similar to: LLVM Backend Issues

Thanks Anton and Krzysztof! Here is the dump using the -debug flag. At this point I am not making much sense of this, would it be too much to ask if one of you could walk me through one of these lines? One thing that I didn't point out is that I never defined any separate floating point registers, not sure if this will pose any issue? Thanks again for your time! Jeff jeff at

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

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;

We've recently moved our project from LLVM 3.6 to LLVM 3.9. I noticed one of our code generation tests is breaking in 3.9. The test is: ; RUN: llc < %s -march=xstg | FileCheck %s define i64 @bclr64(i64 %a, i64 %b) nounwind readnone { entry: ; CHECK: bclr r1, r0, r1, 64 %sub = sub i64 %b, 1 %shl = shl i64 1, %sub %xor = xor i64 %shl, -1 %and = and i64 %a, %xor ret i64

Setting the ISD::ROTL to Expand doesn't work? (via SetOperation) You could also do a Custom hook if that's what you're looking for. On Thu, Nov 3, 2016 at 5:12 PM, Phil Tomson <phil.a.tomson at gmail.com> wrote: > ... or perhaps to rephrase: > > In 3.9 it seems to be doing a smaller combine much sooner, whereas in 3.6 > it deferred that till later in the

Is there any way to get it to delay this optimization where it goes from this: Initial selection DAG: BB#0 'bclr64:entry' SelectionDAG has 14 nodes: t0: ch = EntryToken t2: i64,ch = CopyFromReg t0, Register:i64 %vreg0 t4: i64,ch = CopyFromReg t0, Register:i64 %vreg1 t6: i64 = sub t4, Constant:i64<1> t7: i64 = shl Constant:i64<1>, t6

Hi All, I have a question about splitting 'EXTRACT_VECTOR_ELT' with 'v2i1'. I have a llvm IR code snippet as following: llvm IR code snippet: for.body: ; preds = %entry, %for.cond %i.022 = phi i32 [ 0, %entry ], [ %inc, %for.cond ] %0 = icmp ne <2 x i32> %vecinit1, <i32 0, i32 -23> %1 = extractelement <2 x i1>

One option may be to prevent the formation of ROTL, if possible, and then generating rol by hand. Marking it as "expand" would likely stop the DAG combiner from creating it. Then you could "preprocess" the selection DAG before the instruction selection and do the pattern matching yourself. -Krzysztof On 11/3/2016 4:24 PM, Phil Tomson via llvm-dev wrote: > I could try

> extends the elements to 8bit and stores them on stack. Store is responsible for zero-extend. This is the policy... - Elena -----Original Message----- From: jingu at codeplay.com [mailto:jingu at codeplay.com] Sent: Friday, September 15, 2017 17:45 To: llvm-dev at lists.llvm.org; Demikhovsky, Elena <elena.demikhovsky at intel.com>; daniel_l_sanders at apple.com Subject: Re: Question

I have the following selection DAG: SelectionDAG has 9 nodes: t0: ch = EntryToken t2: i64,ch = CopyFromReg t0, Register:i64 %vreg0 t16: i32,ch = load<LD1[%ptr](tbaa=<0x10023c9f448>), anyext from i8> t0, t2, undef:i64 t15: v16i8 = BUILD_VECTOR t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16 t11: ch,glue = CopyToReg t0, Register:v16i8 %V2, t15

Please open a bugzilla ticket and attach your testcase. It will allow us to debug and fix the problem. Thanks - Elena From: JinGu [mailto:jingu at codeplay.com] Sent: Saturday, September 16, 2017 00:38 To: Demikhovsky, Elena <elena.demikhovsky at intel.com>; daniel_l_sanders at apple.com <daniel_l_sanders at apple.com>; Jon Chesterfield <jonathanchesterfield at

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

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:

Hi List, I have start and end times of events structure(list(start = c("15:00", "15:00", "15:00", "11:00", "14:00", "14:00", "15:00", "12:00", "12:00", "12:00", "12:00", "12:00", "12:00", "12:00", "12:00", "12:00", "12:00",

> so I think we need to use non-extending load for element size less than 8bit on "DAGTypeLegalizer::SplitVecOp_EXTRACT_VECTOR_ELT" like this roughly. > if (N->getOperand(0).getValueType().getVectorElementType().getSizeInBits() < 8) { > return DAG.getLoad(N->getValueType(0), dl, Store, StackPtr, MachinePointerInfo()); > } else { > return

Hello, LLVM devs. I'm compiling the following simple IR: define dso_local i32 @main(i32 %argc, i8** %argv) { entry: %retval = alloca i32, align 4 %argc.addr = alloca i32, align 4 %argv.addr = alloca i8**, align 8 store i32 0, i32* %retval, align 4 store i32 %argc, i32* %argc.addr, align 4 store i8** %argv, i8*** %argv.addr, align 8 ret i32 0 } using `llc -march=sparc

On Tue, 18 Dec 2018 at 07:11, Gleb Popov via llvm-dev <llvm-dev at lists.llvm.org> wrote: > However, I haven't managed to get a "Constant<>" in the DAG when compiling for X86. I'm interested in how it is lowered. Can you please give me some guidance on this? How are you looking? When I run "llc -mtriple=x86_64-linux-gnu -debug-only=isel" on your IR I get

int %nlz10(uint %param.x) { %.t3 = shr uint %param.x, ubyte 1 ; <uint> [#uses=1] %.t4 = or uint %.t3, %param.x ; <uint> [#uses=2] %.t7 = shr uint %.t4, ubyte 2 ; <uint> [#uses=1] %.t8 = or uint %.t7, %.t4 ; <uint> [#uses=2] %.t11 = shr uint %.t8, ubyte 4 ; <uint> [#uses=1]