MSCOFF32: remove dependency on druntime for long divisions

[rainers]

by calling div/mod functions from the VC runtime directly.

The ms* functions in rt.llmath can be removed if this is merged.

As we don't have an autotester for -m32mscoff: tests pass locally, but the dmd testsuite doesn't seem to exercise it that much. A bad version failed the druntime unittests, though.

[dlang-bot]

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[rainers]

@WalterBright : the OpenBSD/Solaris version calls the signed version instead, seems like a typo. see https://github.com/dlang/dmd/blob/master/src/ddmd/backend/cod1.c#L1995

[WalterBright]

I think you're right.

[WalterBright]

Unfortunately, this will fail with -betterC, which doesn't link with druntime. Perhaps add a check for -betterC to determine which to call?

[WalterBright]

Having the same object file format is only part of the battle. Each C compiler is different in how they connect to their respective runtime libraries. The only viable solution is to add switches.

[rainers]

Unfortunately, this will fail with -betterC, which doesn't link with druntime.

It will fail right now, too, as the _ms_... function are in the same module and call functions from the MS runtime. It's also just the same for other platforms calling __ULDIV__ et al.

Having the same object file format is only part of the battle. Each C compiler is different in how they connect to their respective runtime libraries. The only viable solution is to add switches.

This is about symbols in the VC runtime that are not available via dynamic linkage. An alternative would be to use lldiv instead, but that is only available since VS2013 according to MSDN (though MinGW declares it exists since VS2010).

[rainers]

Changed the calls to directly invoke the VC runtime functions. This now actually removed the dependency on druntime for long divisions for better-C.

It doesn't help replacing the C runtime, though. I've added the division functions from rt.llmath to my stub instead.