Add dgeev_ implementation

Author: pedrovgs

Sources/Matft/library/lapack.swift

@@ -758,8 +758,26 @@ private func clapack_dgetri_(
     _ info: UnsafeMutablePointer<CLong>
 ) -> Void
 
+@_silgen_name("dgeev_")
+private func clapack_dgeev_(
+    _ jobvl: UnsafeMutablePointer<CChar>,
+    _ jobvr: UnsafeMutablePointer<CChar>,
+    _ n: UnsafeMutablePointer<CLong>,
+    _ a: UnsafeMutablePointer<Double>,
+    _ lda: UnsafeMutablePointer<CLong>,
+    _ wr: UnsafeMutablePointer<Double>,
+    _ wi: UnsafeMutablePointer<Double>,
+    _ vl: UnsafeMutablePointer<Double>,
+    _ ldvl: UnsafeMutablePointer<CLong>,
+    _ vr: UnsafeMutablePointer<Double>,
+    _ ldvr: UnsafeMutablePointer<CLong>,
+    _ work: UnsafeMutablePointer<Double>,
+    _ lwork: UnsafeMutablePointer<CLong>,
+    _ info: UnsafeMutablePointer<CLong>
+) -> Void
+
 // MARK: - CLAPACK Wrapper Functions for WASI
-// Only dgetrf_ and dgetri_ are available in the CLAPACK eigen-support branch
+// dgetrf_, dgetri_, and dgeev_ are available in the CLAPACK eigen-support branch
 
 @inline(__always)
 internal func sgesv_(_ n: UnsafeMutablePointer<__CLPK_integer>, _ nrhs: UnsafeMutablePointer<__CLPK_integer>, _ a: UnsafeMutablePointer<Float>, _ lda: UnsafeMutablePointer<__CLPK_integer>, _ ipiv: UnsafeMutablePointer<__CLPK_integer>, _ b: UnsafeMutablePointer<Float>, _ ldb: UnsafeMutablePointer<__CLPK_integer>, _ info: UnsafeMutablePointer<__CLPK_integer>) -> Int32 {
@@ -825,7 +843,19 @@ internal func sgeev_(_ jobvl: UnsafeMutablePointer<Int8>, _ jobvr: UnsafeMutable
 
 @inline(__always)
 internal func dgeev_(_ jobvl: UnsafeMutablePointer<Int8>, _ jobvr: UnsafeMutablePointer<Int8>, _ n: UnsafeMutablePointer<__CLPK_integer>, _ a: UnsafeMutablePointer<Double>, _ lda: UnsafeMutablePointer<__CLPK_integer>, _ wr: UnsafeMutablePointer<Double>, _ wi: UnsafeMutablePointer<Double>, _ vl: UnsafeMutablePointer<Double>, _ ldvl: UnsafeMutablePointer<__CLPK_integer>, _ vr: UnsafeMutablePointer<Double>, _ ldvr: UnsafeMutablePointer<__CLPK_integer>, _ work: UnsafeMutablePointer<Double>, _ lwork: UnsafeMutablePointer<__CLPK_integer>, _ info: UnsafeMutablePointer<__CLPK_integer>) -> Int32 {
-    fatalError("LAPACK dgeev_ is not available on WASI (double-precision eigenvalue decomposition not supported)")
+    // Convert Int32 parameters to CLong for CLAPACK
+    var nLong = CLong(n.pointee)
+    var ldaLong = CLong(lda.pointee)
+    var ldvlLong = CLong(ldvl.pointee)
+    var ldvrLong = CLong(ldvr.pointee)
+    var lworkLong = CLong(lwork.pointee)
+    var infoLong: CLong = 0
+
+    // Use correctly-typed function to avoid ABI mismatch (CLAPACK returns void, not int)
+    clapack_dgeev_(jobvl, jobvr, &nLong, a, &ldaLong, wr, wi, vl, &ldvlLong, vr, &ldvrLong, work, &lworkLong, &infoLong)
+
+    info.pointee = __CLPK_integer(infoLong)
+    return Int32(infoLong)
 }
 
 @inline(__always)