[llvm] [GlobalISel][AArch64] Add G_FPTOSI_SAT/G_FPTOUI_SAT (PR #96297)

[Matt Arsenault via llvm-commits]

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@@ -2130,6 +2130,12 @@ bool AArch64InstructionSelector::preISelLower(MachineInstr &I) {
     }
     return false;
   }
+  case TargetOpcode::G_FPTOSI_SAT:
+    I.setDesc(TII.get(TargetOpcode::G_FPTOSI));
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arsenm wrote:

It would be necessary if the floating point type required legalization. We probably need an equivalent operand here, and then some TableGen magic to get the patterns to work 

https://github.com/llvm/llvm-project/pull/96297