[MLton] MLton on MinGW/win64: regression ok(ish)!

[Matthew Fluet]

On Mon, 16 Jun 2008, Nicolas Bertolotti wrote:
>> I tried to add an 'ms_abi' toggle in the amd64 codegen, but couldn't
>> figure out where to add instructions for pushing/popping the "shadow
>> space" (32 bytes) as required. I'd appreciate some help here,
>> Matthew. :-) At the moment I only have it working with the C codegen.
>> I'm hoping that using gcc only as an assembler will make the floating
>> point and ICE regressions go away.
>
> I am unfortunately unable to answer it ... and hope someone can.

<src>/mlton/codegen/amd64-codegen/amd64-generate-transfers.fun:1348 has 
code to round the C-stack to a 16byte alignment.  You could probably 
follow that code by something like:

val (setup_args, size_stack_args) =
   if convention = CFunction.Convention.MSx64
      then (AppendList.append
            (setup_args,
             AppendList.single
             (Assembly.instruction_binal
              {oper = Instruction.SUB,
               dst = c_stackP,
               src = Operand.immediate_int 32,
               size = pointerSize})),
            size_stack_args + 32)
   else (setup_args, size_stack_args)

You might also need to adjust the fixCStack instructions 
(<src>/mlton/codegen/amd64-codegen/amd64-generate-transfers.fun:1554) if 
the MSx64 ABI requires the caller to pop the C stack.

The portion of Wesley's patch that adjusts the argument registers 
depending on the ABI wasn't committed, so you would need to add that as 
well.