similar to: how LLVM deals with 'undef'

Hi, I just tried llvm-3.8 (LLVM SVN Repository). With this version, -fno-rtti can help me to compile my code and -irce can help me to do a better job for loop unrolling. However, I still have one question. If I use Clang to compile a piece of c++ code to .bc and then use 'opt -loop-rotate -loop-unroll -irce', I can get what I want. I mean, there is no conditional branch at the end of each

Thanks for your point that out. I just add DataLayout in my code such as "mod->setDataLayout("e-m:e-i64:64-f80:128-n8:16:32:64-S128");", still no luck. I'm really confused about this. Do I need to add more passes before -loop-unroll? On Sat, Aug 22, 2015 at 11:36 AM, Mehdi Amini <mehdi.amini at apple.com> wrote: > > On Aug 22, 2015, at 7:27 AM, Xiangyang

Hi, Mehdi, For example, I have this very simple source code: void foo( int n, int array_x[]) { for (int i=0; i < n; i++) array_x[i] = i; } After I use "clang -emit-llvm -o bc_from_clang.bc -c try.cc", I get bc_from_clang.bc. With my code (using LLVM IRbuilder API), I get bc_from_api.bc. Attachment please find thse two files. I also past the IR here.

There's been some recent noise on the mailing list about requiring -fno-rtti; http://lists.llvm.org/pipermail/llvm-dev/2015-August/089010.html Could that be it? On Sat, Aug 22, 2015 at 12:21 AM, Xiangyang Guo via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Hi, James and Philip, Thanks for your help. > > Based on your advice, I downloaded llvm-3.7. However, with this new

Hi Xiangyang, The algorithm for loop unrolling was changed post-3.5 to do more what you'd expect. If you use 3.6 or 3.7 you'll likely get better results. Cheers, James On Thu, 20 Aug 2015 at 18:09 Philip Reames via llvm-dev < llvm-dev at lists.llvm.org> wrote: > On 08/20/2015 07:38 AM, Xiangyang Guo via llvm-dev wrote: > > Hi, > > I want to use loop unrolling

Hi, I want to use loop unrolling pass, however, I find that loop unrolling will introduces conditional branch at end of every "unrolled" part. For example, consider the following code *void foo( int n, int array_x[])* *{* * for (int i=0; i < n; i++)* * array_x[i] = i; * *}* Then I use this command "opt-3.5 try.bc -mem2reg -loops -loop-simplify -loop-rotate -lcssa

Thanks for your reply, escha, Yes, -loop-rorate makes it work. Regards, Xiangyang 2015-12-01 12:48 GMT-05:00 <escha at apple.com>: > > > On Dec 1, 2015, at 9:30 AM, Xiangyang Guo via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > > > Hi, All, > > > > Suppose I define one memory read only intrinsic function "foo" in >

Hi, All, Suppose I define one memory read only intrinsic function "foo" in Intrinsics.td like this def int_foo : Intrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i32_ty], [IntrReadMem]>; Suppose I have the following IR, which means the intrinsic function "foo" is called 10 times in a loop. Since the parameters of function "foo" are invariant and the function

Hi, All, Our team within the Software and Services Group at Intel is looking for compiler engineers to join us. Currently two positions are available, see attached links. If you are interested, you can apply online or email me at xiangyang.guo at intel.com. Thanks. --Xiangyang (Mark) Guo

Hi, Diego, Thanks for your quick reply. Inserting a copy instruction may not work here because I have a limitation of virtual register number. I need to assign registers with ssa form to registers without ssa form. I will look the source code you point out. Thanks Xiangyang On Fri, Apr 24, 2015 at 4:19 PM, Diego Novillo <dnovillo at google.com> wrote: > > > On Fri, Apr 24, 2015

Hi, All, I want to lower 64 Bits constant such as 'long' and 'double'. So I define them like this: def CONSTI64 : InstFOO<(outs GRWideRegs:$dst), (ins i64imm:$src), "const-long $dst, $src", [(set (i64 GRWideRegs:$dst), imm:$src)]>{ let isMoveImm = 1; } def CONSTF64 : InstFOO<(outs

Hi, When I define an intrinsic function with memory write permission, my assumption is that we can either attach [IntrReadWriteArgMem] or [] to the intrinsic function. Based on the comment of the source code , "IntrReadWriteArgMem - This intrinsic reads and writes only from memory that one of its arguments points to, but may access an unspecified amount." "If no property is set,

On 1 December 2015 at 12:33, Xiangyang Guo via llvm-dev <llvm-dev at lists.llvm.org> wrote: > if I have the following IR, LICM doesn't work again, even if I use > '-loop-rotate' firstly. In this IR, the return value of intrinsic function > "foo" is used by another function "func2" as parameter. However, for the > intrinsic function

Hello, I'm using bwplot to make a few plots. The plots are exactly what I need, but are coming out with a grey background and turquoise boxes and whiskers. I cannot figure out how to just get black and white to be the default. Can anyone help me with this? Thanks Kenneth E. Nussear Phone 775 784-1703 Ecology, Evolution and FAX 775 784-1369

Hi, Assume I define registers R0...R15 and two register classes RegA and RegB. RegA contains R0 to R7 while RegB contains R0 to R15. Then I check the machine instruction, it seems that in some cases, the %vreg0 belongs to RegB; in other cases %vreg1 belongs to RegA_RegB. Can you tell me how TableGen decides which is which? At first, I guess &verg0 will be assigned by R8 to R15 only so that

Hi, Assume I have the following code. The first four instructions in each BB does the same thing. So I think GVN() can remove the redundant code. However, after I apply GVN to my module by "Passes.add(createGVNPass())" and "Passes.run(*myModule)". It seems GVN does not remove the redundant instructions. Can anyone give me a hint what's going on here? Any hint is

Thanks for your reply, Philip. You are right, when I use LLVM-3.8, the 'argmemonly' shows up. Previously, I use LLVM-3.7. I think idempotent is what I want. Can you tell me how to add idempotent attribute to the function? Thanks. Regards, Xiangyang 2016-03-24 14:30 GMT-07:00 Philip Reames <listmail at philipreames.com>: > > > On 03/24/2016 12:45 PM, Xiangyang Guo via

The following is a patch I've been working on to support a "ChrootUser" option in the sshd_config file. I was looking for a way to offer sftp access and at the same time restict interactive shell access. This patch is a necessary first step (IMO). It applies clean with 'patch -l'. Also attached is a shell script that helps to build a chrooted home dir on a RedHat 7.2

Hi, I want to convert LLVM IR to another type of IR, which has no SSA form. So the most important thing I need to handle is Phi node and register allocation because another type of IR has a limitation of virtual register number. The first thing I can think about is to learn how LLVM Backend works because LLVM Backend handles these things. But I'm not familiar with Backend. After reading some

Hi list, I'm trying to get R to make a graph like the one shown in this pdf, where males are white bars and females are black bars. http://www.brrc.unr.edu/~knussear/mmgraph.pdf I tried barchart, but I couldnt get the bars to share a common x axis. Do you have any suggestions? Thanks for your help Ken