What is Alloca in LLVM?

The ‘alloca’ instruction is commonly used to represent automatic variables that must have an address available. More you can find here. Some notes from llvm IR book: The contents of an entire LLVM file, either assembly or bitcode, are said to define an LLVM module.

What is LLVM value?

LLVM Value Representation. This is a very important LLVM class. It is the base class of all values computed by a program that may be used as operands to other values. Value is the super class of other important classes such as Instruction and Function.

Does LLVM optimize?

The LLVM Link Time Optimizer provides complete transparency, while doing intermodular optimization, in the compiler tool chain. Its main goal is to let the developer take advantage of intermodular optimizations without making any significant changes to the developer’s makefiles or build system.

What is a Bitcast?

Bitcast is a community-driven marketplace to educate software developers through video.

What is context LLVM?

It (opaquely) owns and manages the core “global” data of LLVM’s core infrastructure, including the type and constant uniquing tables. Just think of it as a reference to the core LLVM “engine” that you should pass to the various methods that require a LLVMContext .

How do you find the argument of a function in LLVM?

You can use Function::getArgumentList() method to get a list of function’s arguments. Then, you traverse it with iterators – ArgumentListType::begin() and ArgumentListType::end() . UPD: The current way of iterating over arguments is arg_begin() / arg_end() / args() methods.

What is LLVM pass?

All LLVM passes are subclasses of the Pass class, which implement functionality by overriding virtual methods inherited from Pass .

When to return the alignment of memory allocated by the instruction?

for use only in special circumstances that need to generically transform a whole instruction (eg: IR linking and vectorization). More… Return the alignment of the memory that is being allocated by the instruction. More… Return true if this alloca is in the entry block of the function and is a constant size. More…

What is the use of getoperand () in LLVM?

References llvm::User::getOperand (). Get the number of elements allocated. For a simple allocation of a single element, this will return a constant 1 value. Definition at line 100 of file Instructions.h. References llvm::User::getOperand ().

What does return true mean in LLVM?

Return true if the instruction will return (unwinding is considered as a form of returning control flow here). More… Return true if the instruction is a variety of EH-block. More… Return true if the instruction is a llvm.lifetime.start or llvm.lifetime.end marker.