From 117780eef7740729e803bdcc0d5f2f48137ea8e3 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 8 Jun 2016 12:38:38 -0700 Subject: x86, asm: use bool for bitops and other assembly outputs The gcc people have confirmed that using "bool" when combined with inline assembly always is treated as a byte-sized operand that can be assumed to be 0 or 1, which is exactly what the SET instruction emits. Change the output types and intermediate variables of as many operations as practical to "bool". Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/r/1465414726-197858-3-git-send-email-hpa@linux.intel.com Reviewed-by: Andy Lutomirski Reviewed-by: Borislav Petkov Acked-by: Peter Zijlstra (Intel) --- arch/x86/boot/bitops.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'arch/x86/boot/bitops.h') diff --git a/arch/x86/boot/bitops.h b/arch/x86/boot/bitops.h index 878e4b9940d9..0d41d68131cc 100644 --- a/arch/x86/boot/bitops.h +++ b/arch/x86/boot/bitops.h @@ -16,14 +16,16 @@ #define BOOT_BITOPS_H #define _LINUX_BITOPS_H /* Inhibit inclusion of */ -static inline int constant_test_bit(int nr, const void *addr) +#include + +static inline bool constant_test_bit(int nr, const void *addr) { const u32 *p = (const u32 *)addr; return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0; } -static inline int variable_test_bit(int nr, const void *addr) +static inline bool variable_test_bit(int nr, const void *addr) { - u8 v; + bool v; const u32 *p = (const u32 *)addr; asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr)); -- cgit v1.2.3