Displaying 7 results from an estimated 7 matches for "handlefloatingpointiv".
2016 May 18
4
Working on FP SCEV Analysis
On Tue, May 17, 2016 at 8:49 PM Owen Anderson <resistor at mac.com> wrote:
>
> On May 16, 2016, at 2:42 PM, Sanjoy Das via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
> - Core motivation: why do we even care about optimizing floating
> point induction variables? What situations are they common in? Do
> programmers _expect_ compilers to optimize them
2016 May 20
5
Working on FP SCEV Analysis
...proach taken by Elena.
Elena thinks this solution ”looks very structured”.
If I’m not mistaken, some people think this is overkill and overly complicates already complicated SCEV.
Anyone care to look at the patch Elena came up with?
2)
IndVarSimplify::handleFloatingPointIV (mentioned by Andy)
This transforms integer-valued FP (primary) IV into integer IV and convert.
Chandler says most of Graphics shading language use case mentioned by Owen
should be handled here.
It certainly has the logic of detecting...
2016 May 20
0
Working on FP SCEV Analysis
...t; Elena thinks this solution ”looks very structured”.
> If I’m not mistaken, some people think this is overkill and overly complicates already complicated SCEV.
> Anyone care to look at the patch Elena came up with?
> 2)
> IndVarSimplify::handleFloatingPointIV (mentioned by Andy)
> This transforms integer-valued FP (primary) IV into integer IV and convert.
> Chandler says most of Graphics shading language use case mentioned by Owen
> should be handled here.
> It certainly has th...
2016 May 19
3
Working on FP SCEV Analysis
...IEEE
semantics so this looks like normal algabra etc:
> for (float f = 0.01f; f < 1.0f; f += 0.01f) ç **A**
...
> I'd rather see us cleverly turn it into:
> float f = 0.01f;
> for (int i = 1; i < 100; i += 1, f += 0.01f) ç **B**
I can later try to enhance IndVarSimplify::handleFloatingPointIV() in
order to convert**A** to **B**.
But **B** is exactly the case I’m starting from. The main IV “i” is
integer. The variable “f” is also considered as IV in this loop.
And this loop is not vectorized because “f” is floating point.
I don’t think that the case **B** is uncommon.
If B is the cas...
2016 May 18
4
Working on FP SCEV Analysis
...> > for (float f = 0.01f; f < 1.0f; f += 0.01f) ç **A**
>
> ...
>
> > I'd rather see us cleverly turn it into:
>
> > float f = 0.01f;
>
> > for (int i = 1; i < 100; i += 1, f += 0.01f) ç **B**
>
> I can later try to enhance IndVarSimplify::handleFloatingPointIV() in
> order to convert**A** to **B**.
>
> But **B** is exactly the case I’m starting from. The main IV “i” is
> integer. The variable “f” is also considered as IV in this loop.
>
> And this loop is not vectorized because “f” is floating point.
>
> I don’t think that the cas...
2016 May 24
1
Working on FP SCEV Analysis
...Elena thinks this solution ”looks very structured”.
> If I’m not mistaken, some people think this is overkill and
> overly complicates already complicated SCEV.
> Anyone care to look at the patch Elena came up with?
> 2)
> IndVarSimplify::handleFloatingPointIV (mentioned by Andy)
> This transforms integer-valued FP (primary) IV into integer
> IV and convert.
> Chandler says most of Graphics shading language use case
> mentioned by Owen
> should be handled here.
> It certai...
2016 May 16
6
Working on FP SCEV Analysis
[+CC Andy]
Hi Elena,
I don't have any fundamental issues with teaching SCEV about floating
point types, but given this will be a major change, I think a high
level roadmap should be discussed on llvm-dev before we start
reviewing and committing changes.
Here are some issues that I think are worth discussing:
- Core motivation: why do we even care about optimizing floating
point