[llvm] [VPlan] Extract reverse mask from reverse accesses (PR #155579)

[Luke Lau via llvm-commits]

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@@ -3112,11 +3112,12 @@ static VPRecipeBase *optimizeMaskToEVL(VPValue *HeaderMask,
       match(ReversedVal,
             m_MaskedLoad(m_VPValue(EndPtr),
                          m_Reverse(m_RemoveMask(HeaderMask, Mask)))) &&
-      match(EndPtr, m_VecEndPtr(m_VPValue(Addr), m_Specific(&Plan->getVF())))) {
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lukel97 wrote:

It doesn't look like Addr was used beforehand. How come this causes an unspecified evaluation order?

https://github.com/llvm/llvm-project/pull/155579