llvm-project

e947139f - [SDAG] Disable illegal extract_subvector splitting for scalable vectors (#170315)

[SDAG] Disable illegal extract_subvector splitting for scalable vectors (#170315) The "half spanning" legalization of extract_subvector is only valid for fixed-length vectors. This patch disables it for scalable vectors and makes more careful use of ElementCount in the lowering. Fixes regression from https://github.com/llvm/llvm-project/pull/154101, which was encountered here: https://github.com/llvm/llvm-project/pull/166748#issuecomment-3600498185 Note: We could optimize this case given the known vscale, but this patch only attempts to fix the miscompile.