From: H.J. Lu <hjl.tools@gmail.com>
Date: Wed, 16 Dec 2015 13:19:57 +0000 (-0800)
Subject: Add REGISTERS_CLOBBERED_BY_SYSCALL for x86-64
X-Git-Tag: glibc-2.23~117
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d29d57eed9a6acb646663a02b7eb2bece2c433dc;p=thirdparty%2Fglibc.git

Add REGISTERS_CLOBBERED_BY_SYSCALL for x86-64

X86-64 system calls use a different calling convention, which clobbers
CC, %r11 an %rcx registers.  Define REGISTERS_CLOBBERED_BY_SYSCALL for
x86-64 inline asm statements.

	* sysdeps/unix/sysv/linux/x86_64/sysdep.h
	(REGISTERS_CLOBBERED_BY_SYSCALL): New.
	(INTERNAL_SYSCALL_NCS): Use it.
	(INTERNAL_SYSCALL_NCS_TYPES): Likewise.
---

diff --git a/ChangeLog b/ChangeLog
index 21e217a7c18..17b04cd45fb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-12-16  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* sysdeps/unix/sysv/linux/x86_64/sysdep.h
+	(REGISTERS_CLOBBERED_BY_SYSCALL): New.
+	(INTERNAL_SYSCALL_NCS): Use it.
+	(INTERNAL_SYSCALL_NCS_TYPES): Likewise.
+
 2015-12-16  Florian Weimer  <fweimer@redhat.com>
 
 	[BZ #19243]
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
index fc132f6791f..c364d0816a7 100644
--- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
@@ -218,6 +218,9 @@
 # undef INTERNAL_SYSCALL_DECL
 # define INTERNAL_SYSCALL_DECL(err) do { } while (0)
 
+/* Registers clobbered by syscall.  */
+# define REGISTERS_CLOBBERED_BY_SYSCALL "cc", "r11", "cx"
+
 # define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
   ({									      \
     unsigned long int resultvar;					      \
@@ -226,7 +229,7 @@
     asm volatile (							      \
     "syscall\n\t"							      \
     : "=a" (resultvar)							      \
-    : "0" (name) ASM_ARGS_##nr : "memory", "cc", "r11", "cx");		      \
+    : "0" (name) ASM_ARGS_##nr : "memory", REGISTERS_CLOBBERED_BY_SYSCALL);   \
     (long int) resultvar; })
 # undef INTERNAL_SYSCALL
 # define INTERNAL_SYSCALL(name, err, nr, args...) \
@@ -240,7 +243,7 @@
     asm volatile (							      \
     "syscall\n\t"							      \
     : "=a" (resultvar)							      \
-    : "0" (name) ASM_ARGS_##nr : "memory", "cc", "r11", "cx");		      \
+    : "0" (name) ASM_ARGS_##nr : "memory", REGISTERS_CLOBBERED_BY_SYSCALL);   \
     (long int) resultvar; })
 # undef INTERNAL_SYSCALL_TYPES
 # define INTERNAL_SYSCALL_TYPES(name, err, nr, args...) \