[lldb] [ObjectFileMachO] LLVM_COV is not mapped into firmware memory (#86359) #8476
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…lvm#86359) It is possible to gather code coverage in a firmware environment, where the __LLVM_COV segment will not be mapped in memory but does exist in the binary, see https://llvm.org/devmtg/2020-09/slides/PhippsAlan_EmbeddedCodeCoverage_LLVM_Conf_Talk_final.pdf The __LLVM_COV segment in the binary happens to be at the same address as the __DATA segment, so if lldb treats this segment as loaded, it shadows the __DATA segment and address->symbol resolution can fail. For these non-userland code cases, we need to mark __LLVM_COV as not a loadable segment. rdar://124475661 (cherry picked from commit 765d4c4)
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It is possible to gather code coverage in a firmware environment, where the __LLVM_COV segment will not be mapped in memory but does exist in the binary, see
https://llvm.org/devmtg/2020-09/slides/PhippsAlan_EmbeddedCodeCoverage_LLVM_Conf_Talk_final.pdf
The __LLVM_COV segment in the binary happens to be at the same address as the __DATA segment, so if lldb treats this segment as loaded, it shadows the __DATA segment and address->symbol resolution can fail.
For these non-userland code cases, we need to mark __LLVM_COV as not a loadable segment.
rdar://124475661
(cherry picked from commit 765d4c4)