Reverts the [revert](https://github.com/llvm/llvm-project/pull/151424)
and fixed some typos.
Original PR description:
Second attempt to fix
https://discourse.llvm.org/t/rfc-new-dwarf-attribute-for-symbolication-of-merged-functions/79434/29?u=alx32
(First attempt: https://github.com/llvm/llvm-project/pull/143656)
Context: the sequence offset to row index we parsed may not be complete.
And we need to add manual matching to it.
https://github.com/llvm/llvm-project/pull/143656 attempts to do trivial
1:1 matching, however, sometimes they don't line up perfectly, as shown
below:
// While SeqOffToOrigRow parsed from CU could be the ground truth,
// e.g.
//
// SeqOff Row
// 0x08 9
// 0x14 15
//
// The StmtAttrs and SeqStartRows may not match perfectly, e.g.
//
// StmtAttrs SeqStartRows
// 0x04 3
// 0x08 5
// 0x10 9
// 0x12 11
// 0x14 15
//
// In this case, we don't want to assign 5 to 0x08, since we know 0x08
// maps to 9. If we do a dummy 1:1 mapping 0x10 will be mapped to 9
// which is incorrect. The expected behavior is ignore 5, realign the
// table based on the result from the line table:
//
// StmtAttrs SeqStartRows
// 0x04 3
// -- 5
// 0x08 9 <- LineTableMapping ground truth
// 0x10 11
// 0x12 --
// 0x14 15 <- LineTableMapping ground truth
In this case, we need to use the mapping we read from the line table as
a ground truth and organize them properly to prevent duplicated
offset/missing offset.
Test:
Updated the test case
---------
Signed-off-by: Peter Rong <PeterRong@meta.com>
Co-authored-by: Ellis Hoag <ellis.sparky.hoag@gmail.com>
fe899cedac