author | greg |
Wed, 26 Nov 2008 09:06:26 +0100 | |
changeset 152 | efc510145ab2 |
parent 67 | 08097122a922 |
child 265 | 4d222f46f8cc |
permissions | -rwxr-xr-x |
0
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
1 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
2 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
3 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
4 |
IEC 61131-3 IL and ST compiler |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
5 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
6 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
7 |
The following compiler has been based on the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
8 |
FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
9 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
10 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
11 |
(c) 2003 Mario de Sousa |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
12 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
13 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
14 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
15 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
16 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
17 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
18 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
19 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
20 |
********* O V E R A L L A R C H I T E C T U R E ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
21 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
22 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
23 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
24 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
25 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
26 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
27 |
The compiler works in 4(+1) stages: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
28 |
Stage 1 - Lexical analyser - implemented with flex (iec.flex) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
29 |
Stage 2 - Syntax parser - implemented with bison (iec.y) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
30 |
Stage 3 - Semantics analyser - not yet implemented |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
31 |
Stage 4 - Code generator - implemented in C++ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
32 |
Stage 4+1 - Binary code generator - gcc, javac, etc... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
33 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
34 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
35 |
Data structures passed between stages, in global variables: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
36 |
1->2 : tokens (int), and token values (char *) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
37 |
2->1 : symbol tables (defined in symtable.hh) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
38 |
2->3 : abstract syntax tree (tree of C++ classes, in absyntax.hh file) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
39 |
3->4 : Same as 2->3 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
40 |
4->4+1 : file with program in c, java, etc... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
41 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
42 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
43 |
The compiler works in several passes: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
44 |
Pass 1: executes stages 1 and 2 simultaneously |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
45 |
Pass 2: executes stage 3 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
46 |
Pass 3: executes stage 4 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
47 |
Pass 4: executes stage 4+1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
48 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
49 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
50 |
NOTE 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
51 |
====== |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
52 |
Note that stage 2 passes data back to stage 1. This is only |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
53 |
possible because both stages are executed in the same pass. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
54 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
55 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
56 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
57 |
NOTE 2 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
58 |
====== |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
59 |
I (Mario) have a feeling that the abstract syntax may be |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
60 |
considerably simplified without any drawbacks to semantic checking |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
61 |
and code generation. I have nevertheless opted to keep as much |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
62 |
info as possible in the abstract syntax tree, in case it may become |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
63 |
necessary further on. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
64 |
Once we start coding the next stages (semantic checking and code |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
65 |
generation) I will get a better understanding of what is required |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
66 |
of the abstract syntax tree. At that stage I will be better |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
67 |
positioned to make a more informed decision on how best to structure |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
68 |
the abstract syntax tree. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
69 |
For now, we play conservative and keep as much info as possible. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
70 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
71 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
72 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
73 |
NOTE 3 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
74 |
====== |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
75 |
It would be nice to get this parser integrated into the gcc |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
76 |
group of compilers. We would then be able to compile our st/il |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
77 |
programs directly into executable binaries, for all the processor |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
78 |
architectures gcc currently supports. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
79 |
The gcc compilers are divided into a frontend and backend. The |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
80 |
data structure between these two stages is called the syntax |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
81 |
tree. In essence, we would need to create a new frontend that |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
82 |
would parse the st/il program and build the syntax tree. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
83 |
Unfortunately the gcc syntax tree is not very well documented, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
84 |
and doing semantic checking on this tree would probably be a |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
85 |
nightmare. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
86 |
We therefore chose to follow the same route as the gnat (ada 95) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
87 |
and cobol compilers, i.e. generate our own abstract syntax tree, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
88 |
do semantic checking on our tree, do whatever optimisation |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
89 |
we can at this level on our own tree, and only then build |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
90 |
the gcc syntax tree from our abstract syntax tree. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
91 |
All this may still be integrated with the gcc backend to generate |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
92 |
a new gnu compiler for the st and il programming languages. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
93 |
Since generating the gcc syntax tree will probably envolve some |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
94 |
trial and error effort due to the sparseness of documentation, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
95 |
we chose to start off by coding a C++ code generator for |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
96 |
our stage 4. We may later implement a gcc syntax tree generator |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
97 |
as an alternative stage 4 process, and then integrate it with |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
98 |
the gcc toplevel.c file (command line parsing, etc...). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
99 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
100 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
101 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
102 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
103 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
104 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
105 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
106 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
107 |
********* S T A G E 1 ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
108 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
109 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
110 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
111 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
112 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
113 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
114 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
115 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
116 |
Issue 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
117 |
======= |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
118 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
119 |
The syntax defines the common_character_representation as: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
120 |
<any printable character except '$', '"' or "'"> | <escape sequences> |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
121 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
122 |
Flex includes the function print_char() that defines |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
123 |
all printable characters portably (i.e. whatever character |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
124 |
encoding is currently being used , ASCII, EBCDIC, etc...) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
125 |
Unfortunately, we cannot generate the definition of |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
126 |
common_character_representation portably, since flex |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
127 |
does not allow definition of sets by subtracting |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
128 |
elements in one set from another set (Note how |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
129 |
common_character_representation could be defined by |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
130 |
subtracting '$' '"' and "'" from print_char() ). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
131 |
This means we must build up the defintion of |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
132 |
common_character_representation using only set addition, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
133 |
which leaves us with the only choice of defining the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
134 |
characters non-portably... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
135 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
136 |
In short, the definition we use for common_character_representation |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
137 |
only works for ASCII character encoding! |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
138 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
139 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
140 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
141 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
142 |
Issue 2 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
143 |
======= |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
144 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
145 |
We extend the IEC 61131-3 standard syntax to allow inclusion of |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
146 |
other files. The accepted syntax is: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
147 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
148 |
(*#include "<filename>" *) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
149 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
150 |
Note how this would be ignored by other standard complient compilers |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
151 |
as a simple comment! |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
152 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
153 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
154 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
155 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
156 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
157 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
158 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
159 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
160 |
********* S T A G E 2 ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
161 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
162 |
********* ********* |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
163 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
164 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
165 |
**************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
166 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
167 |
Overall Comments |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
168 |
================ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
169 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
170 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
171 |
Comment 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
172 |
--------- |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
173 |
We have augmented the syntax the specification defines to include |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
174 |
restrictions defined in the semantics of the languages. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
175 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
176 |
This is required because the syntax cannot be parsed by a LALR(1) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
177 |
parser as it is presented in the specification. Many reduce/reduce |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
178 |
and shift/reduce conflicts arise. This is mainly because the parser |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
179 |
cannot discern how to reduce an identifier. Identifiers show up in |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
180 |
many places in the syntax, and it is not entirely possible to |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
181 |
figure out if the identifier is a variable_name, enumeration |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
182 |
value, function block name, etc... only from the context in |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
183 |
which it appears. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
184 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
185 |
A more detailed example of why we need symbol tables are |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
186 |
the type definitions... In definition of new types |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
187 |
(section B 1.3.3) the parser needs to figure out the class of |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
188 |
the new type being defined (enumerated, structure, array, etc...). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
189 |
This works well when the base classes are elementary types |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
190 |
(or structures, enumeration, arrays, etc. thereof). It becomes |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
191 |
confusing to the parser when the new_type is based on a previously |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
192 |
user defined type. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
193 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
194 |
TYPE |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
195 |
new_type_1 : INT := 99; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
196 |
new_type_2 : new_type_1 := 100; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
197 |
END_TYPE |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
198 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
199 |
When parsing new_type_1, the parser can figure out that the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
200 |
identifier new_type_1 is a simple_type_name, because it is |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
201 |
based on a elementary type without structure, arrays, etc... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
202 |
While parsing new_type_2, it becomes confused how to reduce |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
203 |
the new_type_2 identifier, as it is based on the identifier |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
204 |
new_type_1, of which it does not know the class (remember, at this |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
205 |
stage new_type_1 is a simple identifier!). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
206 |
We therefore need to keep track of the class of the user |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
207 |
defined types as they are declared, so that the lexical analyser |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
208 |
can tell the syntax parser what class the type belongs to. We |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
209 |
cannot use the abstract syntax tree itself to search for the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
210 |
declaration of new_type_1 as we only get a handle to the root |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
211 |
of the tree at the end of the parsing. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
212 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
213 |
We therefore maintain an independent and parallel table of symbols, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
214 |
that is filled as we come across the type delcarations in the code. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
215 |
Actually, we ended up also needing to store variable names in |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
216 |
the symbol table. Since variable names come and go out of scope |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
217 |
depending on what portion of code we are parsing, we sometimes |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
218 |
need to remove the variable names from the symbol table. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
219 |
Since the ST and IL languages only have a single level of scope, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
220 |
I (Mario) found it easier to simply use a second symbol table for |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
221 |
the variable names that is completely cleared when the parser |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
222 |
reaches the end of a function (function block or program). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
223 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
224 |
What I mean when I say that these languages have a single level |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
225 |
of scope is that all variables used in a function (function block |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
226 |
or program) must be declared inside that function (function block |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
227 |
or program). Even global variables must be re-declared as EXTERN |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
228 |
before a function may access them! This means that it is easy |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
229 |
to simply load up the variable name symbol table when we start |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
230 |
parsing a function (function block or program), and to clear it |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
231 |
when we reach the end. Checking whether variables declared |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
232 |
as EXTERN really exist inside a RESOURCE or a CONFIGURATION |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
233 |
is left to stage 3 (semantic checking) where we can use the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
234 |
abstract tree itself to search for the variables (NOTE: semantic |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
235 |
cheching at stage 3 has not yet been implemented, so we may yet |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
236 |
end up using a symbol table too at that stage!). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
237 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
238 |
Due to the use of the symbol tables, and special identifier |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
239 |
tokens depending on the type of identifier it had previously |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
240 |
been declared in the code being parsed, the syntax was slightly |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
241 |
changed regarding the definition of variable names, derived |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
242 |
function names, etc... FROM for e.g.: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
243 |
variable_name: identifier; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
244 |
TO |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
245 |
variable_name: variable_name_token; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
246 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
247 |
Flex first looks at the symbol tables when it finds an identifier, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
248 |
and returns the correct token corresponding to the identifier |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
249 |
type in question. Only if the identifier is not currently stored |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
250 |
in any symbol table, does flex return a simple identifier_token. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
251 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
252 |
This means that the declarations of variables, functions etc... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
253 |
were changed FROM: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
254 |
function_declaration: FUNCTION derived_function_name ... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
255 |
TO |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
256 |
function_declaration: FUNCTION identifier ... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
257 |
since the initial definition of derived_function_name had been |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
258 |
changed FROM |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
259 |
derived_function_name: identifier; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
260 |
TO |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
261 |
derived_function_name: derived_function_name_token; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
262 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
263 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
264 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
265 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
266 |
Comment 2 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
267 |
--------- |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
268 |
Since the ST and IL languages share a lot of common syntax, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
269 |
I have decided to write a single parser to handle both languages |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
270 |
simultaneously. This approach has the advantage that the user |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
271 |
may mix the language used in the same file, as long as each function |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
272 |
is written in a single lanuage. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
273 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
274 |
This approach also assumes that all the IL language operators are |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
275 |
keywords, which means that it is not possible to define variables |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
276 |
using names such as "LD", "ST", etc... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
277 |
Note that the spec does not consider these operators to be keywords, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
278 |
so it means that they should be available for variable names! On the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
279 |
other hand, all implementations of the ST and IL languages seems to |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
280 |
treat them as keywords, so there is not much harm in doing the same. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
281 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
282 |
If it ever becomes necessary to allow variables with names of IL |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
283 |
operators, either the syntax will have to be augmented, or we can |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
284 |
brake up the parser in two: one for ST and another for IL. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
285 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
286 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
287 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
288 |
/********************************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
289 |
/* B 1.3.3 - Derived data types */ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
290 |
/********************************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
291 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
292 |
Issue 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
293 |
======= |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
294 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
295 |
According to the spec, the valid construct |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
296 |
TYPE new_str_type : STRING := "hello!"; END_TYPE |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
297 |
has two possible routes to type_declaration... |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
298 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
299 |
Route 1: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
300 |
type_declaration: single_element_type_declaration |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
301 |
single_element_type_declaration: simple_type_declaration |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
302 |
simple_type_declaration: identifier ':' simple_spec_init |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
303 |
simple_spec_init: simple_specification ASSIGN constant |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
304 |
(shift: identifier <- 'new_str_type') |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
305 |
simple_specification: elementary_type_name |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
306 |
elementary_type_name: STRING |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
307 |
(shift: elementary_type_name <- STRING) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
308 |
(reduce: simple_specification <- elementary_type_name) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
309 |
(shift: constant <- "hello!") |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
310 |
(reduce: simple_spec_init: simple_specification ASSIGN constant) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
311 |
(reduce: ...) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
312 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
313 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
314 |
Route 2: |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
315 |
type_declaration: string_type_declaration |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
316 |
string_type_declaration: identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
317 |
(shift: identifier <- 'new_str_type') |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
318 |
elementary_string_type_name: STRING |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
319 |
(shift: elementary_string_type_name <- STRING) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
320 |
(shift: string_type_declaration_size <- /* empty */) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
321 |
string_type_declaration_init: ASSIGN character_string |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
322 |
(shift: character_string <- "hello!") |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
323 |
(reduce: string_type_declaration_init <- ASSIGN character_string) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
324 |
(reduce: string_type_declaration <- identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init ) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
325 |
(reduce: type_declaration <- string_type_declaration) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
326 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
327 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
328 |
At first glance it seems that removing route 1 would make |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
329 |
the most sense. Unfortunately the construct 'simple_spec_init' |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
330 |
shows up multiple times in other rules, so changing this construct |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
331 |
would mean changing all the rules in which it appears. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
332 |
I (Mario) therefore chose to remove route 2 instead. This means |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
333 |
that the above declaration gets stored in a |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
334 |
simple_type_declaration_c, and not in a string_type_declaration_c |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
335 |
as would be expected! |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
336 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
337 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
338 |
/***********************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
339 |
/* B 1.5.1 - Functions */ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
340 |
/***********************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
341 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
342 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
343 |
Issue 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
344 |
======= |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
345 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
346 |
Due to reduce/reduce conflicts between identifiers |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
347 |
being reduced to either a variable or an enumerator value, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
348 |
we were forced to keep a symbol table of the names |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
349 |
of all declared variables. Variables are no longer |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
350 |
created from simple identifier_token, but from |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
351 |
variable_name_token. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
352 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
353 |
BUT, in functions the function name may be used as |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
354 |
a variable! In order to be able to parse this correctly, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
355 |
the token parser (flex) must return a variable_name_token |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
356 |
when it comes across the function name, while parsing |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
357 |
the function itself. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
358 |
We do this by inserting the function name into the variable |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
359 |
symbol table, and having flex return a variable_name_token |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
360 |
whenever it comes across it. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
361 |
When we finish parsing the function the variable name |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
362 |
symbol table is cleared of all entries, and the function |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
363 |
name is inserted into the library element symbol table. This |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
364 |
means that from then onwards flex will return a |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
365 |
derived_function_name_token whenever it comes across the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
366 |
function name. |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
367 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
368 |
In order to insert the function name into the variable_name |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
369 |
symbol table BEFORE the function body gets parsed, we |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
370 |
need the parser to reduce a construct that contains the |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
371 |
the function name. That is why we created the extra |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
372 |
construct 'function_name_declaration', i.e. to force |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
373 |
the parser to reduce it, before parsing the function body, |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
374 |
and therefore get an oportunity to insert the function name |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
375 |
into the variable name symbol table! |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
376 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
377 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
378 |
/********************************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
379 |
/* B 3.2.4 Iteration Statements */ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
380 |
/********************************/ |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
381 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
382 |
Issue 1 |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
383 |
======= |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
384 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
385 |
For the 'FOR' iteration loop |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
386 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
387 |
FOR control_variable ASSIGN expression TO expression BY expression DO statement_list END_FOR |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
388 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
389 |
The spec declares the control variable in the syntax as |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
390 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
391 |
control_variable: identifier; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
392 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
393 |
but then defines the semantics of control_variable (Section 3.3.2.4) |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
394 |
as being of an integer type (e.g., SINT, INT, or DINT). |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
395 |
Obviously this presuposes that the control_variable must have been |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
396 |
declared in some 'VAR .. VAR_END' construct, so I (Mario) changed |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
397 |
the syntax to read |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
398 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
399 |
control_variable: variable_name; |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
400 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
401 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
402 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
403 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
404 |
************************************************************************** |
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
405 |
|
fb772792efd1
Initial commit. Last MatPLC CVS with some makefile inclusion removed in order to compile fine out of MatPLC.
etisserant
parents:
diff
changeset
|
406 |
(c) 2003 Mario de Sousa |