[llvm] [CVP][LVI] Add support for vectors (PR #97428)

[via llvm-commits]

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@@ -844,6 +862,9 @@ static ConstantRange toConstantRange(const ValueLatticeElement &Val,
   unsigned BW = Ty->getScalarSizeInBits();
   if (Val.isUnknown())
     return ConstantRange::getEmpty(BW);
+  if (Val.isConstant())
+    if (auto *VTy = dyn_cast<FixedVectorType>(Ty))
+      return getConstantRangeFromVector(Val.getConstant(), VTy);
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goldsteinn wrote:

What about just using `computeConstantRange` to do it?
AFAICT the only case they handle differently is `poison` elements.

https://github.com/llvm/llvm-project/pull/97428