Displaying 20 results from an estimated 200 matches similar to: "[lld] avoid emitting PLT entries for ifuncs"
2018 Aug 23
2
[lld] avoid emitting PLT entries for ifuncs
In the context of support not only IFunc but DTrace, what kind of features
do you want to add to lld, if you have a chance to implement it in the
linker instead of a post-processing tool? I wonder if we can solve both of
your problems.
On Thu, Aug 23, 2018 at 1:33 AM Mark Johnston <markj at freebsd.org> wrote:
> On Wed, Aug 22, 2018 at 10:11:00AM -0400, Ed Maste wrote:
> > On 22
2020 Aug 21
3
[RFC][LLVM] New Constant type for representing function PLT entries
> -----Original Message-----
> From: llvm-dev <llvm-dev-bounces at lists.llvm.org> On Behalf Of Fangrui
> Song via llvm-dev
> Sent: Thursday, August 20, 2020 10:18 PM
> To: Leonard Chan <leonardchan at google.com>
> Cc: llvm-dev <llvm-dev at lists.llvm.org>
> Subject: [EXT] Re: [llvm-dev] [RFC][LLVM] New Constant type for
> representing function PLT
2020 Aug 21
5
[RFC][LLVM] New Constant type for representing function PLT entries
I do have concerns about the amount of object level modeling that we want
to do in the IR though. While it isn't the highest level IR we've managed
to mostly avoid these kinds of features/complications in the past. I'm
definitely interested in hearing some alternate implementations here and
there rather than a full set of constants for relocations. Keeping the IR
abstract enough over
2015 Dec 18
2
RFC: __attribute__((ifunc("resolver")) representation in LLVM IR
Hi Everyone,
I would like to implement GCC ifunc attribute support in Clang and LLVM. At
the moment Clang ignores the attribute with a warning. On LLVM IR level
there is no support for ifunc. But there is some support for ELF symbol
type `@gnu_indirect_function` in ELF reader/writer/target asm parser. This
RFC is looking for thoughts and suggestions about representation of ifunc
in LLVM IR.
2015 Dec 21
2
RFC: __attribute__((ifunc("resolver")) representation in LLVM IR
I would like to support __attribute__((target)) later so ifunc won't be opaque
for compiler generated dispatchers.
Thank you all for the feedback!
On Sat, Dec 19, 2015 at 8:49 AM, Eric Christopher via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> I think 2 is the only reasonable answer. And to answer Reid's comment:
> yes, it might be nice if we could look through it for
2015 Dec 23
2
RFC: __attribute__((ifunc("resolver")) representation in LLVM IR
If changing nothing else I would probably go with another list since
that is what is done for functions/variables/aliases.
Having said that, more than once I wished we had an easy way to
iterate all GlobalValues or all GrobalObjects. Any thoughts on the
tradeoff having a single list with pointer to the start of each sub
list? Something like
Func1 <-> Func2 <-> Var1 <-> Var2
2015 Dec 19
2
RFC: __attribute__((ifunc("resolver")) representation in LLVM IR
Are you going to have to teach LLVM how to look through ifuncs, or is it OK
if they are totally opaque?
For example, with __attribute__((target)), you might have one
target-specialized function call another. Is it important that we be able
to optimize away the dynamic dispatch there or not?
Either way, I think a new IR construct is the way to go.
On Fri, Dec 18, 2015 at 11:44 AM, Rafael
2020 Aug 10
3
resolve the name of an ifunc resolver function
Hi,
I just spent 4 hours trying to find a way to get the name of the
resolver function of a ifunc definition ... :-(
and with all that time I didnt event get far:
for (GlobalIFunc &IF : M.ifuncs()) {
StringRef ifunc_name = IF.getName();
Constant *r = IF.getResolver();
But how do I get to the (Function*) or function name of the resolver
from there? I tried everything with the Constant
2009 Jul 04
3
newby question
Hi,
I work with bio-conductor, but this is probably a basic R question.
I want to emulate the GOBPOFFSPRING$"GO:0008150" command:
> allBP <- GOBPOFFSPRING$"GO:0008150"
> class(allBP)
[1] "character"
> length(allBP)
[1] 16066
>
I want to create a function so that I can execute the command by passing as a parameter the portion in quotes in the above
2020 Sep 07
3
[IR] Modelling of GlobalIFunc
I was working on https://reviews.llvm.org/D81911 to try and fix
https://bugs.llvm.org/show_bug.cgi?id=46340 . Through the review
process we happened upon a design limitation or perhaps a potential
mis-modelling of GlobalIFunc in the IR object hierarchy, which leads
to some problems in LTO flows.
To summarize, as it currently stands (and in the hopes of faithfully
representing the conclusions of
2020 Sep 10
2
[IR] Modelling of GlobalIFunc
> * Calling getBaseObject() on a GlobalIFunc returns its resolver function.
I still don't understand how it can happen looking to the code (
https://github.com/llvm/llvm-project/blob/master/llvm/lib/IR/Globals.cpp#L430).
I believe it should return nullptr (the same as if you call it from
GlobalAlias that refers to GlobalIFunc).
I don't have a strong opinion here because deriving
2007 Jul 24
1
Passing equations as arguments
Friends,
I'm trying to pass an equation as an argument to a function. The idea is as follows. Let us say i write an independent function
Ideal Situation:
ifunc <- function(x)
{
return((x*x)-2)
}
mainfunc <- function(a,b)
{
evala <- ifunc(a)
evalb <- ifunc(b)
if (evala>evalb){return(evala)}
else
return(evalb)
}
Now I want to try and write this entire program in a single
2014 May 23
2
[LLVMdev] Changing the design of GlobalAliases to represent what is actually possible in object files.
On Fri, May 23, 2014 at 3:06 PM, Rafael Avila de Espindola
<rafael.espindola at gmail.com> wrote:
>
>
> Sent from my iPhone
>
>> On May 23, 2014, at 17:51, Eric Christopher <echristo at gmail.com> wrote:
>>
>> I'm not there yet, but at some point I'm going to need the notion of a
>> global callable function like symbol that's resolved at
2018 Aug 22
2
[lld] avoid emitting PLT entries for ifuncs
On 22 August 2018 at 04:27, Rui Ueyama via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>
> However, if you pass the -emit-relocs option to the linker, lld keeps all
> relocations that have already been resolved in an output executable. By
> analyzing a relocation table in a resulting executable, you could find all
> locations where the ifunc PLT is called. Then, you can
2013 Oct 07
2
[LLVMdev] [lld][failing test] the reason of ifunc.test failing
Hi,
It looks like the the ELFPassFile doesnot get an ordinal value assigned,
as its added in a pass.
Is there a way to assign a file ordinal for the files added by Passes ?
Till that time, I am going to XFAIL the ifunc test.
More tests should fail, and am not sure why they are not failing.
Thanks
Shankar Easwaran
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted
2014 May 23
3
[LLVMdev] Changing the design of GlobalAliases to represent what is actually possible in object files.
I'm not there yet, but at some point I'm going to need the notion of a
global callable function like symbol that's resolved at runtime. I've
not given it much thought but I may need a new callable entity here
(this is for the gnu ifunc stuff).
Don't even know if this fits into the discussion, but since we were
talking about weird symbols...
-eric
On Fri, May 23, 2014 at 1:26
2016 May 26
1
Potential ambiguity in the grammar of LLVM IR assembly
Hello Tim,
Thank you for getting back to me.
The language grammar as defined by the LLVM Language Reference Manual
[1] does not include the details of the LLVM IR parser reference
implementation.
The following extract from "lib/AsmParser/LLParser.cpp" illustrates that
unnamed globals are allowed [2].
> /// ParseUnnamedGlobal:
> /// OptionalVisibility (ALIAS | IFUNC) ...
2017 Apr 04
4
RFC: Adding a string table to the bitcode format
On Mon, Apr 3, 2017 at 8:13 PM, Mehdi Amini <mehdi.amini at apple.com> wrote:
>
> On Apr 3, 2017, at 7:08 PM, Peter Collingbourne <peter at pcc.me.uk> wrote:
>
> Hi,
>
> As part of PR27551 I want to add a string table to the bitcode format to
> allow global value and comdat names to be shared with the proposed symbol
> table (and, as side effects, allow comdat
2013 Oct 07
0
[LLVMdev] [lld][failing test] the reason of ifunc.test failing
In addition I think the LayoutPass std::stable_sort be replaced with
std::sort as total ordering is guaranteed as each File would get an
ordinal and each atom would get an ordinal too, after the below problem
is fixed.
Thanks
Shankar Easwaran
On 10/6/2013 10:54 PM, Shankar Easwaran wrote:
> Hi,
>
> It looks like the the ELFPassFile doesnot get an ordinal value
> assigned, as its
2013 Oct 07
2
[LLVMdev] [lld][failing test] the reason of ifunc.test failing
Ping ?
Do you think that we need to have an API in LinkingContext to return the
next ordinal available, so that files created by passes can be assigned
ordinals ?
Thanks
Shankar Easwaran
On 10/6/2013 11:07 PM, Shankar Easwaran wrote:
> In addition I think the LayoutPass std::stable_sort be replaced with
> std::sort as total ordering is guaranteed as each File would get an
>