diff --git a/include/opcode/ChangeLog b/include/opcode/ChangeLog
index f33c0e65c8..5474c8569a 100644
--- a/include/opcode/ChangeLog
+++ b/include/opcode/ChangeLog
@@ -1,3 +1,7 @@
+2011-06-18  Robin Getz  <robin.getz@analog.com>
+
+	* bfin.h (is_macmod_signed): New func
+
 2011-06-18  Mike Frysinger  <vapier@gentoo.org>
 
 	* bfin.h (is_macmod_pmove): Add missing space before func args.
diff --git a/include/opcode/bfin.h b/include/opcode/bfin.h
index 30bb90d26c..26f019381b 100755
--- a/include/opcode/bfin.h
+++ b/include/opcode/bfin.h
@@ -53,6 +53,12 @@ static inline int is_macmod_hmove (int x)
          || (x == M_TFU) || (x == M_S2RND) || (x == M_ISS2) || (x == M_IH);
 }
 
+static inline int is_macmod_signed (int x)
+{
+  return (x == 0) || (x == M_IS) || (x == M_T) || (x == M_S2RND)
+         || (x == M_ISS2) || (x == M_IH) || (x == M_W32);
+}
+
 /*   dsp32mac
 +----+----+---+---|---+----+----+---|---+---+---+---|---+---+---+---+
 | 1  | 1  | 0 | 0 |.M.| 0  | 0  |.mmod..........|.MM|.P.|.w1|.op1...|
diff --git a/sim/bfin/ChangeLog b/sim/bfin/ChangeLog
index 72bd358446..52b75ee6fa 100644
--- a/sim/bfin/ChangeLog
+++ b/sim/bfin/ChangeLog
@@ -1,3 +1,10 @@
+2011-06-18  Robin Getz  <robin.getz@analog.com>
+
+	* bfin-sim.c (decode_multfunc): Call new is_macmod_signed, and
+	allow MM to sign extend all the time.
+	(decode_macfunc): Likewise.  Drop sign extension of unsigned
+	values.
+
 2011-06-18  Robin Getz  <robin.getz@analog.com>
 
 	* bfin-sim.c (extract_mult): When mmod is M_IH, change the order
diff --git a/sim/bfin/bfin-sim.c b/sim/bfin/bfin-sim.c
index 5b8d601d7d..017ddcad51 100644
--- a/sim/bfin/bfin-sim.c
+++ b/sim/bfin/bfin-sim.c
@@ -1380,8 +1380,8 @@ decode_multfunc (SIM_CPU *cpu, int h0, int h1, int src0, int src1, int mmod,
     }
   val1 = val;
 
-  if (mmod == 0 || mmod == M_IS || mmod == M_T || mmod == M_S2RND
-      || mmod == M_ISS2 || mmod == M_IH || (MM && mmod == M_FU))
+  /* In signed modes, sign extend.  */
+  if (is_macmod_signed (mmod) || MM)
     val1 |= -(val1 & 0x80000000);
 
   if (*psat)
@@ -1579,16 +1579,11 @@ decode_macfunc (SIM_CPU *cpu, int which, int op, int h0, int h1, int src0,
   bu32 sat = 0, tsat, ret;
 
   /* Sign extend accumulator if necessary, otherwise unsigned.  */
-  if (mmod == 0 || mmod == M_T || mmod == M_IS || mmod == M_ISS2
-      || mmod == M_S2RND || mmod == M_IH || mmod == M_W32)
+  if (is_macmod_signed (mmod) || MM)
     acc = get_extended_acc (cpu, which);
   else
     acc = get_unextended_acc (cpu, which);
 
-  if (MM && (mmod == M_T || mmod == M_IS || mmod == M_ISS2
-      || mmod == M_S2RND || mmod == M_IH || mmod == M_W32))
-    acc |= -(acc & 0x80000000);
-
   if (op != 3)
     {
       bu8 sgn0 = (acc >> 31) & 1;