Hybrid use of registers

1. one **hybrid** solution of register usage
After the discussion with Dmitry, we may want to propose one hybrid
solution of register usage.

1) Following the x86 implementation, we define REG0/1/2 to be the
scratch registers. Clever tricks are utilized in x86 implementation for
better register allocation. Note that we define REG0/1/2 as x8/9/10. One
reason is that R0 and FCARG1 should be distinguished.

2) Temporary registers are also reserved(i.e. they are excluded from the
candidates of register allocator), and they would be used due to the
different addressing modes in AArch64.

2. update the 'make clean' target.

3. remove the unnecessary AArch64 related macros in zend_jit_internal.h.

[ci skip]

Change-Id: I627157b88b2344530d705751eb7f73a223ed83e5
CustomizedGitHooks: yes

Author: shqking

build/Makefile.global

@@ -117,6 +117,7 @@ clean:
 	find . -name .libs -a -type d|xargs rm -rf
 	rm -f libphp.la $(SAPI_CLI_PATH) $(SAPI_CGI_PATH) $(SAPI_LITESPEED_PATH) $(SAPI_FPM_PATH) $(OVERALL_TARGET) modules/* libs/*
 	rm -f ext/opcache/jit/zend_jit_x86.c
+	rm -f ext/opcache/jit/zend_jit_arm64.c
 
 distclean: clean
 	rm -f Makefile config.cache config.log config.status Makefile.objects Makefile.fragments libtool main/php_config.h main/internal_functions_cli.c main/internal_functions.c Zend/zend_dtrace_gen.h Zend/zend_dtrace_gen.h.bak Zend/zend_config.h
@@ -125,8 +126,6 @@ distclean: clean
 	rm -f scripts/man1/phpize.1 scripts/php-config scripts/man1/php-config.1 sapi/cli/php.1 sapi/cgi/php-cgi.1 sapi/phpdbg/phpdbg.1 ext/phar/phar.1 ext/phar/phar.phar.1
 	rm -f sapi/fpm/php-fpm.conf sapi/fpm/init.d.php-fpm sapi/fpm/php-fpm.service sapi/fpm/php-fpm.8 sapi/fpm/status.html
 	rm -f ext/phar/phar.phar ext/phar/phar.php
-	rm -f ext/opcache/jit/zend_jit_x86.c
-	rm -f ext/opcache/jit/zend_jit_arm64.c
 	if test "$(srcdir)" != "$(builddir)"; then \
 	  rm -f ext/phar/phar/phar.inc; \
 	fi