[igt-dev] [PATCH i-g-t] lib/intel_reg: fix shift undefined behaviour

[Simon Ser]

1<<31 (same as 2<<30) is undefined behaviour in C. When compiling with
GCC and UBSan, it gives this error:

../tools/intel_reg_decode.c: In function ‘ivb_debug_port’:
../tools/intel_reg_decode.c:398:3: error: case label does not reduce to an integer constant
   case PORT_DBG_DRRS_HW_STATE_HIGH:
   ^~~~

This happens because 1<<31 isn't representable as a signed int. Instead,
use am unsigned int.

Signed-off-by: Simon Ser <simon.ser at intel.com>
---
 lib/intel_reg.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/intel_reg.h b/lib/intel_reg.h
index f85fb742..069440cb 100644
--- a/lib/intel_reg.h
+++ b/lib/intel_reg.h
@@ -3383,7 +3383,7 @@ typedef enum {
 #define PORT_DBG                    0x42308
 #define  PORT_DBG_DRRS_HW_STATE_OFF     (0<<30)
 #define  PORT_DBG_DRRS_HW_STATE_LOW     (1<<30)
-#define  PORT_DBG_DRRS_HW_STATE_HIGH    (2<<30)
+#define  PORT_DBG_DRRS_HW_STATE_HIGH    (2U<<30)
 
 /* RC6 residence counters
  */
-- 
2.21.0

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