similar to: [LLVMdev] constructing 'for' statement from LLVM bitcode

Dear Wojciech Matyjewicz: Thank you for your advice. I could follow what you had suggested upto opt -analyze -loops bsloop-opt.bc Therefore, I could get the prints you had showed me as follows: -------------------------------------------------------- Printing analysis 'Natural Loop Construction' for function 'bsloop': Loop Containing: %bb16, %bb13, %bb8, %bb1 Loop

Hello, guys. I am trying to construct higher-level 'for' from the low-level LLVM bitcode(ver 1.9). It's partly successful thanks to David A. Greene's advice suggested to use Control Dependence Graph(CDG). I could find which BB contributes to form which loop with CDG. For example, for this simple function: ----------------------------------------------------------- void bsloop(int

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

Thank you for this comment, Mike. So... your suggestion is to make a valid transform for each loop like: >for (;C;) { > S >} > >is to transform: > >top: >if (!C) goto end; > S >goto top; >end: For now, my code is incomplete so not ready to present for audit yet but I hope it asap. In fact, I couldn't understand what you said: >The cost of the .pdf

I'm attempting to modify a parser generator to emit LLVM code instead of C. So far the experience has been trivial, but I am now running into an error regarding labels that I can't seem to solve. Situation 1: A label is used immediately after a void function call (l6 in this case): <snip> %tmp26 = load i32* @yybegin, align 4 %tmp27 = load i32* @yyend, align 4 call void

Jakub Staszak wrote: > Hi, > > It looks like PDT.getRootNode() returns NULL for: > > define fastcc void @c974001__lengthy_calculation. > 1736(%struct.FRAME.c974001* nocapture %CHAIN.185) noreturn { > entry: > br label %bb > > bb: > br label %bb > } > > > Isn't it a bug in PostDominatorTree? > > Please note that this crashes: >

Hello, Bug is already fixed by Chris (see: http://llvm.org/bugs/show_bug.cgi?id=4915) . I added getRootNode() == NULL condition to my patch. It's not a great solution, but it is enough for now I think. New patch attached. -Jakub -------------- next part -------------- A non-text attachment was scrubbed... Name: dse_ssu-2.patch Type: application/octet-stream Size: 17762 bytes Desc: not

Hi, It looks like PDT.getRootNode() returns NULL for: define fastcc void @c974001__lengthy_calculation. 1736(%struct.FRAME.c974001* nocapture %CHAIN.185) noreturn { entry: br label %bb bb: br label %bb } Isn't it a bug in PostDominatorTree? Please note that this crashes: opt -postdomtree -debug dom_crash.bc I think this should be reported as a bug, -Jakub On Sep 3, 2009, at

Hi, I would like some help regarding the LSR pass. It seems that it likes to duplicate address calculations as in the case above, which is highly undesirable on my target. I wonder if there is any way to tell LSR to not duplicate the code in cases like this? Or could I perhaps run CSE after LSR again? What is the logic behind this transformation? It seems that a LSR pass should not insert a

Try breaking the critical edges (-break-crit-edges). This way, a new block will be created between BB13 and BB11 (call this BB11.break) and BB15 and BB12 (call this BB12.break). The predecessors of the dominance frontier will, thus, be BB11.break, BB12.break, and BB14. When we enter through a block with a call to malloc(), we will end up in one of the blocks in the dominance frontier (kind of).

Hi, I've stumbled upon a case where I think gvn does a bad (wrong) optimization. It's a bit messy to debug though so I'm not sure if I should just write a PR about it a let someone who knows the code look at it instead. Anyway, for the bug to trigger I need to run the following passes in the same opt invocation: -sroa -instcombine -simplifycfg -instcombine -gvn The problem

----- Original Message ----- > From: "Jonas Paulsson" <jonas.paulsson at ericsson.com> > To: llvmdev at cs.uiuc.edu > Sent: Monday, November 26, 2012 1:40:24 PM > Subject: [LLVMdev] LSR pass > > > > > > Hi, > > > > I would like some help regarding the LSR pass. It seems that it likes > to duplicate address calculations as in the

Hi Henrique, I have tried using -mergereturn and inserting a free into the predecessors of dominance frontier of malloc block and it caused double free. It is possible for multiple free's to be inserted on the path from malloc to an exit. For example, in the following CFG: BB10 (malloc) / \ BB11 BB12 ... / \ / \

Hi, The target supports indexing by register or immediate. Multiplications are not supported by any load / store instructions. Would it be possible to make LSR aware of this? Thanks, Jonas Paulsson -----Original Message----- From: Hal Finkel [mailto:hfinkel at anl.gov] Sent: Saturday, December 01, 2012 5:59 AM To: Jonas Paulsson Cc: llvmdev at cs.uiuc.edu Subject: Re: [LLVMdev] LSR pass

On Sep 29, 2010, at 8:35 AMPDT, Ralf Karrenberg wrote: > Hello everybody, > > I have stumbled upon a test case (the attached module is a slightly > reduced version) that shows extremely reduced performance on linux > compared to windows when executed using LLVM's JIT. > > We narrowed the problem down to the actual code being generated, the > source IR on both systems

False Alarm!! Still don't know how to do it! I am trying to write a transformation pass to extract a loop body into a function. For example: The Loop in question is: for (i2 = 0; i2 < LOOP_SIZE; i2++) { A[B[i2]] = 2 * B[i2]; } The IR for which is: bb13: ; preds = %bb13, %bb %i2.0.reg2mem.0 = phi i32 [ 0, %bb ], [ %indvar.next62, %bb13 ] ; <i32>

Hello. I updated my LLVM with version 2.1 from 1.9. But I am curious why I still have signed integer type. I still get LLVM IR as follows: ...... ...... bb8.outer: ; preds = %bb10, %entry %i.0.0.ph = phi uint [ 0, %entry ], [ %indvar.next26, %bb10 ] ; <uint> [#uses=2] %sum.0.pn.ph = phi uint [ 0, %entry ], [ %sum.1, %bb10 ] ; <uint> [#uses=1] br label %bb8 bb3: ; preds = %bb8

David Peixotto <dmp <at> rice.edu> writes: > I am seeing the wf loop get optimized just fine with llvm 2.8 (and almost as good with head). I rechecked this and am I actually seeing the same results as you. I think I must have made a stupid mistake in my tests before - sorry for the noise. However, I found that we have a phase ordering problem which is preventing us getting as much

----- Original Message ----- > From: "Chandler Carruth" <chandlerc at google.com> > To: "Louis Gerbarg" <lgg at apple.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Thursday, May 22, 2014 7:09:49 PM > Subject: Re: [LLVMdev] RFC: Indexing of structs vs arrays in getelementpointer > > > > >

On May 22, 2014, at 3:51 PM, Chandler Carruth <chandlerc at google.com> wrote: > > On Thu, May 22, 2014 at 4:42 PM, Louis Gerbarg <lgg at apple.com> wrote: > The problem that the above transform is technically illegal because “When indexing into a (optionally packed) structure, only i32 integer constants are allowed (when using a vector of indices they must all be the same