search for: instructioncombine

/Volumes/mrs5/net/llvm/llvm/lib/Transforms/Scalar/ InstructionCombining.cpp: In member function ‘llvm::Instruction*<unnamed>::InstCombiner::visitAnd (llvm::BinaryOperator&)’: /Volumes/mrs5/net/llvm/llvm/lib/Transforms/Scalar/ InstructionCombining.cpp:3597: warning: ‘RHSCC’ may be used uninitialized in this function /Volumes/mrs5/net/llvm/llvm/lib/Transforms/Scalar/

Hi all, The InstructionCombining pass causes alignment of globals to be ignored. I've attached a replacement of Fibonacci.cpp which reproduces this (I used 2.3 release). Here's the x86 code it produces: 03C20019 movaps xmm0,xmmword ptr ds:[164E799h] 03C20020 mulps xmm0,xmmword ptr ds:[164E79Ah] 03C20027 movaps xmmword ptr ds:[164E799h],xmm0 03C2002E

On Mon, Feb 23, 2015 at 2:17 PM, Hal Finkel <hfinkel at anl.gov> wrote: > ----- Original Message ----- > > From: "Francois Pichet" <pichet2000 at gmail.com> > > To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > > Sent: Sunday, February 22, 2015 5:34:11 PM > > Subject: [LLVMdev] Question about shouldMergeGEPs in

Hello I am not sure I understand the logic for merging GEPs in InstructionCombining.cpp: static bool shouldMergeGEPs(GEPOperator &GEP, GEPOperator &Src) { // If this GEP has only 0 indices, it is the same pointer as // Src. If Src is not a trivial GEP too, don't combine // the indices. if (GEP.hasAllZeroIndices() && !Src.hasAllZeroIndices() &&

Hi, This is regarding a TODO mentioned in getIdentityValue function in InstructionCombining.cpp file. //TODO: We can handle other cases e.g. Instruction::And, Instruction::Or etc. I wanted to know what could be the use cases of implementing these. When I tried implementing these and wrote test cases for the same, the test cases would be optimized in InstructionSimplify before hitting the code

I think I found it. In InstCombiner::ComputeMaskedBits we have the following lines: if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) { unsigned Align = GV->getAlignment(); if (Align == 0 && TD && GV->getType()->getElementType()->isSized()) Align = TD->getPrefTypeAlignment(GV->getType()->getElementType()); It assumes that global

InstCombine says in its getAnalysisUsage that it preserves the CFG, but for the 4th argument in its INITIALIZE_PASS call, it says false, which I believe corresponds to whether it preserves the CFG. Is this a mistake, or is there deeper meaning here? InstructionCombining.cpp:73-82 char InstCombiner::ID = 0; INITIALIZE_PASS(InstCombiner, "instcombine", "Combine

If you're able to reproduce the infinite loop with -O3 then you should be able to dump out the IR that causes `opt -instcombine` to infloop, unless the bug is truly esoteric (e.g. only caused by a specific use-list ordering). Maybe take a closer look at the output from `opt -print-before-all -O3`? Alternatively you can use bugpoint to minimize the IR to get a small reproducer that causes

...y idea about the performance impact and other consequences that if we remove such a canonicalization pass. In my option, it should not be important since we still run the "InstructionCombining" pass after "createLoopRotatePass" pass and in fact there are many more runs of "InstructionCombine" pass after this point. Best, Star Tan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130913/32a89a62/attachment.html>

----- Original Message ----- > From: "Hal Finkel" <hfinkel at anl.gov> > To: "Francois Pichet" <pichet2000 at gmail.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu>, "chandlerc" <chandlerc at gmail.com> > Sent: Tuesday, February 24, 2015 11:27:43 PM > Subject: Re: [LLVMdev] Question about

...y idea about the performance impact and other consequences that if we remove such a canonicalization pass. In my option, it should not be important since we still run the "InstructionCombining" pass after "createLoopRotatePass" pass and in fact there are many more runs of "InstructionCombine" pass after this point. Best, Star Tan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130914/a2bf7a5f/attachment.html>

Hi Michael, > InstCombine says in its getAnalysisUsage that it preserves the CFG, > but for the 4th argument in its INITIALIZE_PASS call, it says false, > which I believe corresponds to whether it preserves the CFG. that argument should be set to true if the pass only looks at the CFG, i.e. whatever it computes/does is only a function of the CFG, and doesn't otherwise depend on what

Hi Bill- For what it's worth, a simple truth table proves Chris correct. Alastair On 5 Jan 2010, at 02:46, Bill Wendling wrote: > On Jan 3, 2010, at 10:04 PM, Chris Lattner wrote: > >> Author: lattner >> Date: Mon Jan 4 00:03:59 2010 >> New Revision: 92458 >> >> URL: http://llvm.org/viewvc/llvm-project?rev=92458&view=rev >> Log: >>

Hi Nicolas, > if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) { > > unsigned Align = GV->getAlignment(); > > if (Align == 0 && TD && GV->getType()->getElementType()->isSized()) > > Align = TD->getPrefTypeAlignment(GV->getType()->getElementType()); > > It assumes that global values are always optimally

Hi Duncan, I see. I didn't know GlobalValue had a method for changing the alignment (and that 0 meant natural alignment). Explicitly calling setAlignment works like a charm. So it's not an LLVM bug. Thanks, Nicolas -----Original Message----- From: Duncan Sands [mailto:baldrick at free.fr] Sent: Thursday, 10 July, 2008 14:41 To: llvmdev at cs.uiuc.edu Cc: Nicolas Capens Subject: Re:

On Thursday 10 July 2008 07:46, Nicolas Capens wrote: > Hi Duncan, > > I see. I didn't know GlobalValue had a method for changing the alignment > (and that 0 meant natural alignment). Explicitly calling setAlignment works > like a charm. Nicolas, Where are you explicitly calling setAlignment? From llvm-gcc code? -Dave

Hi Sanjay, 2017-01-30 22:22 GMT+01:00 Sanjay Patel <spatel at rotateright.com>: > My minimal patch idea is to ease the restriction in ShouldChangeType > because i1 is special. I tried the patch below, and it works on the > example...and nothing in 'make check' failed. :) > Yeah, that would work for me as well, I just wasn't sure about the implications that has.

Hi all. Guys in accordance to PR1255 I need to add case-ranges support for passes listed in subject. Who can review some of these passes in nearest future? Thanks! -Stepan.

ISSUE: This code: %bob = type { int } int %alias() { %pbob1 = alloca %bob %pbob2 = getelementptr %bob* %pbob1 ;pbob2 aliases pbob1 %pbobel = getelementptr %bob* %pbob2, long 0, ubyte 0 %rval = load int* %pbobel ret int %rval } Crashes when run through opt -instcombine. InstCombiner visits instructions in reverse declaration order, but

...y idea about the performance impact and other consequences that if we remove such a canonicalization pass. In my option, it should not be important since we still run the "InstructionCombining" pass after "createLoopRotatePass" pass and in fact there are many more runs of "InstructionCombine" pass after this point. Best, Star Tan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130917/95c19526/attachment.html>