[aandrejevic] 59856: [SOFT386] Implement short conditional jump opcodes.

Author: aandrejevic
Date: Wed Aug 28 17:52:21 2013
New Revision: 59856

URL: http://svn.reactos.org/svn/reactos?rev=59856&view=rev
Log:
[SOFT386]
Implement short conditional jump opcodes.

Modified:
    branches/ntvdm/lib/soft386/opcodes.c
    branches/ntvdm/lib/soft386/opcodes.h

Modified: branches/ntvdm/lib/soft386/opcodes.c
URL: http://svn.reactos.org/svn/reactos/branches/ntvdm/lib/soft386/opcodes.c?rev=...
==============================================================================
--- branches/ntvdm/lib/soft386/opcodes.c	[iso-8859-1] (original)
+++ branches/ntvdm/lib/soft386/opcodes.c	[iso-8859-1] Wed Aug 28 17:52:21 2013
@@ -136,22 +136,22 @@
     NULL, // TODO: OPCODE 0x6D NOT SUPPORTED
     NULL, // TODO: OPCODE 0x6E NOT SUPPORTED
     NULL, // TODO: OPCODE 0x6F NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x70 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x71 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x72 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x73 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x74 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x75 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x76 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x77 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x78 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x79 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7A NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7B NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7C NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7D NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7E NOT SUPPORTED
-    NULL, // TODO: OPCODE 0x7F NOT SUPPORTED
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
+    Soft386OpcodeShortConditionalJmp,
     NULL, // TODO: OPCODE 0x80 NOT SUPPORTED
     NULL, // TODO: OPCODE 0x81 NOT SUPPORTED
     NULL, // TODO: OPCODE 0x82 NOT SUPPORTED
@@ -648,3 +648,95 @@

return TRUE;
 }
+
+BOOLEAN
+FASTCALL
+Soft386OpcodeShortConditionalJmp(PSOFT386_STATE State, UCHAR Opcode)
+{
+    BOOLEAN Jump = FALSE;
+    CHAR Offset = 0;
+
+    /* Make sure this is the right instruction */
+    ASSERT((Opcode & 0xF0) == 0x70);
+
+    /* Fetch the offset */
+    if (!Soft386FetchByte(State, (PUCHAR)&Offset))
+    {
+        /* An exception occurred */
+        return FALSE;
+    }
+
+    switch ((Opcode & 0x0F) >> 1)
+    {
+        /* JO / JNO */
+        case 0:
+        {
+            Jump = State->Flags.Of;
+            break;
+        }
+
+        /* JC / JNC */
+        case 1:
+        {
+            Jump = State->Flags.Cf;
+            break;
+        }
+
+        /* JZ / JNZ */
+        case 2:
+        {
+            Jump = State->Flags.Zf;
+            break;
+        }
+
+        /* JBE / JNBE */
+        case 3:
+        {
+            Jump = State->Flags.Cf || State->Flags.Zf;
+            break;
+        }
+
+        /* JS / JNS */
+        case 4:
+        {
+            Jump = State->Flags.Sf;
+            break;
+        }
+
+        /* JP / JNP */
+        case 5:
+        {
+            Jump = State->Flags.Pf;
+            break;
+        }
+
+        /* JL / JNL */
+        case 6:
+        {
+            Jump = State->Flags.Sf != State->Flags.Of;
+            break;
+        }
+
+        /* JLE / JNLE */
+        case 7:
+        {
+            Jump = (State->Flags.Sf != State->Flags.Of) || State->Flags.Zf;
+            break;
+        }
+    }
+
+    if ((Opcode & 0xF0) & 1)
+    {
+        /* Invert the result */
+        Jump = !Jump;
+    }
+
+    if (Jump)
+    {
+        /* Move the instruction pointer */        
+        State->InstPtr.Long += Offset;
+    }
+
+    /* Return success */
+    return TRUE;
+}

Modified: branches/ntvdm/lib/soft386/opcodes.h
URL: http://svn.reactos.org/svn/reactos/branches/ntvdm/lib/soft386/opcodes.h?rev=...
==============================================================================
--- branches/ntvdm/lib/soft386/opcodes.h	[iso-8859-1] (original)
+++ branches/ntvdm/lib/soft386/opcodes.h	[iso-8859-1] Wed Aug 28 17:52:21 2013
@@ -79,4 +79,12 @@
     UCHAR Opcode
 );

+BOOLEAN
+FASTCALL
+Soft386OpcodeShortConditionalJmp
+(
+    PSOFT386_STATE State,
+    UCHAR Opcode
+);
+
 #endif // _OPCODES_H_