commit: 2a3535069e33d8b416f406c159ce924427315303 From: Andreas Schwab <[email protected]> Date: Mon, 9 Jan 2012 15:10:15 +0100 Subject: m68k: Fix assembler constraint to prevent overeager gcc optimisation
Passing the address of a variable as an operand to an asm statement doesn't mark the value of this variable as used, so gcc may optimize its initialisation away. Fix this by using the "m" constraint instead. Signed-off-by: Andreas Schwab <[email protected]> Signed-off-by: Geert Uytterhoeven <[email protected]> Cc: [email protected] --- arch/m68k/atari/config.c | 8 ++++---- arch/m68k/kernel/process_mm.c | 4 ++-- arch/m68k/kernel/process_no.c | 4 ++-- arch/m68k/kernel/traps.c | 36 +++++++++++++++++------------------- arch/m68k/mm/cache.c | 6 +++--- 5 files changed, 28 insertions(+), 30 deletions(-) diff --git a/arch/m68k/atari/config.c b/arch/m68k/atari/config.c index 4203d10..c4ac15c 100644 --- a/arch/m68k/atari/config.c +++ b/arch/m68k/atari/config.c @@ -414,9 +414,9 @@ void __init config_atari(void) * FDC val = 4 -> Supervisor only */ asm volatile ("\n" " .chip 68030\n" - " pmove %0@,%/tt1\n" + " pmove %0,%/tt1\n" " .chip 68k" - : : "a" (&tt1_val)); + : : "m" (tt1_val)); } else { asm volatile ("\n" " .chip 68040\n" @@ -569,10 +569,10 @@ static void atari_reset(void) : "d0"); } else asm volatile ("\n" - " pmove %0@,%%tc\n" + " pmove %0,%%tc\n" " jmp %1@" : /* no outputs */ - : "a" (&tc_val), "a" (reset_addr)); + : "m" (tc_val), "a" (reset_addr)); } diff --git a/arch/m68k/kernel/process_mm.c b/arch/m68k/kernel/process_mm.c index 1bc223a..aa4ffb8 100644 --- a/arch/m68k/kernel/process_mm.c +++ b/arch/m68k/kernel/process_mm.c @@ -189,8 +189,8 @@ void flush_thread(void) current->thread.fs = __USER_DS; if (!FPU_IS_EMU) asm volatile (".chip 68k/68881\n\t" - "frestore %0@\n\t" - ".chip 68k" : : "a" (&zero)); + "frestore %0\n\t" + ".chip 68k" : : "m" (zero)); } /* diff --git a/arch/m68k/kernel/process_no.c b/arch/m68k/kernel/process_no.c index 69c1803..5e1078c 100644 --- a/arch/m68k/kernel/process_no.c +++ b/arch/m68k/kernel/process_no.c @@ -163,8 +163,8 @@ void flush_thread(void) #ifdef CONFIG_FPU if (!FPU_IS_EMU) asm volatile (".chip 68k/68881\n\t" - "frestore %0@\n\t" - ".chip 68k" : : "a" (&zero)); + "frestore %0\n\t" + ".chip 68k" : : "m" (zero)); #endif } diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c index 89362f2..eb67469 100644 --- a/arch/m68k/kernel/traps.c +++ b/arch/m68k/kernel/traps.c @@ -552,13 +552,13 @@ static inline void bus_error030 (struct frame *fp) #ifdef DEBUG asm volatile ("ptestr %3,%2@,#7,%0\n\t" - "pmove %%psr,%1@" - : "=a&" (desc) - : "a" (&temp), "a" (addr), "d" (ssw)); + "pmove %%psr,%1" + : "=a&" (desc), "=m" (temp) + : "a" (addr), "d" (ssw)); #else asm volatile ("ptestr %2,%1@,#7\n\t" - "pmove %%psr,%0@" - : : "a" (&temp), "a" (addr), "d" (ssw)); + "pmove %%psr,%0" + : "=m" (temp) : "a" (addr), "d" (ssw)); #endif mmusr = temp; @@ -605,20 +605,18 @@ static inline void bus_error030 (struct frame *fp) !(ssw & RW) ? "write" : "read", addr, fp->ptregs.pc, ssw); asm volatile ("ptestr #1,%1@,#0\n\t" - "pmove %%psr,%0@" - : /* no outputs */ - : "a" (&temp), "a" (addr)); + "pmove %%psr,%0" + : "=m" (temp) + : "a" (addr)); mmusr = temp; printk ("level 0 mmusr is %#x\n", mmusr); #if 0 - asm volatile ("pmove %%tt0,%0@" - : /* no outputs */ - : "a" (&tlong)); + asm volatile ("pmove %%tt0,%0" + : "=m" (tlong)); printk("tt0 is %#lx, ", tlong); - asm volatile ("pmove %%tt1,%0@" - : /* no outputs */ - : "a" (&tlong)); + asm volatile ("pmove %%tt1,%0" + : "=m" (tlong)); printk("tt1 is %#lx\n", tlong); #endif #ifdef DEBUG @@ -668,13 +666,13 @@ static inline void bus_error030 (struct frame *fp) #ifdef DEBUG asm volatile ("ptestr #1,%2@,#7,%0\n\t" - "pmove %%psr,%1@" - : "=a&" (desc) - : "a" (&temp), "a" (addr)); + "pmove %%psr,%1" + : "=a&" (desc), "=m" (temp) + : "a" (addr)); #else asm volatile ("ptestr #1,%1@,#7\n\t" - "pmove %%psr,%0@" - : : "a" (&temp), "a" (addr)); + "pmove %%psr,%0" + : "=m" (temp) : "a" (addr)); #endif mmusr = temp; diff --git a/arch/m68k/mm/cache.c b/arch/m68k/mm/cache.c index 5437fff..5550aa4 100644 --- a/arch/m68k/mm/cache.c +++ b/arch/m68k/mm/cache.c @@ -52,9 +52,9 @@ static unsigned long virt_to_phys_slow(unsigned long vaddr) unsigned long *descaddr; asm volatile ("ptestr %3,%2@,#7,%0\n\t" - "pmove %%psr,%1@" - : "=a&" (descaddr) - : "a" (&mmusr), "a" (vaddr), "d" (get_fs().seg)); + "pmove %%psr,%1" + : "=a&" (descaddr), "=m" (mmusr) + : "a" (vaddr), "d" (get_fs().seg)); if (mmusr & (MMU_I|MMU_B|MMU_L)) return 0; descaddr = phys_to_virt((unsigned long)descaddr); -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
