JIT: Partially fix handling of exceptions thrown in interrupt handlers

Author: dstogov

ext/opcache/jit/zend_jit_disasm_x86.c

@@ -496,6 +496,7 @@ static int zend_jit_disasm_init(void)
 	REGISTER_HELPER(zval_jit_update_constant_ex);
 #endif
 	REGISTER_HELPER(zend_jit_free_trampoline_helper);
+	REGISTER_HELPER(zend_jit_exception_in_interrupt_handler_helper);
 #undef  REGISTER_HELPER
 
 #ifndef _WIN32

ext/opcache/jit/zend_jit_helpers.c

@@ -2719,3 +2719,20 @@ static void ZEND_FASTCALL zend_jit_free_trampoline_helper(zend_function *func)
 	zend_string_release_ex(func->common.function_name, 0);
 	zend_free_trampoline(func);
 }
+
+static void ZEND_FASTCALL zend_jit_exception_in_interrupt_handler_helper(void)
+{
+	if (EG(exception)) {
+		/* We have to UNDEF result, because ZEND_HANDLE_EXCEPTION is going to free it */
+		const zend_op *throw_op = EG(opline_before_exception);
+
+		if (throw_op
+		 && throw_op->result_type & (IS_TMP_VAR|IS_VAR)
+		 && throw_op->opcode != ZEND_ADD_ARRAY_ELEMENT
+		 && throw_op->opcode != ZEND_ADD_ARRAY_UNPACK
+		 && throw_op->opcode != ZEND_ROPE_INIT
+		 && throw_op->opcode != ZEND_ROPE_ADD) {
+			ZVAL_UNDEF(ZEND_CALL_VAR(EG(current_execute_data), throw_op->result.var));
+		}
+	}
+}

ext/opcache/jit/zend_jit_x86.dasc

@@ -1768,6 +1768,10 @@ static int zend_jit_interrupt_handler_stub(dasm_State **Dst)
 			|	mov aword A1, FP
 			|	EXT_CALL zend_interrupt_function, r0
 		|.endif
+		|	MEM_OP2_1_ZTS cmp, aword, executor_globals, exception, 0, r0
+		|	je >1
+		|	EXT_CALL zend_jit_exception_in_interrupt_handler_helper, r0
+		|1:
 		|	//ZEND_VM_ENTER();
 		|	//execute_data = EG(current_execute_data);
 		|	MEM_OP2_2_ZTS mov, FP, aword, executor_globals, current_execute_data, r0