[DebugInfo] Support for DW_OP_LLVM_explicit_pointer (temp2reg).
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Authored by alok on Nov 28 2019, 11:25 AM.

Details

Reviewers

aprantl
probinson
dblaikie
jmorse
jini.susan.george
SouraVX
awpandey

Summary

Summary:

This enables debugger to display de-referenced value of pointer in case temporary is optimized out. It happens in case of reference. This patch need to include some compile time option to enable/disable.

Testing:

-Added unit test for validation thru llvm-dwarfdump
-check-llvm (LLDB need to be modifed to support this)
-check-debuginfo (the debug info integration tests)

Diff Detail

Event Timeline

alok created this revision.Nov 28 2019, 11:25 AM

Herald added subscribers: llvm-commits, ormris, hiraditya. · View Herald TranscriptNov 28 2019, 11:25 AM

alok added a parent revision: D69886: [DebugInfo] Support for DW_OP_implicit_pointer (CodeGen phase).Nov 28 2019, 11:26 AM

gbedwell added a subscriber: gbedwell.Nov 28 2019, 11:39 AM

Updated to rename proposed LLVM Dwarf extension to DW_OP_LLVM_explicit_pointer.

dblaikie added inline comments.Dec 4 2019, 11:21 AM

llvm/docs/LangRef.rst
4828–4829	I think this probably still needs some design discussion on the llvm-dev design thread (I know I'm mostly slacking there) - specifically the "can only appear at the beginning" seems like it misses the case I brought up on the thread about multiple levels of indirection.