similar to: [LLVMdev] How to recognize the declaring code scopes of stack variables

On Thu, Jul 11, 2013 at 9:33 PM, Eric Lu <eirc.lew at gmail.com> wrote: > Hi, David > yes, it is similar to your description. And do you know any methods to do > this in LLVM IR? I don't know the mid-level optimizers especially well - I doubt there's a thing that does exactly what you need - but a combination of existing passes/analyses might be able to tell you what you

On Thu, Jul 11, 2013 at 8:19 PM, Eric Lu <eirc.lew at gmail.com> wrote: > When parallelize the loop with OpenMP like models, I need to know what > variables will be shared among different threads. I imagined you'd want to recognize loops, not scopes. Sounds like a backend kind of optimization type thing, just detecting values that don't escape the loop. (this would catch cases

reg2mem does not eliminate phi nodes the way codegen does, it just converts ssa values to non-ssa values. It's not the same thing. On Tue, Apr 21, 2015 at 10:14 PM, Eric Lu <eirc.lew at gmail.com> wrote: > By the way. When I remove these phi nodes with -reg2mem, some new load > operations will be inserted, but when I try cache load operations with: > visitFunction >

Hi, Daniel I want to profile load/store operations, in order to reduce the overhead of profiling, I try to instrument the optimized llvm ir, which has phi nodes. BTW, when the value of some load/store operations may have multi-source, then the load will be translated into phi nodes, and all phi nodes are placed in the front of BB. Sometimes, the position is not where the load happens, is there

Best Regards! Eric Lew On 周三, 4月 22, 2015 at 12:11 下午, David Blaikie < dblaikie at gmail.com [dblaikie at gmail.com] > wrote: On Tue, Apr 21, 2015 at 8:34 PM, Eric Lu <eirc.lew at gmail.com> wrote: > Hi, all > > I want to instrument load/store operations in LLVM IR. And I find the LLVM > IR generated with flag -o3 is much more efficient than -o0, so I try to >

1) Build clang with GCC-4.9.2, when compling other application s with clang/clang++, the default linker is ld, can I replace it with other linker tool， if we can, how to do it? I.E. can we use collect2 instead? 2) how to specify the path, if we do not use the default vertion GCC? Best Regards! Eric Lew -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi, Ben gcc version is: 4.7.0 clang version is: 3.2 The command options are: 1) clang generated object files: clang -O3 -c *.c -o x.o link: clang *.o -lm -o mpeg2enc 2) gcc generated object files: gcc -O3 -c *.c -o x.o link: gcc *.o -lm -o mpeg2enc Yes, maybe it is the config introduced problems, I build it with enable debug options. Thanks! Eric On Thu, Jun 27, 2013 at 7:49 PM,

Hi Eric,  I was considering machine instructions to get scope information. And variable declaration does not correspond to machine instruction, hence the problem i.e. no scope associated with it. If 'i' is initialized in the 'if-scope' then we get 'variable i' mapped to correct scope as corresponding machine instruction is generated for this. This is not a problem as we

Thank your reply. Pankaj. Actually, I have done it very similar to yours. But I think for my demand, it is better to implement in Front End. Maybe I will re-implement it later in clang. ---------- Forwarded message ---------- From: Pankaj Gode [via LLVM] <ml-node+s1065342n59345h22 at n5.nabble.com> Date: Mon, Jul 15, 2013 at 2:35 PM Subject: Re: Regarding scope information for variable

Hi, all When compiling a program with -g -O0, and if we have a PC, then with addr2line, we can get the line number of the instruction. My quesions are: what is the result of Phi node instruction, can we get the similar results ? -- Best Regards! Eric Lew -------------- next part -------------- An HTML attachment was scrubbed... URL:

On Thu, Jun 27, 2013 at 6:04 PM, Eric Lu <eirc.lew at gmail.com> wrote: > Hi, Ben > gcc version is: 4.7.0 > clang version is: 3.2 > > The command options are: > 1) clang > generated object files: clang -O3 -c *.c -o x.o > link: clang *.o -lm -o mpeg2enc > > 2) gcc > generated object files: gcc -O3 -c *.c -o x.o > link: gcc *.o -lm -o mpeg2enc >

Hi, all I want to instrument load/store operations in LLVM IR. And I find the LLVM IR generated with flag -o3 is much more efficient than -o0, so I try to instrument on these optimized LLVM IR, but, some load operations are changed to Phi loads. Then, I try the -reg2mem flag to remove these phi nodes. The problems are: 1) I use visitLoadInst to collect these load operations, and it seems I

Hello, all When I compile mpeg2enc of Mediabench, it seems clang and llvm take longer time than gcc. I meausre the time as follow: gcc -O3 8.190s clang -O3 20.253s will this means clang and llvm are slower than gcc in compiling c code. Eric -------------- next part -------------- An HTML attachment was scrubbed... URL:

It seems there is no -enable-iv-rewrite now in llvm3.2, and it suggest -enable-load-pre, but it still does not work. So, how to active the transform? -- View this message in context: http://llvm.1065342.n5.nabble.com/indvars-issues-tp4646p58587.html Sent from the LLVM - Dev mailing list archive at Nabble.com.

I have the same demand. Have you resolved this problems? if so, would you share me the solution? Best Regards. Eric -- View this message in context: http://llvm.1065342.n5.nabble.com/Regarding-scope-information-for-variable-declaration-tp47707p59268.html Sent from the LLVM - Dev mailing list archive at Nabble.com.

Hi All,   I have question regarding lexical scope information.   If I have .c source with scope as below. void func() {    //-- some code here..    { //parent scope       if() //high pass       {          int i;          for( i =0; i < FRAM_I; i++)          {          }       }       if() //low pass       {          int i;          for( i =0; i < FRAM_J; i++)          {          }       }

The options is cmake -DCMAKE_BUILD_TYPE="Debug" -DCMAKE_INSTALL_PREFIX=~software/llvmsvn -DCMAKE_EXPORT_COMPILE_COMMANDS=ON /home/xxx/lsoftware/llvm-3.2-svn $make $make install On Fri, Jun 28, 2013 at 12:37 PM, Eric Christopher <echristo at gmail.com>wrote: > On Thu, Jun 27, 2013 at 6:04 PM, Eric Lu <eirc.lew at gmail.com> wrote: > > Hi, Ben > > gcc

On 27.06.2013, at 13:40, Eric Lu <eirc.lew at gmail.com> wrote: > Hello, all > > When I compile mpeg2enc of Mediabench, it seems clang and llvm take longer time than gcc. I meausre the time as follow: > > gcc -O3 8.190s > clang -O3 20.253s > > will this means clang and llvm are slower than gcc in compiling c code. Possibly. The timings are useless without

When compile 403.gcc, there are link errors. 1) environment 1.1) OS Linux gnode107 2.6.18-128.el5 #1 SMP Wed Jan 21 10:41:14 EST 2009 x86_64 x86_64 x86_64 GNU/Linux *1.2) The default GCC compiler is * gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-44) Copyright (C) 2006 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for

Hello, I want to insert a control-block before every outermost loop. My current solution is: 1) find each outermost loop in some function; 2) find the loop header with Loop->getHeader() APIs, and then insert the controller block before the header block of current loop. But I encounters problems when there multi subsequent loops in the following example, where there is no code between loops: