[llvm] [StackSafetyAnalysis] Don't call getTruncateOrZeroExtend for pointers of different sizes (PR #79804)

[Nikita Popov via llvm-commits]

nikic wrote:

I've added a regression test for the pointer assertion failure in https://github.com/llvm/llvm-project/commit/4c2422e56ef17ca113be160cf85672c4736bc11e. The pass is blindly following all instruction uses in https://github.com/llvm/llvm-project/blob/4c2422e56ef17ca113be160cf85672c4736bc11e/llvm/lib/Analysis/StackSafetyAnalysis.cpp#L524-L525, while it should only be following bitcast / GEP and bailing out on everything else.

https://github.com/llvm/llvm-project/pull/79804