similar to: [LLVMdev] Removing Instructions

Hello! I've discovered that `CallSiteSplitting` optimization doesn't support musttail calls. The easiest fix as it stands is disabling it for such call sites: https://reviews.llvm.org/D43729 . However, I'm not happy with such contribution. My more sophisticated attempt has failed due to my poor understanding of llvm internals. Here is the attempted patch:

The documentation of LLVM says that "The llvm.objectsize intrinsic is lowered to a constant representing the size of the object concerned". I'm attempting to lower this intrinsic function to a constant in a pass. Below is the code snippet that I wrote: for (BasicBlock::iterator i = b.begin(), ie = b.end(); (i != ie) && (block_split == false);) { IntrinsicInst *ii =

Update: I was able to make progress on it today ( See https://reviews.llvm.org/D43729 ). Apparently my problems were: * Iterating through the instruction/block list after erasing block/instruction * Trying to split block after removing one predecessor Regarding the latter, it appears that semantics of `DuplicateInstructionsInSplitBetween` change significantly in such case, and it starts to loop

Hello LLVM Developers, I'm trying to replace a function defined in one module into another module (different files). The first issue I ran into was that llvm::Function does not have a method "moveBefore" or "moveAfter" as the llvm::BasicBlock or llvm::Instruction do, so I figured I would just move the BasicBlocks of the replacing function into the function that was being

Hi, I want to insert a conditional branch in the middle of a basic block. To that end, I am doing these steps: (1) Split the basic block: bb->splitBasicBlock() (2) Remove the old terminator: succ->removePredecessor(bb) bb->getTerminator()->getParent() (3) Adding a new terminator: BranchInst::Create(ifTrue, ifFalse, cnd, "", bb); That seems to work, but later passes

On May 8, 2009, at 4:02 PM, Nick Johnson wrote: > I want to insert a conditional branch in the middle of a basic block. > To that end, I am doing these steps: > > (1) Split the basic block: > bb->splitBasicBlock() > > (2) Remove the old terminator: > succ->removePredecessor(bb) > bb->getTerminator()->getParent() Assuming that the new block will still be a

removeFromParent just unlinks it from the basic block and returns the removed instruction. It does not delete it. On Sun, Jan 20, 2013 at 9:54 PM, David Waggoner <mathonnapkins at gmail.com>wrote: > > Thanks for the suggestion, Duncan. > > I recently figured out that it had to do with how I was removing the > pseudo instruction in my overridden expandPostRAPseudo()

Thanks for your reply. I'm attempting to expand KLEE to support this intrinsic function. That's why I need to handle this myself. According to the reply, the correct implementation should first find the definition of the object and then determine the size of the object. BTW, can I just refer to the implementation in InstCombineCalls.cpp. On Wed, Nov 5, 2014 at 2:24 PM, Matt Arsenault

It's not caused by "the insertion point is set to the default after". I should mention the reason somewhere earlier. "Reversing the order of arg0~3 is not intentional. The user list of pixel_idx happens to have pixel_idx+3, pixel_idx+2, and pixel_idx+1 in this order, so LSR simply follows this order when collecting the LSRFixups." I'm not an expert on uselist orders,

Thanks for the suggestion, Duncan. I recently figured out that it had to do with how I was removing the pseudo instruction in my overridden expandPostRAPseudo() implementation. // member function's signature bool TheInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator p_mi) // works bb.erase(p_mi); // produces the assertion / memory leak. p_mi->removeFromParent(); I should have

I've done some measurements on this. The test program I have just calls Function::Create(), F->setPersonalityFn(), and then F->eraseFromParent() in a loop 2^20 times. Results: pre-patch --- min: 1.10s max: 1.13s avg: 1.11s post-patch --- min: 1.26s max: 1.35s avg: 1.29s So we expect to lose 0.2 seconds per 1 million functions (with personality functions) in a

Hi LLVM, If I have an llvm value "<16 x float> addrspace(1)* %in", and in the LLVM IR, there is a @llvm.dbg.value like: call void @llvm.dbg.value(metadata <16 x float> addrspace(1)* %in, i64 0, metadata !216, metadata !28), !dbg !217 How I can retrieve this @llvm.dbg.value when I have "%in"? Since Metadata is not a part of the uselist anymore, is there some way

I have Function Function* F; and one of its basic blocks BB I want to insert this BB into a new function without remove it from the original according that BList is the list of the basic blocks of the newFunction BList.insert(BB); but I don't want to call BB->removeFromParent(); and without this method it give me error that BB is already in a container is there another function that get

On Mon, 2007-12-03 at 18:56 -0800, Chris Lattner wrote: > Other IR objects (like instructions) have very simple ownership. An > instruction is owned by its basic block, a bb is owned by the function, a > function is owned by thet module. If an instruction is initially allocated with its Instruction *insertAtEnd parameter defaulted to null, and then later appended to a BasicBlock,

I'm writing a peephole pass and I'm done with the X86_64 instruction level detail work. But I'm having difficulty with the basic block surgery of replacing the old MachineInst. The peephole pass gets called per MachineFunction and then iterates over each MachineBasicBlock and in turn over each MachineInst. When it finds an instruction which should be replaced, it builds a new

Here is a WIP patch as promised: http://reviews.llvm.org/D13829 It uses a hungoff uselist to store optional data as needed. Some early objections from Duncan: - An extra one-time malloc() is required to set personality functions. - We get and set personality functions frequently. This patch introduces a level of indirection which slows the common case down. Is this overhead

When trying to display and do anything with a variable of type IntrinsicInst, gdb thinks that it's an incomplete type and kind find any member functions or even display the class. (gdb) list 1337 1332 1333 // Finish off the call including any return values. 1334 return finishCall(CLI, RetVT, NumBytes); 1335 } 1336 1337 bool MipsFastISel::fastLowerIntrinsicCall(const

Hmmm... It seems like I should check out how the UseList on Value (and its child BasicBlock) work. On Tue, May 1, 2018 at 8:34 PM, Keith Wyss <wyssman at gmail.com> wrote: > Hi, > > I'm trying to understand how clang keeps track of which declarations are > called within a translation unit and decides to codegen their definitions. > > DeclBase.h has a markUsed to keep

Yes, it's still respected in this case, as the only instructions that will be deleted have been RAUW with undef. Originally, all instructions where RAUW but only non-EHPad were deleted (that means EHPad were RAUW but not deleted). Then it was later patched by not RAUW token instructions and now not deleting EHPad nor token instructions. My assumption is that the instructions we wanted to

Hi all, I am trying to write a pass where i am creating a clone of a function (the only difference being, the new function returns void , instead of any value). I am creating a new Function Type with a void return type (rest being the same as original function), and using this i am creating a new function body. Then, i clone the body of the old function into new function, but when ever i