[clang] [HLSL] Shore up floating point conversions (PR #90222)

[Farzon Lotfi via cfe-commits]

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@@ -4393,6 +4401,24 @@ getFixedEnumPromtion(Sema &S, const StandardConversionSequence &SCS) {
   return FixedEnumPromotion::ToPromotedUnderlyingType;
 }
 
+static ImplicitConversionSequence::CompareKind
+HLSLCompareFloatingRank(QualType LHS, QualType RHS) {
+  assert(LHS->isVectorType() == RHS->isVectorType() &&
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farzonl wrote:

Is this true? are there no vector splat cases we need to consider where we would promote a scalar to a vector?

https://github.com/llvm/llvm-project/pull/90222