mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-15 04:30:12 +00:00
c19aadee66
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10318 91177308-0d34-0410-b5e6-96231b3b80d8
101 lines
3.4 KiB
C++
101 lines
3.4 KiB
C++
//===-- VM.cpp - LLVM Just in Time Compiler -------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file was developed by the LLVM research group and is distributed under
|
|
// the University of Illinois Open Source License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This tool implements a just-in-time compiler for LLVM, allowing direct
|
|
// execution of LLVM bytecode in an efficient manner.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "VM.h"
|
|
#include "llvm/Function.h"
|
|
#include "llvm/ModuleProvider.h"
|
|
#include "llvm/CodeGen/MachineCodeEmitter.h"
|
|
#include "llvm/CodeGen/MachineFunction.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
using namespace llvm;
|
|
|
|
VM::~VM() {
|
|
delete MCE;
|
|
delete &TM;
|
|
}
|
|
|
|
/// setupPassManager - Initialize the VM PassManager object with all of the
|
|
/// passes needed for the target to generate code.
|
|
///
|
|
void VM::setupPassManager() {
|
|
// Compile LLVM Code down to machine code in the intermediate representation
|
|
if (TM.addPassesToJITCompile(PM)) {
|
|
std::cerr << "lli: target '" << TM.getName()
|
|
<< "' doesn't support JIT compilation!\n";
|
|
abort();
|
|
}
|
|
|
|
// Turn the machine code intermediate representation into bytes in memory that
|
|
// may be executed.
|
|
if (TM.addPassesToEmitMachineCode(PM, *MCE)) {
|
|
std::cerr << "lli: target '" << TM.getName()
|
|
<< "' doesn't support machine code emission!\n";
|
|
abort();
|
|
}
|
|
}
|
|
|
|
/// runJITOnFunction - Run the FunctionPassManager full of
|
|
/// just-in-time compilation passes on F, hopefully filling in
|
|
/// GlobalAddress[F] with the address of F's machine code.
|
|
///
|
|
void VM::runJITOnFunction(Function *F) {
|
|
static bool isAlreadyCodeGenerating = false;
|
|
assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!");
|
|
|
|
// JIT the function
|
|
isAlreadyCodeGenerating = true;
|
|
PM.run(*F);
|
|
isAlreadyCodeGenerating = false;
|
|
}
|
|
|
|
/// getPointerToFunction - This method is used to get the address of the
|
|
/// specified function, compiling it if neccesary.
|
|
///
|
|
void *VM::getPointerToFunction(Function *F) {
|
|
void *&Addr = GlobalAddress[F]; // Check if function already code gen'd
|
|
if (Addr) return Addr;
|
|
|
|
// Make sure we read in the function if it exists in this Module
|
|
MP->materializeFunction(F);
|
|
|
|
if (F->isExternal())
|
|
return Addr = getPointerToNamedFunction(F->getName());
|
|
|
|
runJITOnFunction(F);
|
|
assert(Addr && "Code generation didn't add function to GlobalAddress table!");
|
|
return Addr;
|
|
}
|
|
|
|
/// recompileAndRelinkFunction - This method is used to force a function
|
|
/// which has already been compiled, to be compiled again, possibly
|
|
/// after it has been modified. Then the entry to the old copy is overwritten
|
|
/// with a branch to the new copy. If there was no old copy, this acts
|
|
/// just like VM::getPointerToFunction().
|
|
///
|
|
void *VM::recompileAndRelinkFunction(Function *F) {
|
|
void *&Addr = GlobalAddress[F]; // Check if function already code gen'd
|
|
|
|
// If it's not already compiled (this is kind of weird) there is no
|
|
// reason to patch it up.
|
|
if (!Addr) { return getPointerToFunction (F); }
|
|
|
|
void *OldAddr = Addr;
|
|
Addr = 0;
|
|
MachineFunction::destruct(F);
|
|
runJITOnFunction(F);
|
|
assert(Addr && "Code generation didn't add function to GlobalAddress table!");
|
|
TM.replaceMachineCodeForFunction(OldAddr, Addr);
|
|
return Addr;
|
|
}
|