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

[Luke Lau via llvm-commits]

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@@ -7167,10 +7162,14 @@ static bool planContainsAdditionalSimplifications(VPlan &Plan,
                 RepR->getUnderlyingInstr(), VF))
           return true;
       }
+
+      // vp.reverse is generated during EVL tail folding transformation.
+      if (match(&R, m_Intrinsic<Intrinsic::experimental_vp_reverse>()))
+        return true;
+
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lukel97 wrote:

Just tested with spec cpu 2017 + llvm-test-suite with rva23u64 ReleaseLTO with this commented out, and it also didn't hit any more assertions

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