swift

2dbf54da - [ome] Just erase the destructure rather than trying to get rid of dead instructions due to simplifyInstruction.

[ome] Just erase the destructure rather than trying to get rid of dead instructions due to simplifyInstruction. This ensures that we do not run into any iterator invalidation issues. It does worsen the passes output slightly, but avoiding the complexity is worth it and other later passes will clean up the dead code. rdar://55811732 (cherry picked from commit 1b29d860b8164b2c9927d49ee86923faf3fae766)