[llvm] [Hexagon][DAG][FREEZE] Fix bug 117337 (PR #119042)

[Brian Cain via llvm-commits]

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@@ -363,6 +363,8 @@ class HexagonTargetLowering : public TargetLowering {
     return AtomicExpansionKind::LLSC;
   }
 
+  bool softPromoteHalfType() const override { return true; }
+
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androm3da wrote:

`CodeGen/Hexagon/isel-buildvector-v2f16.ll` fails with this change.

https://github.com/llvm/llvm-project/pull/119042