[RISCV] Add cost model for vector.reverse mask operation

[Jimerlife]

Summary

For vector.reverse mask operation need additional extend and truncate. So, I try to adjust this cost model.

[Jimerlife]

gentle ping

[craig.topper]

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp

203

Isn't extend 2 instructions, vmv+vmerge?

[Jimerlife]

address comment

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp

203

Yes, you are right. I forget to add vmv. Thank you.

[Jimerlife]

ping...

[craig.topper]

LGTM

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp

case TTI::SK_Reverse:
       // Example sequence:
       //   csrr a0, vlenb
       //   srli a0, a0, 3
       //   addi a0, a0, -1
       //   vsetvli a1, zero, e8, mf8, ta, mu (ignored)
       //   vid.v v9
       //   vrsub.vx v10, v9, a0
       //   vrgather.vv v9, v8, v10
+      if (Tp->getElementType()->isIntegerTy(1))
+        // Mask operation additionally required extend and truncate
+        return LT.first * 8;
       return LT.first * 6;
     }
   }
 
   return BaseT::getShuffleCost(Kind, Tp, Mask, Index, SubTp);
 }
 
 InstructionCost

llvm/test/Analysis/CostModel/RISCV/rvv-shuffle.ll

 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv2i16 = call <vscale x 2 x i16> @llvm.experimental.vector.reverse.nxv2i16(<vscale x 2 x i16> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv4i16 = call <vscale x 4 x i16> @llvm.experimental.vector.reverse.nxv4i16(<vscale x 4 x i16> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv8i16 = call <vscale x 8 x i16> @llvm.experimental.vector.reverse.nxv8i16(<vscale x 8 x i16> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv16i16 = call <vscale x 16 x i16> @llvm.experimental.vector.reverse.nxv16i16(<vscale x 16 x i16> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv4i32 = call <vscale x 4 x i32> @llvm.experimental.vector.reverse.nxv4i32(<vscale x 4 x i32> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv8i32 = call <vscale x 8 x i32> @llvm.experimental.vector.reverse.nxv8i32(<vscale x 8 x i32> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv2i64 = call <vscale x 2 x i64> @llvm.experimental.vector.reverse.nxv2i64(<vscale x 2 x i64> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv4i64 = call <vscale x 4 x i64> @llvm.experimental.vector.reverse.nxv4i64(<vscale x 4 x i64> undef)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv16i1 = call <vscale x 16 x i1> @llvm.experimental.vector.reverse.nxv16i1(<vscale x 16 x i1> undef)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv8i1 = call <vscale x 8 x i1> @llvm.experimental.vector.reverse.nxv8i1(<vscale x 8 x i1> undef)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv4i1 = call <vscale x 4 x i1> @llvm.experimental.vector.reverse.nxv4i1(<vscale x 4 x i1> undef)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %reverse_nxv2i1 = call <vscale x 2 x i1> @llvm.experimental.vector.reverse.nxv2i1(<vscale x 2 x i1> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %reverse_nxv16i1 = call <vscale x 16 x i1> @llvm.experimental.vector.reverse.nxv16i1(<vscale x 16 x i1> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %reverse_nxv8i1 = call <vscale x 8 x i1> @llvm.experimental.vector.reverse.nxv8i1(<vscale x 8 x i1> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %reverse_nxv4i1 = call <vscale x 4 x i1> @llvm.experimental.vector.reverse.nxv4i1(<vscale x 4 x i1> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %reverse_nxv2i1 = call <vscale x 2 x i1> @llvm.experimental.vector.reverse.nxv2i1(<vscale x 2 x i1> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
   %reverse_nxv16i8 = call <vscale x 16 x i8> @llvm.experimental.vector.reverse.nxv16i8(<vscale x 16 x i8> undef)
   %reverse_nxv32i8 = call <vscale x 32 x i8> @llvm.experimental.vector.reverse.nxv32i8(<vscale x 32 x i8> undef)
   %reverse_nxv2i16 = call <vscale x 2 x i16> @llvm.experimental.vector.reverse.nxv2i16(<vscale x 2 x i16> undef)
   %reverse_nxv4i16 = call <vscale x 4 x i16> @llvm.experimental.vector.reverse.nxv4i16(<vscale x 4 x i16> undef)
   %reverse_nxv8i16 = call <vscale x 8 x i16> @llvm.experimental.vector.reverse.nxv8i16(<vscale x 8 x i16> undef)
   %reverse_nxv16i16 = call <vscale x 16 x i16> @llvm.experimental.vector.reverse.nxv16i16(<vscale x 16 x i16> undef)