Massively speed up U-Boot parsing

U-Boot has a ton of definition locations for some symbols, causing a lot
of redundant work when iterating over Kconfig.defined_syms in
_build_dep(). Iterate over set(Kconfig.defined_syms) instead, wherever
possible.

This speeds up the U-Boot parsing time from 4 seconds to 0.6 seconds on
my machine.

Also update the bundled tools to iterate over set(Kconfig.defined_syms).
The performance loss is negligible even for projects that don't use
multiple definition locations.

Update the documentation to clarify that symbols/choices defined in
multiple locations appear multiple times in Kconfig.defined_syms/choices
as well.

1 files changed, 3 insertions, 1 deletions

diff --git a/allnoconfig.py b/allnoconfig.py
index d6ab701..173bf3f 100755
--- a/allnoconfig.py
+++ b/allnoconfig.py
@@ -31,7 +31,9 @@ def main():
     #    symbol types, which is what we want.
     kconf.disable_warnings()
 
-    for sym in kconf.defined_syms:
+    # The set() speeds things up for projects that use multiple definition
+    # locations a lot
+    for sym in set(kconf.defined_syms):
         sym.set_value(2 if sym.is_allnoconfig_y else 0)
 
     kconf.write_config(kconfiglib.standard_config_filename())