10dc260f0c
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>
126 lines
4.9 KiB
Markdown
126 lines
4.9 KiB
Markdown
# `cror` — Condition Register OR
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> **Category:** [Control / CR / SPR](../categories/control.md) · **Form:** [XL](../forms/XL.md) · **Opcode:** `0x4c000382`
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<!-- GENERATED: BEGIN -->
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## Assembler Mnemonics
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| Mnemonic | XML entry | Flags | Description |
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| --- | --- | --- | --- |
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| `cror` | `cror` | — | Condition Register OR |
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## Syntax
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```asm
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cror [CRBD], [CRBA], [CRBB]
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```
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## Encoding
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### `cror` — form `XL`
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- **Opcode word:** `0x4c000382`
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- **Primary opcode (bits 0–5):** `19`
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- **Extended opcode:** `449`
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- **Synchronising:** no
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| Bits | Field | Meaning |
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| --- | --- | --- |
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| 0–5 | `OPCD` | primary opcode (19) |
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| 6–10 | `BT/BO` | target / branch options |
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| 11–15 | `BA/BI` | source A / CR bit to test |
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| 16–20 | `BB` | source B |
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| 21–30 | `XO` | extended opcode (10 bits) |
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| 31 | `LK` | link flag |
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## Operands
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| Field | Role | Description |
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| --- | --- | --- |
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| `CRBA` | cror: read | CR source bit A (0–31). |
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| `CRBB` | cror: read | CR source bit B (0–31). |
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| `CRBD` | cror: write | CR destination bit (0–31). |
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## Register Effects
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### `cror`
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- **Reads (always):** `CRBA`, `CRBB`
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- **Reads (conditional):** _none_
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- **Writes (always):** `CRBD`
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- **Writes (conditional):** _none_
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## Status-Register Effects
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_No condition-register or status-register effects._
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## Operation (pseudocode)
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```
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; Pseudocode derives directly from the xenia-rs interpreter
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; arm (see Implementation References). Operation semantics:
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; - Read source operands from the fields listed under Operands.
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; - Apply the arithmetic / logical / memory action described
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; in the Description field above.
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; - Write results to the destination register(s); update any
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; status bits enumerated under Status-Register Effects.
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; Consult the IBM AIX reference link under IBM Reference for
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; canonical PPC-style pseudocode where xenia's expression is
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; terse.
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```
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## C Translation Example
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```c
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/* C translation: the xenia-rs interpreter arm below in */
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/* Implementation References is the authoritative semantic */
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/* snapshot. Translate it line-by-line: */
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/* - ctx.gpr[N] -> r[N] (or f[]/v[] for FPRs/VRs) */
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/* - mem.read_u*/write_u* -> mem_read_u*_be / mem_write_u*_be */
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/* - ctx.update_cr_signed(fld, v) -> update_cr_signed(fld, v) */
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/* - ctx.xer_ca / xer_ov / xer_so -> xer.CA / xer.OV / xer.SO */
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/* The Register Effects and Status-Register Effects tables above */
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/* enumerate every side effect a faithful translation must emit. */
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```
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## Implementation References
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**`cror`**
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- xenia-canary XML: [`tools/ppc-instructions.xml` — search for `mnem="cror"`](../../xenia-canary/tools/ppc-instructions.xml)
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- xenia-canary emit: [`src/xenia/cpu/ppc/ppc_emit_control.cc:397`](../../xenia-canary/src/xenia/cpu/ppc/ppc_emit_control.cc#L397)
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- xenia-rs opcode: [`crates/xenia-cpu/src/opcode.rs:17`](../../xenia-rs/crates/xenia-cpu/src/opcode.rs#L17)
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- xenia-rs decoder: [`crates/xenia-cpu/src/decoder.rs:720`](../../xenia-rs/crates/xenia-cpu/src/decoder.rs#L720)
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<!-- GENERATED: END -->
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## Special Cases & Edge Conditions
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- **Operation.** `CR[CRBD] ← CR[CRBA] OR CR[CRBB]`. All other CR bits are preserved.
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- **`crmove BT, BA` idiom.** With `BA == BB`, `cror BT, BA, BA` is the canonical PowerPC **single-bit copy** between CR bits, recognised by assemblers as the simplified mnemonic `crmove BT, BA`. This is the standard way to relocate a CR bit (e.g., promote `cr1.EQ` to `cr0.EQ` so a default-`cr0` branch can consume it).
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- **Bit-level operands.** Three independent 5-bit CR-bit indices; mixing CR fields is the whole point of this family.
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- **Use case.** Branch on "A OR B" of two prior compare results — saves an extra branch by collapsing two conditions.
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- **No `Rc` / `OE`.** Pure CR-bit dataflow.
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- **Not synchronising.** Reorderable.
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- **xenia status.** Most-used CR-logical instruction in real code (almost always as `crmove`). Decoded by the generic XL-form CR-logical handler; canary emits a host OR.
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## Related Instructions
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- [`crand`](crand.md), [`crandc`](crandc.md) — AND family.
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- [`crorc`](crorc.md) — OR with complement.
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- [`crnor`](crnor.md), [`crnand`](crnand.md) — negated forms.
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- [`crxor`](crxor.md), [`creqv`](creqv.md) — XOR / XNOR.
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- [`mcrf`](mcrf.md) — copy a 4-bit CR field wholesale.
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- [`bcx`](../branch/bcx.md), [`bclrx`](../branch/bclrx.md), [`bcctrx`](../branch/bcctrx.md) — typical consumers.
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### Simplified Mnemonics
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| Simplified | Expansion | Effect |
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| --- | --- | --- |
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| `crmove BT, BA` | `cror BT, BA, BA` | `CR[BT] ← CR[BA]` (single-bit copy) |
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## IBM Reference
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- [AIX 7.3 — `cror` (Condition Register OR)](https://www.ibm.com/docs/en/aix/7.3.0?topic=set-cror-condition-register-instruction)
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- [AIX 7.3 — Condition register simplified mnemonics](https://www.ibm.com/docs/en/aix/7.3.0?topic=mnemonics-condition-register-logical-simplified)
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