Re: [PATCH] local_t : powerpc extension - use long for powerpc32

From: Kumar Gala
Date: Thu Feb 15 2007 - 15:36:37 EST



On Feb 15, 2007, at 2:02 PM, Mathieu Desnoyers wrote:

* Kumar Gala (galak@xxxxxxxxxxxxxxxxxxx) wrote:
is there a reason this isn't local_add_return(long a, local_t *l) on
ppc32?

(same comment for other functions)

- k

no, except that we use the code is taken from atomic.h and used an
int parameter. However, due to the semantics of local_t, we should
manipulate longs instead of ints, even if they are the same size on a
given architecture (ppc32 and mips32 are affectec by this).

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx>

Right, this means we can simply for ppc version down to:

+static __inline__ int local_add_return(int a, local_t *l)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: PPC_LLARX %0,0,%2 # local_add_return\n\
+ add %0,%1,%0\n"
+ PPC405_ERR77(0,%2)
+" PPC_STLCX %0,0,%2 \n\
+ bne- 1b"
+ : "=&r" (t)
+ : "r" (a), "r" (&(l->a.counter))
+ : "cc", "memory");
+
+ return t;
+}

and that should work for both ppc32 & ppc64 and removes the duplication between the two.

- k

-
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