similar to: [LLVMdev] Emit a jump instruction to a place inside basicblock

On Thu, Oct 30, 2014 at 2:33 PM, Robin Morisset <morisset at google.com> wrote: > Hi, > > From my understanding of the LLVM IR, it is impossible to jump to the > middle of a Basic Block, only to its beginning. But there is a > splitBasicBlock function that seems like it might be useful to you, to make > sure a basic block is starting at the exact place you want to jump.

On Thu, Oct 30, 2014 at 4:48 PM, Eric Christopher <echristo at gmail.com> wrote: > > > On Thu Oct 30 2014 at 1:16:38 PM Xiaoguang Wang <xgwang09 at gmail.com> > wrote: > >> On Thu, Oct 30, 2014 at 2:33 PM, Robin Morisset <morisset at google.com> >> wrote: >> >>> Hi, >>> >>> From my understanding of the LLVM IR, it is

Hi all, I'm a beginner in LLVM. I read a paper recently, and I'm trying to use LLVM jumptable in 3.5. When I compile the .bc file into .s file, I tried to use the different jumptable type: all, single, ... e.g. clang -c -emit-llvm test.c llc test.bc -jump-table-type=full -o test-full.s llc test.bc -jump-table-type=single -o test-single.s The tested C source code is like: void foo() {

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

The clone llvm:CloneBasicBlock copies the phi function in the replicated basic block from the original basic block. I don't want the copy of phi in relplicated block. For now I am creating .bc file with -O0 option so that it doesn't generate phi function in first place. Is this a good approach or there are some other function available for it. Tarun On Sun, Apr 17, 2011 at 5:22 AM, Eli

Hi, I am writing a pass for constant propagation using graph restructuring ( code duplication). I am facing following difficulties.. 1) I need to replicate the basic block but without phi function in the replicated block. How can I do this. 2) I need to insert that basic block after and before some particular basic block. Regards Tarun Agrawal -------------- next part -------------- An HTML

Hi list: I have been trying to get my feet wet with the ARM backend. As a warmup exercise I wanted to be able to move jumptables especially large ones out of the code section. Currently the idiom for jump tables loooks like this // .set PCRELV0, (.LJTI9_0_0-(.LPCRELL0+8)) // .LPCRELL0: // add r3, pc, #PCRELV0 // ldr pc, [r3, +r0, lsl #2] // .LJTI9_0_0: //

Hi everyone, I''m trying to start up domU on xen for ARM (Cortex-A15 Fast models). I follow the instructions to build xen-tools with this link: http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions/CrossCompiling. But there seems to be something wrong when I start up domU. First, I get errors in create domU with xl: root@(none):/home/xiaogw# xl create domU-config xc: error:

On Sat, Apr 16, 2011 at 4:32 PM, tarun agrawal <tarun at cse.iitb.ac.in> wrote: > Hi, > > I am writing a pass for constant propagation using graph restructuring ( > code duplication). I am facing following difficulties.. > > 1) I need to replicate the basic block but without phi function in the > replicated block. How can I do this. > > 2) I need to insert that

On Sat, Apr 16, 2011 at 5:01 PM, tarun agrawal <tarun at cse.iitb.ac.in> wrote: > The clone llvm:CloneBasicBlock copies the phi function in the replicated > basic block from the original basic block. > I don't want the copy of phi in relplicated block. For now I am creating .bc > file with -O0 option so that it doesn't generate phi function in first > place. Is this a

Hi Robin, On 15 August 2014 21:49, Robin Morisset <morisset at google.com> wrote: > I have > attached the corresponding patches; they are not completely ready for review > (mostly missing tests), I would just like to make sure that the general > approach seems reasonable. I've had a quick glance at the patches, and the code seems fairly sane. But I'm not so sure about

Hi, I found a problem in CodeExtractor::severSplitPHINodes() <CodeExtractor.cpp>. The algorithm first separates the header block into two, one containing only PHI nodes and the other containing the remaining non-PHI nodes. The variable NewBB holds the pointer to the latter half block. Later, it tries to update DT information. if (DT) DT->splitBlock(NewBB); In splitBlock, it checks

On Nov 19, 2008, at 7:41 AM, Jack Tzu-Han Hung wrote: > Hi, > > I found a problem in CodeExtractor::severSplitPHINodes() > <CodeExtractor.cpp>. > > The algorithm first separates the header block into two, one > containing only PHI nodes and the other containing the remaining non- > PHI nodes. The variable NewBB holds the pointer to the latter half > block.

On 4/16/11 7:01 PM, tarun agrawal wrote: > The clone llvm:CloneBasicBlock copies the phi function in the > replicated basic block from the original basic block. After you clone the basic block, you can probably replace the phi instruction with another value of your choice. If you're adding variables, you'll probably want to create them as allocas and use loads and stores to

Thanks for the background on the concurrent memory model. So, is it sufficient that the loop entry is guarded by condition (cbz at top) for preventing the race? The loop entry will be guarded by condition if loop has been rotated by loop rotate pass. Since LICM runs after loop rotate, we can use ScalarEvolution::isLoopEntryGuardedByCond to check if we can speculatively execute load without

On Mar 1, 2010, at 10:52 AM, Richard Osborne wrote: > On 23/02/10 14:58, Richard Osborne wrote: >> I've recently changed the XCore target to implement BR_JT as a jump to a >> series jumps. The jump table entries are expand inline in the function >> so there is no longer a need to emit jump tables at the end of the >> function. However the emission of jump tables at

On Mar 1, 2010, at 4:09 PM, Richard Osborne wrote: > On 01/03/10 21:14, Chris Lattner wrote: >> On Mar 1, 2010, at 10:52 AM, Richard Osborne wrote: >> >>> On 23/02/10 14:58, Richard Osborne wrote: >>> >>>> I've recently changed the XCore target to implement BR_JT as a jump to a >>>> series jumps. The jump table entries are

Hi, I'm not sure if this is really a problem or not, but I noticed that if you're working with bitcode that has debug metadata, and you split a BasicBlock using llvm::SplitBlock or BasicBlock::splitBasicBlock, the unconditional branch added to the new block will lack debug metadata. This turned out not to be a problem for me, since my analysis pass needs only one instruction in

There might be a misuse of DominatorTree::splitBasicBlock in CodeExtractor.cpp, line 145. Header is splited into two (OldPred->NewBB). Line 145 updates the dominator tree by calling DT->splitBasicBlock(NewBB). I think it should be DT->splitBasicBlock(OldPred). When I tried to extract a code region whose header has 2 successors, my pass crashed. It was because header (or OldPred) is the

Hi, I have been trying to move some instructions between basic blocks , After looking at the API , I found llvm::Instruction::clone() but there is no result value for this. For example- source Basic block : continuation: ; preds = %else, %then %iftmp = phi i32 [ 5, %then ], [ 9, %else ] store i32 %iftmp, i32* %datasize ; 3 instructions below