On Fri, Sep 13, 2013 at 05:25:00PM +1000, Kevin Easton wrote:
> If you wanted to collapse the unary and binary variants as you mentioned
> upthread, you could do something like (for the CC_HAVE_ASM_GOTO case):

Indeed, another 11 lines off, awesome!

--- /dev/null
+++ b/arch/x86/include/asm/rmwcc.h
@@ -0,0 +1,41 @@
+#ifndef _ASM_X86_RMWcc
+#define _ASM_X86_RMWcc
+
+#ifdef CC_HAVE_ASM_GOTO
+
+#define __GEN_RMWcc(fullop, var, cc, ...)                              \
+do {                                                                   \
+       asm volatile goto (fullop "; j" cc " %l[cc_label]"              \
+                       : : "m" (var), ## __VA_ARGS__                   \
+                       : "memory" : cc_label);                         \
+       return 0;                                                       \
+cc_label:                                                              \
+       return 1;                                                       \
+} while (0)
+
+#define GEN_UNARY_RMWcc(op, var, arg0, cc)                             \
+       __GEN_RMWcc(op " " arg0, var, cc)
+
+#define GEN_BINARY_RMWcc(op, var, val, arg0, cc)                       \
+       __GEN_RMWcc(op " %1, " arg0, var, cc, "er" (val))
+
+#else /* !CC_HAVE_ASM_GOTO */
+
+#define __GEN_RMWcc(fullop, var, cc, ...)                              \
+do {                                                                   \
+       char c;                                                         \
+       asm volatile (fullop "; set" cc " %1"                           \
+                       : "+m" (var), "=qm" (c)                         \
+                       : __VA_ARGS__ : "memory");                      \
+       return c != 0;                                                  \
+} while (0)
+
+#define GEN_UNARY_RMWcc(op, var, arg0, cc)                             \
+       __GEN_RMWcc(op " " arg0, var, cc)
+
+#define GEN_BINARY_RMWcc(op, var, val, arg0, cc)                       \
+       __GEN_RMWcc(op " %2, " arg0, var, cc, "er" (val))
+
+#endif /* CC_HAVE_ASM_GOTO */
+
+#endif /* _ASM_X86_RMWcc */

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to