e6d43a23ac
Bundles state that lives OUTSIDE the xenia-rs repo so a fresh clone on
another machine can be brought up to identical configuration via
migration/setup.sh:
- claude-memory/ ~/.claude/projects/-home-fabi-RE-Project-Sylpheed/memory/
(103 files, 1.1 MB - MEMORY.md + every
project_xenia_rs_*.md from audits
addis_signext through audit-058)
- project-root/dot-claude/ <project-root>/.claude/settings.json
(Stop hook + permissions)
- project-root/ppc-manual/ <project-root>/ppc-manual/
(PowerPC reference docs, 397 files, 3.7 MB)
- project-root/run-canary.sh <project-root>/run-canary.sh
- README.md Human-readable setup checklist
- setup.sh Idempotent installer (also reclones
xenia-canary at pinned HEAD 6de80dffe)
- MANIFEST.md Per-file mapping + per-file-not-bundled
restoration recipe
Excluded from bundle (not shippable via git):
- Sylpheed ISO (7.8 GB; copyright; manual copy required)
- sylpheed.db (395 MB; regenerable from XEX via analysis tooling)
- target/ build artifacts (rebuild on target)
- audit-runs probe firehoses (.log/.stdout/.stderr ~11 GB; rerun if needed)
- audit-runs memory dumps (.bin ~4.5 GB; rerun audit-026/027/029 if needed)
- xenia-canary checkout (setup.sh reclones from
git.mc02.dev/fabi/Xenia-Canary.git at HEAD 6de80dffe)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
116 lines
4.1 KiB
Markdown
116 lines
4.1 KiB
Markdown
# `xori` — XOR Immediate
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> **Category:** [Integer ALU](../categories/alu.md) · **Form:** [D](../forms/D.md) · **Opcode:** `0x68000000`
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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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| `xori` | `xori` | — | XOR Immediate |
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## Syntax
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```asm
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xori [RA], [RS], [UIMM]
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```
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## Encoding
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### `xori` — form `D`
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- **Opcode word:** `0x68000000`
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- **Primary opcode (bits 0–5):** `26`
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- **Extended opcode:** —
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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 |
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| 6–10 | `RT` | destination GPR (or RS when storing) |
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| 11–15 | `RA` | source GPR (0 ⇒ literal 0 for RA0 forms) |
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| 16–31 | `D/SI/UI` | 16-bit signed or unsigned immediate |
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## Operands
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| Field | Role | Description |
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| --- | --- | --- |
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| `RS` | xori: read | Source GPR (alias for RD in some stores). |
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| `UIMM` | xori: read | 16-bit unsigned immediate. Zero-extended. |
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| `RA` | xori: write | Source GPR (`r0`–`r31`). |
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## Register Effects
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### `xori`
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- **Reads (always):** `RS`, `UIMM`
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- **Reads (conditional):** _none_
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- **Writes (always):** `RA`
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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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RA <- (RS) ^ (0x0000 || UIMM)
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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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**`xori`**
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- xenia-canary XML: [`tools/ppc-instructions.xml` — search for `mnem="xori"`](../../xenia-canary/tools/ppc-instructions.xml)
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- xenia-canary emit: [`src/xenia/cpu/ppc/ppc_emit_alu.cc:839`](../../xenia-canary/src/xenia/cpu/ppc/ppc_emit_alu.cc#L839)
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- xenia-rs opcode: [`crates/xenia-cpu/src/opcode.rs:132`](../../xenia-rs/crates/xenia-cpu/src/opcode.rs#L132)
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- xenia-rs decoder: [`crates/xenia-cpu/src/decoder.rs:349`](../../xenia-rs/crates/xenia-cpu/src/decoder.rs#L349)
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- xenia-rs interpreter: [`crates/xenia-cpu/src/interpreter.rs:520-523`](../../xenia-rs/crates/xenia-cpu/src/interpreter.rs#L520-L523)
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<details><summary>xenia-rs interpreter body (frozen snapshot)</summary>
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```rust
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PpcOpcode::xori => {
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ctx.gpr[instr.ra()] = ctx.gpr[instr.rs()] ^ (instr.uimm16() as u64);
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ctx.pc += 4;
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}
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```
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</details>
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<!-- GENERATED: END -->
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## Special Cases & Edge Conditions
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- **No record form.** Like [`ori`](ori.md), there is no `xori.`. To get a CR0 update follow with `cmpwi` or use [`xorx`](xorx.md) with `Rc=1`.
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- **Immediate is zero-extended** to 64 bits. Only the low 16 bits of `RA` can be flipped; the high 48 bits are passed through from `RS` unchanged.
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- **`xori 0, 0, 0` is a valid NOP encoding** but the canonical NOP is `ori 0, 0, 0`. Disassemblers should still display this as `xori r0, r0, 0` or recognise it as a no-op.
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- **64-bit operation in xenia-rs.** [`interpreter.rs:338`](../../xenia-rs/crates/xenia-cpu/src/interpreter.rs#L338) — full `u64` XOR with the immediate.
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- **No `XER`, no `CR`** side effects.
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- **`RA = 0` reads `r0`** (not literal zero); see [`ori`](ori.md).
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- **Useful for masked toggle.** `xori rA, rS, mask` flips the bits of `rS` indicated by `mask` (low 16 bits only).
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## Related Instructions
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- [`xoris`](xoris.md) — companion (immediate shifted left 16).
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- [`xorx`](xorx.md) — register-register XOR.
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- [`eqvx`](eqvx.md) — `~(RS ^ RB)`.
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- [`ori`](ori.md), [`andix`](andix.md) — sister immediate logicals.
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## IBM Reference
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- [AIX 7.3 — `xori` (XOR Immediate)](https://www.ibm.com/docs/en/aix/7.3.0?topic=set-xori-immediate-instruction)
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