DTrace: re-merge remainder of r249367 (original from Illumos).

Bring back some important fixes from Illumos:

3022 DTrace: keys should not affect the sort order when sorting by value
3023 it should be possible to dereference dynamic variables
3024 D integer narrowing needs some work

We particularly avoid the LD_NOLAZYLOAD changes that Illumos made
as those don't apply to FreeBSD and were causing problems in
interactive mode.

Illumos Revision:	13758:23432da34147

Reference:

https://www.illumos.org/issues/3022
https://www.illumos.org/issues/3023
https://www.illumos.org/issues/3024

MFC after:	1 month
Tested by:	markj

1 files changed, 6 insertions, 24 deletions

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_aggregate.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_aggregate.c
index 42b6645..b0f2b4a 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_aggregate.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_aggregate.c
@@ -26,6 +26,7 @@
 
 /*
  * Copyright (c) 2011, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #include <stdlib.h>
@@ -894,33 +895,14 @@ dt_aggregate_valcmp(const void *lhs, const void *rhs)
 	caddr_t rdata = rh->dtahe_data.dtada_data;
 	dtrace_recdesc_t *lrec, *rrec;
 	int64_t *laddr, *raddr;
-	int rval, i;
-
-	if ((rval = dt_aggregate_hashcmp(lhs, rhs)) != 0)
-		return (rval);
-
-	if (lagg->dtagd_nrecs > ragg->dtagd_nrecs)
-		return (DT_GREATERTHAN);
-
-	if (lagg->dtagd_nrecs < ragg->dtagd_nrecs)
-		return (DT_LESSTHAN);
+	int rval;
 
-	for (i = 0; i < lagg->dtagd_nrecs; i++) {
-		lrec = &lagg->dtagd_rec[i];
-		rrec = &ragg->dtagd_rec[i];
+	assert(lagg->dtagd_nrecs == ragg->dtagd_nrecs);
 
-		if (lrec->dtrd_offset < rrec->dtrd_offset)
-			return (DT_LESSTHAN);
-
-		if (lrec->dtrd_offset > rrec->dtrd_offset)
-			return (DT_GREATERTHAN);
+	lrec = &lagg->dtagd_rec[lagg->dtagd_nrecs - 1];
+	rrec = &ragg->dtagd_rec[ragg->dtagd_nrecs - 1];
 
-		if (lrec->dtrd_action < rrec->dtrd_action)
-			return (DT_LESSTHAN);
-
-		if (lrec->dtrd_action > rrec->dtrd_action)
-			return (DT_GREATERTHAN);
-	}
+	assert(lrec->dtrd_action == rrec->dtrd_action);
 
 	laddr = (int64_t *)(uintptr_t)(ldata + lrec->dtrd_offset);
 	raddr = (int64_t *)(uintptr_t)(rdata + rrec->dtrd_offset);