Terminators in MachineBasicBlock

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1

Hi,
Why does a MachineBasicBlock have multiple terminator instructions (unlike BasicBlock, which can only have one) ?
Thanks,
Tom

2

Hi,

Hi,
Why does a MachineBasicBlock have multiple terminator instructions (unlike BasicBlock, which can only have one) ?

Think of it as predicated instructions.
E.g.,
bool = icmp
if bool : br if
br else

As for why, we could indeed have split those terminators into several basic blocks, but it would have required more MachineBasicBlock objects.

Cheers,
-Quentin

3

So in your example there are two terminators in the basic block (br if and br else)?

4

So in your example there are two terminators in the basic block (br if and br else)?

Yes.