For stabs to work, it needs FRAME_LOCALS_ADDRESS(); and
FRAME_LOCALS_ADDRESS() relies on the prologue analyzer (since frame ID
won't correspond to `frame-base') for the computation of the correct
value; and that means unwinding the same frame two ways. Outch.
Yeah...
- if we have CFI use it to find the frame address. Does this
become the frame ID?
- if we have dwarf2 debug and CFI, then we don't need to do prologue
analysis; CFI should give us everything we need
- if we have stabs debug and CFI, then we do need to do prologue
analysis to get FRAME_LOCALS_ADDRESS
- if we have either kind of debug info and no CFI then we need to do
prologue analysis; for dwarf2 we'll also need to calculate the frame
base from DW_AT_frame_base in order to use it to find locals
Is that about right?