search for: static_single_assignment_form

...? > > -- > Mats > >> >> On 18 March 2016 at 10:42, David Blaikie <dblaikie at gmail.com> wrote: >> >>> Question is hard to understand - the registers in LLVM are in Static >>> Single Assignment form >>> <https://en.wikipedia.org/wiki/Static_single_assignment_form>, they're >>> not variables that can be assigned and reassigned values (so the answer to >>> your question is probably "no"). It's best to look at what Clang does to >>> see how IR can be used to represent constructs in C you may be more >>>...

...ou already know pretty well. http://llvm.org/docs/ProgrammersManual.html http://llvm.org/docs/ You need to know what a phi node is. That is about the only thing that is mostly something you could not just learn from reading the code because it's a special term. http://en.wikipedia.org/wiki/Static_single_assignment_form Reed On 02/21/2013 11:48 PM, Jun Koi wrote: > hi, > > i am reading LLVM code, focusing on the code generation (backend) part. > however, it is still rather tough to understand all the code, so i think > i need to improve my background on compiler backend first. > > any recom...

hi, i am reading LLVM code, focusing on the code generation (backend) part. however, it is still rather tough to understand all the code, so i think i need to improve my background on compiler backend first. any recommendation on good books that introduces all the related techniques used by LLVM: DAG lowering, DAG legalization,instruction selection, scheduling, register allocation, etc... i

I meant LLVM registers. Thanks for the correcting me. On 18 March 2016 at 10:42, David Blaikie <dblaikie at gmail.com> wrote: > Question is hard to understand - the registers in LLVM are in Static > Single Assignment form > <https://en.wikipedia.org/wiki/Static_single_assignment_form>, they're > not variables that can be assigned and reassigned values (so the answer to > your question is probably "no"). It's best to look at what Clang does to > see how IR can be used to represent constructs in C you may be more > familiar with. > > On Thu,...

In any case, Is there any chance for reusing *temporary variable *used in it's IR by LLVM ? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160318/f86ad7b7/attachment.html>

...counter variable ? As Oscar pointed out, you need a phi-node. I read some of the published papers on LLVM before the Language Reference Manual and found them to be of use. You may also find Wikipedia's explanation of SSA useful, especially the key paragraph http://en.wikipedia.org/wiki/Static_single_assignment_form "Note: the phi functions are not actually implemented; instead, they're just markers for the compiler to place the value of all the variables grouped together by the phi function, in the same location in memory (or same register)." Cheers, Ralph.

...decessors here. If you have a loop, some successor (possibly the block of interest) is also a predecessor and must conform to SSA usage. > where should I look at to verify this, the mem2reg.cpp & PromoteMemToReg.cpp? It's an inherent characteristic of SSA: http://en.wikipedia.org/wiki/Static_single_assignment_form (or any of numerous textbooks and papers). - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all c...

Thanks for reply Chuck. Please excuse me if I'm not supposed to reply to all. Are you saying all PHI nodes are required to include all its predecessor blocks no matter they have input or not? What about successor blocks? Are they optional if they don't provide inputs? BTW, where should I look at to verify this, the mem2reg.cpp & PromoteMemToReg.cpp? Thanks a lot. On Sat, Mar 2, 2013

...ttp://llvm.org/docs/ProgrammersManual.html > http://llvm.org/docs/ > > You need to know what a phi node is. That is about the only thing that > is mostly something you could not just learn from reading the code > because it's a special term. > > http://en.wikipedia.org/wiki/Static_single_assignment_form > > Reed > > > On 02/21/2013 11:48 PM, Jun Koi wrote: >> hi, >> >> i am reading LLVM code, focusing on the code generation (backend) part. >> however, it is still rather tough to understand all the code, so i think >> i need to improve my background on c...

Hi, I've read over the "LLVM Language Reference Manual" a few times, and writing some ll code, but i'm stuck at a very basic point. How to decrement a counter variable ? int %count(int %n) { EntryBlock: %cond = seteq int %n, 0 br bool %cond, label %Exit, label %Next Next: ; how to decrement n ? %new_n = sub int %n, 1 br label %EntryBlock Exit: ret int 0 } I guess I

Hi all, Was wondering what is the real benefit of say translating from LLVM's RISC-type instruction set to the x86 which is a more CISC type of design? Especially after emitting said RISC stream from a much higher-level language like say C or C++? I always thought that to efficiently translate logic, as much as possible information has to be retained down the translation chain? Would that not

...out, you need a phi-node. I read some of the > published > papers on LLVM before the Language Reference Manual and found them > to be > of use. You may also find Wikipedia's explanation of SSA useful, > especially the key paragraph > > http://en.wikipedia.org/wiki/Static_single_assignment_form > > "Note: the phi functions are not actually implemented; instead, > they're just markers for the compiler to place the value of all > the > variables grouped together by the phi function, in the same > location > in memory (or same register).&quot...

...ttp://llvm.org/docs/ProgrammersManual.html > http://llvm.org/docs/ > > You need to know what a phi node is. That is about the only thing that > is mostly something you could not just learn from reading the code > because it's a special term. > > http://en.wikipedia.org/wiki/Static_single_assignment_form > > Reed > > > On 02/21/2013 11:48 PM, Jun Koi wrote: >> hi, >> >> i am reading LLVM code, focusing on the code generation (backend) part. >> however, it is still rather tough to understand all the code, so i think >> i need to improve my background on c...