Add MI355X config: qwen3.5-fp4-sglang-mtp

Adds the qwen3.5-fp4-mi355x-sglang-mtp recipe using the latest
sglang-rocm nightly v0.5.12-rocm720-mi35x-20260517 (matches PRs
#1440-1444 which bump other mi355x recipes to the same image).

Replaces the stale #1078 which targeted v0.5.10rc0-rocm700-mi35x-20260417
and was tagged broken; that branch reverted unrelated merged changes
when rebased.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: functionstackx

.github/configs/amd-master.yaml

@@ -367,6 +367,26 @@ qwen3.5-fp4-mi355x-atom:
       - { tp: 2, conc-start: 4, conc-end: 256 }
       - { tp: 4, conc-start: 4, conc-end: 16 }
 
+qwen3.5-fp4-mi355x-sglang-mtp:
+  image: lmsysorg/sglang-rocm:v0.5.12-rocm720-mi35x-20260517
+  model: amd/Qwen3.5-397B-A17B-MXFP4
+  model-prefix: qwen3.5
+  runner: mi355x
+  precision: fp4
+  framework: sglang
+  multinode: false
+  seq-len-configs:
+  - isl: 1024
+    osl: 1024
+    search-space:
+    - { tp: 2, conc-start: 4, conc-end: 256, spec-decoding: mtp }
+    - { tp: 4, conc-start: 4, conc-end: 16, spec-decoding: mtp }
+  - isl: 8192
+    osl: 1024
+    search-space:
+    - { tp: 2, conc-start: 4, conc-end: 256, spec-decoding: mtp }
+    - { tp: 4, conc-start: 4, conc-end: 16, spec-decoding: mtp }
+
 qwen3.5-fp8-mi300x-sglang:
   image: lmsysorg/sglang:v0.5.10-rocm720-mi30x
   model: Qwen/Qwen3.5-397B-A17B-FP8

perf-changelog.yaml

@@ -2629,3 +2629,9 @@
   description:
     - "Update vLLM ROCm image from v0.18.0 to v0.21.0"
   pr-link: https://github.com/SemiAnalysisAI/InferenceX/pull/1404
+
+- config-keys:
+    - qwen3.5-fp4-mi355x-sglang-mtp
+  description:
+    - "Add MI355X config: qwen3.5-fp4-sglang-mtp using lmsysorg/sglang-rocm:v0.5.12-rocm720-mi35x-20260517"
+  pr-link: PLACEHOLDER