Error: unknown opcode cdq

[willo]

On Tuesday, 6 November 2018 at 01:47:08 UTC, kinke wrote:
> On Tuesday, 6 November 2018 at 01:13:39 UTC, willo wrote:
>> On Sunday, 4 November 2018 at 23:55:25 UTC, willo wrote:
>>> LDC inline asm doesnt like the CDQ instruction, compiles fine 
>>> on DMD. Any clues on how to get it to work?
>>
>> Great.. so cant figure it out and decide put the opcode in 
>> directly and get this....
>>
>> "Error: Data definition directives inside inline asm are not 
>> supported yet."
>>
>> *banging head on desk*
>
> To prevent a bloodshed - grep the druntime src for `__asm`. 
> That's for LLVM inline asm in AT&T syntax, check out the LLVM 
> language reference for the constraints string syntax.

Will do thanks.


> DMD-style inline asm isn't really maintained in LDC. It's 
> x86(_64) only and thus less and less interesting; GDC doesn't 
> support it at all. I also find it highly questionable whether 
> user code should really work on the asm level nowadays, e.g., 
> with architecture-neutral LLVM intrinsics (with varying 
> support) and architecture-specific GCC builtins being available 
> etc. See the LDC-specific import files in ldc/, e.g., 
> gccbuiltins_*, intrinsics, llvmasm, simd (which also allows you 
> to write code in LLVM IR for example).

Well its just what Im used to, and i've never really taken to 
intrinsics because when they first started becoming available up 
you could only do limited things with them. I mean can you branch 
on the flags after an addition? Or use stuff like the result of a 
multiply being split across EDX:EAX? Might seem like silly stuff 
but in tight loops those few cycles can make a big difference. 
Anyway I should have another look at intrinsics.