From 4fbba6fe904d0094ddc4284066b3860d119cbd4a Mon Sep 17 00:00:00 2001
From: WANG Xuerui <git@xen0n.name>
Date: Thu, 13 Feb 2020 00:57:03 +0800
Subject: [PATCH] mips: Fix argument passing for inlined syscalls on Linux [BZ
 #25523]

According to [gcc documentation][1], temporary variables must be used for
the desired content to not be call-clobbered.

Fix the Linux inline syscall templates by adding temporary variables,
much like what x86 did before
(commit 381a0c26d73e0f074c962e0ab53b99a6c327066d).

Tested with gcc 9.2.0, both cross-compiled and natively on Loongson
3A4000.

[1]: https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html
---
 sysdeps/unix/sysv/linux/mips/mips32/sysdep.h  | 30 ++++++---
 .../unix/sysv/linux/mips/mips64/n32/sysdep.h  | 63 ++++++++++++-------
 .../unix/sysv/linux/mips/mips64/n64/sysdep.h  | 63 ++++++++++++-------
 3 files changed, 104 insertions(+), 52 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
index beefcf284b..c275d63f67 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
@@ -178,10 +178,11 @@ union __mips_syscall_return
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
+	register long __a0 asm ("$4") = _arg1;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -202,11 +203,13 @@ union __mips_syscall_return
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -228,12 +231,15 @@ union __mips_syscall_return
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -255,13 +261,17 @@ union __mips_syscall_return
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
+	long _arg4 = (long) (arg4);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
-	register long __a3 asm ("$7") = (long) (arg4);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
+	register long __a3 asm ("$7") = _arg4;				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
index f96636538a..958a889147 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
@@ -138,10 +138,11 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
+	register long long __a0 asm ("$4") = _arg1;			\
 	register long long __a3 asm ("$7");				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -162,11 +163,13 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
+	long long _arg2 = ARGIFY (arg2);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
-	register long long __a1 asm ("$5") = ARGIFY (arg2);		\
+	register long long __a0 asm ("$4") = _arg1;			\
+	register long long __a1 asm ("$5") = _arg2;			\
 	register long long __a3 asm ("$7");				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -188,12 +191,15 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
+	long long _arg2 = ARGIFY (arg2);				\
+	long long _arg3 = ARGIFY (arg3);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
-	register long long __a1 asm ("$5") = ARGIFY (arg2);		\
-	register long long __a2 asm ("$6") = ARGIFY (arg3);		\
+	register long long __a0 asm ("$4") = _arg1;			\
+	register long long __a1 asm ("$5") = _arg2;			\
+	register long long __a2 asm ("$6") = _arg3;			\
 	register long long __a3 asm ("$7");				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -215,13 +221,17 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
+	long long _arg2 = ARGIFY (arg2);				\
+	long long _arg3 = ARGIFY (arg3);				\
+	long long _arg4 = ARGIFY (arg4);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
-	register long long __a1 asm ("$5") = ARGIFY (arg2);		\
-	register long long __a2 asm ("$6") = ARGIFY (arg3);		\
-	register long long __a3 asm ("$7") = ARGIFY (arg4);		\
+	register long long __a0 asm ("$4") = _arg1;			\
+	register long long __a1 asm ("$5") = _arg2;			\
+	register long long __a2 asm ("$6") = _arg3;			\
+	register long long __a3 asm ("$7") = _arg4;			\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
@@ -242,14 +252,19 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
+	long long _arg2 = ARGIFY (arg2);				\
+	long long _arg3 = ARGIFY (arg3);				\
+	long long _arg4 = ARGIFY (arg4);				\
+	long long _arg5 = ARGIFY (arg5);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
-	register long long __a1 asm ("$5") = ARGIFY (arg2);		\
-	register long long __a2 asm ("$6") = ARGIFY (arg3);		\
-	register long long __a3 asm ("$7") = ARGIFY (arg4);		\
-	register long long __a4 asm ("$8") = ARGIFY (arg5);		\
+	register long long __a0 asm ("$4") = _arg1;			\
+	register long long __a1 asm ("$5") = _arg2;			\
+	register long long __a2 asm ("$6") = _arg3;			\
+	register long long __a3 asm ("$7") = _arg4;			\
+	register long long __a4 asm ("$8") = _arg5;			\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
@@ -270,15 +285,21 @@
 	long _sys_result;						\
 									\
 	{								\
+	long long _arg1 = ARGIFY (arg1);				\
+	long long _arg2 = ARGIFY (arg2);				\
+	long long _arg3 = ARGIFY (arg3);				\
+	long long _arg4 = ARGIFY (arg4);				\
+	long long _arg5 = ARGIFY (arg5);				\
+	long long _arg6 = ARGIFY (arg6);				\
 	register long long __s0 asm ("$16") __attribute__ ((unused))	\
 	  = (number);							\
 	register long long __v0 asm ("$2");				\
-	register long long __a0 asm ("$4") = ARGIFY (arg1);		\
-	register long long __a1 asm ("$5") = ARGIFY (arg2);		\
-	register long long __a2 asm ("$6") = ARGIFY (arg3);		\
-	register long long __a3 asm ("$7") = ARGIFY (arg4);		\
-	register long long __a4 asm ("$8") = ARGIFY (arg5);		\
-	register long long __a5 asm ("$9") = ARGIFY (arg6);		\
+	register long long __a0 asm ("$4") = _arg1;			\
+	register long long __a1 asm ("$5") = _arg2;			\
+	register long long __a2 asm ("$6") = _arg3;			\
+	register long long __a3 asm ("$7") = _arg4;			\
+	register long long __a4 asm ("$8") = _arg5;			\
+	register long long __a5 asm ("$9") = _arg6;			\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
index 9d30291f84..f47613deaf 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
@@ -134,10 +134,11 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
+	register long __a0 asm ("$4") = _arg1;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -158,11 +159,13 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -184,12 +187,15 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
 	register long __a3 asm ("$7");					\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
@@ -211,13 +217,17 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
+	long _arg4 = (long) (arg4);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
-	register long __a3 asm ("$7") = (long) (arg4);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
+	register long __a3 asm ("$7") = _arg4;				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
@@ -238,14 +248,19 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
+	long _arg4 = (long) (arg4);					\
+	long _arg5 = (long) (arg5);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
-	register long __a3 asm ("$7") = (long) (arg4);			\
-	register long __a4 asm ("$8") = (long) (arg5);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
+	register long __a3 asm ("$7") = _arg4;				\
+	register long __a4 asm ("$8") = _arg5;				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
@@ -266,15 +281,21 @@
 	long _sys_result;						\
 									\
 	{								\
+	long _arg1 = (long) (arg1);					\
+	long _arg2 = (long) (arg2);					\
+	long _arg3 = (long) (arg3);					\
+	long _arg4 = (long) (arg4);					\
+	long _arg5 = (long) (arg5);					\
+	long _arg6 = (long) (arg6);					\
 	register long __s0 asm ("$16") __attribute__ ((unused))		\
 	  = (number);							\
 	register long __v0 asm ("$2");					\
-	register long __a0 asm ("$4") = (long) (arg1);			\
-	register long __a1 asm ("$5") = (long) (arg2);			\
-	register long __a2 asm ("$6") = (long) (arg3);			\
-	register long __a3 asm ("$7") = (long) (arg4);			\
-	register long __a4 asm ("$8") = (long) (arg5);			\
-	register long __a5 asm ("$9") = (long) (arg6);			\
+	register long __a0 asm ("$4") = _arg1;				\
+	register long __a1 asm ("$5") = _arg2;				\
+	register long __a2 asm ("$6") = _arg3;				\
+	register long __a3 asm ("$7") = _arg4;				\
+	register long __a4 asm ("$8") = _arg5;				\
+	register long __a5 asm ("$9") = _arg6;				\
 	__asm__ volatile (						\
 	".set\tnoreorder\n\t"						\
 	v0_init								\
-- 
2.24.1
