[lldb][FrameRecognizer] Make VerboseTrapFrameRecognizer aware of Swift-C++ interop frames #9306
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…t-C++ interop frames
| static bool ShouldHideSwiftFrame(llvm::StringRef frame_name) { | ||
| static llvm::SmallVector<RegularExpression, 2> s_patterns{ | ||
| RegularExpression{R"(^(__C\.)?std\.)"}, | ||
| RegularExpression{R"(protocol witness for Cxx\.)"}}; |
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Would it be theoretically possible to have the Swift hidden frame recognizer take over in this case? It seems wrong to maintain this list in two places.
| if (auto module_node = ChildAtPath(witness_node, {Node::Kind::Module}); | ||
| module_node && module_node->getText() == "__C_Synthesized") | ||
| return true; | ||
| ; |
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FYI, maybe it'd be okay to remove all protocol witnesses.
| // prefix for functions from libc++. We don't want to | ||
| // stop in those frames either. | ||
| && !frame_name.GetStringRef().starts_with("__C.std.") && | ||
| !frame_name.GetStringRef().starts_with("std.") |
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shouldn't this check live inside SwiftHiddenFrameRecognizer(), assuming that we never want to stop there?
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Depends, do we want to hide all frames from the std module? With C++ interop that could make sense. But wasn't sure.
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| @swiftTest | ||
| def test(self): | ||
| self.build() |
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Why not just do:
lldbutil.run_to_source_breakpoint(self, "Break here", lldb.SBFileSpec("main.swift")
?
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Is it because we don't expect tp hit the breakpoint?
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Yup, lldbutil.run_to_source_breakpoint asserts that we stopped at some breakpoint. Which won't happen for this test.
Might be worth creating a wrapper for the "just launch the executable" case. That way we could make use of __buitin_debugtrap in more tests too.
| // check the namespace prefix too. | ||
| if (!frame_name.GetStringRef().starts_with("std::") && | ||
| !most_relevant_frame_sp->IsHidden() | ||
| #ifdef LLDB_ENABLE_SWIFT |
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Can this live in the language plugin? The goal is to reduce the amount of changes in generic (non-Swift specific) code and we definitely don't want to add more.
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Argh forgot to squash the commits... |
This patch ensures that if
libc++is called from Swift (via Swift interop for example), and triggers a__builtin_verbose_trap, we don't stop in the Swift-C++ compiler-generated shims.E.g., in the example test-case, the stacktrace looks like:
We want to stop in frame 5, which is where the call into
stdstarted.rdar://136357737