!>
!> SLARMM returns a factor s in (0, 1] such that the linear updates
!>
!>    (s * C) - A * (s * B)  and  (s * C) - (s * A) * B
!>
!> cannot overflow, where A, B, and C are matrices of conforming
!> dimensions.
!>
!> This is an auxiliary routine so there is no argument checking.
!> 

!>          ANORM is REAL
!>          The infinity norm of A. ANORM >= 0.
!>          The number of rows of the matrix A.  M >= 0.
!> 

BNORM

!>          BNORM is REAL
!>          The infinity norm of B. BNORM >= 0.
!> 

CNORM

!>          CNORM is REAL
!>          The infinity norm of C. CNORM >= 0.
!> 

References: C. C. Kjelgaard Mikkelsen and L. Karlsson, Blocked Algorithms for Robust Solution of Triangular Linear Systems. In: International Conference on Parallel Processing and Applied Mathematics, pages 68--78. Springer, 2017.