Displaying 20 results from an estimated 7000 matches similar to: "[LLVMdev] loop vectorizer: JIT + AVX segfaults"
2013 Nov 11
0
[LLVMdev] loop vectorizer: JIT + AVX segfaults
Do you have a stack trace of the segfault?
We have two different code emitters for X86 in LLVM. The one used by the
normal compiler and MCJIT and the other used by the legacy JIT. All of the
test cases for AVX support go through the first one so it gets the most
attention. We try to keep the legacy JIT in sync with it, but have a
history of failing at that. The stack trace of the segfault may
2013 Nov 11
2
[LLVMdev] loop vectorizer: JIT + AVX segfaults
It's not much.
(gdb) bt
#0 0x00007ffff7f6506b in ?? ()
#1 0x000000000045d01a in main () at main.cc:165
Line 165 is the call to the function that was compiled by the JIT'er.
Meaning that JIT'ing the function went well, but the code or the pointer
are somehow corrupt.
There is no particular reason why I am working with the legacy
interface. Would you recommend to use the MCJIT
2013 Nov 11
0
[LLVMdev] loop vectorizer: JIT + AVX segfaults
I changed the code to use the MCJIT engine. As Josh suspected
it's the same issue: The program runs fine on SSE based machines,
but SEGFAULTs on a CPU with AVX extensions.
I attach the repro case.
Should I file a bug report? P.S. On bugzilla there is the component
'new-bugs'. Should all new bugs be filed there?
Frank
On 11/11/13 08:45, Josh Klontz wrote:
> For what it's
2013 Nov 10
0
[LLVMdev] loop vectorizer erroneously finds 256 bit vectors
Hi Renato,
you are right! There is 'avx' support:
fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36
clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb
rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology
nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est
tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave
2013 Nov 10
2
[LLVMdev] loop vectorizer erroneously finds 256 bit vectors
Hi Frank,
I'm not an Intel expert, but it seems that your Xeon E5 supports AVX, which
does have 256-bit vectors. The other two only supports SSE instructions,
which are only 128-bit long.
cheers,
--renato
On 10 November 2013 06:05, Frank Winter <fwinter at jlab.org> wrote:
> I looked more into this. For the previously sent IR the vector width of
> 256 bit is found mistakenly
2000 Mar 31
1
R: one bananna aov() question
Hello world,
I'm trying to do an
anova on data in data.set, dependent variable is a column
named "dep.var", grouping variable is in a column called "indep.var", and
is.factor(indep.var) is TRUE...
why can't I just do aov(dep.var ~ indep.var, data = data.set)?
What have I done to deserve this?! What gives? Am I missing something
totlly obvious?
R-base-1.0.0-1,
2012 Jun 27
1
Strucchange: Breakpoint slow
Hi to all,
I am trying to run breakpoints() on a fairly large sample (>10.000
observations). The process is very slow, any idea on how to speed this up? I
have tried the hpc="foreach" parameter, but this didn't work at all when I
tried to run it on a smaller sample.
breakpoints(x ~ x.l1 + x.l2 + X.l3 + x.l4 + x.l5 + x.l6 + x.l7 + x.l8 + y.l1
+ y.l2 + y.l3 + y.l4 + y.l5 + y.l6
2013 Nov 10
0
[LLVMdev] loop vectorizer erroneously finds 256 bit vectors
I looked more into this. For the previously sent IR the vector width of
256 bit is found mistakenly (and reproducibly) on this hardware:
model name : Intel(R) Xeon(R) CPU E5-2650 0 @ 2.00GHz
For the same IR the loop vectorizer finds the correct vector width (128
bit) on:
model name : Intel(R) Xeon(R) CPU E5630 @ 2.53GHz
model name : Intel(R) Core(TM) i7 CPU M 640 @
2013 Nov 11
2
[LLVMdev] loop vectorizer: JIT + AVX segfaults
For what it's worth, I'm also experiencing this same issue. If there is
interest I can provide some very simple reproducible test cases, but I was
planning on moving to MCJIT this week anyway.
--
View this message in context: http://llvm.1065342.n5.nabble.com/loop-vectorizer-JIT-AVX-segfaults-tp63089p63115.html
Sent from the LLVM - Dev mailing list archive at Nabble.com.
2013 Nov 10
3
[LLVMdev] loop vectorizer erroneously finds 256 bit vectors
The loop vectorizer is doing an amazing job so far. Most of the time.
I just came across one function which led to unexpected behavior:
On this function the loop vectorizer finds a 256 bit vector as the
wides vector type for the x86-64 architecture. (!)
This is strange, as it was always finding the correct size of 128 bit
as the widest type. I isolated the IR of the function to check if this
is
2007 Apr 13
0
How consistent is predict() syntax?
I have a situation where lagged values of a time-series are used to
predict future values. I have packed together the time-series and the
lagged values into a data frame:
> str(D)
'data.frame': 191 obs. of 13 variables:
$ y : num -0.21 -2.28 -2.71 2.26 -1.11 1.71 2.63 -0.45 -0.11 4.79
...
$ y.l1 : num NA -0.21 -2.28 -2.71 2.26 -1.11 1.71 2.63 -0.45 -0.11
...
$ y.l2 : num
2014 Dec 12
2
[Bug 991] New: Exactly after 24h of uptime system hungs
https://bugzilla.netfilter.org/show_bug.cgi?id=991
Bug ID: 991
Summary: Exactly after 24h of uptime system hungs
Product: netfilter/iptables
Version: unspecified
Hardware: sparc64
OS: Debian GNU/Linux
Status: NEW
Severity: blocker
Priority: P5
Component: ip_tables (kernel)
2013 Nov 06
0
[LLVMdev] loop vectorizer: Unexpected extract/insertelement
Yes, you need the latest ToT version of llvm or you run
-loop-vectorize -earlycse -instcombine -simplifycfg
The bitcast essentially is a noop to satisfy the type system.
This is how your example looks like for me:
vector.body: ; preds = %vector.body, %vector.ph
%index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
%.lhs = shl i64 %6, 2
2013 Nov 06
0
[LLVMdev] loop vectorizer: Unexpected extract/insertelement
The loop vectorizer relies on cleanup passes to be run after it:
from Transforms/IPO/PassManagerBuilder.cpp:
// Add the various vectorization passes and relevant cleanup passes for
// them since we are no longer in the middle of the main scalar pipeline.
MPM.add(createLoopVectorizePass(DisableUnrollLoops));
MPM.add(createInstructionCombiningPass());
2013 Nov 06
2
[LLVMdev] loop vectorizer: Unexpected extract/insertelement
The instcombine pass cleans up a lot.
Any idea why there are still shufflevector, insertelement, *and* bitcast
(!!) etc. instructions left? The original loop is so clean, a textbook
example I'd say. There is no need to shuffle anything.At least I don't
see it.
Frank
vector.ph: ; preds = %L5
%broadcast.splatinsert1 = insertelement <4 x
2013 Nov 06
2
[LLVMdev] loop vectorizer: Unexpected extract/insertelement
The following IR implements the following nested loop:
for (int i = start ; i < end ; ++i )
for (int p = 0 ; p < 4 ; ++p )
a[i*4+p] = b[i*4+p] + c[i*4+p];
define void @main(i64 %arg0, i64 %arg1, i1 %arg2, i64 %arg3, float*
noalias %arg4, float* noalias %arg5, float* noalias %arg6) {
entrypoint:
br i1 %arg2, label %L0, label %L1
L0:
2013 Aug 22
2
New routine: FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_16
libFLAC have three SSE-accelerated functions FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_N (N = 4, 8, 12). They require lpc_order less than N.
The best compression preset (flac -8) uses lpc_order up to 12; it means that during encoding FLAC also uses unaccelerated C function.
I'm not very familiar with asm so I took FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_12, changed it and
2018 Apr 10
1
How to get the case value from Machine Instruction
Thanks for your help.
Is there possible I can get the realily case value form the MI?
For the case in https://bugs.llvm.org/show_bug.cgi?id=34902.
as follows.
#############################
* GCC v7.1 generated assembly
#############################
** Options: -Os -marm -march=armv7-a
foo:
@ args = 0, pretend = 0, frame = 0
@ frame_needed = 0, uses_anonymous_args = 0
sub
2006 Jan 30
0
Samba 3.0.21a (64 Bit) dumps core when trying to join domain on Solaris 9
Hi,
I recently tried to get Samba 3.0.21a running on Solaris 9 several
times, using different build environments. The compilers in use where
Sun Forte Version 11 and gcc 3.4.2. The binaries where compiled for 64
bit, using CFLAGS="-m64" for gcc for example. I just used
configure --prefix=<path>
The core file analysis of the latest build shows that strlen() is called:
# mdb core
2018 Mar 09
0
NHW Project - lower quality settings
Hello,
I have re-tested -l4 high compression setting and it's clear that it lacks
of precision on degraded, rather blurred images. So I don't know if it is a
good idea to base the other lower quality settings (-l5,-l6,...) on -l4
setting.I have tested the NHW codec against x265, x264, Daala, WebP,
Rududu, DLI and it's clear that at high compression these very good codecs
have more