[llvm] [InlineCost] Cache collectEphemeralValues() to save compile time (PR #130210)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,59 @@
+//===- llvm/Analysis/EphemeralValuesCache.h ---------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass caches ephemeral values, i.e., values that are only used by
+// @llvm.assume intrinsics, for cheap access after the initial collection.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_EPHEMERALVALUESCACHE_H
+#define LLVM_ANALYSIS_EPHEMERALVALUESCACHE_H
+
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/Analysis/AssumptionCache.h"
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nikic wrote:

I think you could forward-declare AssumptionCache?

https://github.com/llvm/llvm-project/pull/130210