summaryrefslogtreecommitdiff
path: root/scripts/kconfig/internal.h
AgeCommit message (Collapse)Author
2024-09-20kconfig: cache expression valuesMasahiro Yamada
Cache expression values to avoid recalculating them repeatedly. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-09-20kconfig: use hash table to reuse expressionsMasahiro Yamada
Currently, every expression in Kconfig files produces a new abstract syntax tree (AST), even if it is identical to a previously encountered one. Consider the following code: config FOO bool "FOO" depends on (A || B) && C config BAR bool "BAR" depends on (A || B) && C config BAZ bool "BAZ" depends on A || B The "depends on" lines are similar, but currently a separate AST is allocated for each one. The current data structure looks like this: FOO->dep ==> AND BAR->dep ==> AND BAZ->dep ==> OR / \ / \ / \ OR C OR C A B / \ / \ A B A B This is redundant; FOO->dep and BAR->dep have identical ASTs but different memory instances. We can optimize this; FOO->dep and BAR->dep can share the same AST, and BAZ->dep can reference its sub tree. The optimized data structure looks like this: FOO->dep, BAR->dep ==> AND / \ BAZ->dep ==> OR C / \ A B This commit introduces a hash table to keep track of allocated expressions. If an identical expression is found, it is reused. This does not necessarily result in memory savings, as menu_finalize() transforms expressions without freeing up stale ones. This will be addressed later. One optimization that can be easily implemented is caching the expression's value. Once FOO's dependency, (A || B) && C, is calculated, it can be cached, eliminating the need to recalculate it for BAR. This commit also reverts commit e983b7b17ad1 ("kconfig/menu.c: fix multiple references to expressions in menu_add_prop()"). Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-07-21kbuild: move some helper headers from scripts/kconfig/ to scripts/include/Masahiro Yamada
Move array_size.h, hashtable.h, list.h, list_types.h from scripts/kconfig/ to scripts/include/. These headers will be useful for other host programs. Remove scripts/mod/list.h. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-02-20kconfig: use generic macros to implement symbol hashtableMasahiro Yamada
Use helper macros in hashtable.h for generic hashtable implementation. We can git rid of the hash head index of for_all_symbols(). Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-02-19kconfig: remove zconf_curname() and zconf_lineno()Masahiro Yamada
Now zconf_curname() and zconf_lineno() are so simple that they just return cur_filename, cur_lineno, respectively. Remove these functions, and then use cur_filename and cur_lineno directly. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-14kconfig: split menu.c out of parser.yMasahiro Yamada
Compile menu.c as an independent compilation unit. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>