search for: selectiondag_leg

I cannot understand what does the paragraph mean. Could anyone please elaborate it? http://llvm.cs.uiuc.edu/ChrisLLVM/docs/CodeGenerator.html#selectiondag_legalize "Instead of using a Legalize pass, we could require that every target-specific selector supports and expands every operator and type even if they are not supported and may require many instructions to implement (in fact, this is the approach taken by the "simple" selectors). Ho...

...ing to the type of any node, it is referring to the extra data held in the VALUETYPE node argument of the SEXTLOAD node. are used to eliminate any operations that are unsupported > on the target in Legalize phase after then LegalizeType phase. > (http://llvm.org/docs/**CodeGenerator.html#**selectiondag_legalize<http://llvm.org/docs/CodeGenerator.html#selectiondag_legalize> > ) > Do I misunderstand any concept here? > Ciao, Duncan. > > Best regards, > > Zakk > > > > > 2011/9/3 Duncan Sands <baldrick at free.fr <mailto:baldrick at free.fr>> >...

Hi, all I am studying the ARM backend on SelectionDAG, I have some following questions: 1. Each operator of SDNode in SelectionDAG is required to be defined by SDNode<ISD::XXX,XXX,XXX> in .td file, right? But several operators are not defined in .td file, why? (e.g., ISD::BR_CC, ISD::CopyToReg, ISD::AssertSext) 2. The MVT::glue value is used to ensure two nodes are scheduled