[llvm] Allow empty range attribute and add assert for full range (PR #100601)

[Nikita Popov via llvm-commits]

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@@ -286,6 +286,12 @@ Attribute Attribute::getWithNoFPClass(LLVMContext &Context,
   return get(Context, NoFPClass, ClassMask);
 }
 
+Attribute Attribute::getWithRange(LLVMContext &Context,
+                                  const ConstantRange &CR) {
+  assert(!CR.isFullSet() && "Range must not be full!");
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nikic wrote:

I think it would be okay to just add this directly into the generic ctor, rather than specific to `range`. I would expect that other range-based attributes added in the future will not allow full ranges either. (If they do, we can separate it out at the time.)

https://github.com/llvm/llvm-project/pull/100601