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Hello,
import std, core.simd;
void main()
{
enum ubyte16
good1 = mixin([1, 2, 3, 4]),
bad = [1, 2, 3, 4];
static immutable ubyte16
good2 = mixin([1, 2, 3, 4]),
crash = [1, 2, 3, 4];
pragma(msg, good1);
pragma(msg, bad);
pragma(msg, good2);
pragma(msg, crash);
}
In the above example I tried 4 ways to initialize ubyte16 constants.
I only specify the first 4 values, the remaining is automatically zero.
2 of them are good 2 of them are bad.
Egy enum version compiles, but after trying SSE pshufb instruction with them, it seems like the [1, 2, 3, 4, 12 times 0] is distorted to this: [1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4]
I discovered the mixin() trick when I wanted to give them some calculated series.
Is it a bad way to initialize these constants? Is there a better way?
cast(immutable(__vector(ubyte[16])))[cast(ubyte)1u, cast(ubyte)2u, cast(ubyte)3u, cast(ubyte)4u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u, cast(ubyte)0u]
This is how the compiler dumps it. But it's not so compact, so I rather use the mixin() version, I just don't understand why the int array fails -> [1, 2, 3....] It would look so nice.
