[llvm] [AMDGPU] Add type-generic llvm.amdgcn.readfirstlane2 intrinsic (PR #87334)

[Matt Arsenault via llvm-commits]

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@@ -1,71 +1,176 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
 ; RUN: llc -mtriple=amdgcn--amdhsa -mcpu=fiji -verify-machineinstrs < %s | FileCheck -enable-var-scope %s
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arsenm wrote:

global-isel checks 

https://github.com/llvm/llvm-project/pull/87334