forked from OSchip/llvm-project
bb54bcf849
The CrossOver mutator is meant to cross over two given buffers (referred to as
the first/second buffer henceforth). Previously InsertPartOf/CopyPartOf calls
used in the CrossOver mutator incorrectly inserted/copied part of the second
buffer into a "scratch buffer" (MutateInPlaceHere of the size
CurrentMaxMutationLen), rather than the first buffer. This is not intended
behavior, because the scratch buffer does not always (i) contain the content of
the first buffer, and (ii) have the same size as the first buffer;
CurrentMaxMutationLen is typically a lot larger than the size of the first
buffer. This patch fixes the issue by using the first buffer instead of the
scratch buffer in InsertPartOf/CopyPartOf calls.
A FuzzBench experiment was run to make sure that this change does not
inadvertently degrade the performance. The performance is largely the same; more
details can be found at:
https://storage.googleapis.com/fuzzer-test-suite-public/fixcrossover-report/index.html
This patch also adds two new tests, namely "cross_over_insert" and
"cross_over_copy", which specifically target InsertPartOf and CopyPartOf,
respectively.
- cross_over_insert.test checks if the fuzzer can use InsertPartOf to trigger
the crash.
- cross_over_copy.test checks if the fuzzer can use CopyPartOf to trigger the
crash.
These newly added tests were designed to pass with the current patch, but not
without the it (with
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| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
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| LICENSE.TXT | ||
| README.txt | ||
README.txt
Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================