+ // Figure out how large the NewMBB is. As the second half of the original
+ // block, it may contain a tablejump.
+ unsigned NewBBSize = 0;
+ for (MachineBasicBlock::iterator I = NewBB->begin(), E = NewBB->end();
+ I != E; ++I)
+ NewBBSize += TII->GetInstSizeInBytes(I);
+ // Set the size of NewBB in BBSizes. It does not include any padding now.
+ BBSizes[NewBBI] = NewBBSize;
+
+ MachineInstr* ThumbJTMI = prior(NewBB->end());
+ if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) {
+ // We've added another 2-byte instruction before this tablejump, which
+ // means we will always need padding if we didn't before, and vice versa.
+
+ // The original offset of the jump instruction was:
+ unsigned OrigOffset = BBOffsets[OrigBBI] + BBSizes[OrigBBI] - delta;
+ if (OrigOffset%4 == 0) {
+ // We had padding before and now we don't. No net change in code size.
+ delta = 0;
+ } else {
+ // We didn't have padding before and now we do.
+ BBSizes[NewBBI] += 2;
+ delta = 4;
+ }
+ }
+