[llvm] [X86][PartialReduction] Lower zext-byte add reductions to vpsadbw (PR #201076)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,206 @@
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2 | FileCheck %s --check-prefix=NO-PSADBW
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RKSimon wrote:

single RUN - just use CHECK (default) instead of NO-PSADBW

https://github.com/llvm/llvm-project/pull/201076