similar to: Inlining + CSE + restrict pointers == funtimes

At a high level, EarlyCSE should be intersecting the metadata of instructions that it combines. If it doesn't, and also doesn't drop the metadata, that seems like a bug, regardless of anything else. On 1/22/20 9:30 AM, Jeroen Dobbelaere wrote: Hi Neil, Hall, - as far as 'C' is concerned, this is input code is valid, as the pointers are not used to modify objects. - as far as

Dear all, Hi! Recently, I notice a situation where I cannot infer the size of the outermost dimension of array in the function interface. To concretely depict the problem, I show the C source code and the generated IR code at the end. The array size of A[] is 51 but this information is lost in the generated IR. How can I maintain such information in IR? Should I set some argument for

Dear David, Thanks for your prompt reply! Sure, I can implement a AST visitor to go through the AST to get the information but I just wonder whether there is any other way to let Clang do so. What I am considering is how to let the generated IR looks like below, which some tools realize: define dso_local i32 @_Z1fPii([51 x i32]* %A, i32 %x) local_unnamed_addr #0 !dbg !7 { entry: ...

Hi, I am observing a strange behaviour in which Clang ignores __restirct when I include some standard headers. For example, this code: void vec_add(int* __restrict a, int* __restrict b, int n) { #pragma unroll 4 for(int i=0; i<n; ++i) { a[i] += b[i]; } } results in: ; Function Attrs: nofree norecurse nounwind define dso_local void @_Z7vec_addPiS_i(i32*

Johannes, Thanks, I have been following along some of the thread(s) and the phab reviews. The scope of this work is more encompassing than our current needs and I've looked at trying to carve a piece out. It's not clear to me what purpose the llvm.noalias intrinsic serves right now. Also, if a mem instruction has !noalias metadata, then it should not be aliased, but I must be missing

Hi, I am trying to understand how assume shaped arrays are received and processed in LLVM IR. I am using "flang" for my front end. There seems to be an array descriptor received as implicit argument for every assume shaped array. For my test routine: ---snip-- SUBROUTINE test(a,b,Li,Lj,Istr,Iend,Jstr,Jend) INTEGER, INTENT(IN) :: Li,Lj INTEGER, INTENT(IN) :: Istr, Iend,

Ok I think we have some common ground - CSE should choose the aliased pointer over the non-aliased one because we don't want the no-aliasing information to creep outwards from the inlined callsite. I'll put together a patch in the coming days and add y'all as reviewers so you get visibility. Cheers, -Neil. On Wed, Jan 22, 2020 at 4:47 PM Jeroen Dobbelaere < Jeroen.Dobbelaere at

For the following C code __fp16 x, y, z, w; void foo() { x = y + z; x = x + w; } clang produces IR that extends each operand to float and then truncates to half before assigning to x. Like this define dso_local void @foo() #0 !dbg !18 { %1 = load half, half* @y, align 2, !dbg !21 %2 = fpext half %1 to float, !dbg !21 %3 = load half, half* @z, align 2, !dbg !22 %4 = fpext half %3 to float, !dbg

----- Original Message ----- > From: "Hal Finkel" <hfinkel at anl.gov> > To: "Chandler Carruth" <chandlerc at google.com> > Cc: llvmdev at cs.uiuc.edu > Sent: Thursday, July 16, 2015 1:58:02 AM > Subject: Re: [LLVMdev] Improving loop vectorizer support for loops > with a volatile iteration variable > ----- Original Message ----- > >

[AMD Official Use Only - Internal Distribution Only] Hi, Following issue is observed with Type Based Alias Analysis(TBAA). ####################################################### struct P { float f1; float f2; float f3[3]; float f4; }; void foo(struct P* p1, struct P* p2) { p1->f2 = 1.2; p2->f1 = 3.7; } int callFoo() { struct P p; foo(&p, &(p.f2)); }

On Thu, Dec 8, 2011 at 2:11 PM, Vitor Luis Menezes <vitor at utexas.edu> wrote: > We've got the following test case: > > > class A { > public: >   int x; >   A(int x) : x(x) {} >   int hoo() {return 4;} >   virtual int foo() {return x;} >   virtual int goo() {return foo()+10;} >   virtual int operator+(A &a) { >     return x + a.x; >   } > };

Thanks Eli. I forgot to bring up the strict FP questions which I was working on when I found this. If we're in a strict FP function, do the fp_to_f16/f16_to_fp emitted by promoting load/store/bitcast need to be strict versions of fp_to_f16/f16_to_fp. And if so where do we get the chain, especially for the bitcast case which isn't a chained node. ~Craig On Tue, Dec 10, 2019 at 3:18 PM

Hello, I believe these descriptors are specific to flang, not to LLVM. You should probably ask your question on flang-dev list. Thank you, --Eugene From: llvm-dev [mailto:llvm-dev-bounces at lists.llvm.org] On Behalf Of Venkataramanan Kumar via llvm-dev Sent: Wednesday, April 25, 2018 8:44 AM To: llvm-dev at lists.llvm.org Subject: [llvm-dev] Help on understanding assume shape array

We've got the following test case: class A { public: int x; A(int x) : x(x) {} int hoo() {return 4;} virtual int foo() {return x;} virtual int goo() {return foo()+10;} virtual int operator+(A &a) { return x + a.x; } }; class B : public A { public: B(int x) : A(x) {} int hoo() {return 2;} virtual int foo() {return A::foo()*2;} }; int main() { A* a = new A(1);

Hi Gerolf, I think we have several (perhaps separable) issues here: 1. Do we have a canonical form for loops, preserved through the optimizer, that allows naturally-constructed loop nests to remain separable? 2. Do we forbid non-lowering transformations that turn vectorizable loops into non-vectorizable loops? 3. How do we detect cases where transformations cause a negative answer to either

I have a global 2-D array ARRAY[N][M] and I am accessing it inside the for loop like this: for (i...) for (j ...) ARRAY[i][j] ... So nothing really weird is happening. If I look at the generated IR, it is also fairly straight forward. @ARRAY0 = dso_local global [32 x [32 x i32]] zeroinitializer, section ".slow_mem", align 32, !dbg !84 ... %45 = getelementptr inbounds [32 x [32 x

----- Original Message ----- > From: "Elena Demikhovsky" <elena.demikhovsky at intel.com> > To: "Hal J. Finkel" <hfinkel at anl.gov>, "Eli Friedman" > <eli.friedman at gmail.com> > Cc: "llvm-dev" <llvm-dev at lists.llvm.org>, "Richard Smith" > <richard-llvm at metafoo.co.uk> > Sent: Tuesday, July 26,

Hello all, Our compilers class has been using LLVM, and a partner and I decided to implement devirtualization of virtual C++ calls in LLVM as a class project. We quickly realized that existing debug metadata generated by Clang didn't give us enough info to (precisely) implement this, and as such have already begun modifying Clang to insert such metadata. However, for devirtualization we also

TBAA Question. Please consider the following test case. ---Snip-- struct B { int b1; int b2; }; struct C { int b1; }; struct A { int a1; struct C SC; int a2; }; int foo1(struct A * Aptr, struct B* Bptr) { int *a = &Aptr->SC.b1; *a=10; Bptr->b1 = 11; return *a; } int foo2(struct A * Aptr, struct B* Bptr) { Aptr->SC.b1=10; Bptr->b1 = 11; return

Hi, I'm trying to abstract some special pointers with a class, like in the example program below: 1 #define __remote __attribute__((address_space(1))) 2 #include <stdint.h> 3 4 __remote int* A; 5 __remote int* B; 6 7 class RemotePtr { 8 private: 9 __remote int* __restrict a; 10 11 public: 12 RemotePtr(__remote int* a) : a(a) {} 13 14 __remote