[llvm] [IPSCCP] Variable not visible at Og. (PR #66745)

[Carlos Alberto Enciso via llvm-commits]

CarlosAlbertoEnciso wrote:

Thanks for all your comments.
Updated to address:
@dwblaikie: include unittests (Covering the most common types for constants).
@djtodoro and @nikic: reduce the lit test (Removing redundant `!dbg`).
@nikic: extra braces and different `if` condition for pointer types.

https://github.com/llvm/llvm-project/pull/66745