llvm-c++-api

问题 TL,DR: How can I force clang to export the symbols of implicitly instantiated functions even when -O3 is active? Let's take the following code: #include <iostream> #include <llvm/Support/DynamicLibrary.h> #include <llvm/ExecutionEngine/ExecutionEngine.h> #include <llvm/ExecutionEngine/RTDyldMemoryManager.h> template <typename T> __attribute__((noinline)) int twice(const T& t) { return t * 2; } int thrice(const int& t) { return t * 3; } int main() { std::cout << twice(5) << std::endl; std:

问题 In LLVM, a function looks like this: define i32 @foo(i32, i32) By playing with lli , I noticed that this is also accepted: define i32 @foo(i32 %first-arg, i32 %second-arg) and then the arguments are accessible from the given names. How should I generate such a function with named arguments using the C++ API? I checked the documentation and it seems that there's no way to supply names to FunctionType::get as its second argument is of type ArrayRef<Type *> where there isn't a field for name (or

问题 In LLVM, a function looks like this: define i32 @foo(i32, i32) By playing with lli , I noticed that this is also accepted: define i32 @foo(i32 %first-arg, i32 %second-arg) and then the arguments are accessible from the given names. How should I generate such a function with named arguments using the C++ API? I checked the documentation and it seems that there's no way to supply names to FunctionType::get as its second argument is of type ArrayRef<Type *> where there isn't a field for name (or

问题 I am writing LLVM IR code, can I call a function in another .ll file? For example: In a.ll file, there is a function foo(); Can I use this function in b.ll, like just call foo? If so, how can I include a.ll Thanks 回答1: You need to add declaration of function foo in the ll file in which you are calling it, then as usual convert link ll files to generate executable llvm-link a.ll b.ll -o a.out example a.ll declare i32 @foo(i32) define i32 @main() { start: %0 = call i32 @foo(i32 0) ret i32 %0 }

问题 I am trying to migrate my project from llvm3.6.2 to llvm3.8.1. In my code, I have used AliasAnalysis and I am changing my code as follows: #if defined(DDP_LLVM_VERSION_3_8) AU.addRequired<AAResultsWrapperPass>(); #else AU.addRequired<AliasAnalysis>(); #endif And I am passing AliasAnalysis to the function as follow: #if defined(DDP_LLVM_VERSION_3_8) foo(*F,getAnalysis<AAResultsWrapperPass>().getAAResults()); #else foo(*F,getAnalysis<AliasAnalysis>()); #endif Function declaration is as follow:

问题 I'm trying to get loop information from IR by writing a function pass. So I followed some examples and wrote like following. I'm not very familiar with writing passes and pass managers. #include <iostream> #include "llvm/LLVMContext.h" #include "llvm/Module.h" #include "llvm/Function.h" #include "llvm/BasicBlock.h" #include "llvm/Analysis/LoopInfo.h" #include "llvm/Support/IRReader.h" #include "llvm/Support/SourceMgr.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Analysis/LoopInfo.h"

问题 I am working on a toy language written using the llvm c++ api and I am trying to implement arrays. I have tried several different things none of which have worked very well. Here is what I am going for: A type that can resemble an array (struct, vector or array would work) Can be passed to and returned from functions Can have infinitely nested arrays (eg. [8 x [8 x [8 x [...] ) Can be re-assignable Arrays are all of the same type Arrays are of finite length specified on creation. Ideally,

问题 I want to write some code that, given an LLVM function F, creates an exact copy in the same module (so the copy can be manipulated later while preserving the original). I want to do this with the CloneFunctionInto method. My current attempt involves trying to insert each (new arg,old arg) pair into the VMap. Previously I've tried inserting an uninitialised VMap and putting the pair the other way round. Impressively, all 3 have resulted in the exact same error message: Assertion `VMap.count(&I

问题 I am implementing a front-end for a JIT compiler using LLVM. I started by following the Kaleidoscope example in the LLVM tutorial. I know how to generate and JIT LLVM IR using the LLVM C++ API. I also know how to call the JITed function, using the "getPointerToFunction" method of llvm::ExecutionEngine. getPointerToFunction returns a void* which I must then cast to the correct function type. For example, in my compiler I have unit test that looks like the following: void* compiled_func =

问题 What's the difference between "ModulePassManagers", "FunctionPassManager" and "BasicBlockPassManagers" in LLVM? And, does "FunctionPassManager" can only be used on "function" type in LLVM-IR? 回答1: LLVM IR is subdivided into different units. The different units of LLVM IR are as follows Modules Functions Basic blocks Instructions A module consists of functions that are in turn made up of different basic blocks that contain a sequence of instructions. The different pass managers operate on