chore: add migration/ bundle for cross-machine setup
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>
This commit is contained in:
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migration/project-root/ppc-manual/vmx/vminfp.md
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migration/project-root/ppc-manual/vmx/vminfp.md
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# `vminfp` — Vector Minimum Floating Point
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> **Category:** [VMX (Altivec)](../categories/vmx.md) · **Form:** [VX](../forms/VX.md) · **Opcode:** `0x1000044a`
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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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| `vminfp` | `vminfp` | — | Vector Minimum Floating Point |
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| `vminfp128` | `vminfp128` | — | Vector128 Minimum Floating Point |
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## Syntax
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```asm
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vminfp [VD], [VA], [VB]
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vminfp128 [VD], [VA], [VB]
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```
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## Encoding
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### `vminfp` — form `VX`
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- **Opcode word:** `0x1000044a`
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- **Primary opcode (bits 0–5):** `4`
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- **Extended opcode:** `1098`
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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 (4) |
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| 6–10 | `VRT/VD` | destination vector register |
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| 11–15 | `VRA/VA` | source A vector register |
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| 16–20 | `VRB/VB` | source B vector register |
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| 21–31 | `XO` | extended opcode (11 bits) |
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### `vminfp128` — form `VX128`
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- **Opcode word:** `0x180002c0`
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- **Primary opcode (bits 0–5):** `6`
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- **Extended opcode:** `704`
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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 (4 or 5) |
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| 6–10 | `VD128l` | destination low 5 bits |
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| 11–15 | `VA128l` | source A low 5 bits |
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| 16–20 | `VB128l` | source B low 5 bits |
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| 21 | `VA128H` | source A high bit |
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| 22 | `—` | reserved |
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| 23–25 | `VC` | optional VC / XO sub-field |
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| 26 | `VA128h` | source A middle bit |
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| 27 | `—` | reserved |
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| 28–29 | `VD128h` | destination high 2 bits |
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| 30–31 | `VB128h` | source B high 2 bits |
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## Operands
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| Field | Role | Description |
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| --- | --- | --- |
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| `VA` | vminfp: read; vminfp128: read | Source A vector register. |
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| `VB` | vminfp: read; vminfp128: read | Source B vector register. |
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| `VD` | vminfp: write; vminfp128: write | Destination vector register. |
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## Register Effects
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### `vminfp`
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- **Reads (always):** `VA`, `VB`
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- **Reads (conditional):** _none_
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- **Writes (always):** `VD`
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- **Writes (conditional):** _none_
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### `vminfp128`
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- **Reads (always):** `VA`, `VB`
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- **Reads (conditional):** _none_
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- **Writes (always):** `VD`
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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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**`vminfp`**
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- xenia-canary XML: [`tools/ppc-instructions.xml` — search for `mnem="vminfp"`](../../xenia-canary/tools/ppc-instructions.xml)
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- xenia-canary emit: [`src/xenia/cpu/ppc/ppc_emit_altivec.cc:899`](../../xenia-canary/src/xenia/cpu/ppc/ppc_emit_altivec.cc#L899)
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- xenia-rs opcode: [`crates/xenia-cpu/src/opcode.rs:103`](../../xenia-rs/crates/xenia-cpu/src/opcode.rs#L103)
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- xenia-rs decoder: [`crates/xenia-cpu/src/decoder.rs:527`](../../xenia-rs/crates/xenia-cpu/src/decoder.rs#L527)
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- xenia-rs interpreter: [`crates/xenia-cpu/src/interpreter.rs:2137-2144`](../../xenia-rs/crates/xenia-cpu/src/interpreter.rs#L2137-L2144)
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<details><summary>xenia-rs interpreter body (frozen snapshot)</summary>
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```rust
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PpcOpcode::vminfp => {
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let a = ctx.vr[instr.ra()].as_f32x4();
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let b = ctx.vr[instr.rb()].as_f32x4();
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let mut r = [0f32; 4];
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for i in 0..4 { r[i] = vmx::min_nan(a[i], b[i]); }
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ctx.vr[instr.rd()] = xenia_types::Vec128::from_f32x4_array(r);
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ctx.pc += 4;
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}
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```
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</details>
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**`vminfp128`**
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- xenia-canary XML: [`tools/ppc-instructions.xml` — search for `mnem="vminfp128"`](../../xenia-canary/tools/ppc-instructions.xml)
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- xenia-canary emit: [`src/xenia/cpu/ppc/ppc_emit_altivec.cc:902`](../../xenia-canary/src/xenia/cpu/ppc/ppc_emit_altivec.cc#L902)
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- xenia-rs opcode: [`crates/xenia-cpu/src/opcode.rs:103`](../../xenia-rs/crates/xenia-cpu/src/opcode.rs#L103)
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- xenia-rs decoder: [`crates/xenia-cpu/src/decoder.rs:697`](../../xenia-rs/crates/xenia-cpu/src/decoder.rs#L697)
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- xenia-rs interpreter: [`crates/xenia-cpu/src/interpreter.rs:2145-2152`](../../xenia-rs/crates/xenia-cpu/src/interpreter.rs#L2145-L2152)
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<details><summary>xenia-rs interpreter body (frozen snapshot)</summary>
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```rust
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PpcOpcode::vminfp128 => {
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let a = ctx.vr[instr.va128()].as_f32x4();
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let b = ctx.vr[instr.vb128()].as_f32x4();
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let mut r = [0f32; 4];
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for i in 0..4 { r[i] = vmx::min_nan(a[i], b[i]); }
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ctx.vr[instr.vd128()] = xenia_types::Vec128::from_f32x4_array(r);
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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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- **Per-lane IEEE min.** Four word lanes; `VD[i] = (VA[i] < VB[i]) ? VA[i] : VB[i]`.
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- **NaN propagation surprise.** Xenia uses `if a < b { a } else { b }`, so any NaN comparison evaluates false and the result is `VB`. The IBM manual specifies NaN-propagating min — i.e. NaN inputs should yield NaN. Hardware's `vminfp(NaN, x) = NaN` while xenia returns `x`. **Worth checking against `vmx.rs` for any future correctness fixes.**
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- **Sign of zero.** `vminfp(+0, -0)` returns `-0` in xenia (since `+0 < -0` is false → returns `b = -0`); hardware likely returns the negative zero too via the same comparator.
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- **`VSCR[NJ]` denormals.** With `NJ = 1` (Xenon default), denormal inputs are flushed to `±0` before comparison.
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- **No `VSCR[SAT]` change, no XER change, no exceptions.**
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- **Big-endian word lanes.** Lane 0 is the most-significant word.
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- **Aliasing legal.** `vminfp v3, v3, v4` clamps `v3` from above by `v4`.
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- **VMX128 sibling (`vminfp128`).** Identical comparator semantics with the extended encoding.
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## Related Instructions
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- [`vmaxfp`](vmaxfp.md) — the per-lane maximum.
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- [`vcmpgtfp`](vcmpgtfp.md), [`vcmpgefp`](vcmpgefp.md) — separate compare-and-mask path.
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- [`vsel`](vsel.md) — combine masks with arbitrary alternatives.
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- [`vmaddfp`](vmaddfp.md) — fused multiply-add when the min is part of a polynomial.
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- [`vminsw`](vminsw.md) — integer-word min if the lanes are signed integers.
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## IBM Reference
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- [AIX 7.3 — `vminfp` (Vector Minimum Floating Point)](https://www.ibm.com/docs/en/aix/7.3.0?topic=set-vminfp-vector-minimum-floating-point-instruction)
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- [IBM AltiVec Technology Programmer's Interface Manual, Chapter 5 — Floating-Point Min/Max](https://www.nxp.com/docs/en/reference-manual/ALTIVECPIM.pdf)
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