[clang] [lld] [flang] [llvm] [AMDGPU] Introduce GFX9/10.1/10.3/11 Generic Targets (PR #76955)

[Konstantin Zhuravlyov via cfe-commits]

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@@ -520,6 +520,106 @@ Every processor supports every OS ABI (see :ref:`amdgpu-os`) with the following
 
      =========== =============== ============ ===== ================= =============== =============== ======================
 
+Generic processors also exist. They group multiple processors into one,
+allowing to build code once and run it on multiple targets at the cost
+of less features being available.
+
+Generic processors are only available on Code Object V6 and up.
+
+  .. table:: AMDGPU Generic Processors
+     :name: amdgpu-generic-processor-table
+
+     ==================== ============== ================= =================================
+     Processor             Target        Supported         Target
+                           Triple        Processors        Features
+                           Architecture                    Restrictions
+
+
+
+
+
+
+
+
+     ==================== ============== ================= =================================
+     ``gfx9-generic``     ``amdgcn``     - ``gfx900``      - ``v_mad_mix`` instructions
+                                         - ``gfx902``        are not available on
+                                         - ``gfx904``        ``gfx900``, ``gfx902``,
+                                         - ``gfx906``        ``gfx909``, ``gfx90c``
+                                         - ``gfx909``      - ``v_fma_mix`` instructions
+                                         - ``gfx90c``        are not available on ``gfx904``
+                                                           - sramecc is not available on
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kzhuravl wrote:

Discussed with @Pierre-vh offline. @Pierre-vh will add a test making sure no d16 instructions produced for generic-gfx9.

https://github.com/llvm/llvm-project/pull/76955