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chore(tools): adopt the PPC manual and a canary launcher that works anywhere
CONSOLIDATION.md Phase 6. Both lived untracked in the project root -- on one
disk, backed up by nothing.

  tools/ppc-manual/   393 files, 3.7 MB. 455 instructions, 350 family pages,
                      598 mnemonics resolvable through index.json, plus the
                      generator that produced them.
  tools/run-canary.sh the oracle launcher.

🔴 THE LAUNCHER WAS BROKEN IN TWO WAYS AND IS REWRITTEN, not copied:

  * it pointed at `xenia-rs/sylpheed.iso`, a SYMLINK. Wine cannot resolve one
    and says "path invalid", which reads as a corrupt image rather than a path
    problem -- it has cost a session before. It now points at the real file and
    warns if handed a symlink.
  * it hardcoded one machine's absolute paths, and named `xenia-rs`, which this
    consolidation retires. Now derived from the script's own location, with
    SYLPH_CANARY_BIN / SYLPH_ISO overrides and a check that each exists.

The standing constraints are in its header where someone will read them: one
emulator at a time, Canary runs MUTED, and never judge a crash or a hang from
a Bash-launched run -- a SIGKILL that looked like the binary was the editor's
process supervisor.

⚠️ The manual's GENERATOR reads the xenia-rs source tree, which is going away.
Its decoder now lives here as crates/sylpheed-ppc, so the generator must be
repointed before it is run again. Recorded in the README rather than left for
someone to discover; the manual's content is checked in and regenerates from
nothing implicitly.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-13 21:18:00 +02:00

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crnor — Condition Register NOR

Category: Control / CR / SPR · Form: XL · Opcode: 0x4c000042

Assembler Mnemonics

Mnemonic XML entry Flags Description
crnor crnor Condition Register NOR

Syntax

crnor [CRBD], [CRBA], [CRBB]

Encoding

crnor — form XL

  • Opcode word: 0x4c000042
  • Primary opcode (bits 05): 19
  • Extended opcode: 33
  • Synchronising: no
Bits Field Meaning
05 OPCD primary opcode (19)
610 BT/BO target / branch options
1115 BA/BI source A / CR bit to test
1620 BB source B
2130 XO extended opcode (10 bits)
31 LK link flag

Operands

Field Role Description
CRBA crnor: read CR source bit A (031).
CRBB crnor: read CR source bit B (031).
CRBD crnor: write CR destination bit (031).

Register Effects

crnor

  • Reads (always): CRBA, CRBB
  • Reads (conditional): none
  • Writes (always): CRBD
  • Writes (conditional): none

Status-Register Effects

No condition-register or status-register effects.

Operation (pseudocode)

; Pseudocode derives directly from the xenia-rs interpreter
; arm (see Implementation References). Operation semantics:
;   - Read source operands from the fields listed under Operands.
;   - Apply the arithmetic / logical / memory action described
;     in the Description field above.
;   - Write results to the destination register(s); update any
;     status bits enumerated under Status-Register Effects.
; Consult the IBM AIX reference link under IBM Reference for
; canonical PPC-style pseudocode where xenia's expression is
; terse.

C Translation Example

/* C translation: the xenia-rs interpreter arm below in           */
/* Implementation References is the authoritative semantic        */
/* snapshot. Translate it line-by-line:                            */
/*   - ctx.gpr[N]  -> r[N]       (or f[]/v[] for FPRs/VRs)        */
/*   - mem.read_u*/write_u* -> mem_read_u*_be / mem_write_u*_be   */
/*   - ctx.update_cr_signed(fld, v) -> update_cr_signed(fld, v)   */
/*   - ctx.xer_ca / xer_ov / xer_so -> xer.CA / xer.OV / xer.SO   */
/* The Register Effects and Status-Register Effects tables above  */
/* enumerate every side effect a faithful translation must emit.  */

Implementation References

crnor

Special Cases & Edge Conditions

  • Operation. CR[CRBD] ← ¬(CR[CRBA] OR CR[CRBB]). Result is 1 only when both source bits are 0; otherwise 0.
  • crnot BT, BA idiom. With BA == BB, crnor BT, BA, BA¬CR[BA] — this is the canonical PowerPC single-bit invert, recognised by assemblers as the simplified mnemonic crnot BT, BA.
  • Bit-level operands. 5-bit absolute CR-bit indices (0..31). The three bits may live in any combination of the eight CR fields.
  • Use case. Branch on "neither A nor B"; or, with crnot, simply complement a CR bit before consuming it in a bcx.
  • No Rc / OE. Pure CR-bit dataflow; CR0/XER untouched.
  • Not synchronising. Reorderable.
  • xenia status. Decoded via the generic CR-logical handler. xenia-canary's InstrEmit_crnor emits a host OR followed by NOT.
  • cror, crorc — non-negated OR siblings.
  • crnand — negated AND (the De Morgan dual).
  • crand, crandc — AND family.
  • crxor, creqv — XOR / XNOR.
  • mcrf — bulk CR-field copy.
  • bcx — typical consumer of synthesised CR bits.

Simplified Mnemonics

Simplified Expansion Effect
crnot BT, BA crnor BT, BA, BA CR[BT] ← ¬CR[BA] (invert single bit)

IBM Reference