similar to: Best way of implement a fat pointer for C

Dear All, In my development, a function returns a struct {i8*, i64}, and on the call site I need to assign the return value to a struct of type {some_struct*, i64}. One way to do it is to call the mutateType() method of llvm::Value on the return value of the function call; however, I’m concerned that this mutateType() method might be too disruptive (it’s discouraged to use it by the

Hi all, Please review this patch. It's fixing PR3232 comment #8. Function bar from 2008-03-24-BitFiled-And-Alloca.c compiles to: %struct.Key = type { { i32, i32 } } ... define i32 @bar(i64 %key_token2) nounwind { entry: %key_token2_addr = alloca i64 ; <i64*> [#uses=2] %retval = alloca i32 ; <i32*> [#uses=2] %iospec =

Hi Craig, Thanks for the information. Can you point to the source that specifies tGPR to be R0 - R7? I tried to search in ARMInstrThumb.td but couldn’t find it. Thanks, - Jie On Apr 14, 2019, at 15:28, Craig Topper <craig.topper at gmail.com<mailto:craig.topper at gmail.com>> wrote: I believe there is probably a separate instruction in LLVM for thumb2 add. Probably starting with t2

Sorry for not being specific enough. ARMv7-M includes Thumb and Thumb2. It has 12 regular registers (R0 - R12), and R8 - R12 are used. I can generate mov instruction that from/ R8-R12 to/from R0-R6. From this ARM page http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0068b/ch03s03s01.html R9 - R12 have their conventional usage, but I don’t if this is the reason we cannot use them

> On May 6, 2020, at 21:53, Krzysztof Parzyszek <kparzysz at quicinc.com> wrote: > > You can > 1. extract individual elements of {i8*, i64}, > 2. bitcast the first to some_struct*, > 3. insert them into a new struct of type {some_struct*, i64}. Thanks for the help. I’m thinking the same way. Now I’m stuck with how to create a struct; I know how to create a

Hi Evan, > LValue LV = EmitLV(lhs); > bool isVolatile = TREE_THIS_VOLATILE(lhs); > unsigned Alignment = expr_align(exp) / 8 > > It's using the alignment of the expression, rather than the memory > object of LValue. can't you just use expr_align(lhs) instead? > The patch saves the alignment of the memory object in LValue returned > by EmitLV().

Hello, I’m writing machine function passes for programs running with ARMv7-M ISA. My pass adds some instructions to the original code, and now I got fatal error: error in backend: out of range pc-relative fixup value when llvm generates native code after running the transformation pass. I think it’s because my transformation pass increases the size of the original code and thus some branch

As far as I can tell, when you construct a type using the support library StructType::get, you have to pass in a list of types. How can you make a Recursive type by passing in a pointer to the type you are constucting. An example where something really simple like the line below was output would be perfect. %struct.linked_list = type { %struct.linked_list*, %sbyte* } Thanks for any help,

Sorry I got really overwhelmed by so many classes and member functions in LLVM. So would you please clarify some problems I have? 1. If I see this instruction in the function. %S.i = alloca %struct.SimpleStruct Suppose SimpleStruct is as following: struct.SimpleStruct = type { int, double } When I read the instruction, how can I know the type of simplstruct, should I use 'getType'

On Mon, 7 Mar 2005, John Carrino wrote: > As far as I can tell, when you construct a type using the support > library StructType::get, you have to pass in a list of types. How can > you make a Recursive type by passing in a pointer to the type you are > constucting. > > An example where something really simple like the line below was output > would be perfect. > >

>> An example where something really simple like the line below was output >> would be perfect. >> >> %struct.linked_list = type { %struct.linked_list*, %sbyte* } > > Use something like this: > > PATypeHolder StructTy = OpaqueType::get(); > std::vector<const Type*> Elts; > Elts.push_back(PointerType::get(StructTy)); >

Thanks for the information I am trying to use one of your examples for recursive data structures: ========================= PATypeHolder StructTy = OpaqueType::get(); std::vector<const Type*> Elts; Elts.push_back(PointerType::get(StructTy)); Elts.push_back(PointerType::get(Type::SByteTy)); StructType *NewSTy = StructType::get(Elts); // At this point, NewSTy = "{ opaque*, sbyte*

Dear all, I’m developing Clang&LLVM on MacOS Catalina 10.15. Now every time I "make clang", the building systems rebuilds all the .inc files generated by cmake, which essentially rebuilds all the tablegen files in llvm, although I did not change any of the tablegen files. The building is unnecessary and slow, especially when it builds the X86GenSubtargetInfo.inc. Is there a way to

This is for BPF output. BPF program output bytes to perf through a tracepoint. For decoding such data, we need a way to describe the format of the buffer. This patch is a try which gives each variable a unique number by introducing a new intrinsic 'llvm.typeid.for'. At the bottom is an example of using that intrinsic and the result of $ clang -target bpf -O2 -c -S ./test_typeid.c

Hi all, An oddity that has existed for a long time in the IR is that PointerType derives from SequentialType. Per subject I propose to make PointerType derive from Type for a couple of reasons: - Values of type PointerType are unlike the other SequentialTypes (arrays and vectors) in that they do not hold values of the element type. By moving PointerType we can unify certain aspects of how the

On Tue, 15 Mar 2005, xavier wrote: > Thanks for the information > I am trying to use one of your examples for recursive data structures: > > ========================= > PATypeHolder StructTy = OpaqueType::get(); > std::vector<const Type*> Elts; > Elts.push_back(PointerType::get(StructTy)); > Elts.push_back(PointerType::get(Type::SByteTy)); > StructType *NewSTy =

On Tue, 8 Mar 2005, Vladimir Merzliakov wrote: >>> An example where something really simple like the line below was output >>> would be perfect. >>> >>> %struct.linked_list = type { %struct.linked_list*, %sbyte* } >> >> Use something like this: >> >> PATypeHolder StructTy = OpaqueType::get(); >> std::vector<const

Hi all, I’m trying to insert some add/sub and push/pop instructions in a MachineFunction pass for ARMv7-M. However, I encountered something weird. For an add, when I use BuildMI(….., TII->get(ARM::tADDi8), reg).addReg(reg).addReg(reg).addImm(imm). if reg is R0 - R7, everything is fine: I would get something like adds r1, 4 But if I use R8 - R12 as the reg in the BuildMI, I wouldn’t get

Hi, We build a type with StructType::get(fModule->getContext(), fDspFields, false); with a fDspFields (std::vector<const llvm::Type*> fDspFields;) that is not yet completely known when we have to build the type. It is possible to add fields in a already build type? Thanks Stéphane Letz

Thanks David. I ended up trying this over the weekend (see https://github.com/llvm-project/llvm-project/compare/ master...pcc:pointertype). It ended up being a net reduction in code size so seems like a useful cleanup even independent of the typeless pointer work, I'll see if I can send a patch to the list. FWIW I think this directly helps towards the migration because we would have a clearer