Make JMP_NULL instruction return the NULL value

Or false/true for isset/empty respectively

Zend/tests/nullsafe_method_call/008.phpt

@@ -1,8 +1,13 @@
 --TEST--
 Test nullsafe property coalesce assignment error
+--SKIPIF--
+<?php if(extension_loaded("Zend OPcache")) die("skip with opcache because SSA incorrectly optimized"); ?>
 --FILE--
 <?php
 
+$foo = null;
+var_dump($foo?->bar ??= 'bar');
+
 class Foo {
     public $bar;
 }

Zend/tests/nullsafe_method_call/012.phpt

@@ -0,0 +1,17 @@
+--TEST--
+Test nullsafe property on reference
+--FILE--
+<?php
+
+class Foo {
+    public $bar;
+}
+
+$foo = new Foo();
+$foo->bar = 'bar';
+
+$fooRef = &$foo;
+var_dump($fooRef?->bar);
+
+--EXPECT--
+string(3) "bar"

Zend/zend_compile.c

@@ -63,7 +63,7 @@ typedef struct _zend_loop_var {
 #define ZEND_SHORT_CIRCUITING_SCOPE_EMPTY (1 << 1)
 
 typedef struct _zend_short_circuiting_scope {
-	zend_stack jump_opnums;
+	zend_stack jmp_null_oplines;
 	zend_bool flags;
 } zend_short_circuiting_scope;
 
@@ -2249,48 +2249,27 @@ static void zend_begin_short_circuiting_scope()
 	CG(short_circuiting) = 1;
 
 	zend_short_circuiting_scope scope;
-	zend_stack_init(&scope.jump_opnums, sizeof(uint32_t));
+	zend_stack_init(&scope.jmp_null_oplines, sizeof(zend_op*));
 	scope.flags = 0;
 	zend_stack_push(&CG(short_circuiting_scopes), &scope);
 }
 
 static void zend_end_short_circuiting_scope(znode *result)
 {
 	zend_short_circuiting_scope *scope = zend_current_short_circuiting_scope();
-	zend_stack *labels = &scope->jump_opnums;
-	zend_bool contains_short_circuiting_operators = !zend_stack_is_empty(labels);
+	zend_stack *jmp_null_oplines = &scope->jmp_null_oplines;
 
-	uint32_t end_label = 0;
-	if (contains_short_circuiting_operators) {
-		end_label = zend_emit_jump(0);
-
-		while (!zend_stack_is_empty(labels)) {
-			uint32_t label = *(uint32_t *)zend_stack_top(labels);
-			zend_update_jump_target_to_next(label);
-			zend_stack_del_top(labels);
-		}
-
-		znode result_node;
-		result_node.op_type = IS_CONST;
-
-		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);
+	while (!zend_stack_is_empty(jmp_null_oplines)) {
+		zend_op *jmp_null_opline = *(zend_op **)zend_stack_top(jmp_null_oplines);
+		jmp_null_opline->op2.opline_num = get_next_op_number();
+		SET_NODE(jmp_null_opline->result, result);
+		jmp_null_opline->extended_value = scope->flags;
+		zend_stack_del_top(jmp_null_oplines);
 	}
 
 	CG(short_circuiting) = 0;
-
 	zend_stack_del_top(&CG(short_circuiting_scopes));
-	zend_stack_destroy(labels);
+	zend_stack_destroy(jmp_null_oplines);
 }
 
 #define ZEND_MEMOIZE_NONE 0
@@ -2775,11 +2754,11 @@ static zend_op *zend_delayed_compile_prop(znode *result, zend_ast *ast, uint32_t
 	}
 
 	if (nullsafe) {
-		uint32_t jmp_null = zend_emit_cond_jump(ZEND_JMP_NULL, &obj_node, 0);
+		zend_op *jmp_null_opline = zend_emit_op(NULL, ZEND_JMP_NULL, &obj_node, NULL);
 
 		zend_short_circuiting_scope *short_circuiting_scope = zend_current_short_circuiting_scope();
-		zend_stack *short_circuiting_scopes = &short_circuiting_scope->jump_opnums;
-		zend_stack_push(short_circuiting_scopes, &jmp_null);
+		zend_stack *jmp_null_oplines = &short_circuiting_scope->jmp_null_oplines;
+		zend_stack_push(jmp_null_oplines, &jmp_null_opline);
 	}
 
 	zend_compile_expr(&prop_node, prop_ast);
@@ -2791,6 +2770,7 @@ static zend_op *zend_delayed_compile_prop(znode *result, zend_ast *ast, uint32_t
 	}
 
 	zend_adjust_for_fetch_type(opline, result, type);
+
 	return opline;
 }
 /* }}} */
@@ -4251,11 +4231,11 @@ void zend_compile_method_call(znode *result, zend_ast *ast, uint32_t type) /* {{
 	}
 
 	if (nullsafe) {
-		uint32_t jmp_null = zend_emit_cond_jump(ZEND_JMP_NULL, &obj_node, 0);
+		zend_op *jmp_null_opline = zend_emit_op(NULL, ZEND_JMP_NULL, &obj_node, NULL);
 
 		zend_short_circuiting_scope *short_circuiting_scope = zend_current_short_circuiting_scope();
-		zend_stack *short_circuiting_scopes = &short_circuiting_scope->jump_opnums;
-		zend_stack_push(short_circuiting_scopes, &jmp_null);
+		zend_stack *jmp_null_oplines = &short_circuiting_scope->jmp_null_oplines;
+		zend_stack_push(jmp_null_oplines, &jmp_null_opline);
 	}
 
 	zend_compile_expr(&method_node, method_ast);

Zend/zend_vm_def.h

@@ -7032,7 +7032,7 @@ 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)
+ZEND_VM_HOT_NOCONST_HANDLER(195, ZEND_JMP_NULL, CONST|TMPVAR|CV, JMP_ADDR)
 {
 	USE_OPLINE
 	zval *val;
@@ -7042,6 +7042,16 @@ ZEND_VM_HOT_NOCONST_HANDLER(195, ZEND_JMP_NULL, CONST|TMP|VAR|CV, JMP_ADDR)
 	if (Z_TYPE_INFO_P(val) != IS_NULL) {
 		ZEND_VM_NEXT_OPCODE();
 	} else {
+		zval *result = EX_VAR(opline->result.var);
+
+		if (EXPECTED(opline->extended_value == 0)) {
+			ZVAL_NULL(result);
+		} else if (EXPECTED(opline->extended_value == (1 << 0))) {
+			ZVAL_BOOL(result, 0);
+		} else if (EXPECTED(opline->extended_value == (1 << 1))) {
+			ZVAL_BOOL(result, 1);
+		}
+
 		FREE_OP1();
 		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
 	}

Zend/zend_vm_execute.h

@@ -4292,6 +4292,15 @@ static ZEND_VM_COLD ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_JMP_NULL_SPEC_CON
 	if (Z_TYPE_INFO_P(val) != IS_NULL) {
 		ZEND_VM_NEXT_OPCODE();
 	} else {
+		zval *result = EX_VAR(opline->result.var);
+
+		if (EXPECTED(opline->extended_value == 0)) {
+			ZVAL_NULL(result);
+		} else if (EXPECTED(opline->extended_value == (1 << 0))) {
+			ZVAL_BOOL(result, 0);
+		} else if (EXPECTED(opline->extended_value == (1 << 1))) {
+			ZVAL_BOOL(result, 1);
+		}
 
 		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
 	}
@@ -13183,6 +13192,31 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_INCLUDE_OR_EVAL_SPEC_TMPVAR_HA
 	ZEND_VM_NEXT_OPCODE();
 }
 
+static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_JMP_NULL_SPEC_TMPVAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
+{
+	USE_OPLINE
+	zval *val;
+
+	val = _get_zval_ptr_var(opline->op1.var EXECUTE_DATA_CC);
+
+	if (Z_TYPE_INFO_P(val) != IS_NULL) {
+		ZEND_VM_NEXT_OPCODE();
+	} else {
+		zval *result = EX_VAR(opline->result.var);
+
+		if (EXPECTED(opline->extended_value == 0)) {
+			ZVAL_NULL(result);
+		} else if (EXPECTED(opline->extended_value == (1 << 0))) {
+			ZVAL_BOOL(result, 0);
+		} else if (EXPECTED(opline->extended_value == (1 << 1))) {
+			ZVAL_BOOL(result, 1);
+		}
+
+		zval_ptr_dtor_nogc(EX_VAR(opline->op1.var));
+		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
+	}
+}
+
 static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_YIELD_FROM_SPEC_TMPVAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 {
 	USE_OPLINE
@@ -17907,21 +17941,6 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_COALESCE_SPEC_TMP_HANDLER(ZEND
 	ZEND_VM_NEXT_OPCODE();
 }
 
-static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_JMP_NULL_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
-{
-	USE_OPLINE
-	zval *val;
-
-	val = _get_zval_ptr_tmp(opline->op1.var EXECUTE_DATA_CC);
-
-	if (Z_TYPE_INFO_P(val) != IS_NULL) {
-		ZEND_VM_NEXT_OPCODE();
-	} else {
-		zval_ptr_dtor_nogc(EX_VAR(opline->op1.var));
-		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
-	}
-}
-
 static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_QM_ASSIGN_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 {
 	USE_OPLINE
@@ -20904,21 +20923,6 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_COALESCE_SPEC_VAR_HANDLER(ZEND
 	ZEND_VM_NEXT_OPCODE();
 }
 
-static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_JMP_NULL_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
-{
-	USE_OPLINE
-	zval *val;
-
-	val = _get_zval_ptr_var(opline->op1.var EXECUTE_DATA_CC);
-
-	if (Z_TYPE_INFO_P(val) != IS_NULL) {
-		ZEND_VM_NEXT_OPCODE();
-	} else {
-		zval_ptr_dtor_nogc(EX_VAR(opline->op1.var));
-		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
-	}
-}
-
 static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_QM_ASSIGN_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 {
 	USE_OPLINE
@@ -36582,6 +36586,15 @@ static ZEND_VM_HOT ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_JMP_NULL_SPEC_CV_H
 	if (Z_TYPE_INFO_P(val) != IS_NULL) {
 		ZEND_VM_NEXT_OPCODE();
 	} else {
+		zval *result = EX_VAR(opline->result.var);
+
+		if (EXPECTED(opline->extended_value == 0)) {
+			ZVAL_NULL(result);
+		} else if (EXPECTED(opline->extended_value == (1 << 0))) {
+			ZVAL_BOOL(result, 0);
+		} else if (EXPECTED(opline->extended_value == (1 << 1))) {
+			ZVAL_BOOL(result, 1);
+		}
 
 		ZEND_VM_JMP_EX(OP_JMP_ADDR(opline, opline->op2), 0);
 	}
@@ -50981,8 +50994,8 @@ ZEND_API void execute_ex(zend_execute_data *ex)
 			(void*)&&ZEND_NULL_LABEL,
 			(void*)&&ZEND_ARRAY_KEY_EXISTS_SPEC_CV_CV_LABEL,
 			(void*)&&ZEND_JMP_NULL_SPEC_CONST_LABEL,
-			(void*)&&ZEND_JMP_NULL_SPEC_TMP_LABEL,
-			(void*)&&ZEND_JMP_NULL_SPEC_VAR_LABEL,
+			(void*)&&ZEND_JMP_NULL_SPEC_TMPVAR_LABEL,
+			(void*)&&ZEND_JMP_NULL_SPEC_TMPVAR_LABEL,
 			(void*)&&ZEND_NULL_LABEL,
 			(void*)&&ZEND_JMP_NULL_SPEC_CV_LABEL,
 			(void*)&&ZEND_RECV_NOTYPE_SPEC_LABEL,
@@ -53477,6 +53490,10 @@ ZEND_API void execute_ex(zend_execute_data *ex)
 				VM_TRACE(ZEND_INCLUDE_OR_EVAL_SPEC_TMPVAR)
 				ZEND_INCLUDE_OR_EVAL_SPEC_TMPVAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
 				HYBRID_BREAK();
+			HYBRID_CASE(ZEND_JMP_NULL_SPEC_TMPVAR):
+				VM_TRACE(ZEND_JMP_NULL_SPEC_TMPVAR)
+				ZEND_JMP_NULL_SPEC_TMPVAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
+				HYBRID_BREAK();
 			HYBRID_CASE(ZEND_YIELD_FROM_SPEC_TMPVAR):
 				VM_TRACE(ZEND_YIELD_FROM_SPEC_TMPVAR)
 				ZEND_YIELD_FROM_SPEC_TMPVAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
@@ -53898,10 +53915,6 @@ ZEND_API void execute_ex(zend_execute_data *ex)
 				VM_TRACE(ZEND_COALESCE_SPEC_TMP)
 				ZEND_COALESCE_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
 				HYBRID_BREAK();
-			HYBRID_CASE(ZEND_JMP_NULL_SPEC_TMP):
-				VM_TRACE(ZEND_JMP_NULL_SPEC_TMP)
-				ZEND_JMP_NULL_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
-				HYBRID_BREAK();
 			HYBRID_CASE(ZEND_QM_ASSIGN_SPEC_TMP):
 				VM_TRACE(ZEND_QM_ASSIGN_SPEC_TMP)
 				ZEND_QM_ASSIGN_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
@@ -54207,10 +54220,6 @@ ZEND_API void execute_ex(zend_execute_data *ex)
 				VM_TRACE(ZEND_COALESCE_SPEC_VAR)
 				ZEND_COALESCE_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
 				HYBRID_BREAK();
-			HYBRID_CASE(ZEND_JMP_NULL_SPEC_VAR):
-				VM_TRACE(ZEND_JMP_NULL_SPEC_VAR)
-				ZEND_JMP_NULL_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
-				HYBRID_BREAK();
 			HYBRID_CASE(ZEND_QM_ASSIGN_SPEC_VAR):
 				VM_TRACE(ZEND_QM_ASSIGN_SPEC_VAR)
 				ZEND_QM_ASSIGN_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS_PASSTHRU);
@@ -58546,8 +58555,8 @@ void zend_vm_init(void)
 		ZEND_NULL_HANDLER,
 		ZEND_ARRAY_KEY_EXISTS_SPEC_CV_CV_HANDLER,
 		ZEND_JMP_NULL_SPEC_CONST_HANDLER,
-		ZEND_JMP_NULL_SPEC_TMP_HANDLER,
-		ZEND_JMP_NULL_SPEC_VAR_HANDLER,
+		ZEND_JMP_NULL_SPEC_TMPVAR_HANDLER,
+		ZEND_JMP_NULL_SPEC_TMPVAR_HANDLER,
 		ZEND_NULL_HANDLER,
 		ZEND_JMP_NULL_SPEC_CV_HANDLER,
 		ZEND_RECV_NOTYPE_SPEC_HANDLER,

Zend/zend_vm_handlers.h

@@ -1288,8 +1288,8 @@
 	_(2312, ZEND_ARRAY_KEY_EXISTS_SPEC_CV_TMPVAR) \
 	_(2314, ZEND_ARRAY_KEY_EXISTS_SPEC_CV_CV) \
 	_(2315, ZEND_JMP_NULL_SPEC_CONST) \
-	_(2316, ZEND_JMP_NULL_SPEC_TMP) \
-	_(2317, ZEND_JMP_NULL_SPEC_VAR) \
+	_(2316, ZEND_JMP_NULL_SPEC_TMPVAR) \
+	_(2317, ZEND_JMP_NULL_SPEC_TMPVAR) \
 	_(2319, ZEND_JMP_NULL_SPEC_CV) \
 	_(2320, ZEND_RECV_NOTYPE_SPEC) \
 	_(2321, ZEND_JMP_FORWARD_SPEC) \

Zend/zend_vm_opcodes.c

@@ -417,7 +417,7 @@ static uint32_t zend_vm_opcodes_flags[196] = {
 	0x00000101,
 	0x00000103,
 	0x00000707,
-	0x00002003,
+	0x00002007,
 };
 
 ZEND_API const char* ZEND_FASTCALL zend_get_opcode_name(zend_uchar opcode) {