Latest version of native ppc assembler for G4 Macintosh

[Tinkerer Atlarge]

"dis.of" the Open Firmware assembler/disassembler package continues to
evolve. More options have been added including:

- now has own namespace to avoid cluttering user dictionary

- BI and BO fields now decoded for simpler branch instructions

- forth names in label+offset format now available as branch targets

- mtspr and mfspr now recognize register names as well as numbers

'asm' makes it easy to try out individual ppc instructions at the Open
Firmware prompt.

eg extlwi "Extract & left-justify n bits, starting bit b":

( boot hd:3,\dis.of )
code trythat
asm extlwi r20,r20,8,16 \ r20 = top item forth parameter stack
c;

56789abc trythat . ( response -> 9a000000 )

code trythis
asm lwz r21,0(r31) \ r21 = spare reg, (r31) -> 2nd-on-stack
asm addi r31,r31,4 \ adj r31 stack ptr (nip 2nd fm stack)
asm inslwi r20,r21,16,8 \ insert lhs 16 bits of r21 at r20[8]
c;

12345678 cccccccc trythis . ( response -> cc1234cc )

Alternatively, '<address> azm' may be used to patch previously installed
code.

"dis.of" has been donated to the public domain but has grown too large
to post on usenet. 160K as of 14-Dec-2010.

Copies of this latest version are available from tinkerer at the above
email address.