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[Aanjhan Ranganathan <aanjhan@xxxxxxxxxx>]

- Log -----------------------------------------------------------------
commit 5d0aafb931d03d7487accdb0d2d331e105a8d68b
Author: Aanjhan Ranganathan <aanjhan@xxxxxxxxx>
Date:   Fri Sep 24 23:16:30 2010 +0200

   Fixes bug LP: #579320. See change log file for details.

diff --git a/ChangeLog b/ChangeLog
index 7681e26..6c5783b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2010-09-24  Aanjhan Ranganathan  <aanjhan@xxxxxxxxxxxxx>

+       * src/8085-instructions.c: CMP instruction should not check and
+       set S, P and AC flags as there is no result that is computed. It
+       affects only C and Z flags. Hence removed most code in that
+       function. Fixes bug LP: #579320.
+
       * src/8085-instructions.c: Fixed the long standing DAA
       bug. Followed http://www.ray.masmcode.com/BCDdaa.html plus had to
       ensure the addition operation on the accumulator must be done
diff --git a/src/8085-instructions.c b/src/8085-instructions.c
index 4c5c042..157e0ad 100644
--- a/src/8085-instructions.c
+++ b/src/8085-instructions.c
@@ -502,19 +502,16 @@ _eef_inst_func_xra (eef_addr_t opnd_addr, gchar sec)
 static gint
 _eef_inst_func_cmp_i (eef_addr_t opnd_addr, eef_data_t data)
 {
-  _eef_find_and_set_flags (sys.reg.a);
-
-  sys.flag.s = (sys.reg.a < data);
-
-  _eef_flag_check_and_set_aux_c (sys.reg.a, data, '-');

+  /* Since this is just comparison, there is no "result"
+     that affects the S, P and AC flags is present. Hence
+     no need to check and set flags */
  if (sys.reg.a < data)
-       sys.flag.c = 1, sys.flag.z = 0;
+    sys.flag.c = 1, sys.flag.z = 0;
  else if (sys.reg.a > data)
-       sys.flag.c = 0, sys.flag.z = 0;
+         sys.flag.c = 0, sys.flag.z = 0;
  else
-       sys.flag.c = 0, sys.flag.z = 1;
-
+         sys.flag.c = 0, sys.flag.z = 1;
  return 0;
 }


-----------------------------------------------------------------------

Summary of changes:
 ChangeLog               |    5 +++++
 src/8085-instructions.c |   15 ++++++---------
 2 files changed, 11 insertions(+), 9 deletions(-)


** Changed in: gnusim8085
       Status: New => Fix Committed

** Changed in: gnusim8085
     Assignee: Aanjhan Ranganathan (aanjhan) => Onkar Shinde (onkarshinde)

-- 
CMP flags not working like SUB with signed numbers
https://bugs.launchpad.net/bugs/579320
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Status in gnusim8085: Fix Committed

Bug description:
MVI A,001h
MVI B,0FEh
CMP B
SUB B

flags after CMP not the same as SUB.