MachineFloatingPointPredicateUtils.h

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//===-- MachineFloatingPointModeUtils.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
//
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_CODEGEN_MACHINEFLOATINGPOINTPREDICATEUTILS_H
#define LLVM_CODEGEN_MACHINEFLOATINGPOINTPREDICATEUTILS_H
 
#include "llvm/CodeGen/MachineSSAContext.h"
#include "llvm/IR/GenericFloatingPointPredicateUtils.h"
 
namespace llvm {
 
using MachineFloatingPointPredicateUtils =
    GenericFloatingPointPredicateUtils<MachineSSAContext>;
 
template <>
DenormalMode
MachineFloatingPointPredicateUtils::queryDenormalMode(const MachineFunction &MF,
                                                      Register Val);
 
template <>
bool MachineFloatingPointPredicateUtils::lookThroughFAbs(
    const MachineFunction &MF, Register LHS, Register &Src);
 
template <>
std::optional<APFloat> MachineFloatingPointPredicateUtils::matchConstantFloat(
    const MachineFunction &MF, Register Val);
 
/// Compute the possible floating-point classes that \p LHS could be based on
/// fcmp \Pred \p LHS, \p RHS.
///
/// \returns { TestedValue, ClassesIfTrue, ClassesIfFalse }
///
/// If the compare returns an exact class test, ClassesIfTrue ==
/// ~ClassesIfFalse
///
/// This is a less exact version of fcmpToClassTest (e.g. fcmpToClassTest will
/// only succeed for a test of x > 0 implies positive, but not x > 1).
///
/// If \p LookThroughSrc is true, consider the input value when computing the
/// mask. This may look through sign bit operations.
///
/// If \p LookThroughSrc is false, ignore the source value (i.e. the first
/// pair element will always be LHS.
///
inline std::tuple<Register, FPClassTest, FPClassTest>
fcmpImpliesClass(CmpInst::Predicate Pred, const MachineFunction &MF,
                 Register LHS, Register RHS, bool LookThroughSrc = true) {
  return MachineFloatingPointPredicateUtils::fcmpImpliesClass(
      Pred, MF, LHS, RHS, LookThroughSrc);
}
 
} // namespace llvm
 
#endif // LLVM_CODEGEN_MACHINEFLOATINGPOINTPREDICATEUTILS_H