similar to: [LLVMdev] Question on sret

On Wed, Jul 14, 2010 at 8:49 AM, John Criswell <criswell at uiuc.edu> wrote: > Dear All, > > What is the purpose of the sret function parameter attribute?  Does it > affect the calling convention used during code generation, is it a hint > to optimizations, or is it used for something else? Both of the above; see LangRef. > I'm currently working on automatic pool

On Fri, Aug 12, 2011 at 1:11 AM, Damien Gleizes <gleizesd at gmail.com> wrote: > > Hi all, > > I am trying to generate LLVM IR that calls an external C++ function > returning a structure by copy: > vec3 vec3::Cross(const vec3& iV) const; > > Here is the LLVM IR that I am generating for win32 ABI, which says that the > first parameter should be a pointer to the

On Wed, Oct 07, 2015 at 04:35:10PM -0700, Tim Northover wrote: > > That seems to make it a pretty good case for consider sret mandatory in > > general. > > (Still) no more than any other type cast IMO. If you know what you're > doing you can cast function pointers (at the LLVM level), otherwise > you're going to get into trouble. I think we are talking about two

Hi all, I am trying to generate LLVM IR that calls an external C++ function returning a structure by copy: vec3 vec3::Cross(const vec3& iV) const; Here is the LLVM IR that I am generating for win32 ABI, which says that the first parameter should be a pointer to the return value: %vec3 = type <{ float, float, float }> define void @CPP_Return_Struct(%vec3* %v1, %vec3* %v2) inlinehint

I am needing to return i128 as a shadow return due to abi issues on alpha.  The problem I am running into is the code for doing that with scalars (currently only used for vectors, as far as I can tell) sets the sret on the parameter.  If I just go this path, then I am setting sret on an integer pointer, which verify objects too.  LangRef doesn't say scalars are allowed to have sret set, but

Hi all, I'm currently building a DSL for a computer graphics project that is not unlike NVIDIA's Cg. I have an intrinsic with the following signature float4 sample(texture tex, float2 coords); that is translated to this LLVM IR code: declare void @"sample"(%float4* noalias nocapture sret, %texture, $float2) nounwind readnone The type float4 is basically an array of four

On Aug 19, 2010, at 1:38 PM, Andrew Lenharth wrote: > I am needing to return i128 as a shadow return due to abi issues on > alpha. The problem I am running into is the code for doing that with > scalars (currently only used for vectors, as far as I can tell) sets > the sret on the parameter. If I just go this path, then I am setting > sret on an integer pointer, which verify

Hi, all When I compile the C code containing the next statement to LLVM, *struct A const o = func(...);* I got the next corresponding LLVM bytecode *call void @func(%struct.A* noalias sret %o, ...)* Could you tell me why function "func" with a return value is changed to be one with a void return value and another more parameter %o. Does "noalias sret" play a special role?

On Oct 6, 2015, at 4:33 PM, Reid Kleckner via llvm-dev <llvm-dev at lists.llvm.org> wrote: > On Tue, Oct 6, 2015 at 1:21 PM, Joerg Sonnenberger via llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: > Can you give an example of where it would trigger in LTO and when should > not? > > You could imagine that __muldc3 might be

Hi all, in Rust we have a bug report about about a missed optimization which one would expect CallSlot optimization to handle: https://github.com/rust-lang/rust/issues/48533 The IR looks like this: define void @bar(%S* noalias nocapture sret dereferenceable(16), void (%S*)* nocapture nonnull) unnamed_addr #0 { %3 = alloca %S, align 8 %4 = bitcast %S* %3 to i8* call void

Let's go directly to the example struct S { double dummy1; double dummy2; }; S bar(); S foo() { return bar(); } This is the result of g++ -c -S -O2 (focus on the final `ret'): __Z3foov: LFB0: pushl %ebp LCFI0: movl %esp, %ebp LCFI1: pushl %ebx LCFI2: subl $20, %esp LCFI3: movl 8(%ebp), %ebx movl %ebx, (%esp) call __Z3barv pushl %eax movl %ebx, %eax movl -4(%ebp), %ebx

On Fri, Sep 25, 2009 at 2:41 PM, Óscar Fuentes <ofv at wanadoo.es> wrote: > I filed a bug yesterday ( http://llvm.org/bugs/show_bug.cgi?id=5046 ) > and Anton kindly explained that LLVM is doing the right thing as per the > ABI (the GCC ABI, I'll add). > >  1. Is there a LLVM way of dealing with this without using separate code >  for VC++ and GCC? I'm not sure what

Hi, After removing support for the i64 type in the *CallingConv.td, sret-demotion is performed and we now have a store<(store 8, align 1)> DAG node being generated. Please refer to the attached dag_funcret.pdf DAG visualization. My understanding is that, the second operand(CopyFromReg->Register %1, Register %0 back-up) in the store node is the memory location allocated for the i64 type

Hi llvm-dev, >> The CopyFromReg->CopyToReg->CopyFromReg sequence doesn’t have the chains set correctly: the second CopyFromReg’s input chain isn’t connected to the CopyToReg’s output chain. (This appears to be the same problem in both graphs.) The DAG mentioned was generated by the SelectionDAGBuilder and as much as possible, we only modify the files within our target so I tried

On Mon, Oct 05, 2015 at 03:45:29PM -0700, Reid Kleckner wrote: > > > On 3 October 2015 at 02:29, Joerg Sonnenberger via llvm-dev > > > <llvm-dev at lists.llvm.org> wrote: > > > > while debugging assertions when building libm for 32bit Sparc, I hit > > the > > > > following IR: > > > > > > > > complex_mul_libcall: >

On Mon, Apr 4, 2011 at 5:02 PM, Arushi Aggarwal <arushi987 at gmail.com> wrote: > > >> Hi, >> Is it correct to convert, >>   %196 = load i32* %195, align 8                  ; <i32> [#uses=1] >>   %197 = zext i32 %196 to i64                     ; <i64> [#uses=1] >>   %198 = ptrtoint i8* %193 to i64                 ; <i64> [#uses=1]

On 4/4/2011 6:45 PM, Eli Friedman wrote: > On Mon, Apr 4, 2011 at 5:02 PM, Arushi Aggarwal<arushi987 at gmail.com> wrote: >> >>> Hi, >>> Is it correct to convert, >>> %196 = load i32* %195, align 8 ;<i32> [#uses=1] >>> %197 = zext i32 %196 to i64 ;<i64> [#uses=1] >>> %198 =

Hello Eli. Eli Friedman <eli.friedman at gmail.com> writes: > On Fri, Sep 25, 2009 at 2:41 PM, Óscar Fuentes <ofv at wanadoo.es> wrote: >> I filed a bug yesterday ( http://llvm.org/bugs/show_bug.cgi?id=5046 ) >> and Anton kindly explained that LLVM is doing the right thing as per the >> ABI (the GCC ABI, I'll add). >> >>  1. Is there a LLVM way of

On Wed, Oct 07, 2015 at 10:28:59AM +0200, Jonas Maebe via llvm-dev wrote: > > James Y Knight via llvm-dev wrote on Tue, 06 Oct 2015: > > >Certainly a mismatch between sret and not-sret from caller to callee could > >not possibly work on sparc, because sparc's calling convention for struct > >return is totally bonkers. > > It won't work on AArch64 either:

Dear All, Is it legal to have an alloca in a basic block other than a function's entry block? -- John T.