[PATCH] D101076: [SVE][LoopVectorize] Add support for scalable vectorization of first-order recurrences

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


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Comment at: llvm/lib/IR/IRBuilder.cpp:1047
+  if ((-Imm > NumElts) || (Imm >= NumElts)) {
+    return UndefValue::get(V1->getType());
+  }
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Is this case actually used? Do we need to support this case, or can we assert that `Imm` always is valid? (might also be good to mention in the comment what values of `Imm` are supported).


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Comment at: llvm/test/Transforms/LoopVectorize/AArch64/first-order-recurrence.ll:1
+; RUN: opt -loop-vectorize -mtriple aarch64-unknown-linux-gnu -mattr=+sve -S < %s | FileCheck %s
+
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Is there anything `AArch64` specific about the test? The VFs are all forced, so no cost-modeling should be needed, could this just use `-force-target-supports-scalable-vectors`?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D101076/new/

https://reviews.llvm.org/D101076