Make Eigen blas usage more robust trough -Xclang Definition

CMakeLists.txt

@@ -9,16 +9,31 @@ message("Found LLVM at: " ${Enzyme_LLVM_BINARY_DIR})
 set(CMAKE_C_COMPILER "${Enzyme_LLVM_BINARY_DIR}/bin/clang")
 set(CMAKE_CXX_COMPILER "${Enzyme_LLVM_BINARY_DIR}/bin/clang++")
 
-project(EnzymeExample)
+set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --save-temps -Xclang -D -Xclang EIGEN_USE_BLAS -Xclang -no-opaque-pointers")
+set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --save-temps -Xclang -D -Xclang EIGEN_USE_BLAS -Xclang -no-opaque-pointers")
+
+project(EnzymeExample CXX)
+
+set(BLA_VENDER OpenBLAS)
+find_package(BLAS REQUIRED)
+if(BLAS_FOUND)
+    message("OpenBLAS found.")
+    #include_directories(/opt/OpenBLAS/include/)
+    #target_link_libraries(main.exe ${BLAS_LIBRARIES})
+endif(BLAS_FOUND)
 
 message("found dir ${Enzyme_DIR}")
 message("found ${Enzyme_FOUND}")
 get_property(importTargetsAfter DIRECTORY "${CMAKE_SOURCE_DIR}" PROPERTY IMPORTED_TARGETS)
 message("imported targets ${importTargetsAfter}")
 
+
+find_package (Eigen3 3.3 REQUIRED NO_MODULE)
+
+
 add_executable(example
-    multisource.c
+    multisource.cpp
     myblas.c
     myblas.h
 )
-target_link_libraries(example PUBLIC LLDEnzymeFlags)
+target_link_libraries(example PUBLIC LLDEnzymeFlags Eigen3::Eigen ${BLAS_LIBRARIES})

multisource.cpp

@@ -0,0 +1,70 @@
+#include "myblas.h"
+#include <assert.h>
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+// #define EIGEN_USE_BLAS
+
+#include<Eigen/Core>
+
+double dotabs(struct complex* alpha, struct complex* beta, int n) {
+  struct complex prod = myblas_cdot(alpha, beta, n);
+  return myblas_cabs(prod);
+}
+
+void __enzyme_autodiff(void*, ...);
+int enzyme_const, enzyme_dup, enzyme_out;
+
+using Eigen::MatrixXd;
+using Eigen::VectorXd;
+
+void foo(MatrixXd *m, VectorXd *v) { *v = *m * *v; }
+
+int main(int argc, char *argv[]) {
+  // int size = 50;
+  //// VectorXf is a vector of floats, with dynamic size.
+  // Eigen::VectorXf u(size), v(size), w(size);
+  // u = v + w;
+
+  MatrixXd m = MatrixXd::Random(30, 30);
+  MatrixXd dm = MatrixXd::Random(30, 30);
+  m = (m + MatrixXd::Constant(30, 30, 1.2)) * 50;
+  std::cout << "m =" << std::endl << m << std::endl;
+  VectorXd v = VectorXd::Random(30);
+  VectorXd dv = VectorXd::Random(30);
+  // v << 1, 2, 3;
+  // std::cout << "m * v =" << std::endl << m * v << std::endl;
+
+  __enzyme_autodiff((void *)foo, &m, &dm, &v, &dv);
+  std::cout << "dm, dv: =" << std::endl << dm << std::endl << dv << std::endl;
+
+  // int n = 3;
+  // if (argc > 1) {
+  //   n = atoi(argv[1]);
+  // }
+
+  // struct complex *A = (struct complex*)malloc(sizeof(struct complex) * n);
+  // assert(A != 0);
+  // for(int i=0; i<n; i++)
+  //  A[i] = (struct complex){(i+1), (i+2)};
+
+  // struct complex *grad_A = (struct complex*)malloc(sizeof(struct complex) *
+  // n); assert(grad_A != 0); for(int i=0; i<n; i++)
+  //  grad_A[i] = (struct complex){0,0};
+
+  // struct complex *B = (struct complex*)malloc(sizeof(struct complex) * n);
+  // assert(B != 0);
+  // for(int i=0; i<n; i++)
+  //  B[i] = (struct complex){-3-i, 2*i};
+
+  // struct complex *grad_B = (struct complex*)malloc(sizeof(struct complex) *
+  // n); assert(grad_B != 0); for(int i=0; i<n; i++)
+  //  grad_B[i] = (struct complex){0,0};
+
+  //__enzyme_autodiff((void*)dotabs, A, grad_A, B, grad_B, n);
+  // printf("Gradient dotabs(A)[0] = %f\n", grad_A[0].r);
+
+  return 0;
+}