Displaying 7 results from an estimated 7 matches for "getshufflecost".
2015 Jan 14
6
[LLVMdev] Instruction Cost
Hi,
I'm looking for APIs that compute instruction costs, and noticed several of
them.
1. A series of APIs of TargetTransformInfo that compute the cost of
instructions of a particular type (e.g. getArithmeticInstrCost and
getShuffleCost)
2. TargetTransformInfo::getOperationCost
3. CostModel::getInstructionCost::getInstructionCost in
lib/Analysis/CostModel.cpp
Only the first one is used extensively in LLVM's code base, but the second
and third one seems more recently added and more general, making me think
if they are designed...
2017 Feb 08
2
ShuffleKind SK_ExtractSubvector
...SK_ExtractSubvector. It seems a subvector is to be extracted, starting
from a given index of a given subtype.
First of all, if index 0 is passed, I suppose this would mean a noop?
But what about calls like the one made of LoopVectorizer for
Instruction::PHI in getInstructionCost():
return TTI.getShuffleCost(TargetTransformInfo::SK_ExtractSubvector,
VectorTy, VF - 1, VectorTy);
Here the highest index is passed, which doesn't make sense to me. Nor
does it make sense to pass the the same VectorTy in both parameters.
In BBVectorize, start index 0 is passed in one place, bu...
2015 Jan 15
2
[LLVMdev] Instruction Cost
...ogle.com> wrote:
>
>> I'm looking for APIs that compute instruction costs, and noticed several
>> of them.
>>
>> 1. A series of APIs of TargetTransformInfo that compute the cost of
>> instructions of a particular type (e.g. getArithmeticInstrCost and
>> getShuffleCost)
>> 2. TargetTransformInfo::getOperationCost
>> 3. CostModel::getInstructionCost::getInstructionCost in
>> lib/Analysis/CostModel.cpp
>>
>> Only the first one is used extensively in LLVM's code base, but the
>> second and third one seems more recently added a...
2013 Jan 10
2
[LLVMdev] ARM vectorizer cost model
...be split.
> Different targets need to implement the cases that the BasicTTI does not
> catch. For example, the cost of zext <8xi8> to <8 x i32> which is custom
> lowered on some targets.
>
I'm also thinking about the individual instructions cost
(getArithmeticInstrCost, getShuffleCost, etc). That can be a simple and
easily parallelized task. I got the A9 manual that has the cost of all
instructions (including NEON and VFP), that should give us a head start.
I'm guessing the cost you already have for Intel and the BasicTTI is in
"ideal cycle count", not taking into...
2013 Jan 10
0
[LLVMdev] ARM vectorizer cost model
On Jan 10, 2013, at 2:19 PM, Renato Golin Linaro <renato.golin at linaro.org> wrote:
> I'm also thinking about the individual instructions cost (getArithmeticInstrCost, getShuffleCost, etc). That can be a simple and easily parallelized task. I got the A9 manual that has the cost of all instructions (including NEON and VFP), that should give us a head start.
Renato,
Thanks for working on this!
Some of the costs for the arithmetic operations should be handled automatically b...
2013 Jan 09
0
[LLVMdev] ARM vectorizer cost model
Hi Renato,
> I'm interested in knowing how you'll work up the ARM cost model and how easy it'd be to split the work.
Yes, I am starting to work on the ARM cost model and I would appreciate any help in the form of: advice, performance measurements, patches, etc.
I tune the cost model by running the cost model analysis pass and I compare the output of the analysis to the output
2013 Jan 09
2
[LLVMdev] ARM vectorizer cost model
Hi Nadav,
I'm interested in knowing how you'll work up the ARM cost model and how
easy it'd be to split the work.
As far as I can see, LoopVectorizationCostModel is the class that does all
the work, with assistance from the target transform info.
Do you think that updating ARMTTI would be the best course of action now,
and inspect the differences in the CostModel later?
I also