Add support for SourceLocExpr

[Ukilele]

The following input:

auto X = __builtin_LINE();

generates following output:

unsigned int X = /* INSIGHTS-TODO: CodeGenerator.cpp:3851 stmt: SourceLocExpr */;

According to https://docs.hdoc.io/hdoc/llvm-project/r728584FDD0102CEF.html the class SourceLocExpr represents a function call to one of __builtin_LINE(), __builtin_COLUMN(), __builtin_FUNCTION(), __builtin_FILE(), or __builtin_source_location().
Especially with the C++20 std::source_location it would be neat if cppinsights would support this.

Best regards!

[andreasfertig]

Hello @Ukilele,

thanks for bringing this up.

I don't understand what role std::source_location plays here. You're using the internals required to implement source_location; the STD type works fine as far as I know.

I'm a bit reluctant to implement this transformation. Getting the correct information from SourceLocExpr seems difficult, and I'm unsure about the benefit.

Andreas

[Ukilele]

Hi Andreas,
your welcome!

I just brought up std::source_location because this was the class I originally used when I came accross this issue. I guess that since it's standarized since C++20, its usage might be higher than the one of builtin compiler-intrinsics. For a simplification of the code to reproduce the issue, I switched to __builtin_LINE().
When using std::source_location::current() you will get a similar output:

std::source_location::current(/* INSIGHTS-TODO: CodeGenerator.cpp:3851 stmt: SourceLocExpr */)

I agree that it definitely is no urgent or important issue.

[andreasfertig]

Hello @Ukilele,

usually I appreciate reduced issue reports, as I did here. Yet, your new std::source_location::current() reminded me of the implementation of source_location. Despite the standard not mentioning it, current takes a parameter of from __builtin_source_location. Looks like I have to act on this one :-)

Andreas

[Ukilele]

Awesome, that was quick :) Thanks a lot 👍