[llvm] [AMDGPU] Add inreg support for SGPR arguments (PR #67182)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,359 @@
+; RUN: llc -march=amdgcn -mcpu=gfx900 -mattr=-flat-for-global -verify-machineinstrs < %s | FileCheck -enable-var-scope -check-prefixes=CIGFX89,GFX89 %s
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arsenm wrote:

Remove -mattr=-flat-for-global, the only real reason to use that was trying to share manually written tests ages ago 

https://github.com/llvm/llvm-project/pull/67182