From cdc48da9cdf63a11d8b28ebb47b06895fae97dcc Mon Sep 17 00:00:00 2001
From: nimlgen <138685161+nimlgen@users.noreply.github.com>
Date: Wed, 4 Mar 2026 19:01:02 +0300
Subject: [PATCH] hevc: assert and speed (#15122)

* hevc: assert and speed

* simpler
---
 .github/workflows/benchmark.yml |  2 +-
 extra/hevc/decode.py            | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index 399eeae8b9..83a5262320 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -332,7 +332,7 @@ jobs:
     # - name: Fuzz Padded Tensor Core GEMM (PTX)
     #   run: NV=1 NV_PTX=1 M_START=12 M_STOP=20 M_STEP=1 N_START=6 N_STOP=10 N_STEP=1 K_START=28 K_STOP=36 K_STEP=1 HALF=1 TC_OPT=2 python3 ./extra/gemm/fuzz_matmul.py
     - name: HEVC Decode Benchmark
-      run: VALIDATE=1 MAX_FRAMES=100 JITBEAM=1 NV=1 PYTHONPATH=. python3 extra/hevc/decode.py
+      run: VALIDATE=1 MAX_FRAMES=100 ASSERT_FPS=1400 JITBEAM=1 NV=1 PYTHONPATH=. python3 extra/hevc/decode.py
     - name: Train MNIST
       run: time PYTHONPATH=. NV=1 TARGET_EVAL_ACC_PCT=96.0 python3 examples/beautiful_mnist.py
     - name: Run 10 CIFAR training steps
diff --git a/extra/hevc/decode.py b/extra/hevc/decode.py
index b635590b0e..70c6df9ee9 100644
--- a/extra/hevc/decode.py
+++ b/extra/hevc/decode.py
@@ -10,9 +10,9 @@ HEVC_ROUNDUP = getenv("DATA_ROUNDUP", 32)
 @functools.cache
 def _hevc_jitted_decoder(out_image_size:tuple[int, int], max_hist:int, inplace:bool):
   def hevc_decode_frame(pos:Variable, hevc_tensor:Tensor, offset:Variable, sz:Variable, opaque:Tensor, i:Variable, *hist:Tensor, outbuf:Tensor|None=None):
-    x = hevc_tensor[offset:offset+sz*HEVC_ROUNDUP].decode_hevc_frame(pos, out_image_size, opaque[i], hist)
+    x = hevc_tensor[offset:offset+sz*HEVC_ROUNDUP].decode_hevc_frame(pos, out_image_size, opaque[i], hist).realize()
     if outbuf is not None: outbuf.assign(x).realize()
-    return x.realize()
+    return x
   return TinyJit(hevc_decode_frame)
 
 def hevc_decode(hevc_tensor:Tensor, opaque:Tensor, frame_info:list, luma_h:int, luma_w:int,
@@ -74,10 +74,14 @@ if __name__ == "__main__":
   Device.default.synchronize()
 
   # decode all frames using the iterator
-  with Timing("decoding whole file: ", on_exit=(lambda et: f", {len(frame_info)} frames, {len(frame_info)/(et/1e9):.2f} fps")):
+  tm = Timing("decoding whole file: ", on_exit=(lambda et: f", {len(frame_info)} frames, {len(frame_info)/(et/1e9):.2f} fps"))
+  with tm:
     images = list(hevc_decode(hevc_tensor, opaque_nv, frame_info, luma_h, luma_w, history=hist, preallocated_outputs=out_images))
     Device.default.synchronize()
 
+  fps = len(frame_info)/(tm.et/1e9)
+  assert fps >= getenv("ASSERT_FPS", 0), f"HEVC decode too slow: {fps:.2f} fps"
+
   # validation
   if getenv("VALIDATE", 0):
     import pickle