[llvm] [AMDGPU][True16][CodeGen] true16 codegen pattern for fma (PR #127240)

[Matt Arsenault via llvm-commits]

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@@ -4076,11 +4094,14 @@ MachineInstr *SIInstrInfo::convertToThreeAddress(MachineInstr &MI,
         return MIB;
       }
     }
-    unsigned NewOpc =
-        IsFMA ? (IsF16 ? (ST.hasTrue16BitInsts() ? AMDGPU::V_FMAMK_F16_fake16
-                                                 : AMDGPU::V_FMAMK_F16)
-                       : AMDGPU::V_FMAMK_F32)
-              : (IsF16 ? AMDGPU::V_MADMK_F16 : AMDGPU::V_MADMK_F32);
+    unsigned NewOpc = IsFMA
+                          ? (IsF16 ? (ST.hasTrue16BitInsts()
+                                          ? ST.useRealTrue16Insts()
+                                                ? AMDGPU::V_FMAMK_F16_t16
+                                                : AMDGPU::V_FMAMK_F16_fake16
+                                          : AMDGPU::V_FMAMK_F16)
+                                   : AMDGPU::V_FMAMK_F32)
+                          : (IsF16 ? AMDGPU::V_MADMK_F16 : AMDGPU::V_MADMK_F32);
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arsenm wrote:

Factor both of these nasty nested ternary operators into a helper function 

https://github.com/llvm/llvm-project/pull/127240