llvm-mirror/lib/VMCore/iSwitch.cpp
Chris Lattner e6b9b382e2 Initial revision
llvm-svn: 2
2001-06-06 20:29:01 +00:00

82 lines
2.2 KiB
C++

//===-- iSwitch.cpp - Implement the Switch instruction -----------*- C++ -*--=//
//
// This file implements the Switch instruction...
//
//===----------------------------------------------------------------------===//
#include "llvm/iTerminators.h"
#include "llvm/BasicBlock.h"
#ifndef NDEBUG
#include "llvm/Type.h"
#endif
SwitchInst::SwitchInst(Value *V, BasicBlock *DefV)
: TerminatorInst(Instruction::Switch),
DefaultDest(DefV, this), Val(V, this) {
assert(Val && DefV);
}
SwitchInst::SwitchInst(const SwitchInst &SI)
: TerminatorInst(Instruction::Switch), DefaultDest(SI.DefaultDest),
Val(SI.Val) {
for (dest_const_iterator I = SI.Destinations.begin(),
end = SI.Destinations.end(); I != end; ++I)
Destinations.push_back(dest_value(ConstPoolUse(I->first, this),
BasicBlockUse(I->second, this)));
}
void SwitchInst::dest_push_back(ConstPoolVal *OnVal, BasicBlock *Dest) {
Destinations.push_back(dest_value(ConstPoolUse(OnVal, this),
BasicBlockUse(Dest, this)));
}
void SwitchInst::dropAllReferences() {
Val = 0;
DefaultDest = 0;
Destinations.clear();
}
const BasicBlock *SwitchInst::getSuccessor(unsigned idx) const {
if (idx == 0) return DefaultDest;
if (idx > Destinations.size()) return 0;
return Destinations[idx-1].second;
}
unsigned SwitchInst::getNumOperands() const {
return 2+Destinations.size();
}
const Value *SwitchInst::getOperand(unsigned i) const {
if (i == 0) return Val;
else if (i == 1) return DefaultDest;
unsigned slot = (i-2) >> 1;
if (slot >= Destinations.size()) return 0;
if (i & 1) return Destinations[slot].second;
return Destinations[slot].first;
}
bool SwitchInst::setOperand(unsigned i, Value *V) {
if (i == 0) { Val = V; return true; }
else if (i == 1) {
assert(V->getType() == Type::LabelTy);
DefaultDest = (BasicBlock*)V;
return true;
}
unsigned slot = (i-2) >> 1;
if (slot >= Destinations.size()) return 0;
if (i & 1) {
assert(V->getType() == Type::LabelTy);
Destinations[slot].second = (BasicBlock*)V;
} else {
// TODO: assert constant
Destinations[slot].first = (ConstPoolVal*)V;
}
return true;
}