[RFA] fix for intel disassembly, truncated BFD_VMA

[RFA] fix for intel disassembly, truncated BFD_VMA

[Michael Snyder]

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This expression needed parentheses.  Without them, it was truncating the
target address of jumps and calls from BFD_VMA to 32-bits.

Disassembly at high addresses is vastly improved.


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2011-02-09  Michael Snyder  <msnyder@vmware.com>

	* i386-dis.c (OP_J): Parenthesize expression to prevent 
	truncated addresses.
	(print_insn): Fix indentation off-by-one.

Index: i386-dis.c
===================================================================
RCS file: /cvs/src/src/opcodes/i386-dis.c,v
retrieving revision 1.257
diff -u -p -u -p -r1.257 i386-dis.c
--- i386-dis.c	18 Jan 2011 17:08:13 -0000	1.257
+++ i386-dis.c	9 Feb 2011 18:28:02 -0000
@@ -1,6 +1,6 @@
 /* Print i386 instructions for GDB, the GNU debugger.
    Copyright 1988, 1989, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
    Free Software Foundation, Inc.
 
    This file is part of the GNU opcodes library.
@@ -11702,9 +11702,9 @@ print_insn (bfd_vma pc, disassemble_info
       modrm.rm = *codep & 7;
     }
 
-   need_vex = 0;
-   need_vex_reg = 0;
-   vex_w_done = 0;
+  need_vex = 0;
+  need_vex_reg = 0;
+  vex_w_done = 0;
 
   if (dp->name == NULL && dp->op[0].bytemode == FLOATCODE)
     {
@@ -13817,7 +13817,7 @@ OP_J (int bytemode, int sizeflag)
       oappend (INTERNAL_DISASSEMBLER_ERROR);
       return;
     }
-  disp = ((start_pc + codep - start_codep + disp) & mask) | segment;
+  disp = ((start_pc + (codep - start_codep) + disp) & mask) | segment;
   set_op (disp, 0);
   print_operand_value (scratchbuf, 1, disp);
   oappend (scratchbuf);

Re: [RFA] fix for intel disassembly, truncated BFD_VMA

[H.J. Lu]

On Wed, Feb 9, 2011 at 10:36 AM, Michael Snyder <msnyder@vmware.com> wrote:
> This expression needed parentheses.  Without them, it was truncating the
> target address of jumps and calls from BFD_VMA to 32-bits.
>
> Disassembly at high addresses is vastly improved.
>
>
> 2011-02-09  Michael Snyder  <msnyder@vmware.com>
>
>        * i386-dis.c (OP_J): Parenthesize expression to prevent
>        truncated addresses.
>        (print_insn): Fix indentation off-by-one.
>
> Index: i386-dis.c
> ===================================================================
> RCS file: /cvs/src/src/opcodes/i386-dis.c,v
> retrieving revision 1.257
> diff -u -p -u -p -r1.257 i386-dis.c
> --- i386-dis.c  18 Jan 2011 17:08:13 -0000      1.257
> +++ i386-dis.c  9 Feb 2011 18:28:02 -0000
> @@ -1,6 +1,6 @@
>  /* Print i386 instructions for GDB, the GNU debugger.
>    Copyright 1988, 1989, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
> -   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
> +   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
>    Free Software Foundation, Inc.
>
>    This file is part of the GNU opcodes library.
> @@ -11702,9 +11702,9 @@ print_insn (bfd_vma pc, disassemble_info
>       modrm.rm = *codep & 7;
>     }
>
> -   need_vex = 0;
> -   need_vex_reg = 0;
> -   vex_w_done = 0;
> +  need_vex = 0;
> +  need_vex_reg = 0;
> +  vex_w_done = 0;
>
>   if (dp->name == NULL && dp->op[0].bytemode == FLOATCODE)
>     {
> @@ -13817,7 +13817,7 @@ OP_J (int bytemode, int sizeflag)
>       oappend (INTERNAL_DISASSEMBLER_ERROR);
>       return;
>     }
> -  disp = ((start_pc + codep - start_codep + disp) & mask) | segment;
> +  disp = ((start_pc + (codep - start_codep) + disp) & mask) | segment;
>   set_op (disp, 0);
>   print_operand_value (scratchbuf, 1, disp);
>   oappend (scratchbuf);
>
>

OK.

Thanks.


-- 
H.J.

Re: [RFA] fix for intel disassembly, truncated BFD_VMA

[Michael Snyder]

H.J. Lu wrote:
> On Wed, Feb 9, 2011 at 10:36 AM, Michael Snyder <msnyder@vmware.com> wrote:
>> This expression needed parentheses.  Without them, it was truncating the
>> target address of jumps and calls from BFD_VMA to 32-bits.
>>
>> Disassembly at high addresses is vastly improved.
>>
>>
>> 2011-02-09  Michael Snyder  <msnyder@vmware.com>
>>
>>        * i386-dis.c (OP_J): Parenthesize expression to prevent
>>        truncated addresses.
>>        (print_insn): Fix indentation off-by-one.
>>
>> Index: i386-dis.c
>> ===================================================================
>> RCS file: /cvs/src/src/opcodes/i386-dis.c,v
>> retrieving revision 1.257
>> diff -u -p -u -p -r1.257 i386-dis.c
>> --- i386-dis.c  18 Jan 2011 17:08:13 -0000      1.257
>> +++ i386-dis.c  9 Feb 2011 18:28:02 -0000
>> @@ -1,6 +1,6 @@
>>  /* Print i386 instructions for GDB, the GNU debugger.
>>    Copyright 1988, 1989, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
>> -   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
>> +   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
>>    Free Software Foundation, Inc.
>>
>>    This file is part of the GNU opcodes library.
>> @@ -11702,9 +11702,9 @@ print_insn (bfd_vma pc, disassemble_info
>>       modrm.rm = *codep & 7;
>>     }
>>
>> -   need_vex = 0;
>> -   need_vex_reg = 0;
>> -   vex_w_done = 0;
>> +  need_vex = 0;
>> +  need_vex_reg = 0;
>> +  vex_w_done = 0;
>>
>>   if (dp->name == NULL && dp->op[0].bytemode == FLOATCODE)
>>     {
>> @@ -13817,7 +13817,7 @@ OP_J (int bytemode, int sizeflag)
>>       oappend (INTERNAL_DISASSEMBLER_ERROR);
>>       return;
>>     }
>> -  disp = ((start_pc + codep - start_codep + disp) & mask) | segment;
>> +  disp = ((start_pc + (codep - start_codep) + disp) & mask) | segment;
>>   set_op (disp, 0);
>>   print_operand_value (scratchbuf, 1, disp);
>>   oappend (scratchbuf);
>>
>>
> 
> OK.

Thanks, committed.

Re: [RFA] fix for intel disassembly, truncated BFD_VMA

[H.J. Lu]

[-- Attachment #1: Type: text/plain, Size: 2169 bytes --]

On Wed, Feb 9, 2011 at 10:43 AM, Michael Snyder <msnyder@vmware.com> wrote:
> H.J. Lu wrote:
>>
>> On Wed, Feb 9, 2011 at 10:36 AM, Michael Snyder <msnyder@vmware.com>
>> wrote:
>>>
>>> This expression needed parentheses.  Without them, it was truncating the
>>> target address of jumps and calls from BFD_VMA to 32-bits.
>>>
>>> Disassembly at high addresses is vastly improved.
>>>
>>>
>>> 2011-02-09  Michael Snyder  <msnyder@vmware.com>
>>>
>>>        * i386-dis.c (OP_J): Parenthesize expression to prevent
>>>        truncated addresses.
>>>        (print_insn): Fix indentation off-by-one.
>>>
>>> Index: i386-dis.c
>>> ===================================================================
>>> RCS file: /cvs/src/src/opcodes/i386-dis.c,v
>>> retrieving revision 1.257
>>> diff -u -p -u -p -r1.257 i386-dis.c
>>> --- i386-dis.c  18 Jan 2011 17:08:13 -0000      1.257
>>> +++ i386-dis.c  9 Feb 2011 18:28:02 -0000
>>> @@ -1,6 +1,6 @@
>>>  /* Print i386 instructions for GDB, the GNU debugger.
>>>    Copyright 1988, 1989, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
>>> -   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
>>> +   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
>>>    Free Software Foundation, Inc.
>>>
>>>    This file is part of the GNU opcodes library.
>>> @@ -11702,9 +11702,9 @@ print_insn (bfd_vma pc, disassemble_info
>>>       modrm.rm = *codep & 7;
>>>     }
>>>
>>> -   need_vex = 0;
>>> -   need_vex_reg = 0;
>>> -   vex_w_done = 0;
>>> +  need_vex = 0;
>>> +  need_vex_reg = 0;
>>> +  vex_w_done = 0;
>>>
>>>   if (dp->name == NULL && dp->op[0].bytemode == FLOATCODE)
>>>     {
>>> @@ -13817,7 +13817,7 @@ OP_J (int bytemode, int sizeflag)
>>>       oappend (INTERNAL_DISASSEMBLER_ERROR);
>>>       return;
>>>     }
>>> -  disp = ((start_pc + codep - start_codep + disp) & mask) | segment;
>>> +  disp = ((start_pc + (codep - start_codep) + disp) & mask) | segment;
>>>   set_op (disp, 0);
>>>   print_operand_value (scratchbuf, 1, disp);
>>>   oappend (scratchbuf);
>>>
>>>
>>
>> OK.
>
>
> Thanks, committed.

I got a hit with a similar case.  I checked this patch into trunk
and 2.26 branch.

-- 
H.J.

[-- Attachment #2: 0001-Add-parentheses-to-prevent-truncated-addresses.patch --]
[-- Type: text/x-patch, Size: 1703 bytes --]

From 89e1725d35e190ab3b746ff5491bc8bd35287f84 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 15 Feb 2016 15:58:42 -0800
Subject: [PATCH] Add parentheses to prevent truncated addresses

	* i386-dis.c (print_insn): Parenthesize expression to prevent
	truncated addresses.
	(OP_J): Likewise.
---
 opcodes/ChangeLog  | 6 ++++++
 opcodes/i386-dis.c | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 24c1680..e9f1578 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,9 @@
+2016-02-15  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* i386-dis.c (print_insn): Parenthesize expression to prevent
+	truncated addresses.
+	(OP_J): Likewise.
+
 2016-02-10  Claudiu Zissulescu  <claziss@synopsys.com>
 	    Janek van Oirschot  <jvanoirs@synopsys.com>
 
diff --git a/opcodes/i386-dis.c b/opcodes/i386-dis.c
index 5f4aed5..de0534c 100644
--- a/opcodes/i386-dis.c
+++ b/opcodes/i386-dis.c
@@ -13644,7 +13644,7 @@ print_insn (bfd_vma pc, disassemble_info *info)
     if (op_index[i] != -1 && op_riprel[i])
       {
 	(*info->fprintf_func) (info->stream, "        # ");
-	(*info->print_address_func) ((bfd_vma) (start_pc + codep - start_codep
+	(*info->print_address_func) ((bfd_vma) (start_pc + (codep - start_codep)
 						+ op_address[op_index[i]]), info);
 	break;
       }
@@ -16158,7 +16158,7 @@ OP_J (int bytemode, int sizeflag)
 	     the displacement is added!  */
 	  mask = 0xffff;
 	  if ((prefixes & PREFIX_DATA) == 0)
-	    segment = ((start_pc + codep - start_codep)
+	    segment = ((start_pc + (codep - start_codep))
 		       & ~((bfd_vma) 0xffff));
 	}
       if (address_mode != mode_64bit
-- 
2.5.0