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On trunk we never generate MULX. We used to blindly use it anytime bmi2 was enabled, but its a longer encoding and isn't a guaranteed register allocation improvement. So I took it out a few weeks ago. We need a more precise heuristic for when to use it. LLVM trunk will never generate ADCX/ADOX either. This was removed in September. We used to inconsistently generate them when adx was enabled unless we could use the RMW form or the immediate form of ADC. But that didn't really make any sense. The only reason to use ADCX or ADOX is when you want to carefully manage the flags to have tw...

...t; flag "-mbmi2". > > https://github.com/Quuxplusone/WideIntProofOfConcept/blob/master/wider.h#L89-L99 > > On Clang 3.8.1 and earlier, the _addcarry_u64 and _subborrow_u64 > intrinsics required the hardware flag `-madx`, even though they didn't use > the hardware ADX/ADOX instructions. Modern GCC and Clang permit the use of > these intrinsics (to generate ADC) even in the absence of `-madx`. > > I think it would be a very good idea for Clang to support _mulx_u64 (to > generate MUL) even in the absence of `-mbmi2`. > > –Arthur > > > On Sat,...

Hi, For some maybe dumb reasons I try to write a portable version of int128. What is very valuable for this implementation is access to MUL instruction on x86 which provides full 64 x 64 -> 128 bit multiplication. An equally useful on ARM would be UMULH instruction. Well, the way you can access this on clang / GCC is to use __int128 type or use inline assembly. MSVC provides an intrinsic for

https://bugs.freedesktop.org/show_bug.cgi?id=95251 Bug ID: 95251 Summary: vdpau decoder capabilities: not supported Product: Mesa Version: 11.2 Hardware: Other OS: All Status: NEW Severity: normal Priority: medium Component: Drivers/DRI/nouveau Assignee: nouveau at