7.2.2 C*$* assert [no]bounds violations

The C*$* assert bounds violations assertion indicates that array subscript bounds may be violated during execution. If the user has not violated array subscript bounds, this assertion should not be used. A bounds violations assertion is active until reset or until the end of the program. For formal parameters, KAP treats a declared last dimension of (1) the same as (*).

The /assume=b command qualifier acts like a global C*$* assert bounds violations assertion.

In the following example, the first loop nest is assumed to be standard-conforming, so the loops can both be optimized. The loops can be interchanged to improve memory referencing, since no A(I,J) will overwrite an A(I',J+1) . In the second nest, the assertion warns KAP that the loop limit of the first array index (I) may violate the declared array bounds. KAP is cautious and optimizes only the right array index.

This code:

  DO 100 I = 1,M
     DO 100 J = 1,N
       A(I,J) = A(I,J) + B (I,J)
   100 CONTINUE
      C
       C*$*ASSERT BOUNDS VIOLATIONS
          DO 200 I = 1,M
           DO 200 J = 1,N
            A(I,J) = A(I,J) + B (I,J)
      200 CONTINUE

Becomes:

         DO 2 J=1,N
         DO 2 I=1,M
           A(I,J) = A(I,J) + B (I,J)
         2     CONTINUE
         C
         C*$* ASSERTBOUNDSVIOLATIONS
              DO 4 I=1,M
              DO 3 J=1,N
                 A(I,J) = A(I,J) + B (I,J)
          3    CONTINUE
          4    CONTINUE

Note

KAP always assumes that array references will be within the array itself, so the rightmost index will be safe to modify references to.

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