[DAG] Avoid deleting nodes before combining them.
When replacing a node and it's operand, replacing the operand node may
cause the deletion of the original node leading to an assertion
failure. Case around these replacements to avoid this without relying
on inspecting the DELETED_NODE opcode in various extend
dagcombiner cases.
Fixes PR32515.
Reviewers: dbabokin, RKSimon, davide, chandlerc
Subscribers: chandlerc, llvm-commits
Differential Revision: https://reviews.llvm.org/D34095
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308330 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed