Displaying 7 results from an estimated 7 matches similar to: "KNL Assembly Code for Matrix Multiplication"
2017 Jun 24
4
AVX Scheduling and Parallelism
Hello,
After generating AVX code for large no of iterations i came to realize that
it still uses only 2 registers zmm0 and zmm1 when the loop urnroll
factor=1024,
i wonder if this register allocation allows operations in parallel?
Also i know all the elements within a single vector instruction are
computed in parallel but does the elements of multiple instructions
computed in parallel? like are
2017 Jun 25
2
AVX Scheduling and Parallelism
Hi Ahmed,
>From what can be seen in the code snippet you provided, the reuse of XMM0 and XMM1 across loop-unroll instances does not inhibit instruction-level parallelism.
Modern X86 processors use register renaming that can eliminate the dependencies in the instruction stream. In the example you provided, the processor should be able to identify the 2-vloads + vadd + vstore sequences as
2017 Jun 25
0
AVX Scheduling and Parallelism
Hi, Zvi,
I agree. In the context of targeting the KNL, however, I'm a bit
concerned about the addressing, and specifically, the size of the
resulting encoding:
> vmovdqu32 zmm0, zmmword ptr [rax + c+401280] ;load b[401280] in
> zmm0
>
> vpaddd zmm1, zmm1, zmmword ptr [rax + b+401344]
> ; zmm1<-zmm1+b[401344]
The KNL can only
2017 Jan 24
7
[X86][AVX512] RFC: make i1 illegal in the Codegen
Hi All,
AVX-512 introduced the K mask registers and masked operations which make a natural choice for legalizing vectors of i1's.
For example,
define <8 x i32> @foo(<8 x i32>%a, <8 x i32*> %p) {
%r = call <8 x i32> @llvm.masked.gather.v8i32(<8 x i32*> %p, i32 4, <8 x i1> <i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true>,
2017 Aug 06
2
VBROADCAST Implementation Issues
i want to implement gather for v64i32. i wrote following code.
def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst), (ins
i2048mem:$src),
"GATHER_256B\t{$src, $dst|$dst, $src}",
[(set VR_2048:$dst, (v64i32 (masked_gather
addr:$src)))],
IIC_MOV_MEM>, TA;
def: Pat<(v64f32 (masked_gather addr:$src)), (GATHER_256B
2017 Aug 07
2
VBROADCAST Implementation Issues
Hello,
I did as you said,
Please tell me whether the following correct now??
def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst, _.KRCWM:$mask_wb),
(VR_2048:$src1, _.KRCWM:$mask, ins i2048mem:$src2),
"GATHER_256B\t{$src2, {$dst}{${mask}}|${dst} {${mask}},
$src2}"),
[(set VR_2048:$dst, _.KRCWM:$mask_wb, (v64i32
(GatherNode
2017 Aug 07
3
VBROADCAST Implementation Issues
Thank You. Still getting errors.I have modified my instructions as you said
as follows:
def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst, VK64WM:$mask_wb),
(ins VR_2048:$src1, VK64WM:$mask, i2048mem:$src2),
"GATHER_256B\t{$src2, {$dst} {${mask}}|${dst}
{${mask}}, $src2}",
[(set VR_2048:$dst, VK64WM:$mask_wb, (v64i32
(masked_gather