similar to: [LLVMdev] Reg2Mem pass

On Fri, 2007-08-10 at 00:51 -0500, Seung Jae Lee wrote: > Hi, guys. > > I'm interested in using reg2mem pass but not sure about the concept of it. > Can you let me know a reference about it, if any? > Forgive my ignorance. -_-; The reg2mem pass undoes SSA form. That is, it turns SSA registers into alloca instructions with loads and stores. > > Thanks, > Seung J.

Hello, guys. I just tested -reg2mem pass to see how it changes my bitcode. E.g., for the following simple C code: ------------------------------------------------------------- int foo() { int i,j; int sum = 0; for (i=0; i<10; i++) { sum += i; for (j=0; j<3; j++) sum += 2; } return sum; } ------------------------------------------------------------- I could get the

Hello. My name is Seung Jae Lee. I'd like to ask you onething about converting to ARM assembly code. I saved the simplest C code shown in your LLVM webpage as 'hello.c' And I made 'hello.bc' by "$ llvm-gcc hello.c -o hello". In order to make ARM assembly code, I typed "llc -march=arm hello.bc -o hello.arm" But, I met this error. llc: ARMISelDAGToDAG.cpp:73:

Hello, LLVMers. I have a quick question for constant folding. When I treated a code twice by changing the data type from 'floating point' to 'integer,' What I found was: optimization is done better for the code having int's. E.g., for this simple code: ------------------------------------------------------------- double foo() { double i,j; double sum = 0; for (i=0;

Xi, I just installed VS2005 pro w/ SP1 for Win Vista. Thanks, Seung ---- Original message ---- >Date: Fri, 22 Feb 2008 12:36:43 +0800 >From: "Xi Wang" <xi.wang at gmail.com> >Subject: Re: [LLVMdev] Is there someone tried LLVM 2.1 on Visual Studio 2005? >To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > >I'm sorry but did you

On the document about writing an LLVM backend, I became to wonder what the 'virtual register' is in the following statement. "You also need to define register classes to contain these registers, such as the integer register class and floating-point register class, so that you can allocate virtual registers to instructions from these sets, and let the target-independent register

Can you recommend any good book or reference for backend implementation? I skimmed some compiler books but it seemed to be more about front-end, parsing, optimization etc. Would you mind suggesting some books containing more about backend? Thank you.

Dear Prof.Adve and Bill, I deeply appreciate your comments and concerns. (Please forgive my late response. I've tried some more cases to make this issue) As Prof.Adve mentioned, I need to explain exactly what my problem is, but I have no good ability that I can explain it in this plain text space. For this reason, I made a .pdf file and linked it as follows:

Hello. Nice to meet you. My name is Seung Jae Lee, a graduate student in UIUC CEE, who is working in NCSA for the present. Nowadays I am trying to develop LLVM backend to spit out CHiMPS assembly code. In the process, I installed LLVM codes on my home directory in the host computer. But I don't think it was installed properly. While bootstrapping the LLVM C/C++ Front-End, I met several

Is there a pass I can use after reg2mem to get rid of occurances like this?: store i32 %cond, i32* %cond.reg2mem %cond.reload = load i32* %cond.reg2mem store i32 %cond.reload, i32* %cond4.reg2mem Essentially, in this case, reg2mem creates an extra memory space to store and load a value from just here, and never uses the value again; since this isn't efficient code, I'm wondering if

Hello. I am trying to run tblgen so I typed $ tblgen ARM.td -print-enums -class=Register in "llvm/lib/Target/ARM" But I got an error as follows: Included from ARM.td:18: Parsing ../Target.td:16: Could not find include file 'llvm/Intrinsics.td'! As you know, the 16th line of Target.td includes "llvm/Intrinsics.td". But this cannot find Intrinsics.td, I think. Of

Thank you for this information. If so, is there any way to grasp which kinda data throw in and out in LLVM as shown in such a way in gdb? Thanks, Seung Jae Lee ---- Original message ---- >Date: Tue, 20 Feb 2007 23:54:04 -0600 >From: "John T. Criswell" <criswell at cs.uiuc.edu> >Subject: Re: [LLVMdev] bugpoint usage >To: LLVM Developers Mailing List <llvmdev at

Hello, LLVMers. I just wonder How I can pronounce Clang. [see-laeng], [see-lang], [k-laeng], [k-lang]?? Thanks, Seung

Thank you, Bill. Seems to be better. Anyway...Is there a way I can do what you showed for me? Thanks, Seung J. Lee ---- Original message ---- >Date: Sat, 26 Jan 2008 22:10:01 -0800 >From: Bill Wendling <isanbard at gmail.com> >Subject: Re: [LLVMdev] Question to Chris >To: LLVM Developers Mailing List <llvmdev at cs.uiuc.edu> > >On Jan 26, 2008, at 9:48 AM, Seung

Thanks for your comment. I also tried for LLVM 2.2 but got the same compilation errors on VS2005. (I didn't modify anything before the compilation) I just wonder if I need bison and flex even just in the case of compiling them on VS2005 without changing anything because the LLVM doc says "If you plan to modify any .y or .l files, you will need to have bison and/or flex installed where

Hi, I work on a pass that requires as input LLVM code without any phi nodes. For this, I use the reg2mem pass which produces suitable code, the pass runs correctly, but I obtain a significant performance decrease. I expect that this is because there are more reads / writes to memory after running the reg2mem pass. How can I optimize the code, without inserting any phi nodes? Or is there a

I followed the steps in "Getting Started with the LLVM System using Microsoft Visual Studio" in the document in LLVM page. I made hello.c file exactly same shown in the page. I made hello.bc on UNIX and transferred it to my Windows computer. And I typed "llc -march=c hello.bc" (Of course, I downloaded the latest version of LLVM and compiled with VS before this.) But my command

I am currently building a BasicBlock pass which requires to run -reg2mem before it, and need to run -mem2reg after it to clean up. So, I want to specify -reg2mem as one of the pre-requisite passes to it, as: class MyPass: public BasicBlockPass{ virtual void getAnalysisUsage(AnalysisUsage &AU){ ... AU.addRequired<RegToMem>(); ... } }; I searched all passes under

I have always built it with flex and bison installed, though I believe Chris removed our last dependence on flex a little while back, so you may not need that. I'm using bison 2.1 which I got from the getgnuwin32 folks. I imagine that if you have cygwin or the like, you probably already have everything. You will need to have the executables in your path. I build with VisualStudio 2k5

Thank you so much for your reply, Chris. If so, can I ask you two things more? First, is there any way to have various optimizations on LLVM assembly such as -O options in llvmc? llvm-gcc doesn't seem to be working for these -O options... Second, I'm still not sure about difference between *.s and *.ll. LLVM assembly *.s file can be made from llvm-gcc -S. Another assembly *.ll file comes