Displaying 2 results from an estimated 2 matches for "lowervector_shuffle_4wide".
2009 Dec 17
2
[LLVMdev] AVX Shuffles & PatLeaf Help Needed
I'm working on debugging AVX shuffles and I ran into an interesting
problem.
The current isSHUFPMask predicate in X86ISelLowering needs to be
generalized to operate on 128-bit or 256-bit masks. There are
probably lots of other things to change too (LowerVECTOR_SHUFFLE_4wide,
etc.) but I'll worry about that later.
The generalized rule is:
1. For the low 64 bits of the result vector, the source can be from
the low 128 bits of vector 1.
2. For the next 64 bits, the source can be from the low 128 bits of
vector 2.
3. For the 3rd 64 bits, the source is the hi...
2009 Dec 17
0
[LLVMdev] AVX Shuffles & PatLeaf Help Needed
...Greene wrote:
> I'm working on debugging AVX shuffles and I ran into an interesting
> problem.
>
> The current isSHUFPMask predicate in X86ISelLowering needs to be
> generalized to operate on 128-bit or 256-bit masks. There are
> probably lots of other things to change too (LowerVECTOR_SHUFFLE_4wide,
> etc.) but I'll worry about that later.
>
> The generalized rule is:
>
> 1. For the low 64 bits of the result vector, the source can be from
> the low 128 bits of vector 1.
>
> 2. For the next 64 bits, the source can be from the low 128 bits of
> vector 2.
&g...