Cranelift: Adjust virtual SP after tail
call-conv callees return
#6586
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Callees that use the
tail
calling convention will pop stack arguments from the stack for their callers. They do not, however, adjust the caller's virtual SP, so that still needs to happen in our ABI andCallSite
code. This is, however, slightly trickier than just emitting a nominal SP adjustment pseudo-instruction because we cannot let regalloc attempt to spill or reload values between the call and the SP adjustment because the stack offsets will be off by the size of the stack arguments to the call. Therefore, we add the number of bytes that the callee pops to theCallInfo
structures and have emission update the virtual SP atomically with regards to the call itself.Fixes #6581
Fixes #6582