similar to: Putting "tied-to" constraints on virtual registers in SelectionDAGISel's Select() method

Hi, I am experimenting with creating instructions that write into virtual registers that use the ARM GPRPair register class in Pre-RA phase. During register allocation, I hit an assertion because the code is not in SSA form: lib/CodeGen/MachineRegisterInfo.cpp:271: llvm::MachineInstr* llvm::MachineRegisterInfo::getVRegDef(unsigned int) const: Assertion `(I.atEnd() || llvm::next(I) ==

Ok, I've had time to track this down a little bit more and I seem to have found another case where it fails. This is occurring during Schedulur->EmitSchedule() in SelectionDAGISel.cpp:695. The problem seems to be that somehow the CopyToReg part of the switch statement in ScheduleDAG::EmitNode has a FrameIndex as its second operand. This is especially problematic because the code is either

Hello. Does anybody have an idea why I'm getting the error below when using llc with arguments -O1 -disable-cgp? Note that this error is not given when using llc -O0. (I'd like to mention also I'm using custom Instruction selection for BUILD_VECTOR, which gets converted in my back end's machine instrution VLOAD_D, although the custom code seems to always select

Hi again, I'm finally getting some time to work on my m68k backend again. :) I was trying to solve the problem that loads from arbitrary addresses need to go through address registers. 68k allows flexible addressing similar to what the x86 can do, only that the adressing base has to reside in an address register: move.size[b/w/l] <Displacement>(Ax, Dx * Scale[1/2/4/8]), <Dest>

Hi Matthias, Sorry for the late reply. Yes, you are correct, I do have optnone attribute on my function. I did pass -O0 to the tools. For your information, my invocations are as below: clang --target=mips-unknown-linux -mips32 test.c -emit-llvm -S llc -O0 -march=mips -mcpu=mips32 test.ll -o test.s Based on the generated .ll file, there is optnone attribute on the function, i

On Jul 1, 2009, at 2:22 PMPDT, Dan Gohman wrote: >> Ops.push_back(DAG.getConstant(1, MVT::i32)); >> Chain = DAG.getNode(ISD::ADD, DAG.getVTList(MVT::Other, MVT::i32), >> &Ops[0], Ops.size()); >> >> Isn't that the way how it is supposed to work? > > ADD does not use a chain, so there's no chain operand, or > MVT::Other result for it in an ADD

Hello. Because I experience optimizations (DCE, OoO schedule) which mess the correct semantics of the list of instructions lowered in ISelLowering from the VSELECT LLVM instruction, and these bad transformations happen even before scheduling, at later I-sel subpasses, I try to fix this problem by lowering VSELECT to only one pseudo-instruction and LATER translate it to a list of

On Jan 27, 2009, at 3:54 PM, Villmow, Micah wrote: > Ok, I've had time to track this down a little bit more and I seem to > have found another case where it fails. This is occurring during > Schedulur->EmitSchedule() in SelectionDAGISel.cpp:695. The problem > seems > to be that somehow the CopyToReg part of the switch statement in > ScheduleDAG::EmitNode has a

Hey, I wanted to add an intrinsics to read MSRs. So I added the intrinsics and lowered it to a new ISD node I created ISD::RDMSR, its first operand is the MSR id. I added a case in X86DAGToDAGISel::Select for ISD::RDMSR. Now I know rdmsr works like so: mov r/ecx, <id> rdmsr r/eax holds the lower 32/64 bit >From what I understood this needs a Token Factor node, nodes which are

Hi Guys, I have a taget instruction which take a vec4 and returns a vec4.( say instruction “vec4:$dst mod( vec4:$src)" ) And I want to use it to match i an ir instruction/intrinsic function( say " float:$dst llvm.irmod( vec4:$src)" which takes a vec4, output a float. I think the procedure is: when I see the intrinsic llvm.irmod, I need to call "extractlt(

2008/2/15, Andreas Fredriksson <deplinenoise at gmail.com>: > > I tried mocking this up using the following. (Base is what's returned as > the Ax in the move expression above when the DAG is constructed due to > SelectAddr().) > > SDOperand chain = CurDAG->getCopyToReg(Base, M68K::A3, Base); > Base = CurDAG->getCopyFromReg(chain, M68K::A3, MVT::i32);

Hi, I'm lowering some of the logical operators (by example the | operator) on integer32. Sadly my target only provide native instruction on high and low parts of 32 bits registers. So, I have to generate a sequence of two native instructions (LOR followed by HOR). I've introduced an Pseudo instruction with a custom inserter. def OR_A_oo : CLPPseudoInst<(ins

Thanks to your help I've actually made some progress... Especially the SelectionDAGNodes.h was a good hint. But there are still some things that I can't figure out: // 'mov eax, 41' Chain = DAG.getCopyToReg(Chain, DAG.getRegister(X86::EAX, MVT::i32), DAG.getConstant(41, MVT::i32), InFlag); InFlag = Chain.getValue(1); // 'inc eax' SDValue eaxVal =

Adding -debug to a -gen-dag-isel run can also print useful information about the parsed patterns. On Wed, Jul 15, 2020 at 10:44 AM Matt Arsenault via llvm-dev < llvm-dev at lists.llvm.org> wrote: > > > > On Jul 15, 2020, at 13:33, Rotate Right via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > > > Is there a backend to Tablegen which can dump a map of

Hi, I'm still having problems implementing my custom inserter in the X86 backend. I found a solution to my last problem (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/078296.html), by using a virtual register. The binary works when it's compiled in -O0, but not in -O1,-O2,... I really can't figure what I'm doing wrong... Any idea? Here is the code of my custom

Is there a backend to Tablegen which can dump a map of pattern-to-matched to instruction-to-be-generated? --help doesn't seem to indicate anything like that. On Tue, Jul 14, 2020 at 2:13 PM Rotate Right <rightrotate5 at gmail.com> wrote: > Thanks Matt and Thomas. I will go through them. > > On Tue, Jul 14, 2020, 1:35 PM Matt P. Dziubinski <matdzb at gmail.com> wrote:

Hi all, Can anyone give an idea to solve my problem? I'm implementing backend part using LLVM for my research architecture. The main issue is that this architecture cannot use stack/heap. So, all the value should be stored in the register. Given that architecture, load/store instruction in IR uses virtual register to load/ store the value. For example: C source code is: if(...) { a = 1;

Running llc with '-verify-machineinstrs' may tell you which instruction break the SSA form. Ruiling From: llvm-dev [mailto:llvm-dev-bounces at lists.llvm.org] On Behalf Of jin chuan see via llvm-dev Sent: Monday, September 11, 2017 10:02 AM To: Matthias Braun <mbraun at apple.com> Cc: llvm-dev at lists.llvm.org Subject: Re: [llvm-dev] Live Register Spilling Sorry about the

To get into more detail, I'm trying to update WebAssembly's `call` instruction. `call` is currently constrained to return one or zero arguments, so in TableGen we have a separate call Instruction for each possible return type. But I need to update calls to return arbitrarily many values of any combination of WebAssembly types, so even if we imposed some reasonable artificial limit like 8

What is the meaning of a $ sign in tablgen? Here is an example // Pattern fragments def vextract_sext_i8 : PatFrag<(ops node:$vec, node:$idx), (MipsVExtractSExt node:$vec, node:$idx, i8)>; Taken from https://github.com/llvm-mirror/llvm/blob/fd031a51c35d1781c066a42e221a7ae28610be3f/lib/Target/Mips/MipsMSAInstrInfo.td#L118 -- Rail Shafigulin