[PATCH] D101836: [LoopVectorize] Enable strict reductions when allowReordering() returns false

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


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Comment at: llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h:140
 
   bool allowReordering() const {
     // When enabling loop hints are provided we allow the vectorizer to change
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I'd suggest moving the implementation of `allowReordering` to `LoopVectorizationLegality.cpp`, so that you don't need to add the extern+include above.


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Comment at: llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp:874-875
+
+  if (!EnableStrictReductions)
+    return false;
+
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nit: can you fold this into the condition below:

  if (!EnableStrictReductions || any_of(...))
    return false;


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Comment at: llvm/test/Transforms/LoopVectorize/AArch64/strict-fadd.ll:3
+; RUN: opt < %s -loop-vectorize -mtriple aarch64-unknown-linux-gnu -enable-strict-reductions=false -hints-allow-reordering=true  -S 2>%t | FileCheck %s --check-prefix=CHECK-UNORDERED
+; RUN: opt < %s -loop-vectorize -mtriple aarch64-unknown-linux-gnu -enable-strict-reductions=true  -hints-allow-reordering=false -S 2>%t | FileCheck %s --check-prefix=CHECK-ORDERED
 
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Can you also add a RUN line for `-enable-strict-reductions=true  -hints-allow-reordering=true` (which I think can reuse prefix CHECK-UNORDERED)


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