On Tuesday, 5 September 2017 at 18:50:34 UTC, Johan Engelen wrote:
On Monday, 4 September 2017 at 20:39:11 UTC, Igor wrote:
I found that I can't use __simd function from core.simd under
LDC and that it has ldc.simd but I couldn't find how to
implement equivalent to this with it:
ubyte16* masks = ...;
foreach (ref c; pixels) {
c = __simd(XMM.PSHUFB, c, *masks);
}
I see it has shufflevector function but it only accepts
constant masks and I am using a variable one. Is this possible
under LDC?
You can use the module ldc.gccbuiltins_x86.di,
__builtin_ia32_pshufb128 and __builtin_ia32_pshufb256.
(also see
https://gcc.gnu.org/onlinedocs/gcc-4.4.5/gcc/X86-Built_002din-Functions.html)
Please file a feature request about shufflevector with variable
mask in our (LDC) issue tracker on Github; with some code that
you'd expect to work. Thanks.
- Johan
I'll try that this evening. Thanks! I'll also open an issue but
are you sure such feature request is valid since LLVM
shufflevector instruction, as far as I see, only supports
constant masks as well.
