[llvm] [AArch64][GlobalISel] Add better basic legalization for llround. (PR #168427)

[via llvm-commits]

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@@ -449,10 +449,12 @@ AArch64LegalizerInfo::AArch64LegalizerInfo(const AArch64Subtarget &ST)
       .minScalar(0, s32)
       .libcallFor({{s32, s32}, {s64, s32}, {s128, s32}});
 
-  // TODO: Libcall support for s128.
-  // TODO: s16 should be legal with full FP16 support.
   getActionDefinitionsBuilder({G_LROUND, G_LLROUND})
-      .legalFor({{s64, s32}, {s64, s64}});
+      .legalFor({{s64, s32}, {s64, s64}})
+      .legalFor(HasFP16, {{s64, s16}})
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Lukacma wrote:

Is there a specific reason why {s32, s16} and {s32, s64} is not legal for LROUND here? If I understand correctly, that's how it is for SelectionDAG

https://github.com/llvm/llvm-project/pull/168427