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 <schwab@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
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 @@
* 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 @@
: "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 @@
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 @@
#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 @@
#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 @@
!(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 @@
#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..5550aa4f 100644
--- a/arch/m68k/mm/cache.c
+++ b/arch/m68k/mm/cache.c
@@ -52,9 +52,9 @@
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);
