[llvm-branch-commits] [llvm] [LV][REVEC] Initial support for re-vectorisation (PR #208213)

[Andrei Elovikov via llvm-branch-commits]

=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>,
=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>,
=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>,
=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>,
=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>,
=?utf-8?q?Gaëtan?= Bossu <gaetan.bossu at arm.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/208213 at github.com>


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@@ -423,9 +432,13 @@ FixedScalableVFPair VFSelectionContext::computeFeasibleMaxVF(
 
     if (ElementCount::isKnownLE(UserVF, MaxSafeUserVF)) {
       // If `VF=vscale x N` is safe, then so is `VF=N`
-      if (UserVF.isScalable())
-        return FixedScalableVFPair(
-            ElementCount::getFixed(UserVF.getKnownMinValue()), UserVF);
+      // (unless it's wider than MaxSafeFixedVF).
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eas wrote:

Can you please explain this more?

https://github.com/llvm/llvm-project/pull/208213