From db2a148d9df3d7d1f3423313761f0e2517c1aa2b Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Tue, 16 Jul 2019 20:31:38 -0400 Subject: [PATCH] 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. --- arch/mips64/syscall_arch.h | 25 +++++++++++-------------- arch/mipsn32/syscall_arch.h | 25 +++++++++++-------------- 2 files changed, 22 insertions(+), 28 deletions(-) diff --git a/arch/mips64/syscall_arch.h b/arch/mips64/syscall_arch.h index 99eebc32..a653c31c 100644 --- 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 7b11740f..90823a99 100644 --- 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; -- 2.25.1