similar to: [LLVMdev] Choosing an alias analyzer

Hi Pranav, > In lib/Transforms/IPO/PassManagerBuilder.cpp: addInitialAliasAnalysisPasses, > I see this code > ------ > // Add TypeBasedAliasAnalysis before BasicAliasAnalysis so that > // BasicAliasAnalysis wins if they disagree. This is intended to help > // support "obvious" type-punning idioms. > PM.add(createTypeBasedAliasAnalysisPass()); >

Our application generates IR that is used to generate X86_64 code for a Jit. We noticed that code generated with llvm 3.0 is worse in some circumstances that it was with 2.9. I traced the differences to alias analysis differences. Our IR references data structures that have lots of derived pointers and we use extensive tbaa metadata to indicate which pointers dont alias. Some of this seemed to be

On Jan 27, 2012, at 4:15 PM, Maurice Marks wrote: > Our application generates IR that is used to generate X86_64 code for a Jit. We noticed that code generated with llvm 3.0 is worse in some circumstances that it was with 2.9. I traced the differences to alias analysis differences. Our IR references data structures that have lots of derived pointers and we use extensive tbaa metadata to

Many of our pointers point into a structure where they could be considered as having the same base address. We use tbaa to indicate which ones could or could not alias because they are pointing into different substructures. This is exactly the sort of requirement that invoked the need for the restrict modifier in g++, c++0x etc. If I understand you correctly that cannot be expressed in llvm ir

In our case basicaa alone returns "may alias" on our pointers and we want to override that with tbaa data to "Wont alias" when we know that the pointers will never alias. So its not covered by your case. Since the basicaa pass doesnt chain according to the llvm docs, it should have the last chance to affect the aliasing information, and that means it should be added first. If

On Fri, 2012-01-27 at 16:46 -0800, Dan Gohman wrote: > On Jan 27, 2012, at 4:15 PM, Maurice Marks wrote: > > > Our application generates IR that is used to generate X86_64 code for a Jit. We noticed that code generated with llvm 3.0 is worse in some circumstances that it was with 2.9. I traced the differences to alias analysis differences. Our IR references data structures that have

Yes. I've attached an updated patch that does the following: 1. Fixes the partialalias of globals/arguments 2. Enables partialalias for cases where nothing has been unified to a global/argument 3. Fixes that select was unifying the condition to the other pieces (the condition does not need to be processed :P). This was causing unnecessary aliasing. 4. Adds a regression test to

BasicAA treats it conservatively if used on its own. It will return mayalias for the two pointers. TBAA operates based on the guarantee that pointers to different types cannot alias (think C's strict aliasing rules). Therein lies its power but also its danger, that is, nothing prevents the programmer to write code that violates these rules (That's why we have -fno-strict-aliasing). So

> From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] > On Behalf Of Arnold Schwaighofer > Subject: [LLVMdev] inttoptr and basicaa > BasicAA treats it conservatively if used on its own. It will return mayalias > for the two pointers. > TBAA operates based on the guarantee that pointers to different types cannot > alias (think C's strict

On Thu, Jan 15, 2015 at 1:26 PM, Nick Lewycky <nlewycky at google.com> wrote: > On 15 January 2015 at 13:10, Daniel Berlin <dberlin at dberlin.org> wrote: > >> Yes. >> I've attached an updated patch that does the following: >> >> 1. Fixes the partialalias of globals/arguments >> 2. Enables partialalias for cases where nothing has been unified to

Oh, sorry, i didn't rebase it when i changed the fix, you would have had to apply the first on top of the second. Here is one against HEAD On Wed, Jan 14, 2015 at 12:32 PM, Ana Pazos <apazos at codeaurora.org> wrote: > Daniel, your patch does not apply cleanly. Are you on the tip? > > The code I see there is no line if (QueryResult == MayAlias|| QueryResult == PartialAlias)

yes I think that is correct. I wrote a simple program to print if sizeof(uintptr_t) != sizeof(unsigned char *) and when I compile with gcc -m64 and execute it on a 64-bit host (that is different from the 32-bit laptop on which I originally compiled the program), it says the sizes are not equal. Thanks Pranav On Thu, Aug 1, 2013 at 9:29 AM, Alexey Samsonov <samsonov at google.com> wrote:

Dear Alexey, Yes I am sure that the llvm, clang and compiler-rt are synced to the same version. I downloaded them all from git http://llvm.org/docs/GettingStarted.html#git-mirror I think I need compiler-rt for my project but I'll verify it again to see if I can proceed without it. You are correct that compiler-rt is compiled with the just built clang. The complete command that gives an error

Hi, I see that ENABLE_WERROR is being set to off (the default value) in the config.log in the llvm build. However on grepping for WERROR in the compiler-rt folder I get the following output: pranav at pranav:~/smack-project/llvm-3.4/src/projects/compiler-rt$ grep -Rin WERROR * lib/asan/tests/CMakeLists.txt:38: -Werror lib/asan/asan_malloc_mac.cc:253:// This function is currently unused, and we

On Thu, Aug 1, 2013 at 5:32 PM, Pranav Garg <pranav.garg2107 at gmail.com>wrote: > Dear Alexey, > > Yes I am sure that the llvm, clang and compiler-rt are synced to the same > version. I downloaded them all from git > http://llvm.org/docs/GettingStarted.html#git-mirror > I think I need compiler-rt for my project but I'll verify it again to see > if I can proceed

Hi, I am trying to build llvm along with clang and compiler-rt. When I run make, I am getting the following compilation error (I tried compiling llvm-3.2, which is what I need for my project, but also tried llvm-3.3 and the current llvm source from the git repository). ... COMPILE: clang_linux/full-x86_64/x86_64:

Hi Pranav, On Thu, Aug 1, 2013 at 1:54 AM, Pranav Garg <pranav.garg2107 at gmail.com>wrote: > Hi, > > I see that ENABLE_WERROR is being set to off (the default value) in the > config.log in the llvm build. However on grepping for WERROR in the > compiler-rt folder I get the following output: > > pranav at pranav:~/smack-project/llvm-3.4/src/projects/compiler-rt$ grep

On 4/30/2014 5:24 PM, Craig Topper wrote: > Pranav, can you remove it? > Yes, I'll remove it. Pranav -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

Input to this pass is the bitcode format of simple code below : int sum_single_loop (int a){ int su = 0, i; for (i=0;i<a;i++) su = su + i; return su; } On Mon, Feb 9, 2015 at 2:32 AM, David Blaikie <dblaikie at gmail.com> wrote: > > > On Sun, Feb 8, 2015 at 11:23 AM, Pranav Kant <pranav913 at gmail.com> wrote: > >> So, you mean to say that the

You can disable -Werror by adding the cmake flag -DLLVM_ENABLE_WERROR=OFF, which should let it just ignore that (that's also the default, so you must have turned it on somewhere) On Jul 31, 2013, at 13:09 , Pranav Garg <pranav.garg2107 at gmail.com> wrote: > Hi, > > I am trying to build llvm along with clang and compiler-rt. When I run make, I am getting the following