[PATCH] D102675: [SLP] Fix "gathering" of vector values

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:3693-3695
+    // No cost for "gathering" already vector value
+    if (isa<FixedVectorType>(VL[0]->getType()))
+      return 0;
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Not sure we should return `0` here, maybe better to return some max cost, like `INT_MAX`?


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Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:4597-4599
+  // "Gathering" of vector values is already done
+  if (isa<FixedVectorType>(Val0->getType()))
+    return Val0;
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Is this correct? Need to return the last insertelement instruction in the sequence


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/insert-element-build-vector-inseltpoison.ll:45-80
-; CHECK-LABEL: @simple_select_eph(
-; CHECK-NEXT:    [[C0:%.*]] = extractelement <4 x i32> [[C:%.*]], i32 0
-; CHECK-NEXT:    [[C1:%.*]] = extractelement <4 x i32> [[C]], i32 1
-; CHECK-NEXT:    [[C2:%.*]] = extractelement <4 x i32> [[C]], i32 2
-; CHECK-NEXT:    [[C3:%.*]] = extractelement <4 x i32> [[C]], i32 3
-; CHECK-NEXT:    [[A0:%.*]] = extractelement <4 x float> [[A:%.*]], i32 0
-; CHECK-NEXT:    [[A1:%.*]] = extractelement <4 x float> [[A]], i32 1
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Why the check lines are removed?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102675/new/

https://reviews.llvm.org/D102675