Re: [PATCH v2 1/2] Fix function argument and return value locations

[Simon Marchi <simark@simark.ca>]

On 2020-05-29 11:07 a.m., Hannes Domani via Gdb-patches wrote:
> Fixes these testsuite fails on Windows:
> FAIL: gdb.base/callfuncs.exp: p t_float_complex_values(fc1, fc2)
> FAIL: gdb.base/callfuncs.exp: p t_float_complex_many_args(fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4)
> FAIL: gdb.base/callfuncs.exp: noproto: p t_float_complex_values(fc1, fc2)
> FAIL: gdb.base/callfuncs.exp: noproto: p t_float_complex_many_args(fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4, fc1, fc2, fc3, fc4)
> FAIL: gdb.base/call-sc.exp: p/c fun(); call call-sc-tld
> FAIL: gdb.base/call-sc.exp: advance to fun for return; return call-sc-tld
> FAIL: gdb.base/call-sc.exp: zed L for return; return call-sc-tld
> FAIL: gdb.base/call-sc.exp: return foo; return call-sc-tld
> FAIL: gdb.base/call-sc.exp: return foo; synchronize pc to main() for 'call-sc-tld'
> FAIL: gdb.base/call-sc.exp: return foo; synchronize pc to main() for 'call-sc-tld'
> FAIL: gdb.base/call-sc.exp: advance to fun for finish; return call-sc-tld
> FAIL: gdb.base/call-sc.exp: zed L for finish; return call-sc-tld
> FAIL: gdb.base/call-sc.exp: finish foo; return call-sc-tld (the program is no longer running)
> FAIL: gdb.base/call-sc.exp: value foo finished; return call-sc-tld
>
> For function arguments (callfuncs.exp), only TYPE_CODE_COMPLEX was
> missing in the types passed via integer registers.
>
> For return values, there were a lot more issues:
> - TYPE_CODE_DECFLOAT is NOT returned via XMM0.
> - long double is NOT returned via XMM0.
> - but __int128 IS returned via XMM0.
> - the comments for TYPE_CODE_FLT state that __m128, __m128i and __m128d are
>   returned by XMM0, and this is correct, but it doesn't actually check for
>   them, because they are TYPE_CODE_ARRAY with TYPE_VECTOR
>
> So I had to add TYPE_CODE_DECFLOAT to the arguments passed via XMM register,
> but I had to remove it from the values returned via XMM0 register.

I won't pretend I cross-checked all of this with the ABI documentation,
but that looks good to me.  If you say the tests now pass, that gives me
enough confidence, so please go ahead and merge.

Simon