Displaying 1 result from an estimated 1 matches for "6d8e3c63".
Did you mean:
68e3863
2015 Jul 31
1
[LLVMdev] PerformDAGCombine vs. DAG to DAG
Hello LLVM,
If there are any, can someone please explain rules of thumb for when
to do a PerformDAGCombine operation in ISelLowering vs. when to do a
DAG to DAG transformation?
I'm specifically thinking of an AND + SRL merge into a bit field
extract type instruction. I see that the ARM target does this in
DAG-to-DAG, but this is literally a combine of two instructions,so why
not DAGCombine?