I want to replace the call to malloc with call to cumemhostalloc function.
float *h_A=(float *)malloc(size);
should be replaced with
cuMemHostAlloc((void **)&h_A,size,2);
I use the following code for this,
*if (dyn_cast<CallInst> (j))
{
Ip=cast<Instruction>(j);
CastInst* ci_hp = new BitCastInst(ptr_h_A, PointerTy_23, "" );
BB->getInstList().insert(Ip,ci_hp);
errs()<<"\n Cast instruction is inserted"<<*ci_hp;
li_size = new LoadInst(al_size, "", false);
li_size->setAlignment(4);
BB->getInstList().insert(Ip,li_size);
errs()<<"\n Load instruction is inserted"<<*li_size;
ConstantInt* const_int32_34 = ConstantInt::get(M->getContext(), APInt(32, StringRef("2"), 10));
std::vector<Value*> cumemhaparams;
cumemhaparams.push_back(ci_hp);
cumemhaparams.push_back(li_size);
cumemhaparams.push_back(const_int32_34);
CallInst* cumemha = CallInst::Create(func_cuMemHostAlloc, cumemhaparams, "");
cumemha->setCallingConv(CallingConv::C);
cumemha->setTailCall(false);
AttrListPtr cumemha_PAL;
cumemha->setAttributes(cumemha_PAL);
ReplaceInstWithInst(callinst->getParent()->getInstList(), j,cumemha);*
}
But I get the following error,
/home/project/llvmfin/llvm-3.0.src/lib/VMCore/Value.cpp:287: void llvm::Value::replaceAllUsesWith(llvm::Value*): Assertion `New->getType() == getType() && "replaceAllUses of value with new value of different type!"' failed.
Is it because the call to malloc is replaced with a function that has a different signature?
Almost. Call to malloc produce a value, your function - does not. So, you have to replace call with a load, not with another call
Also, looking into your code:
Do not play with instlists directly. Use IRBuilder + iterators instead
You can check for CallInst and declare var at the same time, no need to additional cast to Instruction.
Related
I am playing with llvm (and antlr), working vaguely along the lines of the Kaleidoscope tutorial. I successfully created LLVM-IR code from basic arithmetic expressions both on top-level and as function definitions, which corresponds to the tutorial chapters up to 3.
Now I would like to incrementally add JIT support, starting with the top-level arithmetic expressions. Here is my problem:
Basic comparison makes it seem as if I follow the same sequence of function calls as the tutorial, only with a simpler code organization
The generated IR code looks good
The function definition is apparently found, since otherwise the code would exit (i verified this by intentionally looking for a wrongly spelled function name)
However the call of the function pointer created by JIT evaluation always returns zero.
These snippets (excerpt) are executed as part of the antlr visitor of the main/entry-node of my grammar:
//Top node main -- top level expression
antlrcpp::Any visitMain(ExprParser::MainContext *ctx)
{
llvm::InitializeNativeTarget();
llvm::InitializeNativeTargetAsmPrinter();
llvm::InitializeNativeTargetAsmParser();
TheJIT = ExitOnErr( llvm::orc::KaleidoscopeJIT::Create() );
InitializeModuleAndPassManager();
// ... Code which visits the child nodes ...
}
InitializeModuleAndPassManager() is the same as in the tutorial:
static void InitializeModuleAndPassManager()
{
// Open a new context and module.
TheContext = std::make_unique<llvm::LLVMContext>();
TheModule = std::make_unique<llvm::Module>("commandline", *TheContext);
TheModule->setDataLayout(TheJIT->getDataLayout());
// Create a new builder for the module.
Builder = std::make_unique<llvm::IRBuilder<>>(*TheContext);
// Create a new pass manager attached to it.
TheFPM = std::make_unique<llvm::legacy::FunctionPassManager>(TheModule.get());
// Do simple "peephole" optimizations and bit-twiddling optzns.
TheFPM->add(llvm::createInstructionCombiningPass());
// Reassociate expressions.
TheFPM->add(llvm::createReassociatePass());
// Eliminate Common SubExpressions.
TheFPM->add(llvm::createGVNPass());
// Simplify the control flow graph (deleting unreachable blocks, etc).
TheFPM->add(llvm::createCFGSimplificationPass());
TheFPM->doInitialization();
}
This is the function which handles the top-level expression and which is also supposed to do JIT evaluation:
//Bare expression without function definition -- create anonymous function
antlrcpp::Any visitBareExpr(ExprParser::BareExprContext *ctx)
{
string fName = "__anon_expr";
llvm::FunctionType *FT = llvm::FunctionType::get(llvm::Type::getDoubleTy(*TheContext), false);
llvm::Function *F = llvm::Function::Create(FT, llvm::Function::ExternalLinkage, fName, TheModule.get());
llvm::BasicBlock *BB = llvm::BasicBlock::Create(*TheContext, "entry", F);
Builder->SetInsertPoint(BB);
llvm::Value* Expression=visit(ctx->expr()).as<llvm::Value* >();
Builder->CreateRet(Expression);
llvm::verifyFunction(*F);
//TheFPM->run(*F);//outcommented this because i wanted to try JIT before optimization-
//it causes a compile error right now because i probably lack some related code.
//However i do not assume that a missing optimization run will cause the problem that i have
F->print(llvm::errs());
// Create a ResourceTracker to track JIT'd memory allocated to our
// anonymous expression -- that way we can free it after executing.
auto RT = TheJIT->getMainJITDylib().createResourceTracker();
auto TSM = llvm::orc::ThreadSafeModule(move(TheModule), move(TheContext));
ExitOnErr(TheJIT->addModule(move(TSM), RT));
InitializeModuleAndPassManager();
// Search the JIT for the __anon_expr symbol.
auto ExprSymbol = ExitOnErr(TheJIT->lookup("__anon_expr"));
// Get the symbol's address and cast it to the right type (takes no
// arguments, returns a double) so we can call it as a native function.
double (*FP)() = (double (*)())(intptr_t)ExprSymbol.getAddress();
double ret = FP();
fprintf(stderr, "Evaluated to %f\n", ret);
// Delete the anonymous expression module from the JIT.
ExitOnErr(RT->remove());
return F;
}
Now this is what happens as an example:
[robert#robert-ux330uak test4_expr_llvm_2]$ ./testmain '3*4'
define double #__anon_expr() {
entry:
ret float 1.200000e+01
}
Evaluated to 0.000000
I would be thankful for any ideas about what I might be doing wrong.
I want to insert below function:
void foo(uintptr_t addr) {}
Function type declaration:
std::vector<llvm::Type*> params = {Type::getInt64Ty(Context)};
FunctionType* funcTy = FunctionType::get(Type::getVoidTy(Context), params, false);
Call insertion:
llvm::IRBuilder<> builder(I);
builder.SetInsertPoint(bb, ++builder.GetInsertPoint());
// uintptr_t addr = 123213
ArrayRef< Value* > args(ConstantInt::get(Type::getInt64Ty(llvmContext), addr, false));
builder.CreateCall(F,args);
Got: Calling a function with a bad signature!"' failed.
Please help with the correct way of doing this
#arnt is correct. I guess you want the "addr" as an int to your hook function. Remember, this addr can't be statically determined by the compiler, but it's a dynamic address. So you need to replace your args with something like:
ArrayRef< Value* > args(CastInst::CreateIntegerCast(addr, F->getFunctionType()->getFunctionParamType(0), true, "", InsertPoint))
You can use your IRBuilder to do this. This is actually instrument a new instruction to dynamically convert an "addr" into a integer, then you can pass it to your hook function.
I'm trying to call a method on an object from inside my compiled llvm JIT code.
I've read the answer here ( Can I bind an existing method to a LLVM Function* and use it from JIT-compiled code? ) but my case is slightly different, as my method requires an argument.
If I'm understanding everything correctly, I need to wrap my method with a function, but how can I store the pointer to my instance to use as the first argument when calling?
Here's a short example (omited some irrelevant parts)
class Foo:
{
public:
Foo();
float getValue(char * name);
};
float fooWrap(Foo *foo, char * name)
{
foo->getValue(name);
}
Foo::Foo()
{
// snipped llvm init stuff
std::vector<llvm::Type*> fun_args;
fun_args.push_back(llvm::Type::getInt8Ty(context)); // Pointer to this instance (pretty sure is wrong)
fun_args.push_back(llvm::Type::getInt8PtrTy(context)); // char array *
llvm::FunctionType *FT = llvm::FunctionType::get(llvm::Type::getFloatTy(context), fun_args, false);
llvm::Function * F = llvm::Function::Create(FT, llvm::Function::ExternalLinkage, "foo", module);
engine->addGlobalMapping(F, &fooWrap);
// later
llvm::Value *instance = llvm::ConstantInt::get(context, llvm::APInt((intptr_t) &this)); // wont compile, can't construct APInt from intptr_t
std::vector<llvm::Value*> args;
args.push_back(instance);
args.push_back(builder.CreateGlobalStringPtr("test"));
builder.CreateCall(F, args);
}
Any help would be greatly appreciated.
The argument type ended up being:
llvm::Type::getIntNTy(context, sizeof(uintptr_t)*8)
And the value was set with:
llvm::Value *instance = llvm::ConstantInt::get(llvm::Type::getIntNTy(context, sizeof(uintptr_t)*8), (uintptr_t) this);
This ensured that the pointer size was always correct for the compiled platform.
Seems to me like your question can be summed up by:
How to convert some object pointer in my code to an LLVM Value?
And your approach is correct - create a constant int with the value of the pointer as casted to an integer. Your error is just an incorrect usage of APInt's constructor - and in fact you don't need an APInt to start with, you can just do ConstantInt::get(context, (uintptr_t)this) (which works by constructing an APInt itself, as you can see in its implementation).
I know the basics of interacting with lua and C, and I am currently trying to perform the following line of lua in c++
Func1():Func2().Table1.value1
I am trying to get the value of "value2" and use it in my C program. The following is the code I wrote to attempt to get this value in C.
int GetNumber()
{
int retn = 0;
g_clientlua.lua_getfield(LUA_REGISTRYINDEX, "Player");
g_clientlua.lua_getfield(-1, "Func2");
g_clientlua.lua_getfield(LUA_GLOBALSINDEX, "Func1");
g_clientlua.lua_call(0, 1);
g_clientlua.lua_call(1, 1);
if (g_clientlua.lua_isnil(-1))
return retn;
g_clientlua.lua_getfield(-1, "Table1");
if (g_clientlua.lua_isnil(-1))
return retn;
g_clientlua.lua_getfield(-1, "value1");
if (g_clientlua.lua_isnil(-1))
return retn;
retn = (int)g_clientlua.lua_tointeger(-1);
}
The clientlua thing is an object that basically just allows me to call a method which calls it's lua_* function equivalent and fills the lua_state pointer parameter with a member variable that is a pointer to the lua state.
Every time I call this, it complains about me causing a lua stack leak. To solve this, I tried adding a lua_pop(3) to the end, but then it just crashes my program without reporting an error, so I assume I am doing something wrong.
Anyone have any words of wisdom for me? Kinda lost here. I doubt the above code is even written properly, how would I write the above lua call in C?
You need to call Func1 before you try to get Func2 as Func2 comes from the table that Func1 returns (and not from the global table).
Then you need to call Func2 and look up Table1 in that returned value, etc.
What "stack leak" complaint are you getting? If you are calling this function from C directly then yes, you need to be sure that anything you put on the lua stack (that isn't for consumption by the caller, etc.) is popped from the lua stack before you return.
The GetNumber function isn't doing exactly the same as the lua snippet you're going for. Specifically GetNumber is getting the value of "Func2" from the registry while your lua snippet is getting the value of "Func2" from the table returned by Func1(). Unless you're certain that registry.Player.Func2 == Func1().Func2 is always true, your C++ version will not have the same behavior.
Let's break down Func1():Func2().Table1.value1 into more explicit steps to help with the C translation:
Get function associated with _G.Func1
Call that function and get a table back
Get function associated with "Func2" from the returned table in step 2
Call that function and pass as argument the table from step 2. Get another table back as result
I found it helpful to track what the stack contains as a side-comment as the operations are performed:
int GetNumber()
{
// Func1()
gclientlua.lua_getfield(LUA_GLOBALSINDEX, "Func1"); // Func1
g_clientlua.lua_call(0, 1); // {}
// Func2( {} )
g_clientlua.lua_getfield(-1, "Func2"); // {}, Func2
g_clientlua.lua_insert(-2); // Func2, {}
g_clientlua.lua_call(1, 1); // {}
if( g_clientlua.lua_type(-1) != LUA_TTABLE )
{
g_clientlua.lua_pop(1);
return 0;
}
// {}.Table1
g_clientlua.lua_getfield(-1, "Table1"); // {}, {}(Table1)
if( g_clientlua.lua_type(-1) != LUA_TTABLE )
{
g_clientlua.lua_pop(2);
return 0;
}
// tonumber( Table1.value1 )
g_clientlua.lua_getfield(-1, "value1"); // {}, {}(Table1), value1
int retn = g_clientlua.lua_tointeger(-1);
g_clientlua.lua_pop(3);
return retn;
}
Notice that GetNumber pops off all the arguments it places on the stack before returning. This ensures that GetNumber leaves the lua stack the way it was found. This can probably be automated with RAII if you're using C++.
I am attempting to write some compiler and use LLVM to generate intermediate code. Unfortunately, LLVM documentation is not very great and even somewhat confusing.
At the moment I have lexer,grammar and AST implemented. I was also following some examples found on Internet. My current AST works as follows: it has the abstract base class Tree*, from which other trees inherit (so, like one for variable definition, one for statement list, one for binary expression etc.).
I am trying to implement the variable definition, so for the input
class Test{
int main()
{
int x;
}
}
I want LLVM output to be:
; ModuleID = "Test"
define i32 #main() {
entry:
%x = alloca i32
return i32 0
}
However, right now I can get %x = alloca i32 part to the part where main function is created, but the actual output is missing the %x = alloca i32. So, the output I'm getting is as follows:
; ModuleID = "Test"
define i32 #main() {
entry:
return i32 0
}
my Codegen() for variable declaration is shown bellow (symbol table for now is just a list, I am trying to keep things as simple as possible at the moment):
llvm::Value *decafStmtList::Codegen() {
string name = SyandTy.back(); // Just a name of a variable
string type = SyandTy.front(); // and its type in string format
Type* typeVal = getLLVMType(decafType(str2DecafType(type))); // get LLVM::*Type representation
llvm::AllocaInst *Alloca = Builder.CreateAlloca(typeVal, 0, name.c_str());
Value *V = Alloca;
return Alloca;//Builder.CreateLoad(V, name.c_str());
}
The part where I am generating my #main is as follows:
Note: I have commented out the print_int function (this is the function I will use later to print things, but for now I don't need it). If I'll uncomment the print_int function, TheFunction will not pass verifier(TheFunction) -> complains about module being broken and parameters not matching the signature.
Function *gen_main_def(llvm::Value *RetVal, Function *print_int) {
if (RetVal == 0) {
throw runtime_error("something went horribly wrong\n");
}
// create the top-level definition for main
FunctionType *FT = FunctionType::get(IntegerType::get(getGlobalContext(), 32), false);
Function *TheFunction = Function::Create(FT, Function::ExternalLinkage, "main", TheModule);
if (TheFunction == 0) {
throw runtime_error("empty function block");
}
// Create a new basic block which contains a sequence of LLVM instructions
BasicBlock *BB = BasicBlock::Create(getGlobalContext(), "entry", TheFunction);
// All subsequent calls to IRBuilder will place instructions in this location
Builder.SetInsertPoint(BB);
/*
Function *CalleeF = TheModule->getFunction(print_int->getName());
if (CalleeF == 0) {
throw runtime_error("could not find the function print_int\n");
}*/
// print the value of the expression and we are done
// Value *CallF = Builder.CreateCall(CalleeF, RetVal, "calltmp");
// Finish off the function.
// return 0 from main, which is EXIT_SUCCESS
Builder.CreateRet(ConstantInt::get(getGlobalContext(), APInt(32, 0)));
return TheFunction;
}
If someone knows why my Alloca object is not being generated, please help me out - any hints will be greatly appreciated.
Thank you
EDIT:
Codegen is called from the grammar:
start: program
program: extern_list decafclass
{
ProgramAST *prog = new ProgramAST((decafStmtList *)$1, (ClassAST *)$2);
if (printAST) {
cout << getString(prog) << endl;
}
Value *RetVal = prog->Codegen();
delete $1; // get rid of abstract syntax tree
delete $2; // get rid of abstract syntax tree
// we create an implicit print_int function call to print
// out the value of the expression.
Function *print_int = gen_print_int_def();
Function *TheFunction = gen_main_def(RetVal, print_int);
verifyFunction(*TheFunction);
}
EDIT: I figured it out, basically the createAlloca has to be called after the basicblock when generating main;
There are two weird things here:
All you do is call Builder.CreateRet... I don't see how there could be any code in main unless you call something that creates the corresponding instructions. In particular, you never seem to call the CodeGen part.
You pass a size of zero to CreateAlloc. I think the size should be one for a single variable.
Also, make sure that you don't call any LLVM optimization passes after generating your code. Those passes would optimize the value away (it's never used, thus dead code).