[llvm] [InstCombine] Extend folding of aggregate construction to cases when source aggregates are partially available (PR #100828)

[via llvm-commits]

weiguozhi wrote:

Thanks for the quick test.

The new insertvalue is added to a predecessor with only one successor, so it intends to reduce the number of executed insertvalue instruction. But it doesn't behave like this when a loop is involved. The loop exiting edges and loop latches don't guarantee reduced dynamic number of insertvalue instructions. We should check these cases.

https://github.com/llvm/llvm-project/pull/100828