[llvm] [AMDGPU][MC][True16] Support VOP2 instructions with true16 format (PR #115233)

[Joe Nash via llvm-commits]

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@@ -467,6 +479,42 @@ class VOP_MAC <ValueType vt0, ValueType vt1=vt0> : VOPProfile <[vt0, vt1, vt1, v
 }
 
 def VOP_MAC_F16 : VOP_MAC <f16>;
+def VOP_MAC_F16_t16 : VOP_MAC <f16> {
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Sisyph wrote:

I don't see a way to reduce it much. These lets are pretty much standard for a true16 instruction. But we have the true16 lets, and all the VOP_MAC lets to support. We could inherit from VOPProfile_TRUE16 instead of VOP_MAC, but then we'd have all the same lets here as in VOP_MAC.  One upside is when the default is switched to true16, we can delete 6 lines related to VOP3DPP.

https://github.com/llvm/llvm-project/pull/115233