From ab64c0412bfe016294895060d6bf9b434d1c9517 Mon Sep 17 00:00:00 2001
From: jgrusewski <jgrusewski@localhost>
Date: Fri, 22 May 2026 20:34:59 +0200
Subject: [PATCH] chore(ml): migrate deprecated cudarc memcpy_* calls

cudarc 0.19 deprecated memcpy_stod (use clone_htod) and memcpy_dtov
(use clone_dtoh). Six call sites in cuda_pipeline/mod.rs migrated.
Pre-existing warnings surfaced now because the recent file-level
allow(unsafe_code) on this file no longer per-line-suppresses the
deprecated lint.

Per feedback_no_legacy_aliases: rename call sites directly, no
deprecated wrappers. Documented in dqn-wire-up-audit.md.
---
 crates/ml/src/cuda_pipeline/mod.rs | 12 ++++++------
 docs/dqn-wire-up-audit.md          | 16 ++++++++++++++++
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/crates/ml/src/cuda_pipeline/mod.rs b/crates/ml/src/cuda_pipeline/mod.rs
index 81d056314..cc5958881 100644
--- a/crates/ml/src/cuda_pipeline/mod.rs
+++ b/crates/ml/src/cuda_pipeline/mod.rs
@@ -1350,7 +1350,7 @@ mod tests {
         // q_values: uniform Q (zero) so direction is decided purely by C51
         // logits below; magnitude/order/urgency default to Boltzmann-uniform.
         let q_host = vec![0.0_f32; batch * q_stride];
-        let q_buf = stream.memcpy_stod(&q_host).expect("upload q_values");
+        let q_buf = stream.clone_htod(&q_host).expect("upload q_values");
 
         // C51 logits: per-direction peaked at atom corresponding to target v.
         // Linear support v_min=-1 v_max=+1 delta_z=0.1 → atom_v = -1 + a*0.1.
@@ -1370,7 +1370,7 @@ mod tests {
                 b_logits_host[base + peak_a] = 5.0_f32;
             }
         }
-        let b_logits_buf = stream.memcpy_stod(&b_logits_host).expect("upload logits");
+        let b_logits_buf = stream.clone_htod(&b_logits_host).expect("upload logits");
 
         // per_sample_support: [batch, b0, 3] stride-12 — every sample/direction
         // gets the same linear support [v_min, v_max, delta_z].
@@ -1383,7 +1383,7 @@ mod tests {
                 support_host[base + 2] = delta_z;
             }
         }
-        let support_buf = stream.memcpy_stod(&support_host).expect("upload support");
+        let support_buf = stream.clone_htod(&support_host).expect("upload support");
 
         // SP17 Commit C (2026-05-08): v_logits_dir [batch, n_atoms] — V-head
         // logits row required by the Thompson direction selector. Required
@@ -1397,7 +1397,7 @@ mod tests {
         // pre-SP17). Without this buffer the kernel reads stale stack
         // memory for v_logits_dir → SIGSEGV.
         let v_logits_host = vec![0.0_f32; batch * (n_atoms as usize)];
-        let v_logits_buf = stream.memcpy_stod(&v_logits_host).expect("upload v_logits");
+        let v_logits_buf = stream.clone_htod(&v_logits_host).expect("upload v_logits");
 
         // SP10: ISV buffer with EVAL_THOMPSON_TEMP_INDEX set to 1.0
         // (pure Thompson). All other slots zero — kernel only reads
@@ -1405,7 +1405,7 @@ mod tests {
         // block reads ISV[16]/[21] with cold-start fallback.
         let mut isv_host = vec![0.0_f32; ISV_TOTAL_DIM];
         isv_host[EVAL_THOMPSON_TEMP_INDEX] = 1.0;
-        let isv_buf = stream.memcpy_stod(&isv_host).expect("upload isv");
+        let isv_buf = stream.clone_htod(&isv_host).expect("upload isv");
 
         let mut actions_buf = stream.alloc_zeros::<i32>(batch).expect("alloc actions");
         let mut q_gaps_buf = stream.alloc_zeros::<f32>(batch).expect("alloc q_gaps");
@@ -1463,7 +1463,7 @@ mod tests {
         }
         stream.synchronize().expect("sync");
 
-        let host_actions = stream.memcpy_dtov(&actions_buf).expect("readback actions");
+        let host_actions = stream.clone_dtoh(&actions_buf).expect("readback actions");
         let mut dir_hist = [0_u32; 4];
         for &a in &host_actions {
             let dir = (a / (b1 * b2 * b3)) as usize;
diff --git a/docs/dqn-wire-up-audit.md b/docs/dqn-wire-up-audit.md
index 7040f9be9..1cdeeb2c8 100644
--- a/docs/dqn-wire-up-audit.md
+++ b/docs/dqn-wire-up-audit.md
@@ -18776,3 +18776,19 @@ same justification comment: `crates/ml/examples/alpha_dqn_h600_smoke.rs`,
 `crates/ml/tests/smoke_test_real_data.rs`.
 
 **Wire-up impact:** None (lint hygiene only — no semantic changes).
+
+## 2026-05-22 — chore(ml): migrate deprecated cudarc memcpy_* calls
+
+**Branch:** `ml-alpha-phase-a`. **Trigger:** cudarc 0.19 deprecated
+`CudaStream::memcpy_stod` (use `clone_htod`) and `CudaStream::memcpy_dtov`
+(use `clone_dtoh`). Pre-existing warnings became visible after the
+file-level `#![allow(unsafe_code)]` was added (it suppresses unsafe-block
+noise but not the `deprecated` lint).
+
+**Change:** `crates/ml/src/cuda_pipeline/mod.rs` — 5 `memcpy_stod` →
+`clone_htod` (lines 1353, 1373, 1386, 1400, 1408) and 1 `memcpy_dtov` →
+`clone_dtoh` (line 1466). Same FFI semantics, just current cudarc API
+names. Per `feedback_no_legacy_aliases`: rename call sites directly, no
+deprecated wrappers retained.
+
+**Wire-up impact:** None (API surface unchanged; FFI semantics identical).