[llvm] [VPlan] Materialize vector trip count using VPInstructions. (PR #151925)

[Luke Lau via llvm-commits]

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@@ -18,37 +18,14 @@ define void @masked_strided_factor2(ptr noalias nocapture readonly %p, ptr noali
 ; SCALAR_EPILOGUE-NEXT:    [[TMP2:%.*]] = shl nuw i32 [[TMP1]], 4
 ; SCALAR_EPILOGUE-NEXT:    [[N_MOD_VF:%.*]] = urem i32 1024, [[TMP2]]
 ; SCALAR_EPILOGUE-NEXT:    [[N_VEC:%.*]] = sub nuw nsw i32 1024, [[N_MOD_VF]]
-; SCALAR_EPILOGUE-NEXT:    [[TMP3:%.*]] = call i32 @llvm.vscale.i32()
-; SCALAR_EPILOGUE-NEXT:    [[TMP4:%.*]] = shl nuw i32 [[TMP3]], 4
 ; SCALAR_EPILOGUE-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <vscale x 16 x i32> poison, i32 [[CONV]], i64 0
 ; SCALAR_EPILOGUE-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <vscale x 16 x i32> [[BROADCAST_SPLATINSERT]], <vscale x 16 x i32> poison, <vscale x 16 x i32> zeroinitializer
-; SCALAR_EPILOGUE-NEXT:    [[TMP5:%.*]] = call <vscale x 16 x i32> @llvm.stepvector.nxv16i32()
-; SCALAR_EPILOGUE-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <vscale x 16 x i32> poison, i32 [[TMP4]], i64 0
+; SCALAR_EPILOGUE-NEXT:    [[TMP3:%.*]] = call <vscale x 16 x i32> @llvm.stepvector.nxv16i32()
+; SCALAR_EPILOGUE-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <vscale x 16 x i32> poison, i32 [[TMP2]], i64 0
 ; SCALAR_EPILOGUE-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <vscale x 16 x i32> [[BROADCAST_SPLATINSERT1]], <vscale x 16 x i32> poison, <vscale x 16 x i32> zeroinitializer
 ; SCALAR_EPILOGUE-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; SCALAR_EPILOGUE:       vector.body:
 ; SCALAR_EPILOGUE-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; SCALAR_EPILOGUE-NEXT:    [[VEC_IND:%.*]] = phi <vscale x 16 x i32> [ [[TMP5]], [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ]
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lukel97 wrote:

I think these lines are getting accidentally stripped. Do we need to drop/fix the `--filter-out-after=^scalar.ph` arg?

https://github.com/llvm/llvm-project/pull/151925