Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Use BLAS.trsm! instead of LAPACK.trtrs! in left-triangular solves #1194

Open
wants to merge 5 commits into
base: master
Choose a base branch
from
+25 −5
Open

Use BLAS.trsm! instead of LAPACK.trtrs! in left-triangular solves #1194

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
c51bad0
Use `BLAS.trsm!` instead of `LAPACK.trtrs!` in left-triangular solves
dkarrasch Feb 4, 2025
054c8c6
add singularity checks
dkarrasch Feb 4, 2025
c563b4b
add tests
dkarrasch Feb 4, 2025
711aceb
fix mistake
dkarrasch Feb 4, 2025
f8850f0
use SingularException
dkarrasch Feb 4, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
13 changes: 12 additions & 1 deletion src/blas.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -84,7 +84,8 @@ export
trsm!,
trsm

using ..LinearAlgebra: libblastrampoline, BlasReal, BlasComplex, BlasFloat, BlasInt, DimensionMismatch, checksquare, chkstride1
using ..LinearAlgebra: libblastrampoline, BlasReal, BlasComplex, BlasFloat, BlasInt,
DimensionMismatch, checksquare, chkstride1, SingularException

include("lbt.jl")

Expand Down Expand Up @@ -1369,6 +1370,11 @@ for (fname, elty) in ((:dtrsv_,:Float64),
throw(DimensionMismatch(lazy"size of A is $n != length(x) = $(length(x))"))
end
chkstride1(A)
if diag == 'N'
for i in 1:n
iszero(A[i,i]) && throw(SingularException(i))
end
end
px, stx = vec_pointer_stride(x, ArgumentError("input vector with 0 stride is not allowed"))
GC.@preserve x ccall((@blasfunc($fname), libblastrampoline), Cvoid,
(Ref{UInt8}, Ref{UInt8}, Ref{UInt8}, Ref{BlasInt},
Expand Down Expand Up @@ -2217,6 +2223,11 @@ for (mmname, smname, elty) in
end
chkstride1(A)
chkstride1(B)
if diag == 'N'
for i in 1:k
iszero(A[i,i]) && throw(SingularException(i))
end
end
ccall((@blasfunc($smname), libblastrampoline), Cvoid,
(Ref{UInt8}, Ref{UInt8}, Ref{UInt8}, Ref{UInt8},
Ref{BlasInt}, Ref{BlasInt}, Ref{$elty}, Ptr{$elty},
Expand Down
8 changes: 5 additions & 3 deletions src/triangular.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1223,11 +1223,13 @@ function generic_mattrimul!(C::StridedMatrix{T}, uploc, isunitc, tfun::Function,
end
end
# division
function generic_trimatdiv!(C::StridedVecOrMat{T}, uploc, isunitc, tfun::Function, A::StridedMatrix{T}, B::AbstractVecOrMat{T}) where {T<:BlasFloat}
generic_trimatdiv!(C::StridedVector{T}, uploc, isunitc, tfun::Function, A::StridedMatrix{T}, B::AbstractVector{T}) where {T<:BlasFloat} =
BLAS.trsv!(uploc, tfun === identity ? 'N' : tfun === transpose ? 'T' : 'C', isunitc, A, C === B ? C : copyto!(C, B))
function generic_trimatdiv!(C::StridedVecOrMat{T}, uploc, isunitc, tfun::Function, A::StridedMatrix{T}, B::AbstractMatrix{T}) where {T<:BlasFloat}
if stride(C,1) == stride(A,1) == 1
LAPACK.trtrs!(uploc, tfun === identity ? 'N' : tfun === transpose ? 'T' : 'C', isunitc, A, C === B ? C : copyto!(C, B))
BLAS.trsm!('L', uploc, tfun === identity ? 'N' : tfun === transpose ? 'T' : 'C', isunitc, one(T), A, C === B ? C : copyto!(C, B))
else # incompatible with LAPACK
@invoke generic_trimatdiv!(C::AbstractVecOrMat, uploc, isunitc, tfun::Function, A::AbstractMatrix, B::AbstractVecOrMat)
@invoke generic_trimatdiv!(C::AbstractVecOrMat, uploc, isunitc, tfun::Function, A::AbstractMatrix, B::AbstractMatrix)
end
end
function generic_mattridiv!(C::StridedMatrix{T}, uploc, isunitc, tfun::Function, A::AbstractMatrix{T}, B::StridedMatrix{T}) where {T<:BlasFloat}
Expand Down
2 changes: 2 additions & 0 deletions test/testtriag.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -493,6 +493,8 @@ function test_triangular(elty1_types)
@test_throws DimensionMismatch transpose(Ann) \ bm
if t1 == UpperTriangular || t1 == LowerTriangular
@test_throws SingularException ldiv!(t1(zeros(elty1, n, n)), fill(eltyB(1), n))
@test_throws SingularException ldiv!(t1(zeros(elty1, n, n)), fill(eltyB(1), n, 2))
@test_throws SingularException rdiv!(fill(eltyB(1), n, n), t1(zeros(elty1, n, n)))
end
@test B / A1 ≈ B / M1
@test B / transpose(A1) ≈ B / transpose(M1)
Expand Down
7 changes: 6 additions & 1 deletion test/triangular.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -886,8 +886,13 @@ end
end
end

@testset "(l/r)mul! and (l/r)div! for non-contiguous matrices" begin
@testset "(l/r)mul! and (l/r)div! for non-contiguous arrays" begin
U = UpperTriangular(reshape(collect(3:27.0),5,5))
b = float.(1:10)
b2 = copy(b); b2v = view(b2, 1:2:9); b2vc = copy(b2v)
@test lmul!(U, b2v) == lmul!(U, b2vc)
b2 = copy(b); b2v = view(b2, 1:2:9); b2vc = copy(b2v)
@test ldiv!(U, b2v) ≈ ldiv!(U, b2vc)
B = float.(collect(reshape(1:100, 10,10)))
B2 = copy(B); B2v = view(B2, 1:2:9, 1:5); B2vc = copy(B2v)
@test lmul!(U, B2v) == lmul!(U, B2vc)
Expand Down