Take advantage of sparsity in blasmul! (#18)

* Take advantage of sparsity in blasmul!

* Update runtests.jl

Author: dlfivefifty

.gitignore

@@ -3,3 +3,4 @@
 *.jl.mem
 deps/deps.jl
 Manifest.toml
+.DS_Store

Project.toml

@@ -1,7 +1,7 @@
 name = "ArrayLayouts"
 uuid = "4c555306-a7a7-4459-81d9-ec55ddd5c99a"
 authors = ["Sheehan Olver <[email protected]>"]
-version = "0.3.0"
+version = "0.3.1"
 
 [deps]
 FillArrays = "1a297f60-69ca-5386-bcde-b61e274b549b"

src/muladd.jl

@@ -181,7 +181,7 @@ function default_blasmul!(α, A::AbstractMatrix, B::AbstractMatrix, β, C::Abstr
     (iszero(mA) || iszero(nB)) && return C
     iszero(nA) && return lmul!(β, C)
 
-    @inbounds for k in colsupport(A), j in rowsupport(B)
+    @inbounds for k in colsupport(A), j in rowsupport(B,rowsupport(A,k))
         z2 = zero(A[k, 1]*B[1, j] + A[k, 1]*B[1, j])
         Ctmp = convert(promote_type(eltype(C), typeof(z2)), z2)
         @simd for ν = rowsupport(A,k) ∩ colsupport(B,j)

test/runtests.jl

@@ -1,4 +1,4 @@
-using ArrayLayouts, Random, Test
+using ArrayLayouts, Random, FillArrays, Test
 import ArrayLayouts: MemoryLayout, @_layoutlmul, triangulardata
 
 Random.seed!(0)
@@ -47,6 +47,22 @@ MemoryLayout(::Type{MyMatrix}) = DenseColumnMajor()
 
     @test qr(A) isa LinearAlgebra.QRCompactWY
     @test inv(A) ≈ inv(A.A)
+
+    Bin = randn(5,5)
+    B = MyMatrix(copy(Bin))
+    muladd!(1.0, A, A, 2.0, B)
+    @test all(B .=== A.A^2 + 2Bin)
+
+    # tiled_blasmul!
+    B = MyMatrix(copy(Bin))
+    muladd!(1.0, Ones(5,5), A, 2.0, B)
+
+    #generic_blasmul!
+    A = BigFloat.(randn(5,5))
+    Bin = BigFloat.(randn(5,5))
+    B = copy(Bin)
+    muladd!(1.0, Ones(5,5), A, 2.0, B)
+    @test B == Ones(5,5)*A + 2.0Bin
 end
 
 struct MyUpperTriangular{T} <: AbstractMatrix{T}