Commit f274e125 authored by Raymond Toy's avatar Raymond Toy
Browse files

Fix some bad markup

parent 64e5f754
...@@ -181,8 +181,7 @@ For a more detailed list of issues and notes, see src/NOTES. ...@@ -181,8 +181,7 @@ For a more detailed list of issues and notes, see src/NOTES.
We highlight just a few issues here. We highlight just a few issues here.
o Block data statements. * Block data statements.
In Fortran, block data statments are used to initialize common In Fortran, block data statments are used to initialize common
blocks. Since Fortran executables are loaded and run just once, blocks. Since Fortran executables are loaded and run just once,
this is not a problem. However, in Lisp, this might not be true, this is not a problem. However, in Lisp, this might not be true,
...@@ -190,8 +189,7 @@ o Block data statements. ...@@ -190,8 +189,7 @@ o Block data statements.
up to you to run the block data initializer at the right time, as up to you to run the block data initializer at the right time, as
needed. f2cl cannot know when and where to call the initializer. needed. f2cl cannot know when and where to call the initializer.
o Common blocks. * Common blocks.
F2cl converts common blocks to structures. However, common blocks F2cl converts common blocks to structures. However, common blocks
may be referenced in several different files, so the user must may be referenced in several different files, so the user must
tell f2cl when to define the structure. Use the :declare-common tell f2cl when to define the structure. Use the :declare-common
...@@ -204,13 +202,13 @@ o Common blocks. ...@@ -204,13 +202,13 @@ o Common blocks.
changes how f2cl handles common blocks. A rather common use of changes how f2cl handles common blocks. A rather common use of
common blocks has the same common block using different variable common blocks has the same common block using different variable
names. For example, one routine might have names. For example, one routine might have
```
COMMON /foo/ a(10), b, i(4) COMMON /foo/ a(10), b, i(4)
```
and another might say and another might say
```
COMMON /foo/ b(9), c, d, j(2), k(2) COMMON /foo/ b(9), c, d, j(2), k(2)
```
In Fortran, this is perfectly acceptable. Normally, f2cl expects In Fortran, this is perfectly acceptable. Normally, f2cl expects
all common blocks to use the same variable names, and then f2cl all common blocks to use the same variable names, and then f2cl
creates a structure for the common block using the variable names creates a structure for the common block using the variable names
...@@ -218,11 +216,11 @@ o Common blocks. ...@@ -218,11 +216,11 @@ o Common blocks.
f2cl gets confused. Hence, :common-as-array. We treat the common f2cl gets confused. Hence, :common-as-array. We treat the common
block as an array of memory. So this gets converted into a block as an array of memory. So this gets converted into a
structure somewhat like structure somewhat like
```
(defstruct foo (defstruct foo
(part-0 (make-array 11 :element-type 'real)) (part-0 (make-array 11 :element-type 'real))
(part-1 (make-array 4 :element-type 'integer4))) (part-1 (make-array 4 :element-type 'integer4)))
```
(In a more general case, we group all contiguous variables of the (In a more general case, we group all contiguous variables of the
same type into one array. f2cl and Lisp cannot handle the case same type into one array. f2cl and Lisp cannot handle the case
where a real and integer value are allocated to the same piece of where a real and integer value are allocated to the same piece of
...@@ -231,7 +229,7 @@ o Common blocks. ...@@ -231,7 +229,7 @@ o Common blocks.
Then in the individual routines, symbol-macrolets are used to Then in the individual routines, symbol-macrolets are used to
create accessors for the various definitions. Hence, for the create accessors for the various definitions. Hence, for the
second version, we would do something like second version, we would do something like
```
(symbol-macrolet (symbol-macrolet
(b (make-array 9 :displaced-to (b (make-array 9 :displaced-to
(foo-part-0 *foo*) (foo-part-0 *foo*)
...@@ -245,15 +243,14 @@ o Common blocks. ...@@ -245,15 +243,14 @@ o Common blocks.
(foo-part-1 *foo*) (foo-part-1 *foo*)
:displaced-offset 2)) :displaced-offset 2))
...) ...)
```
Thus, we access the right parts of the common block, independent Thus, we access the right parts of the common block, independent
of the name. Note that this has a performance impact since we of the name. Note that this has a performance impact since we
used displaced arrays. used displaced arrays.
o Conversion order. * Conversion order.
While not necessary, f2cl can do a significantly better job in While not necessary, f2cl can do a significantly better job in
generating code if the functions are compiled in the correct generating code if the functions are compiled in the correct
order. This means any function, F, that is called by another order. This means any function, F, that is called by another
......
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