similar to: [LLVMdev] Predication bug in AggressiveAntiDepBreaker?

I saw there is reference to dead def on registers in LLVM source code. I am not aware of this concept from the traditional course material. What are the properties of dead def? Cheers Thomson -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150101/ea39d1e4/attachment.html>

Hello all, I am a LLVM newer who want to add a new backend(EBC) into LLVM. After coping the related files from another target and modifying it, I meet a problem when I build the project. The error message is as follows: ================================================================ [ 94%] Built target llvm-dis Linking CXX executable ../../bin/llvm-mc Undefined symbols:

We are currently doing something similar to your third option in Hexagon backend. But it is a VLIW so predication is not the only reason for that. Sergei --- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation > -----Original Message----- > From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] > On Behalf Of Marcello

On Fri, Oct 19, 2012 at 04:38:29PM +0100, Marcello Maggioni wrote: > Hello, > I'm working on a compiler based on LLVM for a SIMD architecture that > supports instruction predication. We would like to implement > branching on this architecture using predication. > As you know the LLVM-IR doesn't support instruction predication, so > I'm not exactly sure on what is the

Hi, I've done work on predicated SIMD representations for LLVM. If you search through the archives, you may find my "applymask" proposal, which is an attempt at representing predication in a very comprehensive way. I've since stopped pushing the proposal in part because Larrabee's changing fortunes led to a decline of interest at the time, in part because the proposal

Hello, I'm working on a compiler based on LLVM for a SIMD architecture that supports instruction predication. We would like to implement branching on this architecture using predication. As you know the LLVM-IR doesn't support instruction predication, so I'm not exactly sure on what is the best way to implement it. We came up with some ways to do it in LLVM: - Do not add any

I am running into a problem when I turn on post-RA scheduler with mode "ANTIDEP_CRITICAL" for mips. I'd appreciate if someone could explain what is going wrong here. This is the basic block before post RA scheduling (at PostRASchedulerList.cpp:322): *(gdb) #3 0x0000000000ed3d26 in runOnMachineFunction (this=0x20aa470, Fn=...) at lib/CodeGen/PostRASchedulerList.cpp:322 322

Hi, while using this function I noticed that Type::getScalarSizeInBits() is not marked as const even if inside its body it just uses only other "const" functions and types. This prevents the usage of the function through const pointers/references to Type without any apparent reason. I propose of marking the function as const. (attached is a patch that does so). Cheers, Marcello --

Hi Verena, Windows + MachO is likely to run into lots of problems once you start passing in non-trivial code. The relocation model is very tied to Darwin. I believe some folks doing JIT on Windows have had some success w/ ELF. Hopefully someone more familiar with the specifics of that will chime in. -Jim On Jun 29, 2012, at 8:58 AM, Verena Beckham <verena at codeplay.com> wrote: >

Hi All, I have a question about TableGen RegisterClass definition. I need to map different size of MVTs into a register class as below. def TestReg : RegisterClass<"Test", [v8i32, v4i32], ...> When I look at TableGen and CodeGen, it looks the types are used as following: 1. MCRegisterClass's RegSize and Alignment 2. SpillSize in TableGen 3. Type constraint for instruction

Hi, anyone know anything about copy propagation? Matthias, I see this was your code originally? Was there some assumptions you made? I'm hitting an assertion in MachineCopyPropagation::isNopCopy: if (Src == PreviousSrc) { assert(Def == PreviousDef); return true; } This code compares two COPY instruction to see whether they are effectively "the same". The assert assumes

Hi, The LLVM lang ref (http://llvm.org/docs/LangRef.html#i_bitcast) notes that bitcast of vectors to vectors is OK, provided the vectors are of the same size. In attempting this on large vector types (e.g. 16xi64 -> 16xf64), I get assertions related to Extended Value Types when attempting to perform code generation, but no errors at the BC level. Is it simply unsupported to stray outwith

Hello, In our LLVM backend we needto output certain labels in the AsmPrinter in order to access certain data through those labels. These labels are related to BlockAddress objects (that come from above) and they should be put into a position that is related to the BasicBlock pointed by that BlockAddress. The problem I'm hitting is that if the BasicBlock that the BlockAddress points to

Hi, I'm getting an Instruction emitter crash when emitting an INLINEASM SDNode that is Glued to other nodes. The crash happens at line 808 of file llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp: const MCInstrDesc &MCID = TII->get(F->getMachineOpcode()); with the assertion: assert(isMachineOpcode() && "Not a MachineInstr opcode!"); I'm not a great expert

Hi, In X86MachObjectWriter::RecordX86Relocation I found the comment if (Target.isAbsolute()) { // constant // SymbolNum of 0 indicates the absolute section. // // FIXME: Currently, these are never generated (see code below). I cannot // find a case where they are actually emitted. Type = macho::RIT_Vanilla; } Is the FIXME still true? I've got some code that

Hi Jim, Andrew, Thanks, I read the discussions about using ELF + MCJIT + Windows and was hoping MachO would work just as well. Since you don't need to modify LLVM to be able to output MachO this was my first choice. But are you saying MachO will not work as well as ELF? Thanks for the patch Andrew, that will have to be my plan B in this case. Verena On 29/06/2012 23:47, Kaylor, Andrew

Hi, I noticed that a while ago the isSSA flag was removed from MIR, and this property is now computed. However, the deduction only checks the virtual registers (whether they are assigned to more than once). Now I have MIR tests which live after RA, so they only contain physical registers, so the parser determines they are in SSA form. These tests now fail because some of our passes can be

Hi, I found that prologue_end markers where badly placed in my test, and applied https://reviews.llvm.org/D41762 in the hope that it would fix it (I'm on 4.0.1). However, this fix doesn't work for VLIW architectures. At this point we're iterating over bundles, not MachineInstructions, and the FrameSetup flag is set on MachineInstructions, not bundles. If bundling happens in the

Hi, I think there might be a bug in the tail duplicator (called from MachineBlockPlacement in my case), when duplicating a block that contains an implicit fall-through. Suppose you have the following blocks BB#1: Predecessors according to CFG: BB#2 ... conditional_branch <BB#3> < implicit fall-through to BB#2 > Successors according to CFG: BB#2 BB#3 BB#2:

On May 9, 2013, at 4:02 AM, Fraser Cormack <fraser at codeplay.com> wrote: > I have an instruction that takes no operands, and produces two results, in two consecutive cycles. > > I tried both of the following to my Schedule.td file: > > InstrItinData<IIMyInstr, [InstrStage<2, [FuncU]>], [1, 2]>, > InstrItinData<IIMyInstr, [InstrStage<1,