From 729a6688af366f995bd07ce94d825ed895a77d10 Mon Sep 17 00:00:00 2001
From: Xinchen Hui <laruence@gmail.com>
Date: Fri, 5 Jan 2018 12:58:28 +0800
Subject: [PATCH] Optimized FETCH_CLASS before INSTANCEOF out if possible

---
 ext/opcache/Optimizer/sccp.c           | 19 ++++++++++++
 ext/opcache/Optimizer/zend_optimizer.c |  4 +++
 ext/opcache/tests/opt/sccp_024.phpt    | 41 ++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)
 create mode 100644 ext/opcache/tests/opt/sccp_024.phpt

diff --git a/ext/opcache/Optimizer/sccp.c b/ext/opcache/Optimizer/sccp.c
index 3c6c54be771..996eb10ac72 100644
--- a/ext/opcache/Optimizer/sccp.c
+++ b/ext/opcache/Optimizer/sccp.c
@@ -329,6 +329,25 @@ static zend_bool try_replace_op2(
 		if (zend_optimizer_update_op2_const(ctx->scdf.op_array, opline, &zv)) {
 			return 1;
 		} else {
+			switch (opline->opcode) {
+				case ZEND_FETCH_CLASS:
+					if (Z_TYPE(zv) == IS_STRING) {
+						ZEND_ASSERT((opline + 1)->opcode == ZEND_INSTANCEOF);
+						ZEND_ASSERT((opline + 1)->op2.var == opline->result.var);
+						if (zend_optimizer_update_op2_const(ctx->scdf.op_array, opline + 1, &zv)) {
+							zend_ssa_op *next_op = ssa_op + 1;
+							zend_optimizer_remove_live_range_ex(ctx->scdf.op_array, opline->result.var, ssa_op - ctx->scdf.ssa->ops);
+							zend_ssa_unlink_use_chain(ctx->scdf.ssa, next_op - ctx->scdf.ssa->ops, next_op->op2_use);
+							next_op->op2_use = -1;
+							next_op->op2_use_chain = -1;
+							zend_ssa_remove_result_def(ctx->scdf.ssa, ssa_op);
+							MAKE_NOP(opline);
+							return 1;
+						}
+					}
+				default:
+					break;
+			}
 			zval_ptr_dtor_nogc(&zv);
 		}
 	}
diff --git a/ext/opcache/Optimizer/zend_optimizer.c b/ext/opcache/Optimizer/zend_optimizer.c
index 97be113f47a..d5975f14141 100644
--- a/ext/opcache/Optimizer/zend_optimizer.c
+++ b/ext/opcache/Optimizer/zend_optimizer.c
@@ -347,6 +347,10 @@ int zend_optimizer_update_op2_const(zend_op_array *op_array,
 		case ZEND_FAST_CALL:
 			return 0;
 		case ZEND_FETCH_CLASS:
+			if ((opline + 1)->opcode == ZEND_INSTANCEOF &&
+				(opline + 1)->op2.var == opline->result.var) {
+				return 0;
+			}
 		case ZEND_INIT_FCALL_BY_NAME:
 		/*case ZEND_INIT_NS_FCALL_BY_NAME:*/
 		case ZEND_ADD_INTERFACE:
diff --git a/ext/opcache/tests/opt/sccp_024.phpt b/ext/opcache/tests/opt/sccp_024.phpt
new file mode 100644
index 00000000000..f0b34f077b1
--- /dev/null
+++ b/ext/opcache/tests/opt/sccp_024.phpt
@@ -0,0 +1,41 @@
+--TEST--
+SCCP 024: Const replacing to op2 of INSTANCEOF
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.opt_debug_level=0x20000
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+class A {
+	function t($obj) {
+		$a = "A";
+        $b = "self";
+        $c = 1;
+        echo ($obj instanceof $a);
+        echo ($obj instanceof $b);
+        echo ($obj instanceof $c);
+	}
+}
+?>
+--EXPECTF--
+$_main: ; (lines=1, args=0, vars=0, tmps=0)
+    ; (after optimizer)
+    ; %ssccp_024.php:1-13
+L0 (13):    RETURN int(1)
+
+A::t: ; (lines=10, args=1, vars=2, tmps=2)
+    ; (after optimizer)
+    ; %ssccp_024.php:3-10
+L0 (3):     CV0($obj) = RECV 1
+L1 (6):     CV1($c) = QM_ASSIGN int(1)
+L2 (7):     T2 = INSTANCEOF CV0($obj) string("A")
+L3 (7):     ECHO T2
+L4 (8):     T2 = INSTANCEOF CV0($obj) string("self")
+L5 (8):     ECHO T2
+L6 (9):     V3 = FETCH_CLASS (no-autolod) (exception) CV1($c)
+L7 (9):     T2 = INSTANCEOF CV0($obj) V3
+L8 (9):     ECHO T2
+L9 (10):    RETURN null