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<div class="moz-cite-prefix">On 02/27/2017 06:29 AM, Nema, Ashutosh
wrote:<br>
</div>
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<div class="WordSection1">
<p class="MsoNormal">Thanks for looking into this.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">1) Issues with re running vectorizer:<o:p></o:p></p>
<p class="MsoNormal">Vectorizer might generate redundant alias
checks while vectorizing epilog loop.<o:p></o:p></p>
<p class="MsoNormal">Redundant alias checks are expensive, we
like to reuse the results of already computed alias checks.<o:p></o:p></p>
<p class="MsoNormal">With metadata we can limit the width of
epilog loop, but not sure about reusing alias check result.<o:p></o:p></p>
<p class="MsoNormal">Any thoughts on rerunning vectorizer with
reusing the alias check result ?</p>
</div>
</blockquote>
<br>
One way of looking at this is: Reusing the alias-check result is
really just a conditional propagation problem; if we don't already
have an optimization that can combine these after the fact, then we
should.<br>
<br>
-Hal<br>
<br>
<blockquote
cite="mid:CY4PR12MB17993414B37BDE99294FD69FFB570@CY4PR12MB1799.namprd12.prod.outlook.com"
type="cite">
<div class="WordSection1">
<p class="MsoNormal"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">2) Best & worst case for epilog
vectorization.<o:p></o:p></p>
<p class="MsoNormal">Epilog vectorization incurs additional cost
of checks which decides to execute either epilog vector loop
or scalar loop.<o:p></o:p></p>
<p class="MsoNormal">These checks are:<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l0 level1 lfo2"><!--[if !supportLists]--><span
style="mso-list:Ignore">a)<span style="font:7.0pt
"Times New Roman"">
</span></span><!--[endif]-->Min trip count check for epilog
vector loop.<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l0 level1 lfo2"><!--[if !supportLists]--><span
style="mso-list:Ignore">b)<span style="font:7.0pt
"Times New Roman"">
</span></span><!--[endif]-->Alias result check (only if
alias check is generated for first vector version)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Where the epilog vector trip count is large
epilog vectorization with profitable width likely to give
gain. Worst case probably after these additional checks
executing the scalar loop.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">3) Benchmarking & results:<o:p></o:p></p>
<p class="MsoNormal">We have observed 4% improvement in one of
our internal benchmark.<o:p></o:p></p>
<p class="MsoNormal">Tried CPU2006 and didn’t found any degrade
& improvements.<o:p></o:p></p>
<p class="MsoNormal">On code size increase I have not yet
verified yet will check and get back.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">4) What should be the minimum first vector
loop width to enable epilog vectorization.<o:p></o:p></p>
<p class="MsoNormal">This count should not be small as it may
degrade the performance, with my limited tests I have observed
16 is a point it shows gains with one of our internal
benchmark. This require more experiments & testing to
decide what should be the minimum width.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">5) Unrolling issues:<o:p></o:p></p>
<p class="MsoNormal">As Ayal mentioned with large unroll factor
the next profitable EpilogVF could be equal to VF.<o:p></o:p></p>
<p class="MsoNormal">With the same reason the current patch
enforces UF=1, as unrolling can minimize the possibility of
executing epilog vector loop.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Example to understand the new layout:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">void foo (char *A, char *B, char *C, int
len) {<o:p></o:p></p>
<p class="MsoNormal"> int i = 0;<o:p></o:p></p>
<p class="MsoNormal"> for (i=0 ; i< len; i++)<o:p></o:p></p>
<p class="MsoNormal"> A[i] = B[i] + C[i];<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This loop get vectorize with width 32 and
epilog loop get vectorized with width 8.<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l1 level1 lfo4"><!--[if !supportLists]--><span
style="mso-list:Ignore">a)<span style="font:7.0pt
"Times New Roman"">
</span></span><!--[endif]-->Please check attached
IR(test.ll)<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l1 level1 lfo4"><!--[if !supportLists]--><span
style="mso-list:Ignore">b)<span style="font:7.0pt
"Times New Roman"">
</span></span><!--[endif]-->To understand how alias check
result got used, check temporary “acr.val” usage.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">Ashutosh<span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #E1E1E1
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">From:</span></b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">
Zaks, Ayal [<a class="moz-txt-link-freetext" href="mailto:ayal.zaks@intel.com">mailto:ayal.zaks@intel.com</a>]
<br>
<b>Sent:</b> Sunday, February 26, 2017 10:53 PM<br>
<b>To:</b> Hal Finkel <a class="moz-txt-link-rfc2396E" href="mailto:hfinkel@anl.gov"><hfinkel@anl.gov></a>; Adam
Nemet <a class="moz-txt-link-rfc2396E" href="mailto:anemet@apple.com"><anemet@apple.com></a>; Nema, Ashutosh
<a class="moz-txt-link-rfc2396E" href="mailto:Ashutosh.Nema@amd.com"><Ashutosh.Nema@amd.com></a><br>
<b>Cc:</b> llvm-dev <a class="moz-txt-link-rfc2396E" href="mailto:llvm-dev@lists.llvm.org"><llvm-dev@lists.llvm.org></a><br>
<b>Subject:</b> RE: [llvm-dev] [Proposal][RFC] Epilog
loop vectorization<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">+1
for “</span>just rerun the vectorizer<span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">”
on the scalar remainder loop, as the proposed decision
process is broken down into “first determine best VF for
main loop, then determine best next EpilogVF for remainder
loop” anyhow:<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> const
LoopVectorizationCostModel::VectorizationFactor EpilogVF =<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">
CM.identifyNextProfitableVF(VF.Width);<o:p></o:p></span></p>
<p class="MsoNormal"><a moz-do-not-send="true"
name="_MailEndCompose"></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Raising
some aspects:<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">o
The unroll factor may also affect the best EpilogVF. For
instance, if UF=1 then EpilogVF < VF, as the patch
currently enforces. But if UF is larger the next profitable
EpilogVF could be equal to VF.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">o
The scalar loop serves two purposes, as determined by its
two pre-headers: either as a default in case runtime
dependence checks fail, or as a remainder loop in which case
it is known to be vectorizable with trip count less-than
VF*UF (or equal-to it*). Would be good to keep this in mind
when rerunning.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">(*)
Note that if original loop requiresScalarEpilogue(), the
trip count of the remainder loop may be equal to VF*UF,
and/or the vectorized remainder loop may too require a
scalar epilogue.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">o
It should be interesting to see how a single masked
iteration that uses the original VF, say for UF=1, works. LV
should hopefully already support most of what’s needed.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">o
The original Trip Count clearly affects the profitability of
vectorizing the remainder loop. Would be good to leverage
any information that can be derived about TC either
statically or based on profiling, when determining EpilogVF.
Potential speedups and overheads/slowdowns could possibly be
demonstrated using extreme cases; what would the best and
worst cases be? Perhaps TinyTripCountVectorThreshold is also
affected?<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">o
Finally, VPlan is currently modeling how to vectorize the
loop body according to the potentially profitable VF’s. It’s
modelling could be used to generate vector code for both
body and remainder, and to consider their combined, overall
cost.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Ayal.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #E1E1E1
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><a moz-do-not-send="true"
name="_____replyseparator"></a><b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">From:</span></b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">
llvm-dev [</span><a moz-do-not-send="true"
href="mailto:llvm-dev-bounces@lists.llvm.org"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">mailto:llvm-dev-bounces@lists.llvm.org</span></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">]
<b>On Behalf Of </b>Hal Finkel via llvm-dev<br>
<b>Sent:</b> Friday, February 24, 2017 00:14<br>
<b>To:</b> Adam Nemet <</span><a
moz-do-not-send="true" href="mailto:anemet@apple.com"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">anemet@apple.com</span></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">>;
Nema, Ashutosh <</span><a moz-do-not-send="true"
href="mailto:Ashutosh.Nema@amd.com"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">Ashutosh.Nema@amd.com</span></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">><br>
<b>Cc:</b> llvm-dev <</span><a moz-do-not-send="true"
href="mailto:llvm-dev@lists.llvm.org"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">llvm-dev@lists.llvm.org</span></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext">><br>
<b>Subject:</b> Re: [llvm-dev] [Proposal][RFC] Epilog
loop vectorization<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p><o:p> </o:p></p>
<div>
<p class="MsoNormal">On 02/22/2017 11:52 AM, Adam Nemet via
llvm-dev wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<p class="MsoNormal">Hi Ashutosh,<o:p></o:p></p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<p class="MsoNormal">On Feb 22, 2017, at 1:57 AM, Nema,
Ashutosh via llvm-dev <<a moz-do-not-send="true"
href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>>
wrote:<o:p></o:p></p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Hi,</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">This
is a proposal about epilog loop vectorization.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Currently
Loop Vectorizer inserts an epilogue loop for
handling loops that don’t have known iteration
counts.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">The
Loop Vectorizer supports loops with an unknown
trip count, unknown trip count may not be a
multiple of the vector width, and the vectorizer
has to execute the last few iterations as scalar
code. It keeps a scalar copy of the loop for the
remaining iterations.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Loop
with the large width has a high possibility of
executing many scalar iterations.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">i.e.
i8 data type with 256bits target register can
vectorize with vector width 32, with that maximum
trip count possibility for scalar(epilog) loop is
31, which is significant & worth vectorizing.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Large
vector factor has following challenges:</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:.5in">
<p class="MsoNormal" style="text-indent:-.25in"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif">1)</span><span
style="font-size:7.0pt"> <span
class="apple-converted-space"> </span></span><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Possibility
of remainder iteration is substantial.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:.5in">
<p class="MsoNormal" style="text-indent:-.25in"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif">2)</span><span
style="font-size:7.0pt"> <span
class="apple-converted-space"> </span></span><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Actual
trip count at runtime is substantial but not
meeting minimum trip count to execute vector loop.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">These
challenges can be addressed by mask instructions,
but these instructions are limited and may not be
available to all targets.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">By
epilog vectorization our aim to vectorize epilog
loop where original loop is vectorized with large
vector factor and has a high possibility of
executing scalar iterations.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">This
require following changes:</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:.5in">
<p class="MsoNormal" style="text-indent:-.25in"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif">1)</span><span
style="font-size:7.0pt"> <span
class="apple-converted-space"> </span></span><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Costing:
Preserve all profitable vector factor.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:.5in">
<p class="MsoNormal" style="text-indent:-.25in"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif">2)</span><span
style="font-size:7.0pt"> <span
class="apple-converted-space"> </span></span><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Transform:
Create an additional vector loop with next
profitable vector factor.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
</div>
</blockquote>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Is this something that you propose to
be on by default for wide VPU architectures without
masking support? I.e. how widely is this applicable?
If not then perhaps a better strategy would be to just
annotate the remainder loop with some metadata to limit
the vectorization factor and just rerun the vectorizer.<o:p></o:p></p>
</div>
</div>
</blockquote>
<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
Why would this solution (annotating the remainder loop to
limit vectorization and rerunning the vectorization process)
not be preferred regardless?<br>
<br>
One issue that might be relevant here are runtime aliasing
checks, which are probably going to be redundant, or partially
redundant, between the different vectorized versions. Will we
be able to do any necessary cleanup after the fact? Moreover,
we often don't hoist (unswitch) these checks out of inner
loops (perhaps because they're inside the trip-count checks?);
I wonder if the proposed block structure will make this
situation better or worse (or have no overall effect).<br>
<br>
Thanks again,<br>
Hal<br>
<br>
<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Adam<o:p></o:p></p>
</div>
<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Please
refer attached file (BlockLayout.png) for the
details about transformed block layout.</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Patch
is available at:<span
class="apple-converted-space"> </span></span><a
moz-do-not-send="true"
href="https://reviews.llvm.org/D30247"><span
style="font-size:11.0pt;font-family:"Lucida
Sans
Unicode",sans-serif;color:#954F72;background:white">https://reviews.llvm.org/D30247</span></a><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white"> </span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Regards,</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Lucida
Sans Unicode",sans-serif;background:white">Ashutosh</span><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<p class="MsoNormal"><BlockLayout.png><span
style="font-size:9.0pt;font-family:"Helvetica",sans-serif">_______________________________________________<br>
LLVM Developers mailing list<br>
</span><a moz-do-not-send="true"
href="mailto:llvm-dev@lists.llvm.org"><span
style="font-size:9.0pt;font-family:"Helvetica",sans-serif;color:#954F72">llvm-dev@lists.llvm.org</span></a><span
style="font-size:9.0pt;font-family:"Helvetica",sans-serif"><br>
</span><a moz-do-not-send="true"
href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev"><span
style="font-size:9.0pt;font-family:"Helvetica",sans-serif;color:#954F72">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</span></a><o:p></o:p></p>
</div>
</blockquote>
</div>
<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
<br>
<br>
<o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>LLVM Developers mailing list<o:p></o:p></pre>
<pre><a moz-do-not-send="true" href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><o:p></o:p></pre>
<pre><a moz-do-not-send="true" href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><o:p></o:p></pre>
</blockquote>
<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
<pre>-- <o:p></o:p></pre>
<pre>Hal Finkel<o:p></o:p></pre>
<pre>Lead, Compiler Technology and Programming Languages<o:p></o:p></pre>
<pre>Leadership Computing Facility<o:p></o:p></pre>
<pre>Argonne National Laboratory<o:p></o:p></pre>
<p>---------------------------------------------------------------------<br>
Intel Israel (74) Limited<o:p></o:p></p>
<p>This e-mail and any attachments may contain confidential
material for<br>
the sole use of the intended recipient(s). Any review or
distribution<br>
by others is strictly prohibited. If you are not the intended<br>
recipient, please contact the sender and delete all copies.<o:p></o:p></p>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory</pre>
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