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[flang] edits 

Original-commit: flang-compiler/f18@07da944e4b
Reviewed-on: https://github.com/flang-compiler/f18/pull/534
Tree-same-pre-rewrite: false
This commit is contained in:
peter klausler 2019-06-28 13:53:05 -07:00
parent f0778f0fe2
commit e73a1d287a
1 changed files with 4 additions and 3 deletions
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7
flang/documentation/ArrayComposition.md
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@ -47,7 +47,7 @@ intrinsic operators and elemental functions.
Fortran doesn't allow one to apply subscripts directly to an expression, Fortran doesn't allow one to apply subscripts directly to an expression,
but expressions have rank and shape, and one can view array expressions but expressions have rank and shape, and one can view array expressions
as functions over index tuples by applying those indices to the arrays as functions over index tuples by applying those indices to the arrays
in the expression. and subexpressions in the expression.
Consider `B = A + 1.0` (assuming `REAL :: A(N,M), B(N,M)`). Consider `B = A + 1.0` (assuming `REAL :: A(N,M), B(N,M)`).
The right-hand side of that assignment could be evaluated into a The right-hand side of that assignment could be evaluated into a
@ -61,7 +61,7 @@ END DO
DO CONCURRENT(J=1:N,K=1:M) DO CONCURRENT(J=1:N,K=1:M)
B(J,K)=T(J,K) B(J,K)=T(J,K)
END DO END DO
DEALLOCATE(T(N,M)) DEALLOCATE(T)
``` ```
But we can avoid the allocation, population, and deallocation of But we can avoid the allocation, population, and deallocation of
the temporary by treating the right-hand side expression as if it the temporary by treating the right-hand side expression as if it
@ -83,7 +83,8 @@ Transformational intrinsic functions as function composition
Many of the transformational intrinsic functions listed above Many of the transformational intrinsic functions listed above
can, when their array arguments are viewed as functions over their can, when their array arguments are viewed as functions over their
index tuples, be seen as compositions of those functions with index tuples, be seen as compositions of those functions with
functions of the "incoming" indices. functions of the "incoming" indices -- yielding a function for
an entire right-hand side of an array assignment statement.
For example, the application of `TRANSPOSE(A + 1.0)` to the index For example, the application of `TRANSPOSE(A + 1.0)` to the index
tuple `(J,K)` becomes `A(K,J) + 1.0`. tuple `(J,K)` becomes `A(K,J) + 1.0`.