How jump－table representated　in DAG

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#1

Hi, all

I am interested in how jump-table representated in DAG.
I find the method visitJumpTable will Emit JumpTable node in the current MBB.
visitJumpTableHeader - This function emits necessary code to produce index in the JumpTable from switch case.
but how switch case emits?

I would like to make this clearly.

Thanks,
yaoxiao

#2

Hi Yao,

Hi, all

I am interested in how jump-table representated in DAG.
I find the method visitJumpTable will Emit JumpTable node in the current
MBB.
visitJumpTableHeader - This function emits necessary code to produce index
in the JumpTable from switch case.
but how switch case emits?

I would like to make this clearly.

It sounds like you're already looking in the right places.

The switch lowering starts in SelectionDAGBuilder::visitSwitch which
analyses the switch and decides how to lower it. For jump tables, it
calls SelectionDAGBuilder::buildJumpTable which creates and populates
the JumpTable and JumpTableHeader

Hope this helps,
Hans