[Xen-devel] [PATCH for-4.13 3/6] xen/arm: cpuerrata: Match register size with value size in check_workaround_*

[Julien Grall <julien.grall@xxxxxxx>]

Clang is pickier than GCC for the register size in asm statement. It
expects the register size to match the value size.

The asm statement expects a 32-bit (resp. 64-bit) value on Arm32
(resp. Arm64) whereas the value is a boolean (Clang consider to be
32-bit).

It would be possible to impose 32-bit register for both architecture
but this require the code to use __OP32. However, it does not really
improve the assembly generated. Instead, replace switch the variable
to use register_t.

Signed-off-by: Julien Grall <julien.grall@xxxxxxx>

---
    Changes in v2:
        - Use !! per Stefano's request
---
 xen/include/asm-arm/cpuerrata.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xen/include/asm-arm/cpuerrata.h b/xen/include/asm-arm/cpuerrata.h
index 55ddfda272..0896fe6e25 100644
--- a/xen/include/asm-arm/cpuerrata.h
+++ b/xen/include/asm-arm/cpuerrata.h
@@ -14,14 +14,14 @@ static inline bool check_workaround_##erratum(void)         
    \
         return false;                                           \
     else                                                        \
     {                                                           \
-        bool ret;                                               \
+        register_t ret;                                         \
                                                                 \
         asm volatile (ALTERNATIVE("mov %0, #0",                 \
                                   "mov %0, #1",                 \
                                   feature)                      \
                       : "=r" (ret));                            \
                                                                 \
-        return unlikely(ret);                                   \
+        return unlikely(!!ret);                                 \
     }                                                           \
 }
 
-- 
2.11.0


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel