[llvm] [RISC-V][GlobaISel] Legalize G_ATOMIC_CMPXCHG and G_ATOMIC_CMPXCHG_WITH_SUCCESS (PR #157634)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,5910 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -global-isel -mtriple=riscv32 -verify-machineinstrs < %s \
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arsenm wrote:

Don't need all the -verify-machineinstrs 

https://github.com/llvm/llvm-project/pull/157634