[llvm] r177477 - Mark all variable shifts needing customizing

[Michael Liao]

sure, I will add them asap. - michael

On Tue, 2013-03-19 at 21:21 -0700, Nadav Rotem wrote:
> Michael, 
> 
> 
> The TargetTransformInfo depends on the OpActions table for determining
> the costs of instructions. It assumes that the cost of 'legal'
> operation is lower than the cost of custom operations. When we mark
> everything as custom then TTI has no way of estimating the cost of
> operations without using the cost tables. I understand that your
> change is needed in order to move logic from DAGCombine to the
> Lowering phase, and generally this is a good change.  Can you please
> take a look at the cost tables and make sure that we did not miss
> anything due to this change?
> 
> 
> Thanks,
> Nadav
>  
> 
> 
> 
> On Mar 19, 2013, at 7:28 PM, Michael Liao <michael.liao at intel.com>
> wrote:
> 
> > Author: hliao
> > Date: Tue Mar 19 21:28:20 2013
> > New Revision: 177477
> > 
> > URL: http://llvm.org/viewvc/llvm-project?rev=177477&view=rev
> > Log:
> > Mark all variable shifts needing customizing
> > 
> > - Prepare moving logic from DAG combining into DAG lowering. There's
> > no
> >  functionality change.
> > 
> > 
> > Modified:
> >    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
> > 
> > Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=177477&r1=177476&r2=177477&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
> > +++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Tue Mar 19
> > 21:28:20 2013
> > @@ -1053,23 +1053,16 @@ X86TargetLowering::X86TargetLowering(X86
> >     setOperationAction(ISD::SRA,               MVT::v8i16, Custom);
> >     setOperationAction(ISD::SRA,               MVT::v16i8, Custom);
> > 
> > -    if (Subtarget->hasInt256()) {
> > -      setOperationAction(ISD::SRL,             MVT::v2i64, Legal);
> > -      setOperationAction(ISD::SRL,             MVT::v4i32, Legal);
> > -
> > -      setOperationAction(ISD::SHL,             MVT::v2i64, Legal);
> > -      setOperationAction(ISD::SHL,             MVT::v4i32, Legal);
> > +    // In the customized shift lowering, the legal cases in AVX2
> > will be
> > +    // recognized.
> > +    setOperationAction(ISD::SRL,               MVT::v2i64, Custom);
> > +    setOperationAction(ISD::SRL,               MVT::v4i32, Custom);
> > 
> > -      setOperationAction(ISD::SRA,             MVT::v4i32, Legal);
> > -    } else {
> > -      setOperationAction(ISD::SRL,             MVT::v2i64, Custom);
> > -      setOperationAction(ISD::SRL,             MVT::v4i32, Custom);
> > +    setOperationAction(ISD::SHL,               MVT::v2i64, Custom);
> > +    setOperationAction(ISD::SHL,               MVT::v4i32, Custom);
> > 
> > -      setOperationAction(ISD::SHL,             MVT::v2i64, Custom);
> > -      setOperationAction(ISD::SHL,             MVT::v4i32, Custom);
> > +    setOperationAction(ISD::SRA,               MVT::v4i32, Custom);
> > 
> > -      setOperationAction(ISD::SRA,             MVT::v4i32, Custom);
> > -    }
> >     setOperationAction(ISD::SDIV,              MVT::v8i16, Custom);
> >     setOperationAction(ISD::SDIV,              MVT::v4i32, Custom);
> >   }
> > @@ -1186,14 +1179,6 @@ X86TargetLowering::X86TargetLowering(X86
> > 
> >       setOperationAction(ISD::VSELECT,         MVT::v32i8, Legal);
> > 
> > -      setOperationAction(ISD::SRL,             MVT::v4i64, Legal);
> > -      setOperationAction(ISD::SRL,             MVT::v8i32, Legal);
> > -
> > -      setOperationAction(ISD::SHL,             MVT::v4i64, Legal);
> > -      setOperationAction(ISD::SHL,             MVT::v8i32, Legal);
> > -
> > -      setOperationAction(ISD::SRA,             MVT::v8i32, Legal);
> > -
> >       setOperationAction(ISD::SDIV,            MVT::v8i32, Custom);
> >     } else {
> >       setOperationAction(ISD::ADD,             MVT::v4i64, Custom);
> > @@ -1210,15 +1195,17 @@ X86TargetLowering::X86TargetLowering(X86
> >       setOperationAction(ISD::MUL,             MVT::v8i32, Custom);
> >       setOperationAction(ISD::MUL,             MVT::v16i16, Custom);
> >       // Don't lower v32i8 because there is no 128-bit byte mul
> > +    }
> > 
> > -      setOperationAction(ISD::SRL,             MVT::v4i64, Custom);
> > -      setOperationAction(ISD::SRL,             MVT::v8i32, Custom);
> > +    // In the customized shift lowering, the legal cases in AVX2
> > will be
> > +    // recognized.
> > +    setOperationAction(ISD::SRL,               MVT::v4i64, Custom);
> > +    setOperationAction(ISD::SRL,               MVT::v8i32, Custom);
> > 
> > -      setOperationAction(ISD::SHL,             MVT::v4i64, Custom);
> > -      setOperationAction(ISD::SHL,             MVT::v8i32, Custom);
> > +    setOperationAction(ISD::SHL,               MVT::v4i64, Custom);
> > +    setOperationAction(ISD::SHL,               MVT::v8i32, Custom);
> > 
> > -      setOperationAction(ISD::SRA,             MVT::v8i32, Custom);
> > -    }
> > +    setOperationAction(ISD::SRA,               MVT::v8i32, Custom);
> > 
> >     // Custom lower several nodes for 256-bit types.
> >     for (int i = MVT::FIRST_VECTOR_VALUETYPE;
> > @@ -11626,6 +11613,20 @@ SDValue X86TargetLowering::LowerShift(SD
> >   if (V.getNode())
> >     return V;
> > 
> > +  // AVX2 has VPSLLV/VPSRAV/VPSRLV.
> > +  if (Subtarget->hasInt256()) {
> > +    if (Op.getOpcode() == ISD::SRL &&
> > +        (VT == MVT::v2i64 || VT == MVT::v4i32 ||
> > +         VT == MVT::v4i64 || VT == MVT::v8i32))
> > +      return Op;
> > +    if (Op.getOpcode() == ISD::SHL &&
> > +        (VT == MVT::v2i64 || VT == MVT::v4i32 ||
> > +         VT == MVT::v4i64 || VT == MVT::v8i32))
> > +      return Op;
> > +    if (Op.getOpcode() == ISD::SRA && (VT == MVT::v4i32 || VT ==
> > MVT::v8i32))
> > +      return Op;
> > +  }
> > +
> >   // Lower SHL with variable shift amount.
> >   if (VT == MVT::v4i32 && Op->getOpcode() == ISD::SHL) {
> >     Op = DAG.getNode(ISD::SHL, dl, VT, Amt, DAG.getConstant(23,
> > VT));
> > 
> > 
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