JIT for FETCH_THIS

Author: dstogov

Zend/zend_vm_def.h

@@ -970,10 +970,6 @@ ZEND_VM_COLD_HELPER(zend_this_not_in_object_context_helper, ANY, ANY)
 
 	SAVE_OPLINE();
 	zend_throw_error(NULL, "Using $this when not in object context");
-	if ((opline+1)->opcode == ZEND_OP_DATA) {
-		FREE_UNFETCHED_OP_DATA();
-	}
-	FREE_UNFETCHED_OP2();
 	UNDEF_RESULT();
 	HANDLE_EXCEPTION();
 }

Zend/zend_vm_execute.h

@@ -746,10 +746,6 @@ static zend_never_inline ZEND_COLD ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL zend_th
 
 	SAVE_OPLINE();
 	zend_throw_error(NULL, "Using $this when not in object context");
-	if ((opline+1)->opcode == ZEND_OP_DATA) {
-		FREE_UNFETCHED_OP((opline+1)->op1_type, (opline+1)->op1.var);
-	}
-	FREE_UNFETCHED_OP(opline->op2_type, opline->op2.var);
 	UNDEF_RESULT();
 	HANDLE_EXCEPTION();
 }

ext/opcache/jit/zend_jit.c

@@ -2812,6 +2812,11 @@ static int zend_jit(const zend_op_array *op_array, zend_ssa *ssa, const zend_op
 							goto jit_failure;
 						}
 						goto done;
+					case ZEND_FETCH_THIS:
+						if (!zend_jit_fetch_this(&dasm_state, opline, op_array)) {
+							goto jit_failure;
+						}
+						goto done;
 					case ZEND_SWITCH_LONG:
 					case ZEND_SWITCH_STRING:
 						if (!zend_jit_switch(&dasm_state, opline, op_array, ssa)) {

ext/opcache/jit/zend_jit_internal.h

@@ -344,6 +344,7 @@ struct _zend_jit_trace_stack_frame {
 #define TRACE_FRAME_MASK_LAST_SEND_BY_VAL    0x00000004
 #define TRACE_FRAME_MASK_RETURN_VALUE_USED   0x00000008
 #define TRACE_FRAME_MASK_RETURN_VALUE_UNUSED 0x00000010
+#define TRACE_FRAME_MASK_THIS_CHECKED        0x00000020
 
 
 #define TRACE_FRAME_INIT(frame, _func, nested, num_args) do { \
@@ -371,6 +372,8 @@ struct _zend_jit_trace_stack_frame {
 	((frame)->_info & TRACE_FRAME_MASK_RETURN_VALUE_USED)
 #define TRACE_FRAME_IS_RETURN_VALUE_UNUSED(frame) \
 	((frame)->_info & TRACE_FRAME_MASK_RETURN_VALUE_UNUSED)
+#define TRACE_FRAME_IS_THIS_CHECKED(frame) \
+	((frame)->_info & TRACE_FRAME_MASK_THIS_CHECKED)
 
 #define TRACE_FRAME_SET_RETURN_SSA_VAR(frame, var) do { \
 		(frame)->_info = var; \
@@ -391,6 +394,9 @@ struct _zend_jit_trace_stack_frame {
 		(frame)->_info |= TRACE_FRAME_MASK_RETURN_VALUE_UNUSED; \
 		(frame)->_info &= ~TRACE_FRAME_MASK_RETURN_VALUE_USED; \
 	} while (0)
+#define TRACE_FRAME_SET_THIS_CHECKED(frame) do { \
+		(frame)->_info |= TRACE_FRAME_MASK_THIS_CHECKED; \
+	} while (0)
 
 typedef struct _zend_jit_globals {
 	zend_jit_trace_stack_frame *current_frame;

ext/opcache/jit/zend_jit_trace.c

@@ -2632,6 +2632,11 @@ static const void *zend_jit_trace(zend_jit_trace_rec *trace_buffer, uint32_t par
 							goto jit_failure;
 						}
 						goto done;
+					case ZEND_FETCH_THIS:
+						if (!zend_jit_fetch_this(&dasm_state, opline, op_array)) {
+							goto jit_failure;
+						}
+						goto done;
 #if 0
 					case ZEND_SWITCH_LONG:
 					case ZEND_SWITCH_STRING:

ext/opcache/jit/zend_jit_x86.dasc

@@ -2101,6 +2101,25 @@ static int zend_jit_mod_by_zero_stub(dasm_State **Dst)
 	return 1;
 }
 
+static int zend_jit_invalid_this_stub(dasm_State **Dst)
+{
+	|->invalid_this:
+	|	UNDEF_OPLINE_RESULT
+	|.if X64
+		|	xor CARG1, CARG1
+		|	LOAD_ADDR CARG2, "Using $this when not in object context"
+		|	EXT_CALL zend_throw_error, r0
+	|.else
+		|	sub r4, 8
+		|	push "Using $this when not in object context"
+		|	push 0
+		|	EXT_CALL zend_throw_error, r0
+		|	add r4, 16
+	|.endif
+	|	jmp ->exception_handler
+	return 1;
+}
+
 static int zend_jit_double_one_stub(dasm_State **Dst)
 {
 	|->one:
@@ -2433,6 +2452,7 @@ static const zend_jit_stub zend_jit_stubs[] = {
 	JIT_STUB(undefined_function),
 	JIT_STUB(negative_shift),
 	JIT_STUB(mod_by_zero),
+	JIT_STUB(invalid_this),
 	JIT_STUB(trace_halt),
 	JIT_STUB(trace_exit),
 	JIT_STUB(trace_escape),
@@ -10553,6 +10573,43 @@ static int zend_jit_strlen(dasm_State **Dst, const zend_op *opline, const zend_o
 	return 1;
 }
 
+static int zend_jit_fetch_this(dasm_State **Dst, const zend_op *opline, const zend_op_array *op_array)
+{
+	zend_jit_addr res_addr = RES_ADDR();
+
+	if (zend_jit_trigger == ZEND_JIT_ON_HOT_TRACE) {
+		if (!JIT_G(current_frame) ||
+		    !TRACE_FRAME_IS_THIS_CHECKED(JIT_G(current_frame))) {
+
+			int32_t exit_point = zend_jit_trace_get_exit_point(opline, opline, NULL);
+			const void *exit_addr = zend_jit_trace_get_exit_addr(exit_point);
+
+			|	cmp byte EX->This.u1.v.type, IS_OBJECT
+			|	jne &exit_addr
+
+			if (JIT_G(current_frame)) {
+				TRACE_FRAME_SET_THIS_CHECKED(JIT_G(current_frame));
+			}
+		}
+	} else {
+
+		|	cmp byte EX->This.u1.v.type, IS_OBJECT
+		|	jne >1
+		|.cold_code
+		|1:
+		|	SAVE_VALID_OPLINE opline, r0
+		|	jmp ->invalid_this
+		|.code
+	}
+
+	|	mov r0, aword EX->This.value.ptr
+	|	SET_ZVAL_PTR res_addr, r0
+	|	SET_ZVAL_TYPE_INFO res_addr, IS_OBJECT_EX
+	|	GC_ADDREF r0
+
+	return 1;
+}
+
 static int zend_jit_switch(dasm_State **Dst, const zend_op *opline, const zend_op_array *op_array, zend_ssa *ssa)
 {
 	HashTable *jumptable = Z_ARRVAL_P(RT_CONSTANT(opline, opline->op2));