llvm-project/llvm/lib/VMCore/iBranch.cpp

59 lines
2.0 KiB
C++

//===-- iBranch.cpp - Implement the Branch instruction --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the 'br' instruction, which can represent either a
// conditional or unconditional branch.
//
//===----------------------------------------------------------------------===//
#include "llvm/iTerminators.h"
#include "llvm/BasicBlock.h"
#include "llvm/Type.h"
using namespace llvm;
// Out-of-line ReturnInst method, put here so the C++ compiler can choose to
// emit the vtable for the class in this translation unit.
void ReturnInst::setSuccessor(unsigned idx, BasicBlock *NewSucc) {
assert(0 && "ReturnInst has no successors!");
}
// Likewise for UnwindInst
void UnwindInst::setSuccessor(unsigned idx, BasicBlock *NewSucc) {
assert(0 && "UnwindInst has no successors!");
}
void BranchInst::init(BasicBlock *IfTrue)
{
assert(IfTrue != 0 && "Branch destination may not be null!");
Operands.reserve(1);
Operands.push_back(Use(IfTrue, this));
}
void BranchInst::init(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond)
{
assert(IfTrue && IfFalse && Cond &&
"Branch destinations and condition may not be null!");
assert(Cond && Cond->getType() == Type::BoolTy &&
"May only branch on boolean predicates!");
Operands.reserve(3);
Operands.push_back(Use(IfTrue, this));
Operands.push_back(Use(IfFalse, this));
Operands.push_back(Use(Cond, this));
}
BranchInst::BranchInst(const BranchInst &BI) : TerminatorInst(Instruction::Br) {
Operands.reserve(BI.Operands.size());
Operands.push_back(Use(BI.Operands[0], this));
if (BI.Operands.size() != 1) {
assert(BI.Operands.size() == 3 && "BR can have 1 or 3 operands!");
Operands.push_back(Use(BI.Operands[1], this));
Operands.push_back(Use(BI.Operands[2], this));
}
}