similar to: [LLVMdev] predefined pass for transforming a module to SSA?

Hello, Ying. > But if a module is constructed by hand, how can I transform it into a > SSA-based llvm? LLVM IR is *always* in SSA form, even if you're constructing module by hands (Verifier pass actually does the check and reject invalid code). If you want to eliminate memory accesses and transform them to registers & phi's you might want to run mem2reg pass also. -- With best

Hi everyone, Llvm-gcc compiles the programs into bytecodes with some optimizations. How can I get unoptimized bytecodes? Thanks. Regards, -Ying -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20070530/5f793e95/attachment.html>

Using llvm-gcc -emit-llvm -O0 -S blah.c will give you blah.s that is unoptimized. I guess passing that to llvm-as would get you an unoptimized .bc. llvm-as -debug-pass=Arguments blah.ll says it is only doing Pass Arguments: -domtree -etforest -verify scott On 5/29/07, omiga <omiga at ustc.edu> wrote: > > Hi everyone, > > Llvm-gcc compiles the programs into bytecodes with

Hello. Please use llvm-gcc4 with -O[01234] options. You can see the example here: http://llvm.org/docs/GettingStarted.html#tutorial4 Seung J. Lee ---- Original message ---- >Date: Wed, 30 May 2007 00:18:41 +0800 >From: "omiga" <omiga at ustc.edu> >Subject: [LLVMdev] (no subject) >To: "llvmdev" <llvmdev at cs.uiuc.edu> > > Hi everyone, >

If you use llvm-gcc3, you can make an unoptimized like this: llvm-gcc -S hello.c -o hello.s Seung J. Lee ---- Original message ---- >Date: Wed, 30 May 2007 00:18:41 +0800 >From: "omiga" <omiga at ustc.edu> >Subject: [LLVMdev] (no subject) >To: "llvmdev" <llvmdev at cs.uiuc.edu> > > Hi everyone, > > Llvm-gcc compiles the programs

Sorry for the confusion, Misha seemed to answer my question in one way. It'll be easier if I break down my question into parts - - Is it possible to see the SSA form generated for my program ? - Now, if this form is readable, is it in assembly code format ? We want to look at the SSA form for any program and see if we can make some changes ourselves to that format so that its reflected in

Hi, Sorry if this question has been asked earlier: Is the -reg2mem the pass to convert SSA form of LLVM IR to non-SSA form (ie, eliminate all phi-functions from LLVM IR) ? I tried it with a small example and it did remove all the phi function, I just wanted to confirm that the pass guarantees to remove all phi functions. Also, assuming I have this pass as a required pass, is it safe to clone

Hello, I am new to LLVM. Since memory locations are not in SSA form. I was wondering if there is any attempt of transforming LLVM IR in memory SSA form? Regards Umer -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20131105/3f5adb37/attachment.html>

Dear LLVM'ers, I'm producing code for the PowerPC, and many often times it happens that the bytecodes generated by LLVM have phi-functions like: A4 = phi(A1, A2) A5 = phi(A1, A3) Where the 'A1' parameter appears in two different phi-functions. Could someone give me an example in "pseudo-assembly" that would produce code like that after being transformed into

Memory is what the i32* points too. The i32* itself is in a register. You can store to it as many times as you want, but you can't change the address, because that would violate SSA. On Jul 17, 2008, at 4:26 AM, Matthieu Moy wrote: > [ sorry for the late reply ] > > Patrick Meredith <pmeredit at uiuc.edu> wrote: >> All register uses are SSA. Memory is not in SSA.

All register uses are SSA. Memory is not in SSA. The mem2reg pass which promotes stack variables to registers effectively converts non- SSA to SSA. There was a reg2mem pass, written by Andrew Lenharth, I'm not sure if it's still being maintained. On Jul 7, 2008, at 8:47 AM, Matthieu Moy wrote: > Hi, > > Silly question from an LLVM newbie: the LLVM LRM say that the

Thanks for the explanation. It's more clear now The only thing that seems strange is that in the function llvm_expand_shortcircuit_truth_expr in the front end, there is the creation of a PHI instruction. If there is no SSA yet, why do you do that? Thanks in advance --- John Criswell <criswell at cs.uiuc.edu> wrote: > Ricardo wrote: > > Hi, > > > > I have been

Ricardo wrote: > Hi, > > I have been looking into the code that generates the LLVM assembly in the LLVM front end, but I am > not very sure if at the time that the llvm_c_expand_body_1 function is called, the SSA form was > already constructed (each definition dominates all the uses). Can somebody please tell me? The LLVM GCC frontend does not translate variables directly into

Chris and everyone else, Below I summarize my understanding of what llvm does when converting to SSA and a clarification on why backward dataflow analyses can not be performed on "just" SSA. >> Scalar variables still have a stack location associated with them, >> don't they? > > No, they don't. All scalar values in LLVM represent "virtual >

[ sorry for the late reply ] Patrick Meredith <pmeredit at uiuc.edu> wrote: > All register uses are SSA. Memory is not in SSA. The mem2reg pass > which promotes stack variables to registers effectively converts non- > SSA to SSA. There was a reg2mem pass, written by Andrew Lenharth, I'm > not sure if it's still being maintained. What is the difference between

Hi, Silly question from an LLVM newbie: the LLVM LRM say that the bytecode is "is an SSA based representation". Indeed, my experience with llvm-gcc is that the generated code is not necessarily SSA, while the one given by "llvm-gcc -O1" is. Is this assumption correct? Is there a non-SSA to SSA translator available? Thanks, -- Matthieu

I tried using the mem2reg pass with opt, e.g. opt -reg2mem x.bc > x2.bc where x.bc was produced with: llvm-gcc -O2 -emit-llvm -c x.c -o x.bc This did not reduce the # of variables in x2.bc I use -O2 because it produces the least # of instructions and hence the least # of new SSA virtual registers. Do you have a set of options to give to llvm-gcc or opt in mind ? My goal is to take a .c

I am familiar with the LLVM IR a little bit and I am parsing much more complex examples. I just gave this example, to show that I would like to have only 1 variable, not 2, the way SSA would generate it. I am actually using LLVM purely as a front end to translate to .bc files and then I have my own parser from there. At any rate, is there an option to the llvm-gcc --emit-llvm to tell it to

On 3/29/11 12:26 PM, George Baah wrote: > Hi All, > When I run the following command > llvm-gcc -03 -emit-llvm test.cpp -c -o test.bc or llvm-gcc -emit-llvm > test.cpp -c -o test.bc > > on the program test.cpp, the IR representation is not in SSA form. > I do not see any phi functions. Actually, it is in SSA form (or more precisely, the virtual registers are in SSA form;

Hello, for some my use case, I'd like to temporary break SSA property and then ask LLVM to restore it. Here's more details: if (i < 0) { i = -i; } This is a C code example. I'm trying to create a value range analysis, which will determine, that after this code, 'i' is non-negative. In SSA form, this will become i = 0; if (i < 0) { i.2 = -i; }