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Re: Vector TG meeting minutes 2020/4/03
These are basic operations, not application kernels.
It's easy to call out missing instructions when considering individual
operations.
It's more important to gather and evaluate actual application
These are basic operations, not application kernels.
It's easy to call out missing instructions when considering individual
operations.
It's more important to gather and evaluate actual application
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By
Krste Asanovic
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#87
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the usage of Vector AMO Operations
Hi, all
I have a problem about the usage of VectorAMO Operations. In the spec, there is only two sentences to describe the usageof Vector AMO Operations. Who have the concrete sample or other
Hi, all
I have a problem about the usage of VectorAMO Operations. In the spec, there is only two sentences to describe the usageof Vector AMO Operations. Who have the concrete sample or other
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By
Linjie Yu
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#86
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Re: 答复: [RISC-V] [tech-vector-ext] Vector TG meeting minutes 2020/4/03
Hi, Nick
That is a good suggestion for my code, thank you very much. But I develop my code depend on spec 0.7.1. The q-wide instructions had not been added to the spec. And I am confused with the
Hi, Nick
That is a good suggestion for my code, thank you very much. But I develop my code depend on spec 0.7.1. The q-wide instructions had not been added to the spec. And I am confused with the
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By
Linjie Yu
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#85
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Re: 答复: [RISC-V] [tech-vector-ext] Vector TG meeting minutes 2020/4/03
I agree with your point. But nowadays, the spec is not stable, and there is no target SOC to verify it. So, in my opinion, the number of instructions is an important indicator at present.
发件人:
I agree with your point. But nowadays, the spec is not stable, and there is no target SOC to verify it. So, in my opinion, the number of instructions is an important indicator at present.
发件人:
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By
Linjie Yu
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#84
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Re: Vector TG meeting minutes 2020/4/03
Hi Damon,
Thanks for providing a concrete example!
I think you can improve the performance of your first example (non-widening loads). Instead of immediately widening, you could instead perform your
Hi Damon,
Thanks for providing a concrete example!
I think you can improve the performance of your first example (non-widening loads). Instead of immediately widening, you could instead perform your
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By
Nick Knight
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#83
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Re: Vector TG meeting minutes 2020/4/03
The number of instructions does not necessarily correspond to the speed, and especially not to the PPA or efficiency. Making the load/store simpler might save enough area to make it as or more energy
The number of instructions does not necessarily correspond to the speed, and especially not to the PPA or efficiency. Making the load/store simpler might save enough area to make it as or more energy
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By
Bruce Hoult
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#82
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Re: 答复: [RISC-V] [tech-vector-ext] Vector TG meeting minutes 2020/4/03
Hi,all
I have some applications about byte/halfword/word vector load/stores, like
gemm, direct convolution and son on.
For 3x3 direct convolution, the code without byte/halfword/word
Hi,all
I have some applications about byte/halfword/word vector load/stores, like
gemm, direct convolution and son on.
For 3x3 direct convolution, the code without byte/halfword/word
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By
Linjie Yu
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#81
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Re: Vector TG meeting minutes 2020/4/03
I agree Nick.
So here is a suggestion, not completely facetiously:
For load byte/half/word
example when SEW = 64
An implementation can
I agree Nick.
So here is a suggestion, not completely facetiously:
For load byte/half/word
example when SEW = 64
An implementation can
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By
David Horner
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#80
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Re: Vector TG meeting minutes 2020/4/03
In scalar code, there is always signed/zero extension for the data and alignment. I do not see a different with vector load/store. If alignment is needed, not much additional cost for signed/zero
In scalar code, there is always signed/zero extension for the data and alignment. I do not see a different with vector load/store. If alignment is needed, not much additional cost for signed/zero
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By
Thang Tran
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#79
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Re: Vector TG meeting minutes 2020/4/03
Bob Dreyer said he would share an example code.
Do you really have a 2x or 4x wider write port to the vector register file to make vlb and the like work at full memory bandwidth?
If yes, what is the
Bob Dreyer said he would share an example code.
Do you really have a 2x or 4x wider write port to the vector register file to make vlb and the like work at full memory bandwidth?
If yes, what is the
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By
Alex Solomatnikov
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#78
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Re: Vector TG meeting minutes 2020/4/03
Hi Nick,
It is confidential customer application code.
Thanks, Thang
Hi Nick,
It is confidential customer application code.
Thanks, Thang
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By
Thang Tran
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#77
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Re: Vector TG meeting minutes 2020/4/03
Hi Thang,
Can you, and anyone else who responds, please be concrete about the applications you have in mind? I tried to do so in my email.
In my opinion, concrete examples are crucial to making an
Hi Thang,
Can you, and anyone else who responds, please be concrete about the applications you have in mind? I tried to do so in my email.
In my opinion, concrete examples are crucial to making an
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By
Nick Knight
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#76
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Re: Vector TG meeting minutes 2020/4/03
There are real application (mixed integer/FP - convert instruction is used) codes written with load/store byte/halfword/word. There is a huge performance impact by adding widening instruction in a
There are real application (mixed integer/FP - convert instruction is used) codes written with load/store byte/halfword/word. There is a huge performance impact by adding widening instruction in a
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By
Thang Tran
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#75
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Re: Vector TG meeting minutes 2020/4/03
On GitHub, this is Issue #362.
While I'm generally in favor of dropping them, I am aware it will pose a challenge to several applications if, additionally, indexed loads and stores switch to
On GitHub, this is Issue #362.
While I'm generally in favor of dropping them, I am aware it will pose a challenge to several applications if, additionally, indexed loads and stores switch to
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By
Nick Knight
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#74
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Vector TG meeting minutes 2020/4/03
Date: 2020/4/03
Task Group: Vector Extension
Chair: Krste Asanovic
Number of Attendees: ~15
Current issues on github: https://github.com/riscv/riscv-v-spec
Issues discussed: #354/362
The following
Date: 2020/4/03
Task Group: Vector Extension
Chair: Krste Asanovic
Number of Attendees: ~15
Current issues on github: https://github.com/riscv/riscv-v-spec
Issues discussed: #354/362
The following
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By
Krste Asanovic
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#73
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meeting reminder
We will be meeting again this morning.
I hope to focus on closing on features for upcoming 0.9 release.
Krste
We will be meeting again this morning.
I hope to focus on closing on features for upcoming 0.9 release.
Krste
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By
Krste Asanovic
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#72
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Re: A couple of questions about the vector spec
Yes - agreed. I believe it is going to be considered for support in the 64 bit encoding.
Best regards
Nagendra
Yes - agreed. I believe it is going to be considered for support in the 64 bit encoding.
Best regards
Nagendra
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By
Nagendra Gulur
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#71
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Re: A couple of questions about the vector spec
On #2, it would require finding a 2 bit field in the vector load format to encode "no-scaling/2/4/8". Not trivial within the 32b format.
On Wed, Mar 11, 2020 at 1:30 AM Nagendra Gulur
On #2, it would require finding a 2 bit field in the vector load format to encode "no-scaling/2/4/8". Not trivial within the 32b format.
On Wed, Mar 11, 2020 at 1:30 AM Nagendra Gulur
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By
Roger Espasa
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#70
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Re: A simple fractional LMUL proposal
On 2020-03-24 11:40 p.m., Krste Asanovic wrote: I attempt to summarize the needs here:
1) to reduce the register pressure that successive levels of LMUL invoke
(halving
On 2020-03-24 11:40 p.m., Krste Asanovic wrote: I attempt to summarize the needs here:
1) to reduce the register pressure that successive levels of LMUL invoke
(halving
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By
David Horner
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#69
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Re: Vector Indexed Loads - Partial Return?
Not really challenge :-) But it's the only option if you can't / don't want to add a "vstart" equivalent (because you don't want to save/restore it...)
@Nagendra: note that the spec does require the
Not really challenge :-) But it's the only option if you can't / don't want to add a "vstart" equivalent (because you don't want to save/restore it...)
@Nagendra: note that the spec does require the
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By
Roger Espasa
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#68
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