similar to: [LLVMdev] More address registers

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);

Dan Gohman wrote: > There certainly are wishlist items for TableGen and TableGen-based > instruction descriptions, though I don't know of an official list. > Offhand, > a few things that come to mind are the ability to handle nodes with > multiple results, Is there an official workaround, BTW? - Volodya

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

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

On Sep 9, 2010, at 12:59 PM, Borja Ferrer wrote: > Hello, i've noticed a new possible missed optimization while testing more trivial code. > This time it's not a with a xor but with a multiplication instruction and the example is little bit more involved. > > C code: > > typedef short t; > t foo(t a, t b) > { > t a4 = a*b; > return a4; > } >

Thanks, that sounds like it would work. Was this based on what any other target did? Or do any other targets take this approach? I just want to make sure that we don't already have a hook suitable for this. Overriding runOnFunction to run what could be described as just a "late SelectionDAG pass" sounds pretty intrusive. Do you remember other approaches that didn't work? --

I am currently working on DAGToDAGISel class for MIPS and am trying to figure out a way to use INTRINSIC_W_CHAIN for an intrinsic which can return a value. My intrinsic is defined as: Intrinsic<[llvm_i32_ty],[llvm_i32_ty,llvm_i32_ty,llvm_i32_ty,llvm_i32_ty],[IntrReadWriteArgMem]>; i.e. it has four arguments and one return value In DAGToDAGISel when I try to pass it with four arguments and

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 =

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;

Hi Tim, Tim Northover-2 wrote > The code used for DIV is around X86ISelDAGToDAG.cpp:2415, but from a > glance the key points seem to be: > 1. use the second result of getCopyToReg (i.e. SDValue(setIdNode, 1)) > in the RDMSR node. > 2. Give your RDMSR node type MVT::Glue instead of MVT::Other I tried doing what you said, and the DAG looks like how I think it supposed to look like

Hello, i've noticed a new possible missed optimization while testing more trivial code. This time it's not a with a xor but with a multiplication instruction and the example is little bit more involved. C code: typedef short t; t foo(t a, t b) { t a4 = a*b; return a4; } argument "a" is passed in R15:R14, argument "b" in R13:R12, the return value is stored in

Hello everybody, hi Evan, this patch changes the lowering of arguments for tail call optimized calls. Before arguments that could be overwritten by each other were explicitly lowered to a stack slot, not giving the register allocator a chance to optimize. Now a sequence of copyto/copyfrom virtual registers ensures that arguments are loaded in (virtual) registers before they are lowered to the

Hi, I am writing a backend and having issues with properly lowering the result of getElementPtr ( specifically the add node that it generates). If we take this IR: %struct.rectangle = type { i24, i24 } ; Function Attrs: nounwind readonly define i24 @area(%struct.rectangle* nocapture readonly %r) #0 { entry: %width = getelementptr inbounds %struct.rectangle* %r, i16 0, i32 0 %0 = load i24*

On 3 December 2012 10:42, Mayur Pandey <mayurthebond at gmail.com> wrote: > So this seems to be the cause of the problem. I guess you're mixing two different problems. First, is the possible lack of conformance with the ABI you state, which I can't comment since I don't know that ABI very well. Second, is the fact that clang is not printing correct debug information (or is

I'm trying to write a store pattern that accepts both i32 and f32, however, when tablegen generates the code, it only generates the code for i32 only. def ADDR : ComplexPattern<i32, 2, "SelectADDR", [], []>; def MEM : Operand<i32> { let PrintMethod = "printMemOperand"; let MIOperandInfo = (ops GPR, GPR); } def global_st :

Hi Steve, Thanks for the tip regarding MIOperandInfo, I didn't think of that part of the tablegen description. Sadly, I did actually mean: r1 = *(i0 += m0). So increment i0 by m0. Read memory the memory location "pointed" to by i0. Store in r1. Sadly I am not too familiar with compiler terminology, so I don't know if there is a proper term for such a load. On Thu, Oct 23,

On Jul 13, 2009, at 10:02 AM, David Greene wrote: >>> - Tag instructons with source line information (customers really >>> want this). >> >> Right, that would be nice. This should be synthesizable from the >> DebugLoc on the instruction in the asm printer, no need to >> redundantly >> encode it into the comment field. > > Except the DebugLoc

On Sep 23, 2008, at 10:44 AM, Villmow, Micah wrote: > I’m trying to write a store pattern that accepts both i32 and f32, > however, when tablegen generates the code, it only generates the > code for i32 only. > > def ADDR : ComplexPattern<i32, 2, "SelectADDR", [], []>; > def MEM : Operand<i32> { > let PrintMethod = "printMemOperand";

----- Original Message ----- > From: "Bruce Hoult" <bruce at hoult.org> > To: "Johnny Val" <johnnydval at gmail.com> > Cc: "<llvmdev at cs.uiuc.edu>" <llvmdev at cs.uiuc.edu> > Sent: Thursday, October 23, 2014 8:31:35 AM > Subject: Re: [LLVMdev] Question regarding getElementPtr/Addressing modes in backend > > Many CPU

Hello all, I am working on adding atomics support to the AVR backend. Because the target can only have one core, it is sufficient to: - Save the status register - Disable interrupts - Do the nonatomic LOAD/STORE/SWAP/ADD - Restore the status register I’d really like to be able to do this at the IR level. What I want to do is write a custom lowering hook to convert ISD::ATOMIC_LOAD