Description:
------------
I found performance regression caused by a series of git commits of Dec 6, 2016.

The measurement is based on bench.php from php itself. The purpose is to execute all the benchmark functions 30 times:

--- /Users/box/php-src/Zend/bench.php	2016-02-02 18:31:19.000000000 +0800
+++ bench.php	2016-03-17 16:08:58.000000000 +0800
@@ -366,7 +366,7 @@
   $num = number_format($end-$start,3);
   $pad = str_repeat(" ", 24-strlen($name)-strlen($num));
 
-  echo $name.$pad.$num."\n";
+  //echo $name.$pad.$num."\n";
 	ob_start();
   return getmicrotime();
 }
@@ -382,6 +382,7 @@
 }
 
 $t0 = $t = start_test();
+for ($i=0;$i<30;++$i){
 simple();
 $t = end_test($t, "simple");
 simplecall();
@@ -417,6 +418,7 @@
 sieve(30);
 $t = end_test($t, "sieve(30)");
 strcat(200000);
+}
 $t = end_test($t, "strcat(200000)");
 total($t0, "Total");
 ?>

I ran bench.php on a Mac Pro with 12x2.7 Xeon E5 under OS X El Capitan 10.11.6.

The compiler is gcc-5.4.0:

/opt/bin/gcc -v
Using built-in specs.
COLLECT_GCC=/opt/bin/gcc
COLLECT_LTO_WRAPPER=/opt/libexec/gcc/x86_64-apple-darwin15.6.0/5.4.0/lto-wrapper
Target: x86_64-apple-darwin15.6.0
Configured with: ../gcc-5.4.0/configure --prefix=/opt --enable-languages=c,c++,objc,obj-c++
Thread model: posix
gcc version 5.4.0 (GCC) 

The configure script is:

YACC=/usr/local/bin/bison CC=/opt/bin/gcc ./configure --prefix=/opt/php7 --enable-opcache --without-sqlite3 --without-pdo-sqlite --disable-phar --without-pear

For git fe084168d0e7de28dc0efdd58635748de414ac9e:

$ /opt/php7/bin/php bench.php
------------------------
Total             13.853

For git a722970033a8dabb5956625e89655b8eacc38e3a:

$ /opt/php7/bin/php bench.php
------------------------
Total             14.432

For git 1113d589dc356cab3abd0f03d311e6205ad1178c:

$ /opt/php7/bin/php bench.php
------------------------
Total             14.793

For git b149001ffd3acf5ba3262e361cc012910ede77da:

$ /opt/php7/bin/php bench.php
------------------------
Total             15.076

and for the version of the time I wrote this bug report:

$ /opt/php7/bin/php bench.php                    
------------------------
Total             15.353

There is a 10%+ performance loss since then.