Assumptions.h

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//===--- Assumptions.h - Assumption handling and organization ---*- 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
//
//===----------------------------------------------------------------------===//
//
// String assumptions that are known to optimization passes should be placed in
// the KnownAssumptionStrings set. This can be done in various ways, i.a.,
// via a static KnownAssumptionString object.
//
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_IR_ASSUMPTIONS_H
#define LLVM_IR_ASSUMPTIONS_H
 
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Support/Compiler.h"
 
namespace llvm {
 
class Function;
class CallBase;
 
/// The key we use for assumption attributes.
constexpr StringRef AssumptionAttrKey = "llvm.assume";
 
/// A set of known assumption strings that are accepted without warning and
/// which can be recommended as typo correction.
LLVM_ABI extern StringSet<> &getKnownAssumptionStrings();
 
/// Helper that allows to insert a new assumption string in the known assumption
/// set by creating a (static) object.
struct KnownAssumptionString {
  KnownAssumptionString(const char *AssumptionStr)
      : AssumptionStr(AssumptionStr) {
    getKnownAssumptionStrings().insert(AssumptionStr);
  }
  KnownAssumptionString(StringRef AssumptionStr)
      : AssumptionStr(AssumptionStr) {
    getKnownAssumptionStrings().insert(AssumptionStr);
  }
  operator StringRef() const { return AssumptionStr; }
 
private:
  StringRef AssumptionStr;
};
 
/// Return true if \p F has the assumption \p AssumptionStr attached.
LLVM_ABI bool hasAssumption(const Function &F,
                            const KnownAssumptionString &AssumptionStr);
 
/// Return true if \p CB or the callee has the assumption \p AssumptionStr
/// attached.
LLVM_ABI bool hasAssumption(const CallBase &CB,
                            const KnownAssumptionString &AssumptionStr);
 
/// Return the set of all assumptions for the function \p F.
LLVM_ABI DenseSet<StringRef> getAssumptions(const Function &F);
 
/// Return the set of all assumptions for the call \p CB.
LLVM_ABI DenseSet<StringRef> getAssumptions(const CallBase &CB);
 
/// Appends the set of assumptions \p Assumptions to \F.
LLVM_ABI bool addAssumptions(Function &F,
                             const DenseSet<StringRef> &Assumptions);
 
/// Appends the set of assumptions \p Assumptions to \CB.
LLVM_ABI bool addAssumptions(CallBase &CB,
                             const DenseSet<StringRef> &Assumptions);
 
} // namespace llvm
 
#endif