Commit 169d1a4a authored by Helge Deller's avatar Helge Deller
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parisc: Provide an extru_safe() macro to extract unsigned bits 



The extru instruction leaves the most significant 32 bits of the
target register in an undefined state on PA 2.0 systems.
Provide a macro to safely use extru on 32- and 64-bit machines.

Suggested-by: default avatarJohn David Anglin <dave.anglin@bell.net>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 8d192bec

arch/parisc/include/asm/assembly.h

+11 −0
Original line number Diff line number Diff line
@@ -147,6 +147,17 @@ 
	extrd,u \r, 63-(\sa), 64-(\sa), \t

	.endm



	/* Extract unsigned for 32- and 64-bit

	 * The extru instruction leaves the most significant 32 bits of the

	 * target register in an undefined state on PA 2.0 systems. */

	.macro extru_safe r, p, len, t

#ifdef CONFIG_64BIT

	extrd,u	\r, 32+(\p), \len, \t

#else

	extru	\r, \p, \len, \t

#endif

	.endm



	/* load 32-bit 'value' into 'reg' compensating for the ldil

	 * sign-extension when running in wide mode.

	 * WARNING!! neither 'value' nor 'reg' can be expressions