---
id: pr-flashinfer-3051
repo: flashinfer-ai/flashinfer
pr: 3051
title: 'feat: Add backend="b12x" for mm_fp4 on SM120'
author: bkryu
date: '2026-04-14'
url: https://github.com/flashinfer-ai/flashinfer/pull/3051
source_category: upstream-code
architectures:
- sm100
tags:
- fp4
- gemm
techniques: []
hardware_features:
- fp4
kernel_types:
- gemm
languages:
- cute-dsl
captured_at: '2026-04-27'
status: merged
merge_sha: 8c93f924f148cce491982089913e6f3ffb7f8cc8
inclusion_reason: kernel file changes
changed_paths:
- benchmarks/routines/gemm.py
- flashinfer/cute_dsl/utils.py
- flashinfer/gemm/__init__.py
- flashinfer/gemm/gemm_base.py
- flashinfer/gemm/kernels/dense_blockscaled_gemm_sm120.py
- tests/gemm/test_mm_fp4.py
head_ref_oid: 315e23e854dca1dea5bd062f25c26069080bd2e2
artifact_dir: evidence/pull-bundles/flashinfer/gh-3051
---
# feat: Add backend="b12x" for mm_fp4 on SM120

- Repository: `flashinfer-ai/flashinfer`
- PR: [3051](https://github.com/flashinfer-ai/flashinfer/pull/3051)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `benchmarks/routines/gemm.py`
- `flashinfer/cute_dsl/utils.py`
- `flashinfer/gemm/__init__.py`
- `flashinfer/gemm/gemm_base.py`
- `flashinfer/gemm/kernels/dense_blockscaled_gemm_sm120.py`
- `tests/gemm/test_mm_fp4.py`

## Evidence Bundle

`evidence/pull-bundles/flashinfer/gh-3051`
