[llvm] [AMDGPU] Add `.amdgpu.info` section for per-function metadata (PR #192384)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,26 @@
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx908 -amdgpu-enable-object-linking < %s | FileCheck %s
+
+; Verify that .amdgpu_num_agpr IS emitted when AGPRs are used on a target
+; that supports them (gfx908 has a separate AGPR file).
+
+declare <4 x float> @llvm.amdgcn.mfma.f32.4x4x1f32(float, float, <4 x float>, i32, i32, i32)
+
+define void @func_with_agpr(float %a, float %b, ptr addrspace(1) %out) {
+  %result = call <4 x float> @llvm.amdgcn.mfma.f32.4x4x1f32(float %a, float %b, <4 x float> zeroinitializer, i32 0, i32 0, i32 0)
+  store <4 x float> %result, ptr addrspace(1) %out
+  ret void
+}
+
+define amdgpu_kernel void @kern(float %a, float %b, ptr addrspace(1) %out) {
+  call void @func_with_agpr(float %a, float %b, ptr addrspace(1) %out)
+  ret void
+}
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 1, !"amdgpu-link-time-lds", i32 1}
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arsenm wrote:

I don't see where this is defined or used 

https://github.com/llvm/llvm-project/pull/192384