[llvm] [AMDGPU] Enable constant offset promotion to immediate FLAT (PR #93884)

[Matt Arsenault via llvm-commits]

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@@ -212,3 +212,51 @@ body:             |
     %13:vreg_64 = REG_SEQUENCE %9, %subreg.sub0, %11, %subreg.sub1
     GLOBAL_STORE_DWORD %13, %0.sub1, 0, 0, implicit $exec
 ...
+---
+
+# GFX9-LABEL: name: diffoporder_add_flat_load
+# GFX9: FLAT_LOAD_DWORD %{{[0-9]+}}, 1000, 0,
+# GFX9: FLAT_LOAD_DWORD %{{[0-9]+}}, 0, 0,
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arsenm wrote:

Needs a gfx8 run line to make sure the offset isn't introduced 

https://github.com/llvm/llvm-project/pull/93884