[llvm] Add the 'initializes' attribute langref and support (PR #84803)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,86 @@
+//===- ConstantRangeList.h - A list of constant ranges ----------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Represent a list of signed ConstantRange and do NOT support wrap around the
+// end of the numeric range. Ranges in the list are ordered and not overlapping.
+// Ranges should have the same bitwidth. Each range's lower should be less than
+// its upper.
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nikic wrote:

Something I noticed is that while ConstantRangeList maintains the "ordered and not overlapping" invariant through manipulations, it does not check that it initially holds. And indeed, LLParser will create such invalid ConstantRangeLists, which will later get rejected by the Verifier. Is this how it is *intended* to work out?

https://github.com/llvm/llvm-project/pull/84803