search for: getsizeof

...malloc() to allocate space for it. Can I get the size as an llvm::Constant* (or other llvm::Value*) given an llvm::StructType* or other llvm::Type*? if you have DataLayout available, use the getTypeAllocSize method. If you don't have information about the target then you can use ConstantExpr::getSizeOf. The advantage of DataLayout is that it returns a number (eg: 8) while getSizeOf returns a mysterious expression (the optimizers will simplify it to a number, the same as getTypeAllocSize returns, if you provide them with DataLayout). Ciao, Duncan.

On Jan 20, 2013, at 3:21 , Duncan Sands <baldrick at free.fr> wrote: > if you have DataLayout available, use the getTypeAllocSize method. If you don't > have information about the target then you can use ConstantExpr::getSizeOf. The > advantage of DataLayout is that it returns a number (eg: 8) while getSizeOf > returns a mysterious expression (the optimizers will simplify it to a number, > the same as getTypeAllocSize returns, if you provide them with DataLayout). Thanks, Duncan. What's the difference betwe...

Is there a way to get the sizeof a type? Say I've created a struct type without any explicit attribtues, and I want to call malloc() to allocate space for it. Can I get the size as an llvm::Constant* (or other llvm::Value*) given an llvm::StructType* or other llvm::Type*? TIA, -- Rick

...;typeClass() == Type::Class ? dwarf::DW_TAG_class_type : > dwarf::DW_TAG_structure_type, > dbgCompileUnit_, > type->typeDefn()->linkageName().c_str(), > genDIFile(type->typeDefn()), > getSourceLineNumber(type->typeDefn()->location()), > getSizeOfInBits(type->irType()), > getAlignOfInBits(type->irType()), > getInt64Val(0), 0, > DIType(), > dbgFactory_.GetOrCreateArray(members.data(), members.size())); > > The 'getSizeOfInBits()' function and the others like it basically call > llvm::...

...evel debugging docs that line and column numbers are 1-based, not 0-based. I know that might seem obvious but it threw me off for a bit. 7) Another thing that confused me for a while is that the debugging APIs all want size, offset, and alignment values to be in bits, not bytes - but ConstantExpr::getSizeOf() et al return a size in bytes (which makse sense, since it behaves like C sizeof). More confusing, however, the comments for getSizeOf() doesn't say what units its result is in - I automatically assumed that getSizeOf and DIFactory were compatible. Probably the simplest thing would be to add...

...:getAlignment(const Type * type) { > // Calculates the alignment of T using "sizeof({i8, T}) - sizeof > (T)" > return ConstantExpr::getSub( > getSize(StructType::get(Type::Int8Ty, type, NULL)), > getSize(type)); > } Are ConstantExpr::getAlignOf, getSizeOf, and getOffsetOf what you're looking for? Dan

...Type::Class ? dwarf::DW_TAG_class_type : dwarf::DW_TAG_structure_type, >> dbgCompileUnit_, >> type->typeDefn()->linkageName().c_str(), >> genDIFile(type->typeDefn()), >> getSourceLineNumber(type->typeDefn()->location()), >> getSizeOfInBits(type->irType()), >> getAlignOfInBits(type->irType()), >> getInt64Val(0), 0, >> DIType(), >> dbgFactory_.GetOrCreateArray(members.data(), members.size())); >> >> The 'getSizeOfInBits()' function and the others like it...

...ass ? dwarf::DW_TAG_class_type : >> dwarf::DW_TAG_structure_type, >> dbgCompileUnit_, >> type->typeDefn()->linkageName().c_str(), >> genDIFile(type->typeDefn()), >> getSourceLineNumber(type->typeDefn()->location()), >> getSizeOfInBits(type->irType()), >> getAlignOfInBits(type->irType()), >> getInt64Val(0), 0, >> DIType(), >> dbgFactory_.GetOrCreateArray(members.data(), members.size())); >> >> The 'getSizeOfInBits()' function and the others like it ba...

...all, consider the following function from Core.cpp in LLVM 9.0.0: LLVMValueRef LLVMBuildMalloc(LLVMBuilderRef B, LLVMTypeRef Ty, const char *Name) { Type* ITy = Type::getInt32Ty(unwrap(B)->GetInsertBlock()->getContext()); Constant* AllocSize = ConstantExpr::getSizeOf(unwrap(Ty)); AllocSize = ConstantExpr::getTruncOrBitCast(AllocSize, ITy); Instruction* Malloc = CallInst::CreateMalloc(unwrap(B)->GetInsertBlock(), ITy, unwrap(Ty), AllocSize, nullptr, nullptr, &quo...

...Try to generate LLVM IR for it: Type *tp = p->getType(); AllocaInst* arg_alloc = builder.CreateAlloca(tp);//builder is IRBuilder if(tp->isPointerTy()){ Type* tpp = tp->getPointerElementType(); Type* ITy = Type::getInt32Ty(getGlobalContext()); Constant* AllocSize = ConstantExpr::getSizeOf(tpp) AllocSize = ConstantExpr::getTruncOrBitCast(AllocSize, ITy); CallInst::CreateMalloc(arg_alloc, ITy, tpp, AllocSize); } But the generated LLVM IR seems incorrect: %malloccall = tail call i8* bitcast (i8* (i64)* @malloc to i8* (i32)*)(i32 ptrtoint (i32* getelementptr (i32* null, i32 1) to...

...type) { >> // Calculates the alignment of T using "sizeof({i8, T}) - sizeof(T)" >> return ConstantExpr::getSub( >> getSize(StructType::get(Type::Int8Ty, type, NULL)), >> getSize(type)); >> } >> > > Are ConstantExpr::getAlignOf, getSizeOf, and getOffsetOf what > you're looking for? > > That will work. Now all I need is for the methods of DIFactory to take a Constant* instead of uint64. -- -- Talin -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-d...

For the size of a type to be calculated at runtime, there is a known trick with gep. Is there any similar trick for determining the alignment of a type at runtime for target-independent IR? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140924/887f8612/attachment.html>

How does LLVM-GCC emit the correct size for structures? Is structure packing part of the "platform specific" magic that GCC knows, or is there some "portable" way to put a structure size into LLVM byte code? Actually, I don't care if it is portable, as long as LLVM has some way to compute it for me, and I don't have to know about the underlying platform. Thanks,

...; there some "portable" way to put a structure size into LLVM byte code? > > Actually, I don't care if it is portable, as long as LLVM has some way > to compute it for me, and I don't have to know about the underlying > platform. You may want to look at ConstantExpr::getSizeOf(const Type*) -- Alkis

On Tue, Jul 20, 2010 at 2:46 PM, Talin <viridia at gmail.com> wrote: > On Tue, Jul 20, 2010 at 8:34 AM, Chris Lattner <clattner at apple.com> wrote: > >> >> On Jul 20, 2010, at 1:36 AM, Anton Korobeynikov wrote: >> >> >> used to make the code manipulating the union type "well typed". This >> >> approach seems work very well, is

...s_type : >>> dwarf::DW_TAG_structure_type, >>> dbgCompileUnit_, >>> type->typeDefn()->linkageName().c_str(), >>> genDIFile(type->typeDefn()), >>> getSourceLineNumber(type->typeDefn()->location()), >>> getSizeOfInBits(type->irType()), >>> getAlignOfInBits(type->irType()), >>> getInt64Val(0), 0, >>> DIType(), >>> dbgFactory_.GetOrCreateArray(members.data(), members.size())); >>> >>> The 'getSizeOfInBits()' function a...

...ompositeTypeEx( type->typeClass() == Type::Class ? dwarf::DW_TAG_class_type : dwarf::DW_TAG_structure_type, dbgCompileUnit_, type->typeDefn()->linkageName().c_str(), genDIFile(type->typeDefn()), getSourceLineNumber(type->typeDefn()->location()), getSizeOfInBits(type->irType()), getAlignOfInBits(type->irType()), getInt64Val(0), 0, DIType(), dbgFactory_.GetOrCreateArray(members.data(), members.size())); The 'getSizeOfInBits()' function and the others like it basically call llvm::ConstantExpr::getSizeOf() and then...

...e->typeClass() == Type::Class ? dwarf::DW_TAG_class_type : dwarf::DW_TAG_structure_type, > dbgCompileUnit_, > type->typeDefn()->linkageName().c_str(), > genDIFile(type->typeDefn()), > getSourceLineNumber(type->typeDefn()->location()), > getSizeOfInBits(type->irType()), > getAlignOfInBits(type->irType()), > getInt64Val(0), 0, > DIType(), > dbgFactory_.GetOrCreateArray(members.data(), members.size())); > > The 'getSizeOfInBits()' function and the others like it basically call llvm::Con...

...;    // Calculates the alignment of T using "sizeof({i8, T}) - sizeof(T)" >>>    return ConstantExpr::getSub( >>>        getSize(StructType::get(Type::Int8Ty, type, NULL)), >>>        getSize(type)); >>> } >> >> Are ConstantExpr::getAlignOf, getSizeOf, and getOffsetOf what >> you're looking for? >> > That will work. Now all I need is for the methods of DIFactory to take a > Constant* instead of uint64. ok. Feel free to add /// CreateBasicType - Create a basic type like int, float, etc. DIBasicType CreateBasicType(D...

...----------------------------------------------------------===// /// GetAlignOf constant expr - computes the alignment of a type in a target /// independent way (Note: the return type is an i64). static Constant *GetAlignOf(const Type* Ty) { return ConstantExpr::getAlignOf(Ty); } /// GetSizeOf constant expr - computes the (alloc) size of a type (in /// address-units, not bits) in a target independent way (Note: the return /// type is an i64). /// static Constant *GetSizeOf(const Type* Ty) { return ConstantExpr::getSizeOf(Ty); } /// GetOffsetOf constant expr - computes th...