[llvm] [DAGCombiner] Fold patterm for srl-shl-zext (PR #138290)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,40 @@
+; RUN: llc < %s -mtriple=nvptx64 | FileCheck %s
+
+define i64 @test1(i64 %x, i32 %y) {
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arsenm wrote:

Descriptive function name?

https://github.com/llvm/llvm-project/pull/138290