xtensa: ISS: improve simcall assembly

Drop redundant result moving from inline assembly, use a1 and b1 values
as return value and errno value respectively.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/platforms/iss/include/platform/simcall.h b/arch/xtensa/platforms/iss/include/platform/simcall.h
index 2ba4585..111bcc5 100644 (file)
--- a/arch/xtensa/platforms/iss/include/platform/simcall.h
+++ b/arch/xtensa/platforms/iss/include/platform/simcall.h
@@ -66,19 +66,17 @@ static int errno;
 
 static inline int __simc(int a, int b, int c, int d)
 {
-       int ret;
        register int a1 asm("a2") = a;
        register int b1 asm("a3") = b;
        register int c1 asm("a4") = c;
        register int d1 asm("a5") = d;
        __asm__ __volatile__ (
                        "simcall\n"
-                       "mov %0, a2\n"
-                       "mov %1, a3\n"
-                       : "=a" (ret), "=a" (errno), "+r"(a1), "+r"(b1)
+                       : "+r"(a1), "+r"(b1)
                        : "r"(c1), "r"(d1)
                        : "memory");
-       return ret;
+       errno = b1;
+       return a1;
 }
 
 static inline int simc_exit(int exit_code)