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-rw-r--r--filter/f-inst.h34
1 files changed, 1 insertions, 33 deletions
diff --git a/filter/f-inst.h b/filter/f-inst.h
index 58a60f0f..33fcf4a9 100644
--- a/filter/f-inst.h
+++ b/filter/f-inst.h
@@ -7,39 +7,7 @@
* Can be freely distributed and used under the terms of the GNU GPL.
*
* Filter interpreter data structures and internal API.
- * The filter code goes through several phases:
- *
- * 1 Parsing
- * Flex- and Bison-generated parser decodes the human-readable data into
- * a struct f_inst tree. This is an infix tree that was interpreted by
- * depth-first search execution in previous versions of the interpreter.
- * All instructions have their constructor: f_new_inst(FI_code, ...)
- * translates into f_new_inst_FI_code(...) and the types are checked in
- * compile time.
- *
- * 2 Linearize before interpreting
- * The infix tree is always interpreted in the same order. Therefore we
- * sort the instructions one after another into struct f_line. Results
- * and arguments of these instructions are implicitly put on a value
- * stack; e.g. the + operation just takes two arguments from the value
- * stack and puts the result on there.
- *
- * 3 Interpret
- * The given line is put on a custom execution stack. If needed (FI_CALL,
- * FI_SWITCH, FI_AND, FI_OR, FI_CONDITION, ...), another line is put on top
- * of the stack; when that line finishes, the execution continues on the
- * older lines on the stack where it stopped before.
- *
- * 4 Same
- * On config reload, the filters have to be compared whether channel
- * reload is needed or not. The comparison is done by comparing the
- * struct f_line's recursively.
- *
- * The main purpose of this rework was to improve filter performance
- * by making the interpreter non-recursive.
- *
- * The other outcome is concentration of instruction definitions to
- * one place -- filter/f-inst.c
+ * See filter/f-inst.c for documentation.
*/
#ifndef _BIRD_F_INST_H_