cond_jump(ZEND_JMP_NULL, &obj_node, 0);
 
 		zend_short_circuiting_scope *short_circuiting_scope = zend_current_short_circuiting_scope();
 		zend_stack *short_circuiting_scopes = &short_circuiting_scope->jump_opnums;
-		uint32_t jmp_end = zend_emit_jump(0);
-		zend_stack_push(short_circuiting_scopes, &jmp_end);
-		zend_update_jump_target_to_next(jmp_call);
+		zend_stack_push(short_circuiting_scopes, &jmp_null);
 	}
 
 	zend_compile_expr(&prop_node, prop_ast);
@@ -4249,17 +4251,11 @@ void zend_compile_method_call(znode *result, zend_ast *ast, uint32_t type) /* {{
 	}
 
 	if (nullsafe) {
-		znode typecheck_node;
-		zend_op *typecheck_opline = zend_emit_op_tmp(&typecheck_node, ZEND_TYPE_CHECK, &obj_node, NULL);
-		typecheck_opline->extended_value = 1 << IS_NULL;
-
-		uint32_t jmp_call = zend_emit_cond_jump(ZEND_JMPZ, &typecheck_node, 0);
+		uint32_t jmp_null = zend_emit_cond_jump(ZEND_JMP_NULL, &obj_node, 0);
 
 		zend_short_circuiting_scope *short_circuiting_scope = zend_current_short_circuiting_scope();
 		zend_stack *short_circuiting_scopes = &short_circuiting_scope->jump_opnums;
-		uint32_t jmp_end = zend_emit_jump(0);
-		zend_stack_push(short_circuiting_scopes, &jmp_end);
-		zend_update_jump_target_to_next(jmp_call);
+		zend_stack_push(short_circuiting_scopes, &jmp_null);
 	}
 
 	zend_compile_expr(&method_node, method_ast);
@@ -8260,7 +8256,9 @@ void zend_compile_isset_or_empty(znode *result, zend_ast *ast) /* {{{ */
 	ZEND_ASSERT(ast->kind == ZEND_AST_ISSET || ast->kind == ZEND_AST_EMPTY);
 
 	zend_begin_short_circuiting_scope();
-	zend_current_short_circuiting_scope()->skip = 1;
+	zend_current_short_circuiting_scope()->flags = ast->kind == ZEND_AST_ISSET
+		? ZEND_SHORT_CIRCUITING_SCOPE_ISSET
+		: ZEND_SHORT_CIRCUITING_SCOPE_EMPTY;
 
 	if (!zend_is_variable(var_ast)) {
 		if (ast->kind == ZEND_AST_EMPTY) {

Zend/zend_opcode.c

@@ -987,6 +987,7 @@ ZEND_API int pass_two(zend_op_array *op_array)
 			case ZEND_COALESCE:
 			case ZEND_FE_RESET_R:
 			case ZEND_FE_RESET_RW:
+			case ZEND_JMP_NULL:
 				ZEND_PASS_TWO_UPDATE_JMP_TARGET(op_array, opline, opline->op2);
 				break;
 			case ZEND_ASSERT_CHECK:

Zend/zend_vm_def.h

@@ -7032,6 +7032,21 @@ ZEND_VM_COLD_CONST_HANDLER(169, ZEND_COALESCE, CONST|TMP|VAR|CV, JMP_ADDR)
 	ZEND_VM_NEXT_OPCODE();
 }
 
+ZEND_VM_HOT_NOCONST_HANDLER(195, ZEND_JMP_NULL, CONST|TMP|VAR|CV, JMP_ADDR)
+{
+	USE_OPLINE
+	zval *val;
+
+	val = GET_OP1_ZVAL_PTR_UNDEF(BP_VAR_R);
+
+	if (Z_TYPE_INFO_P(val) != IS_NULL) {
+		ZEND_VM_NEXT_OPCODE();
+	} else {
+		FREE_OP1();
+		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
+	}
+}
+
 ZEND_VM_HOT_HANDLER(31, ZEND_QM_ASSIGN, CONST|TMP|VAR|CV, ANY)
 {
 	USE_OPLINE