//===-- OverflowInstAnalysis.h - Utils to fold overflow insts ----*- 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 holds routines to help analyse overflow instructions
 
// and fold them into constants or other overflow instructions
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_ANALYSIS_OVERFLOWINSTANALYSIS_H
 
#define LLVM_ANALYSIS_OVERFLOWINSTANALYSIS_H
 
 
 
namespace llvm {
 
class Use;
 
class Value;
 
 
 
/// Match one of the patterns up to the select/logic op:
 
///   %Op0 = icmp ne i4 %X, 0
 
///   %Agg = call { i4, i1 } @llvm.[us]mul.with.overflow.i4(i4 %X, i4 %Y)
 
///   %Op1 = extractvalue { i4, i1 } %Agg, 1
 
///   %ret = select i1 %Op0, i1 %Op1, i1 false / %ret = and i1 %Op0, %Op1
 
///
 
///   %Op0 = icmp eq i4 %X, 0
 
///   %Agg = call { i4, i1 } @llvm.[us]mul.with.overflow.i4(i4 %X, i4 %Y)
 
///   %NotOp1 = extractvalue { i4, i1 } %Agg, 1
 
///   %Op1 = xor i1 %NotOp1, true
 
///   %ret = select i1 %Op0, i1 true, i1 %Op1 / %ret = or i1 %Op0, %Op1
 
///
 
/// Callers are expected to align that with the operands of the select/logic.
 
/// IsAnd is set to true if the Op0 and Op1 are used as the first pattern.
 
/// If Op0 and Op1 match one of the patterns above, return true and fill Y's
 
/// use.
 
 
 
bool isCheckForZeroAndMulWithOverflow(Value *Op0, Value *Op1, bool IsAnd,
 
                                      Use *&Y);
 
bool isCheckForZeroAndMulWithOverflow(Value *Op0, Value *Op1, bool IsAnd);
 
} // end namespace llvm
 
 
 
#endif