similar to: How to constraint instructions reordering from patterns?

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. > >

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,

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;

Hello. I'm having problems at instruction selection with my back end with the following basic-block due to a vector add with immediate constant vector (obtained by vectorizing a simple C program doing vector sum map): vector.ph: ; preds = %vector.memcheck50 %.splatinsert = insertelement <8 x i64> undef, i64 %i.07.unr, i32 0

But isn't kinda silly that we transform to xor and then we transform it back. What is the advantage in doing so? Also, since we do that method, I now have to introduce setcc patterns for i1 values, instead of being able to just use logical pattern operators like not. -Dilan On Fri, Jul 21, 2017 at 11:00 AM Dilan Manatunga <manatunga at gmail.com> wrote: > For some reason I

Hi, I am having some issues with how some of the instructions are being legalized. So this is my intial basic block. The area of concern is the last three instructions. I will pick and choose debug output to keep this small. SelectionDAG has 36 nodes: t0: ch = EntryToken t6: i32,ch = CopyFromReg t0, Register:i32 %vreg507 t2: i32,ch = CopyFromReg t0, Register:i32 %vreg17

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'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

Hi all, Our target does not have native support for 64-bit integers, so we rely on library calls for certain operations (like sdiv). We recently ran into a problem where these operations that are expanded to library calls aren't maintaining the proper ordering in relation to other chains in the DAG. The following snippet of a DAG demonstrates the problem. t0: ch = EntryToken t2:

Here's our testcase: #include <stdio.h> struct flags { unsigned frog: 1; unsigned foo : 1; unsigned bar : 1; unsigned bat : 1; unsigned baz : 1; unsigned bam : 1; }; int main() { struct flags flags; flags.bar = 1; flags.foo = 1; if (flags.foo == 1) { printf("Pass\n"); return 0; } else {

On 12/21/2016 4:45 PM, Phil Tomson via llvm-dev wrote: > Here's our testcase: > > #include <stdio.h> > > struct flags { > unsigned frog: 1; > unsigned foo : 1; > unsigned bar : 1; > unsigned bat : 1; > unsigned baz : 1; > unsigned bam : 1; > }; > > int main() { > struct flags flags; > flags.bar = 1; >

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,

Hello, I've hit an assertion in SelectionDAG where we try to merge 2 loads that have the same operands but their MMO flags differ. One is dereferenceable and one is not. I'm not sure what the underlying issue here is: 1) MDSDNode with the same operands should have the same flags set on their respective MMO. The fact the flags differ when the opcode,types,operands and address-space are

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),

Have you read http://llvm.org/docs/WritingAnLLVMBackend.html and http://llvm.org/docs/CodeGenerator.html ? http://llvm.org/docs/WritingAnLLVMBackend.html#instruction-selector describes how to define a store instruction. -Eli On 7/6/2017 6:51 PM, hameeza ahmed via llvm-dev wrote: > Please correct me i m stuck at this point. > > On Jul 6, 2017 5:18 PM, "hameeza ahmed"

Hello, i am experimenting with the increase in register/ vector width to 64 elements of 32 bits instead of 16 in x86 backend. for eg. i have a loop with 65 iterations; if my IR generates v64i32 and 1 scalar, still the backend breaks the v64i32 into 4 v16i32. i want it to retain v64i32. like if there are 128 elements in loop then it should break it into 2 v64i32 instructions. in order to do this i

Hello everyone, I wanted to attach a node without affecting the present nodes in any way. I tried to use MVT::Glue for that but I think I'm missing something as I could not achieve the below state. LUI LUI | | ADDI ----GLUE---- ADDI | store I've few question about this and Glue node in general, I'll be happy to get some help on

Hi there, I try to JIT compile some bitcode and seeing the following error: LLVM ERROR: Cannot select: 0x28ec830: ch,glue = X86ISD::CALL 0x28ec7c0, 0x28ef900, Register:i32 %EDI, Register:i8 %AL, RegisterMask:Untyped, 0x28ec7c0:1 0x28ef900: i32 = X86ISD::Wrapper TargetGlobalAddress:i32<void (i8*, ...)* @_ZN5FooBr7xprintfEPKcz> 0 0x28ec520: i32 = TargetGlobalAddress<void (i8*, ...)*

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;

Thank You. On Fri, Jul 7, 2017 at 10:03 AM, Craig Topper <craig.topper at gmail.com> wrote: > Yes, that error is from instruction selection. I think your legalization > changes worked fine. > > ~Craig > > On Thu, Jul 6, 2017 at 8:21 PM, hameeza ahmed via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> also i further run the following command;