similar to: [LLVMdev] SwitchInst handling in backend

Hi Eli, Thank you for the quick reply. On Feb 27, 2012, at 10:03 PM, Eli Friedman wrote: > SelectionDAGBuilder::visitSwitch is the general switch lowering... I understand this lowering is target independent and there is no additional target dependent handling of switch instructions - right? Only branches and jump tables are left after this lowering? Kind regards, Nico

On Mon, Feb 27, 2012 at 12:52 PM, Nico <listiges at arcor.de> wrote: > Hi, > > if I want to know how switch instructions are handled in the backend, where do I have to look first? > I'm not familiar with the backend framework and I couldn't figure out the interface between the LLVM instruction 'SwitchInst' and whatever there is in the backend. > > I would be

Hi All, Is there a pass in llvm that converts switch statements to if statements? George -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130506/f06741c4/attachment.html>

I mean an llvm Pass that transforms switch statements into if statements. For example, if I have code with switch statements then running the pass will convert all switches to ifs in the bytecode. George On Mon, May 6, 2013 at 4:20 PM, Hal Finkel <hfinkel at anl.gov> wrote: > ----- Original Message ----- > > From: "George Baah" <georgebaah at gmail.com> > >

Hi, Are there some built-in LLVM transformation pass, or written library code that transforms LLVM::SwitchInst into if-condition statements (LLVM:: BranchInst)? The purpose of the transformation is that we have a legacy program analyzer that includes an LLVM pass manipulating if-condition statements. Statements of LLVM::SwithchInst should have been handled in the same manner but was not done.

Hi, I'm interested in any information about implementations of switch instruction and its runtime cost. If it's very target dependent, I'm mostly care about X86. Pointing some LLVM code is also good. - Paweł -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20141027/285f02e5/attachment.html>

----- Original Message ----- > From: "George Baah" <georgebaah at gmail.com> > To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Monday, May 6, 2013 3:09:33 PM > Subject: [LLVMdev] convert switch stmts to If statements > > > > > Hi All, Is there a pass in llvm that converts switch statements to if > statements?

I'm trying to figure out how to feed a blockaddress to a switch condition AND destination (basically emulating an indirectbr via a switch; I know it's not a good approach, I'm just experimenting). Suppose I have the following: SwitchInst *s = SwitchInst::Create(...); BasicBlock *bb = ...; PtrToIntInst k = new PtrToIntInst(BlockAddress::get(bb), <TYPE>, "", s);

There is also the LowerSwitch pass that converts switch instructions to a sequence of branches. On May 6, 2013, at 1:24 PM, George Baah <georgebaah at gmail.com> wrote: > I mean an llvm Pass that transforms switch statements into if statements. For example, if I have code with switch statements then running the pass will convert all switches to ifs in the bytecode. > > George

On Sun, Jul 31, 2011 at 7:36 AM, Carlo Alberto Ferraris <cafxx at strayorange.com> wrote: > I'm trying to figure out how to feed a blockaddress to a switch condition > AND destination (basically emulating an indirectbr via a switch; I know it's > not a good approach, I'm just experimenting). > Suppose I have the following: > > SwitchInst *s =

Hi, all I am interested in how jump-table representated in DAG. I find the method visitJumpTable will Emit JumpTable node in the current MBB. visitJumpTableHeader - This function emits necessary code to produce index in the JumpTable from switch case. but how switch case emits? I would like to make this clearly. Thanks, yaoxiao -------------- next part -------------- An HTML attachment

Nella citazione lunedì 1 agosto 2011 08:13:12, Eli Friedman ha scritto: > On Sun, Jul 31, 2011 at 7:36 AM, Carlo Alberto Ferraris > <cafxx at strayorange.com> wrote: >> I'm trying to figure out how to feed a blockaddress to a switch condition >> AND destination (basically emulating an indirectbr via a switch; I know it's >> not a good approach, I'm just

Hi All, Value* V; Value* V2; BasicBlock * BB; unsigned j; ///number of cases .... //insert V , V2, j and BB SwitchInst* sw= builder.CreateSwitch(V, BB, j); ConstantInt * CI= dyn_cast<ConstantInt>(V2); sw-> addCase( CI , BB); At last step there is Program received signal SIGSEGV, Segmentation fault. What is wrong in the code? Thanks in advance -- * Rasha Salah Omar

Hi all. By now loops with switch instruction are unswitched value-by-value. For example for case range [0..9] we need to run unswitch process 10 times! I want try to optimize that case. Is there any hidden problems that blocks this improvement? Regards, Stepan.

Hi Rasha, > What is wrong in the code? Your best bet is to run a debugger and see if the variables have values you expect just before that last call, and then look at what's causing the segfault in LLVM (null pointer?) code and work out where the first place it's not doing what you expect is. Cheers. Tim.

Hi, I wonder how the initial selection DAG is built in the backends. >From working backends I get: ----8<------- Initial selection DAG: BB#0 'main:' SelectionDAG has 18 nodes: ----8<------- >From my (not working) backend I get: ----8<------- Initial selection DAG: BB#0 'main:' SelectionDAG has 15 nodes: ----8<------- I miss three nodes and I wonder what do I have

Moving to LLVM dev to discuss the possibility of extending the cast infrastructure to handle this. On Tue, Nov 20, 2012 at 5:51 PM, John McCall <rjmccall at apple.com> wrote: > On Nov 18, 2012, at 5:05 PM, David Blaikie <dblaikie at gmail.com> wrote: >> TypeLoc casting looks bogus. >> >> TypeLoc derived types return true from classof when the dynamic type >>

Hi I write a LLVM function pass. The pass will loop the basicblock in the function, check the instruction's type with dyn_cast<switchinst>, print the instruction and the basicblock's successors. I think it is not very complex. My bitcode file is about 30M. My CPU is i7-7700(3.6GHz). It has been running for 60 hours but it is still running. I am not sure whether this is a normal

Hi all, I am slowly working on a SwitchInst optimizer (http://llvm.org/PR8125) and now I am running into a deficiency of the x86 peephole optimizer (or jump-threader?). Here is what I get: andl $3, %edi je .LBB0_4 # BB#2: # %nz # in Loop: Header=BB0_1 Depth=1 cmpl $2, %edi

Since a SwitchInst always has a default case even if no default case appeared in the code, what's the best way to determine if it's explicit or implicit? thanks.. don -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161114/7b2965db/attachment.html>