Hi Jim/Evan, We had this discussion last year, and I think it's time we revisited this issue again. Many of us (Linaro, ARM, CodeAurora) have been using the ARM integrated assembler for compiling large projects, the test-suite, buildbots, and there seem to be no bug pending on them, with the obscure cases being a few unsupported directives, some of which are already being implemented, while the rest is reported but not crucial to fixing it before IAS is default. The true counter-example is the kernel, which still has many issues, but I'm not expecting it to support everything in the kernel as of now. That's why the LLVMLinux guys still use the -no-integrated-as option by default for both x86 and ARM. Also, their plans is to zero the patches to the kernel *before* making sure the IAS works unpatched, which could take a long time. In a nutshell, it seems to be our consensus that the integrated assembly can now be turned on by default on ARM, and we should add -no-integrated-as for the cases where it fails (like the kernel). Do you agree with this consensus, and does it work as expected on Darwin? cheers, --renato
On Tue, Dec 10, 2013 at 02:26:53PM +0000, Renato Golin wrote:> In a nutshell, it seems to be our consensus that the integrated > assembly can now be turned on by default on ARM, and we should add > -no-integrated-as for the cases where it fails (like the kernel).It can't assemble basic PIC code as created by clang -S for ELF platforms. That's IMO a pretty big show stopper. Joerg
> In a nutshell, it seems to be our consensus that the integrated > assembly can now be turned on by default on ARM, and we should add > -no-integrated-as for the cases where it fails (like the kernel).I'm definitely in favour! Tim.
On 10 December 2013 15:00, Joerg Sonnenberger <joerg at britannica.bec.de> wrote:> On Tue, Dec 10, 2013 at 02:26:53PM +0000, Renato Golin wrote: >> In a nutshell, it seems to be our consensus that the integrated >> assembly can now be turned on by default on ARM, and we should add >> -no-integrated-as for the cases where it fails (like the kernel). > > It can't assemble basic PIC code as created by clang -S for ELF > platforms.Is there a PR for this? We should link it to one of the issues that exist for integrated-as.> That's IMO a pretty big show stopper.I disagree. It's nice and probably should be a priority to fix, but it's not the standard use-situation for Clang. Cheers. Tim.
I don't have any real say in this. It should be decided by folks who are working on ARM / ELF such as yourself. If you collectively feel it's ready to make the switch then I don't have any objections. Evan On Dec 10, 2013, at 6:26 AM, Renato Golin <renato.golin at linaro.org> wrote:> Hi Jim/Evan, > > We had this discussion last year, and I think it's time we revisited > this issue again. > > Many of us (Linaro, ARM, CodeAurora) have been using the ARM > integrated assembler for compiling large projects, the test-suite, > buildbots, and there seem to be no bug pending on them, with the > obscure cases being a few unsupported directives, some of which are > already being implemented, while the rest is reported but not crucial > to fixing it before IAS is default. > > The true counter-example is the kernel, which still has many issues, > but I'm not expecting it to support everything in the kernel as of > now. That's why the LLVMLinux guys still use the -no-integrated-as > option by default for both x86 and ARM. Also, their plans is to zero > the patches to the kernel *before* making sure the IAS works > unpatched, which could take a long time. > > In a nutshell, it seems to be our consensus that the integrated > assembly can now be turned on by default on ARM, and we should add > -no-integrated-as for the cases where it fails (like the kernel). > > Do you agree with this consensus, and does it work as expected on Darwin? > > cheers, > --renato
On 10 December 2013 21:48, Evan Cheng <evan.cheng at apple.com> wrote:> I don't have any real say in this. It should be decided by folks who are working on ARM / ELF such as yourself. If you collectively feel it's ready to make the switch then I don't have any objections.Thanks Evan! I wanted to make sure there were no issues on Darwin, as I really don't get to play much in that area. I think we have enough interest to change and enough volume of bug fixes and new features in the IAS to make the move now. I'll send a patch. cheers, --renato