[llvm] Reland: Port Swift's merge function pass to llvm: merging functions that differ in constants (PR #71584)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,29 @@
+//===- MergeFunctionsIgnoringConst.h - Merge Functions ---------*- 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 file defines helpers used in the MergeFunctionsIgnoringConst.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_UTILS_MERGEFUNCTIONSIGNORINGCONST_H
+#define LLVM_TRANSFORMS_UTILS_MERGEFUNCTIONSIGNORINGCONST_H
+
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Operator.h"
+
+using namespace llvm;
+
+bool isEligibleInstrunctionForConstantSharing(const Instruction *I);
+
+bool isEligibleOperandForConstantSharing(const Instruction *I, unsigned OpIdx);
+
+bool isEligibleFunction(Function *F);
+
+Value *createCast(IRBuilder<> &Builder, Value *V, Type *DestTy);
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nikic wrote:

It is necessary to export all of these functions? createCast() sounds like an implementation detail.

https://github.com/llvm/llvm-project/pull/71584