fix Issue 23418 - double argument is passed on stack, but assumed to …

[WalterBright]

…be in XMM0 register

I replaced the "check the generated asm" tests, because the "known good" assembler was wrong. Replaced it with a runtime check.

[dlang-bot]

Thanks for your pull request, @WalterBright!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23418	normal	double argument is passed on stack, but assumed to be in XMM0 register

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14568"

[WalterBright]

blocking #14567

[WalterBright]

@RazvanN7 @dkorpel ping

[dkorpel]

I'm trying to grasp the issue. So all this time, double parameters on 32-bit Linux with -O were completely broken, because the caller and callee were not consistent about the ABI? Would the new runnable/cdcmp.d test fail on 32-bit Linux with before this fix?

[ibuclaw]

Does this affect extern(C/C++) codegen? If so target stable.

[WalterBright]

Would the new runnable/cdcmp.d test fail on 32-bit Linux with before this fix?

Yes. Oops.

@ibuclaw I'd rather not, as this problem is blocking my further work on master with XMM code gen.

So all this time, double parameters on 32-bit Linux with -O were completely broken, because the caller and callee were not consistent about the ABI?

Ironically, most of the time it worked because the XMM0 parameter was pushed onto the stack, and yet remained in XMM0.

The bug was possible on memory models that didn't pass floating point values in XMM registers. But for the bug to appear, a set of other conditions have to be met.

[ibuclaw]

@WalterBright you can always merge stable into master immediately afterwards. In fact, I've got it pending on my release tasks, but I'm still waiting for you to reply to your emails w.r.t ftp.digitalmars.com access. :-)

[WalterBright]

I thought Jan was doing that?

[ibuclaw]

I thought Jan was doing that?

Seen no response from him so far. You are part of the wheel group though, so as a fallback admin, you can su up and add me to the group as well.

[WalterBright]

Could you email me exactly what to do? Thanks!