The /case qualifier tells KAP to distinguish between
uppercase and lowercase in identifier names. The default
/nocase tells KAP to be case insensitive in variable names.
When KAP inserts or modifies lines in a program, it usually creates
the new code in all capital letters. The /case
qualifier requires KAP to preserve the original case of variables
in the new code.
In the following example, the /nocase default would
cause KAP to interpret N and n as the
same variable. This presents an unoptimizable data dependence in the
loop.
n = N + 1
DO 10 I = 2,100
A(I,N) = A(I-1,n)
10 CONTINUE
When the /case qualifier is specified, N
and n are treated as different variables. The Global
Forward Substitution pass of KAP recognizes the assignment of
different values to N and n and resolves
the data dependence.
DO 2 I=2,100
A(I,N) = A(I-1,N+1)
2 CONTINUE