Add quick return if scaling with one (Reference-LAPACK PR674)

Author: martin-frbg

lapack-netlib/SRC/clascl.f

@@ -272,6 +272,8 @@ SUBROUTINE CLASCL( TYPE, KL, KU, CFROM, CTO, M, N, A, LDA, INFO )
          ELSE
             MUL = CTOC / CFROMC
             DONE = .TRUE.
+            IF (MUL .EQ. ONE)
+     $         RETURN
          END IF
       END IF
 *

lapack-netlib/SRC/dlascl.f

@@ -272,6 +272,8 @@ SUBROUTINE DLASCL( TYPE, KL, KU, CFROM, CTO, M, N, A, LDA, INFO )
          ELSE
             MUL = CTOC / CFROMC
             DONE = .TRUE.
+            IF (MUL .EQ. ONE)
+     $         RETURN
          END IF
       END IF
 *

lapack-netlib/SRC/slascl.f

@@ -272,6 +272,8 @@ SUBROUTINE SLASCL( TYPE, KL, KU, CFROM, CTO, M, N, A, LDA, INFO )
          ELSE
             MUL = CTOC / CFROMC
             DONE = .TRUE.
+            IF (MUL .EQ. ONE)
+     $         RETURN
          END IF
       END IF
 *

lapack-netlib/SRC/zlascl.f

@@ -272,6 +272,8 @@ SUBROUTINE ZLASCL( TYPE, KL, KU, CFROM, CTO, M, N, A, LDA, INFO )
          ELSE
             MUL = CTOC / CFROMC
             DONE = .TRUE.
+            IF (MUL .EQ. ONE)
+     $         RETURN
          END IF
       END IF
 *