Displaying 20 results from an estimated 20000 matches similar to: "[LLVMdev] How to set default target flags?"
2015 May 31
2
[LLVMdev] how to add some default target flags?
Hello,
I've built LLVM natively on a fpu-less (soft-float) mips32 target, and
built mesa to use it.
However llvm apparently cannot determine what machine it's running on and builds
code for a generic mips target with fpu.
Is there a way to have llc/llvm always use "-march=mipsle -mcpu=mips32
-mattr=+soft-float" as a default command line, something similar to
gcc's
2017 Sep 26
1
Difference between -mattr=+soft-float and -float-abi=soft
Hi Tim,
Ohh, I completely forgot to attach the source. Running this with:
$ llc -O2 -mcpu=generic HeapStackCheck.ll -mattr=+soft-float -o HeapStackCheck.s
results in
0 llc 0x000000010fea65e6 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 37
1 llc 0x000000010fea5b3a llvm::sys::RunSignalHandlers() + 83
2 llc
2012 Aug 02
1
[LLVMdev] Question about arm thumb2 code generation
Thanks andrew for the answer.
I would like to generate code for Cortex-A9 that don't use neon for fp computation but vfpv3 -d16. I've tried some combination of -mattr=+neon,-neonfp,+vfp3,+d16 but couldn't get ".fpu vfpv3-d16" directive generated in assembly file. Do you know how to make it happen ?
Best Regards
Seb
From: Andrew Trick [mailto:atrick at apple.com]
Sent:
2018 Sep 25
2
[RFC] New Clang target selection options for ARM/AArch64
Hi Eli, Renato,
Thanks for your feedback, there's a lot more to some of these things than I knew. I've addressed your points below.
The overall summary is:
- Start with converting the TargetParser to tableGen, with no user facing changes
- Add warnings based on that, behind -Wall. Starting with command lines, since directives have
larger implications that need investigation
Thanks,
2012 Jul 28
0
[LLVMdev] Question about arm thumb2 code generation
On Jul 27, 2012, at 9:04 AM, Sebastien DELDON-GNB <sebastien.deldon at st.com> wrote:
> Hi all,
>
> Does llc –march=thumb –mcpu=cortex-a9 enable generation of thumb2 code for armv7 ?
That's how I usually do it. Somewhere in the target description we associate a9 with -mattr=+thumb2.
There are plenty of other ways to get the same result, and it's all very confusing and
2006 Apr 19
2
[LLVMdev] floating point exception and SSE2 instructions
On Thu, 20 Apr 2006, Simon Burton wrote:
>>> From what I remember, this is a bug in debian libc:
>> some floating point flags are set incorrectly causing SIGFPE.
>> Can't find the bug report ATM.
>
> Oh, it just showed up on numpy-discussion:
> http://sources.redhat.com/bugzilla/show_bug.cgi?id=10
>
> """
> #include <fenv.h>
> void
2019 Apr 10
2
[RFC] New Clang target selection options for ARM/AArch64
Hi Manoj,
Not too late at all, we have not got to that point of the work yet.
Are there examples of this kind of build setup that are available publicly? I think I understand the problem but it'd help to see one in action. To see if there are any other Arm extensions that are already being added like this and whether those systems support GCC and how.
Thanks,
David Spickett.
2017 Sep 26
0
Difference between -mattr=+soft-float and -float-abi=soft
Hi Moritz,
On 26 September 2017 at 09:09, Moritz Angermann via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> I’ve run into a case where `llc -mattr=+soft-float` for
> "armv7-unknown-linux-androideabi” segfaults, while
> `llc -float-abi=soft` does not. Similarly if the
> "target-features"="+soft-float” metadata is embedded,
> llc segfaults.
The float-abi
2006 Apr 19
0
[LLVMdev] floating point exception and SSE2 instructions
On Wed, 19 Apr 2006 18:21:32 -0500 (CDT)
Chris Lattner <sabre at nondot.org> wrote:
>
>
> I don't see what this has to do with anything, but...
Me neither.
>
> > Is there a way I can disable SSE instruction generation in LLVM ?
>
> Yes. Pass -mattr=-sse1,-sse2,-sse3 to lli or llc.
Right, that fixed it.
BTW:
from the --help:
2012 Dec 20
1
[LLVMdev] vmlx forwarding an cortex A9 question
Hi all,
On following code when I use llc targeting ARM Cortex-A9 as follows, if vmlx-forwarding is turned off then 'vmla' instructions are generated. It seems that -mcpu=cortex-a9 enables it by default and thus less 'vmla' instructions are generated. On this specific example it doesn't make any difference in term of performance, but on a more complex example disabling
2019 Apr 16
2
[RFC] New Clang target selection options for ARM/AArch64
Hi Manoj,
I tried a few other options myself:
* function 'target' attribute - the list of extensions this supports isn't complete and it doesn't enable the ACLE macros needed for intrinsics
* manually defining ACLE macros - this allows intrinsics and is additive but assumes that you're not relying on codegen to emit instructions. I don't think it helps the bug linked
2018 Sep 21
5
[RFC] New Clang target selection options for ARM/AArch64
Hi,
Below is a document detailing changes we'd like to make to Clang/LLVM to improve the usability of the target options for ARM and AArch64.
To keep things simple the proposed changes are listed at the start and you can find the supporting examples at the end of the document.
I look forward to your feedback.
Thanks,
David Spickett.
RFC New Clang target feature selection options for
2013 Jan 31
0
[LLVMdev] Getting command line options to affect subtarget features
On Thu, 2013-01-31 at 10:17 -0600, Bill Schmidt wrote:
>
> On Thu, 2013-01-31 at 09:42 -0600, Hal Finkel wrote:
> > ----- Original Message -----
> > > From: "Bill Schmidt" <wschmidt at linux.vnet.ibm.com>
> > > To: llvmdev at cs.uiuc.edu
> > > Sent: Thursday, January 31, 2013 9:26:15 AM
> > > Subject: [LLVMdev] Getting command line
2012 Nov 08
2
[LLVMdev] fmac generation for cortex-a9
Hi Anitha,
Thanks for your answer but -mcpu=cortex-a9 -mattr=+vfp4 doesn' t enable fused mac generation for me.
I would like just to understand why -mtriple=armv7-eabi enables it while -mcpu=cortex-a9 seems to disable it ?
Seb
> -----Original Message-----
> From: Anitha Boyapati [mailto:anitha.boyapati at gmail.com]
> Sent: Thursday, November 08, 2012 10:22 AM
> To: Sebastien
2013 Jun 24
1
[LLVMdev] DebugInfo: Missing non-trivially-copyable parameters in SelectionDAG
This is a bit premature to be considered a code review, but given how
unfamiliar I am with SelectionDAG (& that I'm seeing somewhat more
'interesting' results compared to my change to FastISel) I wanted to
get a bit of feedback to see if I was on the right track or had missed
any obvious cases.
I've attached my patch in progress (including a modification to the
existing test
2013 Jan 31
0
[LLVMdev] Getting command line options to affect subtarget features
----- Original Message -----
> From: "Bill Schmidt" <wschmidt at linux.vnet.ibm.com>
> To: llvmdev at cs.uiuc.edu
> Sent: Thursday, January 31, 2013 9:26:15 AM
> Subject: [LLVMdev] Getting command line options to affect subtarget features
>
> The problem I'm trying to solve: Invoking clang on PowerPC with
> -fno-altivec has no effect.
>
> From what
2012 Nov 09
0
[LLVMdev] fmac generation for cortex-a9
AFAIK A9 doesn't have VFPv4 or AdvSIMDv2, so it doesn't have VFMA. I don't
know what LLVM does, but it shouldn't emit VFMA when you target A9. VMLA
isn't a fused multiply-add, it's a multiply followed by an add and has
different latency as well as precision.
On Thu, Nov 8, 2012 at 4:57 AM, Sebastien DELDON-GNB <
sebastien.deldon at st.com> wrote:
> Hi Anitha,
2013 Jan 31
2
[LLVMdev] Getting command line options to affect subtarget features
The problem I'm trying to solve: Invoking clang on PowerPC with
-fno-altivec has no effect.
>From what I've been able to piece together, PPC.td specifies various
CPUs and the processor features available on each. So for example we
have:
def FeatureAltivec : SubtargetFeature<"altivec","HasAltivec", "true",
2013 Jan 31
0
[LLVMdev] Getting command line options to affect subtarget features
On Thu, 2013-01-31 at 11:29 -0600, Bill Schmidt wrote:
> On Thu, 2013-01-31 at 11:23 -0600, Bill Schmidt wrote:
> > On Thu, 2013-01-31 at 10:17 -0600, Bill Schmidt wrote:
> > >
> > > On Thu, 2013-01-31 at 09:42 -0600, Hal Finkel wrote:
> > > > ----- Original Message -----
> > > > > From: "Bill Schmidt" <wschmidt at
2013 Jan 31
2
[LLVMdev] Getting command line options to affect subtarget features
On Thu, 2013-01-31 at 09:42 -0600, Hal Finkel wrote:
> ----- Original Message -----
> > From: "Bill Schmidt" <wschmidt at linux.vnet.ibm.com>
> > To: llvmdev at cs.uiuc.edu
> > Sent: Thursday, January 31, 2013 9:26:15 AM
> > Subject: [LLVMdev] Getting command line options to affect subtarget features
> >
> > The problem I'm trying to