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Merge branch 'parisc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 

Pull parisc build fix from Helge Deller:
 "This unbreaks the kernel compilation on parisc with gcc-4.9"

* 'parisc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: fix out-of-register compiler error in ldcw inline assembler function
This commit is contained in:
Linus Torvalds 2014-12-26 13:41:05 -08:00
parent 08b022a965 45db07382a
commit 58628a7831
1 changed files with 10 additions and 3 deletions
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13
arch/parisc/include/asm/ldcw.h
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@ -33,11 +33,18 @@
#endif /*!CONFIG_PA20*/
/* LDCW, the only atomic read-write operation PA-RISC has. *sigh*. */
/* LDCW, the only atomic read-write operation PA-RISC has. *sigh*.
We don't explicitly expose that "*a" may be written as reload
fails to find a register in class R1_REGS when "a" needs to be
reloaded when generating 64-bit PIC code. Instead, we clobber
memory to indicate to the compiler that the assembly code reads
or writes to items other than those listed in the input and output
operands. This may pessimize the code somewhat but __ldcw is
usually used within code blocks surrounded by memory barriors. */
#define __ldcw(a) ({ \
unsigned __ret; \
__asm__ __volatile__(__LDCW " 0(%2),%0" \
: "=r" (__ret), "+m" (*(a)) : "r" (a)); \
__asm__ __volatile__(__LDCW " 0(%1),%0" \
: "=r" (__ret) : "r" (a) : "memory"); \
__ret; \
})