deduplicate mips64/n32 syscall clobbered register lists

this patch is not purely non-functional changes, since before, $8 and
$9 were wrongly in the clobberlist for syscalls with fewer than 5 or 6
arguments. of course it's impossible for syscalls to have different
clobbers depending on their number of arguments. the clobberlist for
the recently-added 5- and 6-argument forms was correct, and for the 0-
to 4-argument forms was erroneously copied from the mips o32 ABI where
the additional arguments had to be passed on the stack.

in making this change, I reviewed the kernel sources, and $8 and $9
are always saved for 64-bit kernels since they're part of the syscall
argument list for n32 and n64 ABIs.

diff --git a/arch/mips64/syscall_arch.h b/arch/mips64/syscall_arch.h
index 99eebc3..a653c31 100644 (file)
--- a/arch/mips64/syscall_arch.h
+++ b/arch/mips64/syscall_arch.h
@@ -46,6 +46,10 @@ static void __stat_fix(struct kernel_stat *kst, struct stat *st)
        st->st_blocks = kst->st_blocks;
 }
 
+#define SYSCALL_CLOBBERLIST \
+       "$1", "$3", "$10", "$11", "$12", "$13", \
+       "$14", "$15", "$24", "$25", "hi", "lo", "memory"
+
 static inline long __syscall0(long n)
 {
        register long r7 __asm__("$7");
@@ -53,8 +57,7 @@ static inline long __syscall0(long n)
        __asm__ __volatile__ (
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        return r7 ? -r2 : r2;
 }
 
@@ -67,8 +70,7 @@ static inline long __syscall1(long n, long a)
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        return r7 ? -r2 : r2;
 }
 
@@ -88,8 +90,7 @@ static inline long __syscall2(long n, long a, long b)
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
 
        if (r7) return -r2;
        ret = r2;
@@ -117,8 +118,7 @@ static inline long __syscall3(long n, long a, long b, long c)
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
 
        if (r7) return -r2;
        ret = r2;
@@ -148,8 +148,7 @@ static inline long __syscall4(long n, long a, long b, long c, long d)
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
 
        if (r7) return -r2;
        ret = r2;
@@ -182,8 +181,7 @@ static inline long __syscall5(long n, long a, long b, long c, long d, long e)
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6), "r"(r8)
-               : "$1", "$3", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
 
        if (r7) return -r2;
        ret = r2;
@@ -217,8 +215,7 @@ static inline long __syscall6(long n, long a, long b, long c, long d, long e, lo
                "daddu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6), "r"(r8), "r"(r9)
-               : "$1", "$3", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
 
        if (r7) return -r2;
        ret = r2;

diff --git a/arch/mipsn32/syscall_arch.h b/arch/mipsn32/syscall_arch.h
index 7b11740..90823a9 100644 (file)
--- a/arch/mipsn32/syscall_arch.h
+++ b/arch/mipsn32/syscall_arch.h
@@ -15,6 +15,10 @@ static inline void __stat_fix(long p)
 }
 #endif
 
+#define SYSCALL_CLOBBERLIST \
+       "$1", "$3", "$10", "$11", "$12", "$13", \
+       "$14", "$15", "$24", "$25", "hi", "lo", "memory"
+
 static inline long __syscall0(long n)
 {
        register long r7 __asm__("$7");
@@ -22,8 +26,7 @@ static inline long __syscall0(long n)
        __asm__ __volatile__ (
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        return r7 ? -r2 : r2;
 }
 
@@ -36,8 +39,7 @@ static inline long __syscall1(long n, long a)
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        return r7 ? -r2 : r2;
 }
 
@@ -51,8 +53,7 @@ static inline long __syscall2(long n, long a, long b)
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        if (r7) return -r2;
        long ret = r2;
        if (n == SYS_stat || n == SYS_fstat || n == SYS_lstat) __stat_fix(b);
@@ -70,8 +71,7 @@ static inline long __syscall3(long n, long a, long b, long c)
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        if (r7) return -r2;
        long ret = r2;
        if (n == SYS_stat || n == SYS_fstat || n == SYS_lstat) __stat_fix(b);
@@ -89,8 +89,7 @@ static inline long __syscall4(long n, long a, long b, long c, long d)
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6)
-               : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        if (r7) return -r2;
        long ret = r2;
        if (n == SYS_stat || n == SYS_fstat || n == SYS_lstat) __stat_fix(b);
@@ -110,8 +109,7 @@ static inline long __syscall5(long n, long a, long b, long c, long d, long e)
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6), "r"(r8)
-               : "$1", "$3", "$9", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        if (n == SYS_stat || n == SYS_fstat || n == SYS_lstat) __stat_fix(b);
        if (n == SYS_newfstatat) __stat_fix(c);
        return r2;
@@ -130,8 +128,7 @@ static inline long __syscall6(long n, long a, long b, long c, long d, long e, lo
                "addu $2,$0,%2 ; syscall"
                : "=&r"(r2), "=r"(r7) : "ir"(n), "0"(r2), "1"(r7),
                  "r"(r4), "r"(r5), "r"(r6), "r"(r8), "r"(r9)
-               : "$1", "$3", "$10", "$11", "$12", "$13",
-                 "$14", "$15", "$24", "$25", "hi", "lo", "memory");
+               : SYSCALL_CLOBBERLIST);
        if (n == SYS_stat || n == SYS_fstat || n == SYS_lstat) __stat_fix(b);
        if (n == SYS_newfstatat) __stat_fix(c);
        return r2;