RELEASE NOTES
=============

Product   : GNU C Compiler Toolkit for ARC Processors
MileStone : First support release of the upgraded toolchain
Version   : GNU binutils 2.15 codito-20050725-release
	    GCC 3.4.4 codito 20050725 [ derived from FSF snapshot on 26th Jan 
	    2005 ]
Date      : July 25 2005

Table of Contents
-----------------

1.  Overview
2.  Features Supported
3.  Major changes in this release
4.  Known Limitations and Defects
5.  Contact Information
6.  Reference 


1.  Overview
------------
    This is the first support release of the upgraded GNU Tools for the ARC, 
    consisting of feature enhancements, clean-ups and bug-fixes.

2.  Features Supported
----------------------

    2.1 Features of support release #1 (July 25 2005)
    -------------------------------------------------
    * Handling of extension instructions in the binutils rewritten.
    * New flags added to the compiler and binutils (See section 3 below).
    * Bug #1366 in the generation of min instructions fixed.
    * Bug #1307 in the generation of multiple shifts for ARCtangent-A4 fixed.
    * Bug #1378 in the costs of multiply instructions fixed.
    * Bug #1310 with generation of bbit instructions fixed.
    * Bug #1301 with spurious add2 generation in A4 code fixed.
    * Bugs #1284, #1294 fixed, allowing brk generation with builtins for all	
      cores.
    * Bug #1011 with bic instruction generation fixed.
    * Bug #1293 fixed, disallowing generation of divaw instruction generation
      and support for the same in binutils, for ARC700 base case.  
    * Bug #1309 with the support for lsl instructions in the assembler fixed.
    * Miscellaneous code clean-ups.    

    2.2 Features of the first upgrade release (May 23 2005)
    -------------------------------------------------------
    * Improved ABI compatibility
    * Support for extension instructions for ARCtangent-A5, ARC600 and ARC700 
      processors
    * Support for builtins (compiler intrinsics) as an interface for generating
      assembly instructions.
    * Better support for DWARF-2 debug information generation.
    * newlib is now built for big-endian targets as well.
    * Numerous bug-fixes and cleanups.

3. Major back-end changes in this release
-----------------------------------------
	* The handling of extension instructions has been rewritten. Now, the 
    extension instructions are read in by the assembler at run-time from the file
    arcextlib.s installed at $INSTALLPREFIX/extlib/. The user can therefore, change
    the definitions of the extension instructions and registers and the tools 
    dynamically understand the changes and generate the appropriate code.

	* Using extension core registers requires the .extRegister directive in 
   the assembler sources. 

	* The assembler no longer understands the extension instructions for
    any architecture variants by default, and gives out an error messsage. The
    appropriate command-line switches have been added to the assembler for the 
    same (ref. ARC GNU Tools Reference Manual). e.g. For using the norm instruction
    in ARCtangent-A5 assembly code, the switch -mnorm needs to be passed to gas.
        
	* The compiler and assembler assume the ARC700 multiplier extension to be 
    present by default. To disable the instruction, the command-line switch 
    -mno-mpy needs to be passed.
   
        * The ARC700 mpylo and mpyhi mnemonics are no longer supported. Instead use the mnemonics
     mpy and mpyh for the same purpose. This change is to bring the tools in line with the 
     ARCompact ISA programmers guide. (Building the linux kernel for ARC700 requires 
     a small change in delay.h which is available as a separate patch set.)

	* The following command-line switches have been added:

	a) Compiler switches:
	   + -mno-mpy
	   + -mEA
	   + -mmin_max

	b) Assembler switches
	   + -mnorm
	   + -mswap
	   + -mmul64
	   + -mEA
	   + -mmin_max
	   + -mbarrel_shifter
	   + -mno-mpy

	NOTE: When given to the compiler driver (i.e. arc-elf32-gcc), these
	      switches get passed to the assembler, and therefore need not be 
	      specified separately on the command-line as assembler switches 
	      also.
	      i.e. Adding -Wa,-mnorm to the command arc-elf32-gcc -mnorm ...
	      is redundant.

	For further details about these flags, please refer to the ARC GNU Tools
    Reference Manual provided with this release.

	For the list of changes since the GCC-2.95.3 based release, see the release
    notes for the first release of the upgraded toolchain.

4. Known Limitations and Defects
--------------------------------
    * Position Independent Code generation support is only available for the 
      ARC700 processor.

5. Contact Information  
----------------------
   In case of any defects please contact arc-support@codito.com.
   If you have a support contract, please use the support site at 
   http://support.codito.com.
 
6. References
-------------
    * ARC700 ISA Reference Manual
    * ARC GNU Tools User Guide
    * Sys V ABI Extension for ELF for the ARC


Tools Team 
Codito Technologies