[LLVMdev] Problem with callstack/frame-index

[Per Fagrell]

Hello!

I'm trying to get stack-passed arguments working on my back-end, and I've
run into an issue I can't resolve.

I got the code working to the point that function F1 can call F2 with 5+
arguments fine (we pass 4 in registers). The problem is if F2 then calls
another function F3 with 5+ args, then all reading of the stack/call frame
is off, the address doesn't get compensated for the difference in
stack-depth. When I compile the same code with the MSP430 back end I get
something like this (pseudo-code):
f1:   sub   #4, sp
       move arg1, 0(sp)
       move arg2, 2(sp)
        ...fix registerargs...
       call f2
       ....

f2:
      sub #4, sp
      move 6(sp), arg1
      move 8(sp), arg2
       ....fix args call f3....

The important bit in that code is the 6/8 in F2. When I compile the same
code with our back-end, the offsets are 0/2, which is off by 4. Structurally
our solution mimics MSP430, and I thought I was sure we'd gotten all the
relevant parts copied and adjusted, but I can't seem to find a cure for this
offset issue! Any help greatly appreciated!

//Per
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