PowerPC Instructions

PowerPC Instructions

[Joel Sherrill]

Hi,

I have a user submitted port of RTEMS to the PowerPC (IBM 403) and it uses
some instructions (or alternate names) he added to his local gas.  I am
using binutils 2.6 configured for powerpc-elf.  I know of the following
based on the error messages: 

/usr1/tmp/cca004pL.s: Assembler messages:
/usr1/tmp/cca004pL.s:54: Error: Unrecognized opcode: `mtsprg3'
/usr1/tmp/cca004pL.s:56: Error: Unrecognized opcode: `mtsprg2'
/usr1/tmp/cca004pL.s:131: Error: Unrecognized opcode: `mtexier'
/usr1/tmp/cca004pL.s:137: Error: Unrecognized opcode: `mttsr'
/usr1/tmp/cca004pL.s:143: Error: Unrecognized opcode: `mttsr'

I am not a PowerPC expert by any definition. (OK I do own a few PowerPC 
manuals :).)   What is the best thing for me to do?  I see two options:

1.  Merge his patches.

2.  If possible, change the instruction names to standard ones.

+----------------------------------------+--------------------------------+
| Joel Sherrill                          | Sr. Computer Scientist         |
| joel@merlin.gcs.redstone.army.mil      | On-Line Applications Research  |
| Ask me about RTEMS: a free real-time   | Huntsville AL 35805            |
|   multiprocessor executive!            | (205) 883-0131                 |
+----------------------------------------+--------------------------------+

Re: PowerPC Instructions

[Ian Lance Taylor]

   Date: Fri, 1 Dec 1995 15:19:15 -0600 (CST)
   From: Joel Sherrill <joel@merlin.gcs.redstone.army.mil>

   I have a user submitted port of RTEMS to the PowerPC (IBM 403) and it uses
   some instructions (or alternate names) he added to his local gas.  I am
   using binutils 2.6 configured for powerpc-elf.  I know of the following
   based on the error messages: 

   /usr1/tmp/cca004pL.s: Assembler messages:
   /usr1/tmp/cca004pL.s:54: Error: Unrecognized opcode: `mtsprg3'
   /usr1/tmp/cca004pL.s:56: Error: Unrecognized opcode: `mtsprg2'
   /usr1/tmp/cca004pL.s:131: Error: Unrecognized opcode: `mtexier'
   /usr1/tmp/cca004pL.s:137: Error: Unrecognized opcode: `mttsr'
   /usr1/tmp/cca004pL.s:143: Error: Unrecognized opcode: `mttsr'

These are all ``move to special register'' instructions.  If you can
find out the appropriate special register number, it should be
possible to replace them all with the mtspr instruction.

Incidentally, gas already supports mtsprg with two operands.  I don't
know what the other two are.

If these are standard instructions for the 403, then you should patch
opcodes/ppc-opc.c and send in the patch.  Look for mtmq to see the
mtspr variants.

Ian