Intrinsic lowered to pseudo not preserving glue

[phoebe]

@stormeuh

If I understand correctly, I should create a new target-specific node type, e.g. RISCVISD::SHRINK_STACK, and then create patterns so that the lowering becomes:
llvm.cheri.shrink.stack.cap → RISCVISD::SHRINK_STACK → PseudoCShrinkStack.

Right.

@stormeuh

What is the purpose of inserting this node in between?
Does it need to be there for certain passes to run correctly, where just mapping the intrinsic to the pseudo broke things?

I guess because we specially handle the glue operand during MorphNode. You need a node that possesses a glue operand, which passes down it to the machine instruction. INTRINSIC_VOID doesn’t possess glue operand.