[llvm] [VPlan] Recursively match operands of interleave group (PR #164839)

[Ramkumar Ramachandra via llvm-commits]

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@@ -0,0 +1,182 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
+; RUN: opt %s -passes=loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -enable-interleaved-mem-accesses -S | FileCheck %s
+
+define void @pr128062(ptr %dst.start, i8 %a, i16 %b) {
+; CHECK-LABEL: define void @pr128062(
+; CHECK-SAME: ptr [[DST_START:%.*]], i8 [[A:%.*]], i16 [[B:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i16> poison, i16 [[B]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i16> [[BROADCAST_SPLATINSERT]], <4 x i16> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <4 x i8> poison, i8 [[A]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT1]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = mul i64 [[INDEX]], 4
+; CHECK-NEXT:    [[NEXT_GEP:%.*]] = getelementptr i8, ptr [[DST_START]], i64 [[OFFSET_IDX]]
+; CHECK-NEXT:    [[WIDE_VEC:%.*]] = load <16 x i8>, ptr [[NEXT_GEP]], align 1
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artagnon wrote:

Thanks for spotting! I think the regression cases also do this: investigating.

https://github.com/llvm/llvm-project/pull/164839