aboutsummaryrefslogtreecommitdiff
path: root/sim/bfin
diff options
context:
space:
mode:
authorMike Frysinger <vapier@gentoo.org>2011-03-27 04:03:05 +0000
committerMike Frysinger <vapier@gentoo.org>2011-03-27 04:03:05 +0000
commit36aef94270988051fc9186dfaf4d1e4493e02086 (patch)
tree84f8515b76b0401576cd21294278d266af6c4ad5 /sim/bfin
parentf65d3d6b99f2399eb80708faea6f5e361244e8de (diff)
downloadgdb-36aef94270988051fc9186dfaf4d1e4493e02086.zip
gdb-36aef94270988051fc9186dfaf4d1e4493e02086.tar.gz
gdb-36aef94270988051fc9186dfaf4d1e4493e02086.tar.bz2
sim: bfin: handle saturation with RND12 sub insns
The current handling of the subtraction insn with the RND12 modifier works when saturation isn't involved. So add handling for this edge case to match the hardware. Signed-off-by: Robin Getz <robin.getz@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'sim/bfin')
-rw-r--r--sim/bfin/ChangeLog5
-rw-r--r--sim/bfin/bfin-sim.c7
2 files changed, 11 insertions, 1 deletions
diff --git a/sim/bfin/ChangeLog b/sim/bfin/ChangeLog
index 008edf0..a28da1a 100644
--- a/sim/bfin/ChangeLog
+++ b/sim/bfin/ChangeLog
@@ -1,5 +1,10 @@
2011-03-26 Robin Getz <robin.getz@analog.com>
+ * bfin-sim.c (decode_dsp32alu_0): Set result to 0x7FFFFFFF when
+ the result was 0x80000000 for RND12 subtraction.
+
+2011-03-26 Robin Getz <robin.getz@analog.com>
+
* bfin-sim.c (decode_dsp32alu_0): Set VS when V is set.
2011-03-24 Mike Frysinger <vapier@gentoo.org>
diff --git a/sim/bfin/bfin-sim.c b/sim/bfin/bfin-sim.c
index 7e747ff..1555dc2 100644
--- a/sim/bfin/bfin-sim.c
+++ b/sim/bfin/bfin-sim.c
@@ -4009,7 +4009,12 @@ decode_dsp32alu_0 (SIM_CPU *cpu, bu16 iw0, bu16 iw1)
/* If subtract, just invert and add one. */
if (aop & 0x1)
- val1 = ~val1 + 1;
+ {
+ if (val1 == 0x80000000)
+ val1 = 0x7FFFFFFF;
+ else
+ val1 = ~val1 + 1;
+ }
/* Get the sign bits, since we need them later. */
sBit1 = !!(val0 & 0x80000000);