JuliaLang / julia / #37864

86%

Build Type

push

local

Committed by web-flow

Commit Message

Improve performance in `Bidiagonal` times `Diagonal` (#55175)

This adds specialized methods to improve performance, and avoid
allocations that were arising currently from the fallback tridiagonal
implementations.

```julia
julia> using LinearAlgebra, BenchmarkTools

julia> n = 10000; B = Bidiagonal(rand(n), rand(n-1), :U); D = Diagonal(rand(size(B,1))); C = similar(B, size(B));

julia> @btime mul!($C, $B, $D);
  25.552 ms (3 allocations: 78.19 KiB) # v"1.12.0-DEV.870"
  25.559 ms (0 allocations: 0 bytes) # This PR

julia> C = similar(B);

julia> @btime mul!($C, $B, $D);
  23.551 μs (3 allocations: 78.19 KiB)  # v"1.12.0-DEV.870"
  7.123 μs (0 allocations: 0 bytes) # This PR, specialized method
```

Run Details

112 of 117 new or added lines in 1 file covered. (95.73%)

10 existing lines in 6 files now uncovered.

77896 of 88909 relevant lines covered (87.61%)

16086101.09 hits per line