Return a SwiftArrayEmptyBufferHandler if loc points to an EmptyArray Symbol. #10920
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…Symbol. If we have a ValueObjectSP who's storage_location points to a S_swiftEmptyArrayStorage symbol, return a SwiftArrayEmptyBufferHandler
| // a SwiftArrayEmptyBufferHandler. | ||
| if (auto *symbol = addr.CalculateSymbolContextSymbol()) { | ||
| auto mangledName = symbol->GetMangled().GetMangledName().GetStringRef(); | ||
| if (mangledName == "$ss19__EmptyArrayStorageCN") { |
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should this be _swiftEmptyArrayStorage?
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I am checking the mangled name:
> xcrun swift-demangle ss19__EmptyArrayStorageCN
$ss19__EmptyArrayStorageCN ---> type metadata for Swift.__EmptyArrayStorage
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When I inspect an empty array, I see:
(lldb) v -R -T -d no-dynamic-values
(Swift.Array<main.P>) x = {
(Swift._ArrayBuffer<main.P>) _buffer = {
(Swift._BridgeStorage<Swift.__ContiguousArrayStorageBase>) _storage = {
(Builtin.BridgeObject) rawValue = 0x00000001f52cd120 _swiftEmptyArrayStorage
}
}
}
I don't see where $ss19__EmptyArrayStorageCN comes into play. Also the PR description mentions _swiftEmptyArrayStorage but the changed code does not.
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This mangled name is for the type metadata for Swift.__EmptyArrayStorage.
- You probably want to match against
Swift.__EmptyArrayStorageitself. - Instead of depending on the mangling it would be better to use the helpers in SwiftDemangling.h to make sure you have the expected demangle tree for a class with the right name in STDLIB_MODULENAME.
| target, process, thread, breakpoint1 = lldbutil.run_to_source_breakpoint( | ||
| self, "break here", filespec | ||
| ) | ||
| self.expect("p x", substrs=["([a.P]) 0 values {}"]) |
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for tests we use frame var or expr to be explicit whether it's use expression evaluation or not.
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Even better would be
x = self.frame().FindVariable("x")
lldbutil.check_variable(self, x, summary="0 values")
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or self.assertEqual(x.GetSummary(), "0 values")
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| self.build() | ||
| filespec = lldb.SBFileSpec("main.swift") | ||
| target, process, thread, breakpoint1 = lldbutil.run_to_source_breakpoint( |
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| target, process, thread, breakpoint1 = lldbutil.run_to_source_breakpoint( | |
| lldbutil.run_to_source_breakpoint( |
| self.build() | ||
| filespec = lldb.SBFileSpec("main.swift") | ||
| target, process, thread, breakpoint1 = lldbutil.run_to_source_breakpoint( | ||
| self, "break here", filespec |
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| self, "break here", filespec | |
| self, "break here", lldb.SBFileSpec("main.swift") |
If we have a ValueObjectSP who's storage_location points to a
S_swiftEmptyArrayStoragesymbol, return aSwiftArrayEmptyBufferHandler