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Speed up testing for multiple functions at an address on Posix

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The way this was originally written blows up on large enough targets
(like...Chromium :/). This change adds a set for amortized constant
time lookup of whether a FUNC already exists at a given address.

Bug: google-breakpad:751
Change-Id: I10a322da70f769c106e1e5f5b2dc3dc3f79444fd
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/4031580
Reviewed-by: Mark Mentovai <mark@chromium.org>
This commit is contained in:
Leonard Grey 2022-11-17 11:37:26 -05:00
parent 442456a68c
commit 522bd2337a
2 changed files with 15 additions and 17 deletions
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30
src/common/module.cc
View file

@ -174,26 +174,22 @@ bool Module::AddFunction(Function* function) {
}
}
#endif
if (enable_multiple_field_) {
if (enable_multiple_field_ && function_addresses_.count(function->address)) {
FunctionSet::iterator existing_function = std::find_if(
functions_.begin(), functions_.end(),
[&](Function* other) { return other->address == function->address; });
if (existing_function != functions_.end()) {
(*existing_function)->is_multiple = true;
// Free the duplicate that was not inserted because this Module
// now owns it.
return false;
}
std::pair<FunctionSet::iterator, bool> ret = functions_.insert(function);
// We just checked!
assert(ret.second);
} else {
std::pair<FunctionSet::iterator, bool> ret = functions_.insert(function);
if (!ret.second && (*ret.first != function)) {
// Free the duplicate that was not inserted because this Module
// now owns it.
return false;
}
assert(existing_function != functions_.end());
(*existing_function)->is_multiple = true;
// Free the duplicate that was not inserted because this Module
// now owns it.
return false;
}
function_addresses_.emplace(function->address);
std::pair<FunctionSet::iterator, bool> ret = functions_.insert(function);
if (!ret.second && (*ret.first != function)) {
// Free the duplicate that was not inserted because this Module
// now owns it.
return false;
}
return true;
}

2
src/common/module.h
View file

@ -472,6 +472,8 @@ class Module {
// point to.
FileByNameMap files_; // This module's source files.
FunctionSet functions_; // This module's functions.
// Used to quickly look up whether a function exists at a particular address.
unordered_set<Address> function_addresses_;
// The module owns all the call frame info entries that have been
// added to it.