[all-commits] [llvm/llvm-project] 2e81ba: [NVVM][MLIR] Fixed valgrind leak in MMAOp (#208063)

[Stefan Mada via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2e81babdf17d29d2b7e833137f92a598f76a8cbb
      https://github.com/llvm/llvm-project/commit/2e81babdf17d29d2b7e833137f92a598f76a8cbb
  Author: Stefan Mada <smada at nvidia.com>
  Date:   2026-07-09 (Thu, 09 Jul 2026)

  Changed paths:
    M mlir/include/mlir/Dialect/LLVMIR/NVVMOps.td

  Log Message:
  -----------
  [NVVM][MLIR] Fixed valgrind leak in MMAOp (#208063)

MmaOp::getIntrinsicID triggers an uninitialized-read warning under
Valgrind. `intOverflowBehavior` is optional; in the generated selector
its `has_value()` guarded access can be speculatively loaded before the
guard, reading the empty std::optional's uninitialized payload.

The read is benign: the payload is correctly stack-allocated but
uninitialized while empty, and the loaded value is discarded by the
guard, so this is not incorrect / undefined behavior.

This MR keeps the attribute as optional, but the lowering now resolves
it to a concrete value (wrapped when omitted) before calling
getIntrinsicID, so the selector always reads an initialized value.
`wrapped` matches the PTX spec and the existing lowering, where an
omitted attribute already selected the non-satfinite intrinsic;
intrinsic selection and printed IR are unchanged. Documentation updated
to correct the stale default.



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