search for: subtleties

Displaying 20 results from an estimated 321 matches for "subtleties".

2014 Oct 19
14
[LLVMdev] RFC: Are we ready to completely move away from the optionality of a DataLayout?
I've just wasted a day chasing my tail because of subtleties introduced to handle the optionality of the DataLayout. I would like to never do this again. =] We now have this attached to the Module with just a flimsy faked-up pass to keep APIs consistent. So, is there any problem with beginning down the path of: 1) Synthesizing a "default" boring...
2011 Jun 24
9
[PATCH] xen_disk: cope with missing xenstore "params" node
From: Stefano Stabellini <stefano.stabellini@eu.citrix.com> When disk is a cdrom and the drive is empty the "params" node in xenstore might be missing completely: cope with it instead of segfaulting. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> --- hw/xen_disk.c | 16 +++++++++++----- 1 files changed, 11 insertions(+), 5 deletions(-) diff --git
2006 Mar 21
1
build R on windows
Hi, I'm not sure if this question has been answered before, but when I execute command "Rcmd INSTALL --build nws" to build an R package on Windows, the build process got stucked on the save image step. Here is the snapshot of the build process, --- Making package nws ---- adding build stamp to DESCRIPTION installing NAMESPACE file and metadata installing R files
2018 Oct 06
2
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
On Thu, Oct 04, 2018 at 03:15:32PM -0700, Andy Lutomirski wrote: > For better or for worse, I'm trying to understand this code. So far, > I've come up with this patch: > > https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git/commit/?h=x86/vdso-tglx&id=14fd71e12b1c4492a06f368f75041f263e6862bf > > Is it correct, or am I missing some subtlety? The master
2018 Oct 06
2
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
On Thu, Oct 04, 2018 at 03:15:32PM -0700, Andy Lutomirski wrote: > For better or for worse, I'm trying to understand this code. So far, > I've come up with this patch: > > https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git/commit/?h=x86/vdso-tglx&id=14fd71e12b1c4492a06f368f75041f263e6862bf > > Is it correct, or am I missing some subtlety? The master
2014 Mar 12
3
[LLVMdev] [ARM] [PIC] optimizing the loading of hidden global variable
Hi, When I’m compiling a code with –fvisibility=hidden –fPIC for ARM, I find that LLVM generates less optimized code than GCC. For example: test.cpp: void init(void *); int g0[100]; int g1[100]; int g2[100]; void foo() { init(&g0); init(&g1); init(&g2); } Clang will emit 1 GOT entry for each GV and 2 instructions to get the address: ldr
2016 Nov 29
2
RFC: Constructing StringRefs at compile time
char buffer[100]; And it also allows LIT(buffer) to compile, whereas the UDL doesn't. On Tue, Nov 29, 2016 at 9:54 AM Mehdi Amini <mehdi.amini at apple.com> wrote: > > > On Nov 29, 2016, at 9:52 AM, Malcolm Parsons <malcolm.parsons at gmail.com> > wrote: > > > > On 29 November 2016 at 17:38, Zachary Turner <zturner at google.com> wrote: > >>
2017 Jun 13
3
RFC: Dynamic dominators
...all the work of the separate passes. The main cost is the DFS walk, and you can't do an undirected DFS that will work here. I believe related things have even been proven to show the brokenness of various algorithms. See https://hal.inria.fr/hal-00761505 section 4.1 Given the difficulties and subtleties here, I would consider any such approach that tried to share work between the passes as "fraught with peril" -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20170613/7e634774/attachment.html>
2009 Sep 09
4
usdt probes vs pid$target
I added a couple of static probes to Firefox to measure actual work done. I could have used a pid$target probe with a function name but work is done within an if statement, which is where I placed the static probes. I''m wondering about my use, though. Is the following significantly more efficient than pid$target::FunName:entry and return? I heard somewhere that $target does not
2014 Aug 20
2
[LLVMdev] llvm::Triple support for haswell-enabled x86_64
...;x86_64-...' and an '-march' flag. > > It just seems like a reinvention of i386, i486, and iN86, probably for all of the same reasons. If you can encode all the important things in the triple, you can have different library directories for distributions, etc. There’s a few more subtleties, but that’s a reasonable analogy. While the sub-arch is related to a -march= setting, it is very definitely not the same thing. It’s not even just the sub-arch. Consider, for example, that “thumb” and “arm” have separate top-level triple values. Yes, this whole system of how the arch and sub arch...
2015 Oct 20
2
[compiler-rt] Undefined negation in float emulation functions
Hi, I recently came across the following in __floatsidf in compiler-rt: __floatsidf(int a) { ... if (a < 0) { ... a = -a; In the case where a == INT_MIN, is this negation not undefined behaviour? AIUI this function is used for software emulation on targets that have no hardware floating point support. Perhaps there is an in-built assumption
2018 Oct 04
3
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
> On Oct 4, 2018, at 12:31 PM, Peter Zijlstra <peterz at infradead.org> wrote: > > On Thu, Oct 04, 2018 at 07:00:45AM -0700, Andy Lutomirski wrote: >>> On Oct 4, 2018, at 1:11 AM, Peter Zijlstra <peterz at infradead.org> wrote: >>> >>>> On Thu, Oct 04, 2018 at 09:54:45AM +0200, Vitaly Kuznetsov wrote: >>>> I was hoping to hear this
2018 Oct 04
3
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
> On Oct 4, 2018, at 12:31 PM, Peter Zijlstra <peterz at infradead.org> wrote: > > On Thu, Oct 04, 2018 at 07:00:45AM -0700, Andy Lutomirski wrote: >>> On Oct 4, 2018, at 1:11 AM, Peter Zijlstra <peterz at infradead.org> wrote: >>> >>>> On Thu, Oct 04, 2018 at 09:54:45AM +0200, Vitaly Kuznetsov wrote: >>>> I was hoping to hear this
2018 Oct 08
2
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
On Sat, Oct 06, 2018 at 03:28:05PM -0700, Andy Lutomirski wrote: > On Sat, Oct 6, 2018 at 1:29 PM Marcelo Tosatti <mtosatti at redhat.com> wrote: > > > > On Thu, Oct 04, 2018 at 03:15:32PM -0700, Andy Lutomirski wrote: > > > For better or for worse, I'm trying to understand this code. So far, > > > I've come up with this patch: > > > >
2018 Oct 08
2
[patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support
On Sat, Oct 06, 2018 at 03:28:05PM -0700, Andy Lutomirski wrote: > On Sat, Oct 6, 2018 at 1:29 PM Marcelo Tosatti <mtosatti at redhat.com> wrote: > > > > On Thu, Oct 04, 2018 at 03:15:32PM -0700, Andy Lutomirski wrote: > > > For better or for worse, I'm trying to understand this code. So far, > > > I've come up with this patch: > > > >
2015 Aug 31
2
SMBx differences re Win10 in Samba4 NT4 DC
Given an existing NT4 Samba 4 DC, a recently upgraded Win10 machine can no longer access NETLOGON to authenticate to the network. This lead to the research revealing that my Samba4 PDC SMB.CONF must be changed to limit MAX PROTOCOL = NT1 to avoid negotiating a version of SMB2 from Win10 that Samba4 can't resolve. Doing this broke authentication via other resources that no longer support NT1,
2014 Sep 05
2
[LLVMdev] '___ltsf2' could not be resolved - iOS/ARM cross compile
Hi there, I’m building llvm for my iOS devices, and all seems to work well, until I try to execute the results: LLVM ERROR: Program used external function '___ltsf2' which could not be resolved! This appears to be part of compiler-rt which as far as I can see should be built / linked automatically when installed correctly? Am I missing something obvious? Thanks, .m
2017 Jan 11
2
16-bit bytes support
Hi. I'm working on a backend for the [DCPU16](https://github.com/techcompliant/TC-Specs/blob/master/CPU/DCPU.md), a fictional CPU. The main subtlety is that the bytes are 16 bits instead of 8. There is already a [working backend](https://github.com/krasin/llvm-dcpu16), but it does a lot of source modification to support 16 bit words. I try to update it to latest llvm, but it obviously
2019 Jul 22
1
Re: [libnbd] More thoughts on callbacks and more
This has an annoying subtlety around the fact that we can pass a single user_data and multiple closures in one function call. The LIBNBD_CALLBACK_FREE function would be called several times with the same user_data in this case, which means the callback must do some kind of reference counting before the user_data can be freed. I propose that we split up Closure so it describes a single closure,
2009 Jun 19
1
Fancy Ticks in Plots
Dear All, I am pretty satisfied with R for my plotting, but there are a few subtleties which I cannot figure out. Consider figure 1 in the paper at the link below http://cxnets.googlepages.com/univ_citations.pdf Can I have the same kind of ticks in an R-generated figure (that is to say: ticks along the 4 axis, and in a log-log plot I'd like a larger tick for any power of 10)....