Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2a41b6dc authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: bitops: Remove non relevant comments 



commit 80f42084 removed the ARC bitops microoptimization but failed
to prune the comments to same effect

Fixes: 80f42084 ("ARC: Make ARC bitops "safer" (add anti-optimization)")
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 7423cc0c

arch/arc/include/asm/bitops.h

+0 −15
Original line number Diff line number Diff line
@@ -35,21 +35,6 @@ static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\ 
									\

	m += nr >> 5;							\

									\

	/*								\

	 * ARC ISA micro-optimization:					\

	 *								\

	 * Instructions dealing with bitpos only consider lower 5 bits	\

	 * e.g (x << 33) is handled like (x << 1) by ASL instruction	\

	 *  (mem pointer still needs adjustment to point to next word)	\

	 *								\

	 * Hence the masking to clamp @nr arg can be elided in general.	\

	 *								\

	 * However if @nr is a constant (above assumed in a register),	\

	 * and greater than 31, gcc can optimize away (x << 33) to 0,	\

	 * as overflow, given the 32-bit ISA. Thus masking needs to be	\

	 * done for const @nr, but no code is generated due to gcc	\

	 * const prop.							\

	 */								\

	nr &= 0x1f;							\

									\

	__asm__ __volatile__(						\