[libFuzzer] Add support for Fuchsia OS.

Summary:
This patch adds the initial support for Fuchsia.

- LIBFUZZER_FUCHSIA is added as an OS type in FuzzerDefs.h
- Fuchsia is, by design, not POSIX compliant. However, it does use ELF and
  supports common POSIX I/O functions. Thus, FuzzerExtFunctions.h and
  FuzzerIO.h are implemented by extending the header guards in
  FuzzerExtFunctionsWeak.cpp and FuzzerIOPosix.cpp to include
  LIBFUZZER_FUCHSIA.
- The platform-specific portions of FuzzerUtil.h are implemented by
  FuzzerUtilFuchsia.cpp, which makes use of exception ports, syscalls, and
  the launchpad library.
- The experimental equivalence server is not currently supported, so
  FuzzerShmem.h is implemented by stub methods in FuzzerShmemFuchsia.cpp.
  Any future implementation will likely involve VMOs.

Tested with ASAN/SanCov on Fuchsia/x86-64 with the canonical toy fuzzer.

Patch By: aarongreen

Reviewers: kcc, morehouse, flowerhack, phosek

Reviewed By: kcc, phosek, Eugene.Zelenko

Subscribers: srhines, mgorny, Eugene.Zelenko

Differential Revision: https://reviews.llvm.org/D40974

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@320210 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/fuzzer/CMakeLists.txt b/lib/fuzzer/CMakeLists.txt
index e442b645e..9769be52a 100644
--- a/lib/fuzzer/CMakeLists.txt
+++ b/lib/fuzzer/CMakeLists.txt
@@ -18,6 +18,7 @@ set(LIBFUZZER_SOURCES
   FuzzerTracePC.cpp
   FuzzerUtil.cpp
   FuzzerUtilDarwin.cpp
+  FuzzerUtilFuchsia.cpp
   FuzzerUtilLinux.cpp
   FuzzerUtilPosix.cpp
   FuzzerUtilWindows.cpp