search for: preserve_most

On Fri, Jul 8, 2016 at 9:47 AM, Lawrence, Peter <c_plawre at qca.qualcomm.com> wrote: > Vivek, > > I am looking into these function attributes in the clang docs > > Preserve_most > > Preserve_all > > They are not available in the 3.6.2 that I am currently using, but I hope > they exist in 3.8 > > > > These should provide enough info to solve my problem, > > at the MC level calls to functions with these attributes > > wi...

...at gmail.com<mailto:vivekvpandya at gmail.com>> wrote: On Fri, Jul 8, 2016 at 9:47 AM, Lawrence, Peter <c_plawre at qca.qualcomm.com<mailto:c_plawre at qca.qualcomm.com>> wrote: Vivek, I am looking into these function attributes in the clang docs Preserve_most Preserve_all They are not available in the 3.6.2 that I am currently using, but I hope they exist in 3.8 These should provide enough info to solve my problem, at the MC level calls to functions with these attributes with be code-gen’ed through different “calling conventions”, and...

...at gmail.com<mailto:vivekvpandya at gmail.com>> wrote: On Fri, Jul 8, 2016 at 9:47 AM, Lawrence, Peter <c_plawre at qca.qualcomm.com<mailto:c_plawre at qca.qualcomm.com>> wrote: Vivek, I am looking into these function attributes in the clang docs Preserve_most Preserve_all They are not available in the 3.6.2 that I am currently using, but I hope they exist in 3.8 These should provide enough info to solve my problem, at the MC level calls to functions with these attributes with be code-gen’ed through different “calling conventions”, and...

...at gmail.com<mailto:vivekvpandya at gmail.com>> wrote: On Fri, Jul 8, 2016 at 9:47 AM, Lawrence, Peter <c_plawre at qca.qualcomm.com<mailto:c_plawre at qca.qualcomm.com>> wrote: Vivek, I am looking into these function attributes in the clang docs Preserve_most Preserve_all They are not available in the 3.6.2 that I am currently using, but I hope they exist in 3.8 These should provide enough info to solve my problem, at the MC level calls to functions with these attributes with be code-gen’ed through different “calling conventions”, and...

Hello Peter, Thanks to pointing out this interesting case. > Vivek, > I have an application where many of the leaf functions are > Hand-coded assembly language, because they use special IO instructions > That only the assembler knows about. These functions typically don't > Use any registers besides the incoming argument registers, IE they don't > Need to

...at gmail.com<mailto:vivekvpandya at gmail.com>> wrote: On Fri, Jul 8, 2016 at 9:47 AM, Lawrence, Peter <c_plawre at qca.qualcomm.com<mailto:c_plawre at qca.qualcomm.com>> wrote: Vivek, I am looking into these function attributes in the clang docs Preserve_most Preserve_all They are not available in the 3.6.2 that I am currently using, but I hope they exist in 3.8 These should provide enough info to solve my problem, at the MC level calls to functions with these attributes with be code-gen’ed through different “calling conventions”, and...

> On Jul 7, 2016, at 9:17 PM, Lawrence, Peter via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > Vivek, > I am looking into these function attributes in the clang docs > Preserve_most > Preserve_all > They are not available in the 3.6.2 that I am currently using, but I hope they exist in 3.8 > > These should provide enough info to solve my problem, > at the MC level calls to functions with these attributes > with be code-gen’ed through differ...

Hello Clang and LLVM Devs, I have been working to add support for an attribute in clang and LLVM that helps user to guide interprocedural register allocation. But the use case I am having is very limited and thus I belieave it is good to have discussion on this before sending a patch. So for IPRA we have a situation where a function is calling a function which is written in assembly and it is

Vivek, I apologize if you took my original email as a request for implementation, I meant to be asking what is already available, I think the answer to that is the ‘preserves_most’ and ‘preserves_all’ attributes, but I will also Use ‘regmask’ if those prove to be too sub-optimal. I am still interested in figuring out the necessary and sufficient conditions For LLC to do optimal IPRA

...ule. One such case > is when functions written in pure assembly is used inside current module > because in such a case if this attribute is not present IPRA will use CC so > it will limit performance benefits from IPRA. Alternatively in this > particular case one can use preserve_all or preserve_most attribute > specified with clang to help IPRA but I believe in some case user may not > be able to describe register usage with such CC then attribute “regmask” > can help. > > For this support I needed to hack clang and LLVM both. How ever it seems > that applicability of this ki...

Hello LLVM Developers, Please feel free to send any ideas that you can think to improve current IPRA. I will work on it and if possible I will implement that. Please consider summary of work done during this week. Implementation: ============ The reviews requests has been updated to reflect the reviews. Testing: ===== To get more benefit from IPRA I experimented it with LTO and results