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[PATCH 09/15] microblaze: Avoid clobbering register parameters in syscall


The microblaze INTERNAL_SYSCALL macro might clobber the register
parameter if the argument itself might clobber any register (a function
call for instance).

This patch fixes it by using temporary variables for the expressions
between the register assignments (as indicated by GCC documentation,
6.47.5.2 Specifying Registers for Local Variables).

It is similar to the fix done for MIPS (BZ#25523).

Checked with microblaze-linux-gnu and microblazeel-linux-gnu build.
---
 sysdeps/unix/sysv/linux/microblaze/sysdep.h | 63 ++++++++++++++-------
 1 file changed, 42 insertions(+), 21 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/microblaze/sysdep.h b/sysdeps/unix/sysv/linux/microblaze/sysdep.h
index ed873d9dd4..b4a6ee89f1 100644
--- a/sysdeps/unix/sysv/linux/microblaze/sysdep.h
+++ b/sysdeps/unix/sysv/linux/microblaze/sysdep.h
@@ -219,9 +219,10 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall1(name,arg1)                                           \
   ({                                                                          \
+    long __arg1 = (long) (arg1);                                              \
     register long __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
+    register long __r5 __asm__("r5") = __arg1;                                \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r12)                                                 \
@@ -230,10 +231,12 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall2(name,arg1,arg2)                                      \
   ({                                                                          \
+    long __arg1 = (long) (arg1);                                              \
+    long __arg2 = (long) (arg2);                                              \
     register long __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
-    register long __r6 __asm__("r6") = (long)(arg2);                          \
+    register long __r5 __asm__("r5") = __arg1;                                \
+    register long __r6 __asm__("r6") = __arg2;                                \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r6), "r"(__r12)                                      \
@@ -243,11 +246,14 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall3(name,arg1,arg2,arg3)                                 \
   ({                                                                          \
+    long __arg1 = (long) (arg1);                                              \
+    long __arg2 = (long) (arg2);                                              \
+    long __arg3 = (long) (arg3);                                              \
     register long __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
-    register long __r6 __asm__("r6") = (long)(arg2);                          \
-    register long __r7 __asm__("r7") = (long)(arg3);                          \
+    register long __r5 __asm__("r5") = __arg1;                                \
+    register long __r6 __asm__("r6") = __arg2;                                \
+    register long __r7 __asm__("r7") = __arg3;                                \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r12)                           \
@@ -257,12 +263,16 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall4(name,arg1,arg2,arg3,arg4)                            \
   ({                                                                          \
+    long __arg1 = (long) (arg1);                                              \
+    long __arg2 = (long) (arg2);                                              \
+    long __arg3 = (long) (arg3);                                              \
+    long __arg4 = (long) (arg4);                                              \
     register long __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
-    register long __r6 __asm__("r6") = (long)(arg2);                          \
-    register long __r7 __asm__("r7") = (long)(arg3);                          \
-    register long __r8 __asm__("r8") = (long)(arg4);                          \
+    register long __r5 __asm__("r5") = __arg1;                                \
+    register long __r6 __asm__("r6") = __arg2;                                \
+    register long __r7 __asm__("r7") = __arg3;                                \
+    register long __r8 __asm__("r8") = __arg4;                                \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r12)                 \
@@ -272,13 +282,18 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall5(name,arg1,arg2,arg3,arg4,arg5)                       \
   ({                                                                          \
+    long __arg1 = (long) (arg1);                                              \
+    long __arg2 = (long) (arg2);                                              \
+    long __arg3 = (long) (arg3);                                              \
+    long __arg4 = (long) (arg4);                                              \
+    long __arg5 = (long) (arg5);                                              \
     register long __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
-    register long __r6 __asm__("r6") = (long)(arg2);                          \
-    register long __r7 __asm__("r7") = (long)(arg3);                          \
-    register long __r8 __asm__("r8") = (long)(arg4);                          \
-    register long __r9 __asm__("r9") = (long)(arg5);                          \
+    register long __r5 __asm__("r5") = __arg1;                                \
+    register long __r6 __asm__("r6") = __arg2;                                \
+    register long __r7 __asm__("r7") = __arg3;                                \
+    register long __r8 __asm__("r8") = __arg4;                                \
+    register long __r9 __asm__("r9") = __arg5;                                \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r9), "r"(__r12)      \
@@ -288,14 +303,20 @@ SYSCALL_ERROR_LABEL_DCL:                            \
 
 # define inline_syscall6(name,arg1,arg2,arg3,arg4,arg5,arg6)                  \
   ({                                                                          \
+    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 __ret __asm__("r3");                                        \
     register long __r12 __asm__("r12") = name;                                \
-    register long __r5 __asm__("r5") = (long)(arg1);                          \
-    register long __r6 __asm__("r6") = (long)(arg2);                          \
-    register long __r7 __asm__("r7") = (long)(arg3);                          \
-    register long __r8 __asm__("r8") = (long)(arg4);                          \
-    register long __r9 __asm__("r9") = (long)(arg5);                          \
-    register long __r10 __asm__("r10") = (long)(arg6);                        \
+    register long __r5 __asm__("r5") = __arg1;                                \
+    register long __r6 __asm__("r6") = __arg2;                                \
+    register long __r7 __asm__("r7") = __arg3;                                \
+    register long __r8 __asm__("r8") = __arg4;                                \
+    register long __r9 __asm__("r9") = __arg5;                                \
+    register long __r10 __asm__("r10") = __arg6;                              \
     __asm__ __volatile__( "brki r14,8; nop;"                                  \
       : "=r"(__ret)                                                           \
       : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r9), "r"(__r10),     \
-- 
2.17.1


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