[llvm] [AMDGPU] Support block load/store for CSR (PR #130013)

[Matt Arsenault via llvm-commits]

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@@ -384,6 +384,20 @@ class PrologEpilogSGPRSaveRestoreInfo {
   SGPRSaveKind getKind() const { return Kind; }
 };
 
+constexpr unsigned FirstVGPRBlock = AMDGPU::
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arsenm wrote:

Can you just do VGPR_1024RegClass.front() and .back()?

https://github.com/llvm/llvm-project/pull/130013