Index: gold/ChangeLog
===================================================================
RCS file: /cvs/src/src/gold/ChangeLog,v
retrieving revision 1.1017
diff -r1.1017 ChangeLog
0a1,6
> 2012-12-19  Ben Cheng  <bccheng@google.com>
> 
> 	* arm.cc (Target_arm::attributes_accept_div): New function.
> 	(Target_arm::attributes_forbid_div): New function.
> 	(Target_arm::merge_object_attributes): Merge the Tag_DIV_use attribute		using the same new functions as what bfd/elf32_arm.c does.
> 
Index: gold/arm.cc
===================================================================
RCS file: /cvs/src/src/gold/arm.cc,v
retrieving revision 1.160
diff -r1.160 arm.cc
2800a2801,2812
>   // Query attributes object to see if integer divide instructions may be
>   // present in an object.
>   static bool
>   attributes_accept_div(int arch, int profile,
> 			const Object_attribute* div_attr);
> 
>   // Query attributes object to see if integer divide instructions are
>   // forbidden to be in the object.  This is not the inverse of
>   // attributes_accept_div.
>   static bool
>   attributes_forbid_div(const Object_attribute* div_attr);
> 
10384a10397,10438
> // Query attributes object to see if integer divide instructions may be
> // present in an object.
> 
> template<bool big_endian>
> bool
> Target_arm<big_endian>::attributes_accept_div(int arch, int profile,
>     const Object_attribute* div_attr)
> {
>   switch (div_attr->int_value())
>     {
>     case 0:
>       /* Integer divide allowed if instruction contained in archetecture.  */
>       if (arch == elfcpp::TAG_CPU_ARCH_V7 && (profile == 'R' || profile == 'M'))
>         return true;
>       else if (arch >= elfcpp::TAG_CPU_ARCH_V7E_M)
>         return true;
>       else
>         return false;
> 
>     case 1:
>       /* Integer divide explicitly prohibited.  */
>       return false;
> 
>     default:
>       /* Unrecognised case - treat as allowing divide everywhere.  */
>     case 2:
>       /* Integer divide allowed in ARM state.  */
>       return true;
>     }
> }
> 
> // Query attributes object to see if integer divide instructions are
> // forbidden to be in the object.  This is not the inverse of
> // attributes_accept_div.
> 
> template<bool big_endian>
> bool
> Target_arm<big_endian>::attributes_forbid_div(const Object_attribute* div_attr)
> {
>   return div_attr->int_value() == 1;
> }
> 
10753,10772c10807,10828
< 	case elfcpp::Tag_DIV_use:
< 	  // This tag is set to zero if we can use UDIV and SDIV in Thumb
< 	  // mode on a v7-M or v7-R CPU; to one if we can not use UDIV or
< 	  // SDIV at all; and to two if we can use UDIV or SDIV on a v7-A
< 	  // CPU.  We will merge as follows: If the input attribute's value
< 	  // is one then the output attribute's value remains unchanged.  If
< 	  // the input attribute's value is zero or two then if the output
< 	  // attribute's value is one the output value is set to the input
< 	  // value, otherwise the output value must be the same as the
< 	  // inputs.  */
< 	  if (in_attr[i].int_value() != 1 && out_attr[i].int_value() != 1)
< 	    {
< 	      if (in_attr[i].int_value() != out_attr[i].int_value())
< 		{
< 		  gold_error(_("DIV usage mismatch between %s and output"),
< 			     name);
< 		}
< 	    }
< 
< 	  if (in_attr[i].int_value() != 1)
---
> 	case elfcpp::Tag_DIV_use: {
> 	  // A value of zero on input means that the divide instruction may
> 	  // be used if available in the base architecture as specified via
> 	  // Tag_CPU_arch and Tag_CPU_arch_profile.  A value of 1 means that
> 	  // the user did not want divide instructions.  A value of 2
> 	  // explicitly means that divide instructions were allowed in ARM
> 	  // and Thumb state.
> 	  int arch = this->
> 		get_aeabi_object_attribute(elfcpp::Tag_CPU_arch)->
> 		int_value();
> 	  int profile = this->
> 		get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile)->
> 		int_value();
> 	  if (in_attr[i].int_value() == out_attr[i].int_value())
> 	    /* Do nothing. */ ;
> 	  else if (attributes_forbid_div(&in_attr[i])
> 		   && !attributes_accept_div(arch, profile, &out_attr[i])) 
> 	    out_attr[i].set_int_value(1);
> 	  else if (attributes_forbid_div(&out_attr[i])
> 		   && attributes_accept_div(arch, profile, &in_attr[i]))
> 	    out_attr[i].set_int_value(in_attr[i].int_value());
> 	  else if (in_attr[i].int_value() == 2)
10774d10829
< 
10775a10831
>         }