SparseMatMul
int64 ii1(?)
int64 jj1(?)
double vv1(?)
int64 ii2(?)
int64 jj2(?)
double vv2(?)
int64 m()
int64 n()
int64 k()
int64 ii3(?) -> output
int64 jj3(?) -> output
double vv3(?) -> output