[llvm] [IR] Add new Range attribute using new ConstantRange Attribute type (PR #83171)

[Nikita Popov via llvm-commits]

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@@ -1634,6 +1634,22 @@ Currently, only the following parameter attributes are defined:
 
     This attribute cannot be applied to return values.
 
+``range(<ty> <a>, <b>)``
+    This attribute expresses the possible range the parameter is in. The value of 
+    the parameter is in the specified range or is poison.
+    The arguments passed to ``range`` has the following properties:
+
+    -  The type must match the scalar type of the parameter.
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nikic wrote:

It does apply to all vector elements:

> For vector-typed parameters, the range is applied element-wise.

https://github.com/llvm/llvm-project/pull/83171