[clang] [clang] Use File Location for debug info resolution. (PR #163982)

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SergejSalnikov wrote:

I can tackle the 
> The .debug_line size will inevitably increase. Does this noticeably impact file size of say, a clang self host build?

When compiling in without full debug info the size difference of binary is under 0.01%
When using `-g` option, the binary size is impacted by less than 0.5% while the debug symbols size is around 8% for macro heavy code-bases.

But usually the reason to compile the binary with `-g` option is to have move debug info, not less. Why do we treat macro any different from other code.
If the goal is to save on symbols size, we can always fold all source locations to a single line .


https://github.com/llvm/llvm-project/pull/163982