LAPACK: Aggressive constprop to concretely infer syev!/syevd! (#55295)

Currently, these are inferred as a 2-Tuple of possible return types depending on `jobz`, but since `jobz` is usually a constant, we may propagate it aggressively and have the return types inferred concretely.
JuliaLang · Jul 30, 2024 · 686804d · 686804d
1 parent 125bac4
commit 686804d
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Showing 2 changed files with 14 additions and 4 deletions.
diff --git a/stdlib/LinearAlgebra/src/lapack.jl b/stdlib/LinearAlgebra/src/lapack.jl
@@ -5329,7 +5329,7 @@ for (syev, syevr, syevd, sygvd, elty) in
         #       INTEGER            INFO, LDA, LWORK, N
         # *     .. Array Arguments ..
         #       DOUBLE PRECISION   A( LDA, * ), W( * ), WORK( * )
-        function syev!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
+        Base.@constprop :aggressive function syev!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
             require_one_based_indexing(A)
             @chkvalidparam 1 jobz ('N', 'V')
             chkuplo(uplo)
@@ -5429,7 +5429,7 @@ for (syev, syevr, syevd, sygvd, elty) in
         # *     .. Array Arguments ..
         #       INTEGER            IWORK( * )
         #       DOUBLE PRECISION   A( LDA, * ), W( * ), WORK( * )
-        function syevd!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
+        Base.@constprop :aggressive function syevd!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
             require_one_based_indexing(A)
             @chkvalidparam 1 jobz ('N', 'V')
             chkstride1(A)
@@ -5526,7 +5526,7 @@ for (syev, syevr, syevd, sygvd, elty, relty) in
         # *     .. Array Arguments ..
         #       DOUBLE PRECISION   RWORK( * ), W( * )
         #       COMPLEX*16         A( LDA, * ), WORK( * )
-        function syev!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
+        Base.@constprop :aggressive function syev!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
             require_one_based_indexing(A)
             @chkvalidparam 1 jobz ('N', 'V')
             chkstride1(A)
@@ -5639,7 +5639,7 @@ for (syev, syevr, syevd, sygvd, elty, relty) in
         #       INTEGER            IWORK( * )
         #       DOUBLE PRECISION   RWORK( * )
         #       COMPLEX*16         A( LDA, * ), WORK( * )
-        function syevd!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
+        Base.@constprop :aggressive function syevd!(jobz::AbstractChar, uplo::AbstractChar, A::AbstractMatrix{$elty})
             require_one_based_indexing(A)
             @chkvalidparam 1 jobz ('N', 'V')
             chkstride1(A)

diff --git a/stdlib/LinearAlgebra/test/lapack.jl b/stdlib/LinearAlgebra/test/lapack.jl
@@ -889,4 +889,14 @@ end
     @test UpperTriangular(A) == UpperTriangular(B)
 end
 
+@testset "inference in syev!/syevd!" begin
+    for T in (Float32, Float64), CT in (T, Complex{T})
+        A = rand(CT, 4,4)
+        @inferred (A -> LAPACK.syev!('N', 'U', A))(A)
+        @inferred (A -> LAPACK.syev!('V', 'U', A))(A)
+        @inferred (A -> LAPACK.syevd!('N', 'U', A))(A)
+        @inferred (A -> LAPACK.syevd!('V', 'U', A))(A)
+    end
+end
+
 end # module TestLAPACK