sim: bfin: fix sign extension with 16bit acc add insns

The current implementation attempts to handle the 16bit sign extension
itself.  Unfortunately, it gets it right in some cases.  So rather than
fix that logic, just drop it in favor of using 16bit signed casts.  Now
gcc will take care of getting the logic right.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/sim/bfin/ChangeLog b/sim/bfin/ChangeLog
index a28da1a..7a4aea7 100644 (file)
--- a/sim/bfin/ChangeLog
+++ b/sim/bfin/ChangeLog
@@ -1,3 +1,10 @@
+2011-03-28  Robin Getz  <robin.getz@analog.com>
+
+       * bfin-sim.c (decode_dsp32alu_0): Cast high 16bits of A0.W to bs16
+       and add to casted low 16bits of A0.L and store in val0.  Cast high
+       16bits of A1.W to bs16 and add to casted low 16bits of A1.L and
+       store in val1.  Delete bit checks of val0 and val1.
+
 2011-03-26  Robin Getz  <robin.getz@analog.com>
 
        * bfin-sim.c (decode_dsp32alu_0): Set result to 0x7FFFFFFF when

diff --git a/sim/bfin/bfin-sim.c b/sim/bfin/bfin-sim.c
index 1555dc2..27112c6 100644 (file)
--- a/sim/bfin/bfin-sim.c
+++ b/sim/bfin/bfin-sim.c
@@ -4523,23 +4523,16 @@ decode_dsp32alu_0 (SIM_CPU *cpu, bu16 iw0, bu16 iw1)
     }
   else if (aop == 1 && aopcde == 12)
     {
-      bu32 val0 = ((AWREG (0) >> 16) + (AWREG (0) & 0xFFFF)) & 0xFFFF;
-      bu32 val1 = ((AWREG (1) >> 16) + (AWREG (1) & 0xFFFF)) & 0xFFFF;
+      bs32 val0 = (bs16)(AWREG (0) >> 16) + (bs16)AWREG (0);
+      bs32 val1 = (bs16)(AWREG (1) >> 16) + (bs16)AWREG (1);
 
       TRACE_INSN (cpu, "R%i = A1.L + A1.H, R%i = A0.L + A0.H;", dst1, dst0);
 
       if (dst0 == dst1)
        illegal_instruction_combination (cpu);
 
-      if (val0 & 0x8000)
-       val0 |= 0xFFFF0000;
-
-      if (val1 & 0x8000)
-       val1 |= 0xFFFF0000;
-
       SET_DREG (dst0, val0);
       SET_DREG (dst1, val1);
-      /* XXX: ASTAT ?  */
     }
   else if (aopcde == 1)
     {