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From: DJ Delorie <dj@redhat.com>
To: gdb-patches@sourceware.org
Subject: [v850 sim] correcting psw flags for divide special cases.
Date: Thu, 13 Apr 2006 23:37:00 -0000	[thread overview]
Message-ID: <200604132336.k3DNan1h001282@greed.delorie.com> (raw)


2006-04-13  DJ Delorie  <dj@redhat.com>

	* simops.c (OP_2C207E0): Correct PSW flags for special divu
	conditions.
	(OP_2C007E0): Likewise, for div.
	(OP_28207E0): Likewise, for divhu.
	(OP_28007E0): Likewise, for divh.

Index: simops.c
===================================================================
RCS file: /cvs/src/src/sim/v850/simops.c,v
retrieving revision 1.8
diff -p -U3 -r1.8 simops.c
--- simops.c	18 Jan 2004 14:56:40 -0000	1.8
+++ simops.c	13 Apr 2006 23:34:03 -0000
@@ -2264,19 +2264,20 @@ OP_2C207E0 (void)
   
   if (divide_by == 0)
     {
-      overflow = 1;
-      divide_by  = 1;
+      PSW |= PSW_OV;
     }
+  else
+    {
+      State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
+      State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
   
-  State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
-  State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
-  
-  /* Set condition codes.  */
-  PSW &= ~(PSW_Z | PSW_S | PSW_OV);
+      /* Set condition codes.  */
+      PSW &= ~(PSW_Z | PSW_S | PSW_OV);
   
-  if (overflow)      PSW |= PSW_OV;
-  if (quotient == 0) PSW |= PSW_Z;
-  if (quotient & 0x80000000) PSW |= PSW_S;
+      if (overflow)      PSW |= PSW_OV;
+      if (quotient == 0) PSW |= PSW_Z;
+      if (quotient & 0x80000000) PSW |= PSW_S;
+    }
   
   trace_output (OP_REG_REG_REG);
 
@@ -2291,7 +2292,6 @@ OP_2C007E0 (void)
   signed long int remainder;
   signed long int divide_by;
   signed long int divide_this;
-  int         overflow = 0;
   
   trace_input ("div", OP_REG_REG_REG, 0);
   
@@ -2300,21 +2300,28 @@ OP_2C007E0 (void)
   divide_by   = State.regs[ OP[0] ];
   divide_this = State.regs[ OP[1] ];
   
-  if (divide_by == 0 || (divide_by == -1 && divide_this == (1 << 31)))
+  if (divide_by == 0)
     {
-      overflow  = 1;
-      divide_by = 1;
+      PSW |= PSW_OV;
     }
+  else if (divide_by == -1 && divide_this == (1 << 31))
+    {
+      PSW &= ~PSW_Z;
+      PSW |= PSW_OV | PSW_S;
+      State.regs[ OP[1] ] = (1 << 31);
+      State.regs[ OP[2] >> 11 ] = 0;
+    }
+  else
+    {
+      State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
+      State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
   
-  State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
-  State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
-  
-  /* Set condition codes.  */
-  PSW &= ~(PSW_Z | PSW_S | PSW_OV);
+      /* Set condition codes.  */
+      PSW &= ~(PSW_Z | PSW_S | PSW_OV);
   
-  if (overflow)      PSW |= PSW_OV;
-  if (quotient == 0) PSW |= PSW_Z;
-  if (quotient <  0) PSW |= PSW_S;
+      if (quotient == 0) PSW |= PSW_Z;
+      if (quotient <  0) PSW |= PSW_S;
+    }
   
   trace_output (OP_REG_REG_REG);
 
@@ -2340,19 +2347,20 @@ OP_28207E0 (void)
   
   if (divide_by == 0)
     {
-      overflow = 1;
-      divide_by  = 1;
+      PSW |= PSW_OV;
     }
+  else
+    {
+      State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
+      State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
   
-  State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
-  State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
-  
-  /* Set condition codes.  */
-  PSW &= ~(PSW_Z | PSW_S | PSW_OV);
+      /* Set condition codes.  */
+      PSW &= ~(PSW_Z | PSW_S | PSW_OV);
   
-  if (overflow)      PSW |= PSW_OV;
-  if (quotient == 0) PSW |= PSW_Z;
-  if (quotient & 0x80000000) PSW |= PSW_S;
+      if (overflow)      PSW |= PSW_OV;
+      if (quotient == 0) PSW |= PSW_Z;
+      if (quotient & 0x80000000) PSW |= PSW_S;
+    }
   
   trace_output (OP_REG_REG_REG);
 
@@ -2376,21 +2384,28 @@ OP_28007E0 (void)
   divide_by  = State.regs[ OP[0] ];
   divide_this = EXTEND16 (State.regs[ OP[1] ]);
   
-  if (divide_by == 0 || (divide_by == -1 && divide_this == (1 << 31)))
+  if (divide_by == 0)
     {
-      overflow = 1;
-      divide_by  = 1;
+      PSW |= PSW_OV;
     }
+  else if (divide_by == -1 && divide_this == (1 << 31))
+    {
+      PSW &= ~PSW_Z;
+      PSW |= PSW_OV | PSW_S;
+      State.regs[ OP[1] ] = (1 << 31);
+      State.regs[ OP[2] >> 11 ] = 0;
+    }
+  else
+    {
+      State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
+      State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
   
-  State.regs[ OP[1]       ] = quotient  = divide_this / divide_by;
-  State.regs[ OP[2] >> 11 ] = remainder = divide_this % divide_by;
-  
-  /* Set condition codes.  */
-  PSW &= ~(PSW_Z | PSW_S | PSW_OV);
+      /* Set condition codes.  */
+      PSW &= ~(PSW_Z | PSW_S | PSW_OV);
   
-  if (overflow)      PSW |= PSW_OV;
-  if (quotient == 0) PSW |= PSW_Z;
-  if (quotient <  0) PSW |= PSW_S;
+      if (quotient == 0) PSW |= PSW_Z;
+      if (quotient <  0) PSW |= PSW_S;
+    }
   
   trace_output (OP_REG_REG_REG);
 


             reply	other threads:[~2006-04-13 23:37 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-04-13 23:37 DJ Delorie [this message]
2006-04-14 20:35 ` Daniel Jacobowitz
2006-04-14 20:36   ` Daniel Jacobowitz
2006-04-17 19:35   ` DJ Delorie
2006-04-17 19:49     ` Daniel Jacobowitz
2006-04-17 20:20       ` DJ Delorie
2006-04-18 19:25         ` Daniel Jacobowitz
2006-04-18 19:36           ` DJ Delorie
2006-04-20 13:09             ` Daniel Jacobowitz
2006-05-04 15:40               ` Daniel Jacobowitz
2006-04-18 19:44 ` [v850 sim] REVISED " DJ Delorie

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