/// MachineBasicBlock, an alignment (if present) and a comment describing
/// it if appropriate.
void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
+ // Emit an alignment directive for this block, if needed.
if (unsigned Align = MBB->getAlignment())
EmitAlignment(Log2_32(Align));
+ // If the block has its address taken, emit a special label to satisfy
+ // references to the block. This is done so that we don't need to
+ // remember the number of this label, and so that we can make
+ // forward references to labels without knowing what their numbers
+ // will be.
if (MBB->hasAddressTaken()) {
GetBlockAddressSymbol(MBB->getBasicBlock()->getParent(),
MBB->getBasicBlock())->print(O, MAI);
O << '\n';
}
+ // Print the main label for the block.
if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
if (VerboseAsm)
O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
O << '\n';
}
+ // Print some comments to accompany the label.
if (VerboseAsm) {
if (const BasicBlock *BB = MBB->getBasicBlock())
if (BB->hasName()) {