similar to: [LLVMdev] llvm-mc and endianess.

Hi, For the development of a new micro-controller backend, I try to lowering the following store SDNode: t5: ch = store<ST2[%ptr2](align=4)> t0, Constant:i16<3>, FrameIndex:i16<1>, undef:i16 I have defined the following instruction and associated DAG pattern. def MOVSUTO_A_i32o : CLPFPU_A_i32o_Inst<0b1000001101,

Hi, I'm writing a backend for a proprietary microcontroller. I'm facing a limitation related to Live Interval Analysis. Some FPU instructions, most notably the FDIV, requires a few cycles to complete. There is a pipeline and, during the execution of the FDIV, others instructions could be executed in parallel, provided they don't use the same registers. This pipeline has been modeled

Hi again, After further investigation, I've found that the private PhysRegUseDefLists array ("head of use/def list for physical register") from MachineRegisterInfo class seems to be empty. But I didn't found any methods for updating such data structure. How/where this "use/def list" should be managed ? Is the documentation

Hi, In the context of MachineCode custom inserter, I'm trying to enforce the mapping of virtual register to a physical one. According to the documentation https://llvm.org/docs/CodeGenerator.html#mapping-virtual-registers-to-physical-registers There are two ways: the direct one and the indirect ones. The indirect ones refer VirtRegMap class that I've never found. So I tried the direct

Hi, I'm trying to complete the lowering for a new microcontroller. I'm using LLVM 3.8. For now this lowering crashes on 'Store' node, which is actually not yet defined. I've tried to map the ISel 'Store' node to architecture specific instructions. I've define the following semantic to my architecture specific instructions: def MOVSUTO_SU_rr :

Hi, I have a question related to pre-RA scheduling and spill of registers. I'm writing a backend for two operands instructions set, so FPU operations result have implicit destination. For example, the result of FMUL_A_oo is implicitly the register FA_ROUTMUL. I have defined FPUaROUTMULRegisterClass containing only FA_ROUTMUL. During the instruction lowering, in order to avoid frequent spill

Hi, I've some problems/questions while implementing the BUILD_VECTOR primitive for a SIMD microcontroller... This microcontroller has two FPU units: UnitA and UnitB. UnitA has a bank of 512 registers named RegisterA_0 .. RegisterA_511. UnitB has a bank of 512 registers named RegisterB_0 .. RegisterB_511. The FPU instruction format has a 2 bits operand indicating which units are involved:

Hi, I'm try to lower the store LLVM-IR instruction as per the following LLVM IR program: *** IR Dump After Module Verifier *** define void @storeloadi32() { %ptr = alloca i32 store volatile i32 12, i32* %ptr ret void } The target instruction is associated to the store like this: def MOVSUTO_A_iSLr : CLPFPU_A_iSLr<0b1000001101,

Hi, I've instruction scheduling problem that I cannot further investigate by myself... Could someone give me some clues? After Instruction selection, here is part of the generated instruction. NOP MOV_AB_ro @s1, %fab_roff0 %6:fpuaoffsetclass = COPY %fab_roff0; FPUaOffsetClass:%6 MOV_A_oo %6, def %5; FPUaOffsetClass:%6,%5 MOVSUTO_A_iSLo 24575, def %7;

Hi, Is there a kind of scope mechanism in the instruction lowering pattern language in order to control where instructions are inserted or how they are later reordered during the SelectionDiag linearization? I know the glue chain that stick instructions together. But such mechanism in not provided in instruction lowering pattern. I'm facing many situations where some patterns are lowered into

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

The DAG dumping will try to print some of the nodes "inline" (i.e. where they are used) to make the output more readable, so the dump of the DAG may not strictly reflect the node ordering. -Krzysztof On 5/4/2018 8:18 AM, Dominique Torette via llvm-dev wrote: > Here is a last example to illustrate my concern. > > The problem is about the lowering of node t13. > >

Hi, I'm implementing the built_vector as an IMPLICIT_DEF followed by INSERT_SUBREGs. This approach is the one of the SPARC architecture. def : Pat<(build_vector (f32 fpimm:$a1), (f32 fpimm:$a2)), (INSERT_SUBREG(INSERT_SUBREG (v2f32 (IMPLICIT_DEF)), (i32 (COPY_TO_REGCLASS (MOVSUTO_A_iSLo (bitcast_fpimm_to_i32 f32:$a1)), FPUaOffsetClass)), A_UNIT_PART),

Krzysztof, Thanks for your interest to my questions. In order to clarify the context, here is the C source file of my test case. The 3 builtins initialize some stack pointers. They have to be executed before any other instruction. extern float fdivfaddfmul_a(float a, float b, float c, float d); volatile static float x1,x2,x3,x4; void _start(void) { float res;

Hi Krzysztof, Thanks for your response. I was trying to map function input parameters to machine specific registers. My solution I found is based to the RegInfo.setSimpleHint() API. Here is the body of the parameters loop of TargetLowering::LowerFormalArguments VReg = RegInfo.createVirtualRegister(RC); RegInfo.setSimpleHint(VReg,CLP::FA_ROFF1+i);

Here is a last example to illustrate my concern. The problem is about the lowering of node t13. Initial selection DAG: BB#0 '_start:entry' SelectionDAG has 44 nodes: t11: i16 = Constant<0> t0: ch = EntryToken t3: ch = llvm.clp.set.rspa t0, TargetConstant:i16<392>, Constant:i32<64> t5: ch = llvm.clp.set.rspb t3,

Hi Dominique, From your description it is not really clear what you are trying to do here. It may be the case that the goal you are trying to accomplish can be better reached using a different approach. In general, optimizations don't try to assign physical registers, that's done by the register allocation passes. There are some cases when target-specific passes use physical

Hi, I'm trying to optimize the 'extract_vector_elt' for my SIMD microcontroller. The idea is, during DAG combination, to merge load/extract sequence into an architecture specific node. During Instruction Selection, this specific node will be target selected to an architecture specific instruction. By 'combination of DAG nodes' I understand 'replacing a set of DAG nodes by

On 4/12/2018 8:01 AM, Dominique Torette via llvm-dev wrote: > > But there is one small issue in the inference of RegisterClass of the > implicitly defined register. > > As shown below, the %vreg6<def> is implicitly defined as FPUabRegisterClass. > > This register class accepts the v2f32 type, but for others addressing > mode context this register should be

Proposal for ELF text and data big endian support for direct object generation Unless I am mistaken, currently big endian support in the MC layer for ELF direct object generation is limited to ELF headers and tables like relocations. Text and data section contents are still generated as individual bytes. It looks as if the effort was started, but never completed. The proposal is to extend the