• There are 36 files with units, with 11,055 lines of code.
• 0 very complex files (McCabe index sum 251+; 0 lines of code)
• 1 complex files (McCabe index sum 126-250; 1,440 lines of code)
• 3 medium complex files (McCabe index sum 51-125; 3,321 lines of code)
• 5 slightly complex files (McCabe index sum 26-50; 2,293 lines of code)
• 27 simple files (McCabe index sum 1-25; 4,001 lines of code)
• 61 main files have no units (e.g. languages without unit analysis, or files without functions) and are not classified.

The McCabe index of a file grows with its size: per 100 lines tells a large but plain file from a dense one, and most complex unit whether the complexity sits in one unit or is spread over many.

File	# lines	# units	McCabe index (sum)	per 100 lines	most complex unit
kernel_body.h in csrc/ascend_kernels/prefill/sparse	1440	16	196	14	108
sm100_fmha_bwd_kernel_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	1416	16	108	8	35
sm100_fmha_bwd_mla_kernel_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	1414	16	107	8	35
sm100_fmha_fwd_kernel_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	491	11	82	17	60
fmha_fusion.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	277	21	47	17	8
sm100_fmha_mla_fwd_mainloop_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	814	20	41	5	3
sm100_fmha_fwd_mainloop_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	805	20	40	5	3
common.h in csrc/api	223	14	35	16	8
pipeline_mla.hpp in csrc/cuda_kernels/sm100/prefill/dense/common	174	12	28	16	7
fused_norm_rope_attn_rope_cast_fwd.cpp in csrc/api	462	6	24	5	16
common_subroutine.h in csrc/cuda_kernels/sm100	168	5	23	14	10
fmha_kernel_bwd_convert.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	100	8	18	18	6
sparse_decode.cpp in csrc/api	396	9	17	4	6
fmha_kernel_bwd_sum_OdO.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	106	7	17	16	10
sparse_prefill.cpp in csrc/api	195	6	15	8	10
sm100_fmha_mla_load_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	220	5	13	6	4
sm100_fmha_fwd_epilogue_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	148	6	12	8	3
flash_mla_interface.py in flash_mla	321	11	12	4	2
fmha_common.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	84	5	11	13	5
sm100_fmha_load_tma_warpspecialized.hpp in csrc/cuda_kernels/sm100/prefill/dense/collective	205	4	11	5	4
config.h in csrc/cuda_kernels/sm100/prefill/sparse/fused_norm_rope_attn_rope_cast_fwd/core_attn	198	4	11	6	5
fmha_causal_tile_scheduler.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	117	8	10	9	2
fmha_tile_scheduler.hpp in csrc/cuda_kernels/sm100/prefill/dense/kernel	96	8	9	9	2
helpers.h in csrc/cuda_kernels/sm100	196	9	9	5	1
generate_instantiations.py in scripts	45	2	9	20	7
fmha.hpp in csrc/cuda_kernels/sm100/prefill/dense/device	168	3	8	5	4
gather_tensor.hpp in csrc/cuda_kernels/sm100/prefill/dense/common	142	3	7	5	4
kv_cache_format.h in csrc/cuda_kernels	45	2	6	13	3
utils.h in csrc/cuda_kernels	37	4	4	11	1
pow_2.hpp in csrc/cuda_kernels/sm100/prefill/dense/common	45	3	4	9	2
fast_div_mod.h in csrc/ascend_kernels/prefill/sparse	28	2	4	14	3
fused_norm_rope_attn_rope_cast.py in flash_mla	77	4	4	5	1
fmha_device_bwd.hpp in csrc/cuda_kernels/sm100/prefill/dense/device	237	3	3	1	1
config.h in csrc/ascend_kernels/prefill/sparse	139	1	2	1	2
dense_fwd.cpp in csrc/api	13	1	1	8	1
dense_bwd.cpp in csrc/api	13	1	1	8	1

• File complexity is the sum of the McCabe indexes (conditional complexity) of the units (methods, functions...) in a file.
• Files are classified in five categories based on that sum: 1-25 (simple files), 26-50 (slightly complex files), 51-125 (medium complex files), 126-250 (complex files), 251+ (very complex files). The default bands are five times the unit complexity bands, as a file is a group of units.
• Only main code files with units are classified. Files without units (languages without unit analysis, or files without functions) have no complexity to measure and are left out rather than counted as simple.
• A very complex file holds many decisions, which often means it has too many responsibilities: a candidate to split, and a place where changes need more testing.