[CDG5] MPW code mysteries

[Max Poliakovski]

Fellow hackers,

I'm currently trying to get MPW 3.5 (from EMPW) to generate code closely
resembling the original Trampoline.

While doing so, I immediately stumbled across two issues I cannot resolve.
I must admit that my MPW skills are limited. I therefore hope to get some
help from you.

1) Trampoline's startup code initializes the RTOC as follows:

    mflr r11
    bl setup_rtoc
    DC.L 0x1001E8
setup_rtoc:
    mflr RTOC
    lwz RTOC, 0(RTOC)

The word in the 3rd line contains the base address of TOC. The value shown
above is from Apple's binary. I replaced it with DC.L TOC[TC0] to make
PPCAsm/PPCLink to stuff the correct value there. That unfortunately doesn't
work. PPCAsm says:

### Warning 3171 ### Treating 'TOC[TC0]' as a csect relative offset. Make
sure to add it to its csect's TOC entry.

I don't understand this message. What do I need to put there in order to
get the base address of TOC placed there?

2) Trampoline's main() initializes the pointer to OF client interface right
at the beginning. The code of interest looks like that:

lwz r9, CIPtr_TC(RTOC)
lisori r3, 0xdeadbeef
stw r5, 0(r9)
stw r3, 4(r9)

The pointer to the OF client dispatcher is in R5 (3rd argument of main).
The TOC pointer is initialized to 0xDEADBEEF. That's exactly what I cannot
reproduce. I defined a correct function pointer like that:

typedef long (*OfCiPtr)(CIArgs *args);
static OfCIPtr gCIPtr;

void main(int argc, int arg[], OfCiPtr ciPtr)
{
    gCIPtr = ciPtr;
}

When I initialize that global pointer gCIPtr with value from ciPtr (3rd
argument), only the function address is written while the TOC value remains
untouched. The compiled code looks like that:

lwz r9, CIPtr_TC(RTOC)
stw r5, 0(r9)

I wonder how Apple guys managed to put 0xDEADBEEF into TVector's TOC? Do
you have any clue?
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