[inductor][heuristics] Update total tiling score when it is zero (#176423)

kundaMwiza · pytorchmergebot · commit 09516026cf84 · 2026-03-09T10:52:03.000Z
- When the total score is zero, it should be updated otherwise there will be a division by zero error - Trying to create a repro proved difficult. Example state that produces this is: ```python size_hints = {"y": 4096, "x": 64, "r0_": 128} inductor_meta = { "tiling_scores": {"y": 134217728, "x": 2097152, "r0_": 0}, "num_load": 1, } triton_meta = { "signature": { "in_ptr0": "*fp32", "out_ptr0": "*fp32", "ynumel": "i32", "xnumel": "i32", "r0_numel": "i32", "YBLOCK": "constexpr", "XBLOCK": "constexpr", "R0_BLOCK": "constexpr", } } persistent_reduction=False ``` Pull Request resolved: #176423 Approved by: https://github.com/jansel
diff --git a/torch/_inductor/runtime/triton_heuristics.py b/torch/_inductor/runtime/triton_heuristics.py
@@ -3389,6 +3389,7 @@ def match_target_block_product(
         # just assume even score with no minimum block size
         min_block_size = 1
         tiling_scores = dict.fromkeys(tiling_scores.keys(), target_block_product)
+        total_score = target_block_product * len(tiling_scores)
 
     # First, give each coalescing dimension at least min_block_size
     block_sizes = {}
