[llvm] AMDGPU: share LDS budget logic and add experimental LDS buffering pass (PR #166388)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,28 @@
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx950 -passes=amdgpu-lds-buffering -S %s | FileCheck %s
+
+; Check LDS global creation
+; CHECK: @ldsbuf_test.ldsbuf = internal unnamed_addr addrspace(3) global
+
+; CHECK-LABEL: @ldsbuf_test(
+; Ensure the original direct global load is gone before the first memcpy-in
+; CHECK-NOT: load <4 x i32>, ptr addrspace(1) %p
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arsenm wrote:

-NOT is fragile. Can you just generate checks? 

https://github.com/llvm/llvm-project/pull/166388