// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
void AggregateCopyPropagation::SetBit(BitVector& vector, int bit) {
if(vector.BitCount() == (bit + 1)) {
vector.Resize(bit + 4);
}
vector.SetBit(bit);
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
void VariableAnalysis::ComputeBlockExposedAndKillSets(Block* block,
BitVector& exposedSet,
BitVector& killSet) {
// Scan all the instructions in the block and look for 'load' and 'store'.
for(auto instr = block->FirstInstruction(); instr;
instr = instr->NextInstruction()) {
if(auto storeInstr = instr->As<StoreInstr>()) {
// A variable can be killed only if it's stored into.
// Note that we don't care about the effects of function calls,
// because in that case the variable is marked as "address taken"
// and it isn't considered for SSA conversion anyway.
if(auto variableRef = storeInstr->DestinationOp()->As<VariableReference>()) {
auto localVar = variableRef->GetVariable();
if(localVar == nullptr) {
continue;
}
killSet.SetBit(localVar->Id());
}
}
else if(auto loadInstr = instr->As<LoadInstr>()) {
// The only way a variable can be "used" is through a 'load' instruction.
// All other kinds of uses will render the variable as being "address taken".
if(auto variableRef = loadInstr->SourceOp()->As<VariableReference>()) {
auto localVar = variableRef->GetVariable();
if(localVar == nullptr) {
continue;
}
// Mark the variable as 'exposed' only if it's not in the 'kill' set.
if(killSet.IsSet(localVar->Id()) == false) {
exposedSet.SetBit(localVar->Id());
}
}
}
}
}
void BitVector_Test::Test_bitVectorPopulationCount()
{
{
const u32 SIZE = 0;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
}
{
const u32 SIZE = 1;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
}
{
const u32 SIZE = 31;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
}
{
const u32 SIZE = 32;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
}
{
const u32 SIZE = 35;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
}
{
const u32 SIZE = 67;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(i);
assert(bits.PopulationCount() == i + 1);
}
// all combinations of start and len..
BitVector<SIZE> zbits;
for (u32 start = 0; start < SIZE; ++start)
{
for (u32 end = start; end < SIZE; ++end)
{
u32 len = end - start + 1;
assert(bits.PopulationCount(start, len) == len);
assert(zbits.PopulationCount(start, len) == 0);
}
}
}
{
const u32 SIZE = 258;
BitVector<SIZE> bits;
assert(bits.PopulationCount() == 0);
for (u32 i = 0; i < SIZE; ++i)
{
bits.SetBit(SIZE - i - 1);
assert(bits.PopulationCount() == i + 1);
}
assert(bits.PopulationCount() == SIZE);
for (u32 i = 0; i < SIZE; ++i)
{
bits.ClearBit(i);
assert(bits.PopulationCount() == SIZE - (i + 1));
}
}
{
BitVector<256>* bits = setup();
assert(bits->PopulationCount() == 115);
assert(bits->PopulationCount(64,96) == 51);
assert(bits->PopulationCount(5,250) == 113);
}
}
