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Date:      Mon, 18 Jun 2012 09:33:39 GMT
From:      Robert Watson <rwatson@FreeBSD.org>
To:        Perforce Change Reviews <perforce@freebsd.org>
Subject:   PERFORCE change 213057 for review
Message-ID:  <201206180933.q5I9XdOk059248@skunkworks.freebsd.org>

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http://p4web.freebsd.org/@@213057?ac=10

Change 213057 by rwatson@rwatson_svr_ctsrd_mipsbuild on 2012/06/18 09:32:59

	Remove XXX comments about pipeline issues with CP2 forwarding; we
	believe these to be fixed in hardware, so nops were removed.  Let
	the comments catch up.

Affected files ...

.. //depot/projects/ctsrd/cheribsd/src/sys/mips/cheri/cp2.h#7 edit

Differences ...

==== //depot/projects/ctsrd/cheribsd/src/sys/mips/cheri/cp2.h#7 (text+ko) ====

@@ -178,15 +178,6 @@
  *
  * XXXRW: C macros are named after capability field names -- hence OTYPE
  * rather than TYPE.  Possibly this is a bug.
- *
- * XXXRW: There is currently no forwarding of general-purpose register
- * operands into capability manipulation instructions.  We therefore have to
- * take care to nop several times after possible loads of values that will be
- * immediately passed into them.
- *
- * XXXRW: We also space all capability instructions with several nops on
- * either side in order to ensure they don't follow through the pipeline too
- * closely.
  */
 #define	CP2_CR_MOVE(crn_to, crn_from)	do {				\
 	if ((crn_to) == 0)						\



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