mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-07-19 19:30:10 +00:00
9133fe2895
the Transforms library. This reduces debug library size by 132 KB, debug binary size by 376 KB, and reduces link time for llvm tools slightly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33939 91177308-0d34-0410-b5e6-96231b3b80d8
246 lines
8.9 KiB
C++
246 lines
8.9 KiB
C++
//===- RaiseAllocations.cpp - Convert %malloc & %free calls to insts ------===//
|
|
//
|
|
// 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 file defines the RaiseAllocations pass which convert malloc and free
|
|
// calls to malloc and free instructions.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#define DEBUG_TYPE "raiseallocs"
|
|
#include "llvm/Transforms/IPO.h"
|
|
#include "llvm/Constants.h"
|
|
#include "llvm/DerivedTypes.h"
|
|
#include "llvm/Module.h"
|
|
#include "llvm/Instructions.h"
|
|
#include "llvm/Pass.h"
|
|
#include "llvm/Support/CallSite.h"
|
|
#include "llvm/Support/Compiler.h"
|
|
#include "llvm/ADT/Statistic.h"
|
|
using namespace llvm;
|
|
|
|
STATISTIC(NumRaised, "Number of allocations raised");
|
|
|
|
namespace {
|
|
// RaiseAllocations - Turn %malloc and %free calls into the appropriate
|
|
// instruction.
|
|
//
|
|
class VISIBILITY_HIDDEN RaiseAllocations : public ModulePass {
|
|
Function *MallocFunc; // Functions in the module we are processing
|
|
Function *FreeFunc; // Initialized by doPassInitializationVirt
|
|
public:
|
|
RaiseAllocations() : MallocFunc(0), FreeFunc(0) {}
|
|
|
|
// doPassInitialization - For the raise allocations pass, this finds a
|
|
// declaration for malloc and free if they exist.
|
|
//
|
|
void doInitialization(Module &M);
|
|
|
|
// run - This method does the actual work of converting instructions over.
|
|
//
|
|
bool runOnModule(Module &M);
|
|
};
|
|
|
|
RegisterPass<RaiseAllocations>
|
|
X("raiseallocs", "Raise allocations from calls to instructions");
|
|
} // end anonymous namespace
|
|
|
|
|
|
// createRaiseAllocationsPass - The interface to this file...
|
|
ModulePass *llvm::createRaiseAllocationsPass() {
|
|
return new RaiseAllocations();
|
|
}
|
|
|
|
|
|
// If the module has a symbol table, they might be referring to the malloc and
|
|
// free functions. If this is the case, grab the method pointers that the
|
|
// module is using.
|
|
//
|
|
// Lookup %malloc and %free in the symbol table, for later use. If they don't
|
|
// exist, or are not external, we do not worry about converting calls to that
|
|
// function into the appropriate instruction.
|
|
//
|
|
void RaiseAllocations::doInitialization(Module &M) {
|
|
|
|
// Get Malloc and free prototypes if they exist!
|
|
MallocFunc = M.getFunction("malloc");
|
|
if (MallocFunc) {
|
|
const FunctionType* TyWeHave = MallocFunc->getFunctionType();
|
|
|
|
// Get the expected prototype for malloc
|
|
const FunctionType *Malloc1Type =
|
|
FunctionType::get(PointerType::get(Type::Int8Ty),
|
|
std::vector<const Type*>(1, Type::Int64Ty), false);
|
|
|
|
// Chck to see if we got the expected malloc
|
|
if (TyWeHave != Malloc1Type) {
|
|
// Check to see if the prototype is wrong, giving us sbyte*(uint) * malloc
|
|
// This handles the common declaration of: 'void *malloc(unsigned);'
|
|
const FunctionType *Malloc2Type =
|
|
FunctionType::get(PointerType::get(Type::Int8Ty),
|
|
std::vector<const Type*>(1, Type::Int32Ty), false);
|
|
if (TyWeHave != Malloc2Type) {
|
|
// Check to see if the prototype is missing, giving us
|
|
// sbyte*(...) * malloc
|
|
// This handles the common declaration of: 'void *malloc();'
|
|
const FunctionType *Malloc3Type =
|
|
FunctionType::get(PointerType::get(Type::Int8Ty),
|
|
std::vector<const Type*>(), true);
|
|
if (TyWeHave != Malloc3Type)
|
|
// Give up
|
|
MallocFunc = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
FreeFunc = M.getFunction("free");
|
|
if (FreeFunc) {
|
|
const FunctionType* TyWeHave = FreeFunc->getFunctionType();
|
|
|
|
// Get the expected prototype for void free(i8*)
|
|
const FunctionType *Free1Type = FunctionType::get(Type::VoidTy,
|
|
std::vector<const Type*>(1, PointerType::get(Type::Int8Ty)), false);
|
|
|
|
if (TyWeHave != Free1Type) {
|
|
// Check to see if the prototype was forgotten, giving us
|
|
// void (...) * free
|
|
// This handles the common forward declaration of: 'void free();'
|
|
const FunctionType* Free2Type = FunctionType::get(Type::VoidTy,
|
|
std::vector<const Type*>(),true);
|
|
|
|
if (TyWeHave != Free2Type) {
|
|
// One last try, check to see if we can find free as
|
|
// int (...)* free. This handles the case where NOTHING was declared.
|
|
const FunctionType* Free3Type = FunctionType::get(Type::Int32Ty,
|
|
std::vector<const Type*>(),true);
|
|
|
|
if (TyWeHave != Free3Type) {
|
|
// Give up.
|
|
FreeFunc = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Don't mess with locally defined versions of these functions...
|
|
if (MallocFunc && !MallocFunc->isDeclaration()) MallocFunc = 0;
|
|
if (FreeFunc && !FreeFunc->isDeclaration()) FreeFunc = 0;
|
|
}
|
|
|
|
// run - Transform calls into instructions...
|
|
//
|
|
bool RaiseAllocations::runOnModule(Module &M) {
|
|
// Find the malloc/free prototypes...
|
|
doInitialization(M);
|
|
|
|
bool Changed = false;
|
|
|
|
// First, process all of the malloc calls...
|
|
if (MallocFunc) {
|
|
std::vector<User*> Users(MallocFunc->use_begin(), MallocFunc->use_end());
|
|
std::vector<Value*> EqPointers; // Values equal to MallocFunc
|
|
while (!Users.empty()) {
|
|
User *U = Users.back();
|
|
Users.pop_back();
|
|
|
|
if (Instruction *I = dyn_cast<Instruction>(U)) {
|
|
CallSite CS = CallSite::get(I);
|
|
if (CS.getInstruction() && CS.arg_begin() != CS.arg_end() &&
|
|
(CS.getCalledFunction() == MallocFunc ||
|
|
std::find(EqPointers.begin(), EqPointers.end(),
|
|
CS.getCalledValue()) != EqPointers.end())) {
|
|
|
|
Value *Source = *CS.arg_begin();
|
|
|
|
// If no prototype was provided for malloc, we may need to cast the
|
|
// source size.
|
|
if (Source->getType() != Type::Int32Ty)
|
|
Source =
|
|
CastInst::createIntegerCast(Source, Type::Int32Ty, false/*ZExt*/,
|
|
"MallocAmtCast", I);
|
|
|
|
std::string Name(I->getName()); I->setName("");
|
|
MallocInst *MI = new MallocInst(Type::Int8Ty, Source, Name, I);
|
|
I->replaceAllUsesWith(MI);
|
|
|
|
// If the old instruction was an invoke, add an unconditional branch
|
|
// before the invoke, which will become the new terminator.
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(I))
|
|
new BranchInst(II->getNormalDest(), I);
|
|
|
|
// Delete the old call site
|
|
MI->getParent()->getInstList().erase(I);
|
|
Changed = true;
|
|
++NumRaised;
|
|
}
|
|
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(U)) {
|
|
Users.insert(Users.end(), GV->use_begin(), GV->use_end());
|
|
EqPointers.push_back(GV);
|
|
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(U)) {
|
|
if (CE->isCast()) {
|
|
Users.insert(Users.end(), CE->use_begin(), CE->use_end());
|
|
EqPointers.push_back(CE);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Next, process all free calls...
|
|
if (FreeFunc) {
|
|
std::vector<User*> Users(FreeFunc->use_begin(), FreeFunc->use_end());
|
|
std::vector<Value*> EqPointers; // Values equal to FreeFunc
|
|
|
|
while (!Users.empty()) {
|
|
User *U = Users.back();
|
|
Users.pop_back();
|
|
|
|
if (Instruction *I = dyn_cast<Instruction>(U)) {
|
|
CallSite CS = CallSite::get(I);
|
|
if (CS.getInstruction() && CS.arg_begin() != CS.arg_end() &&
|
|
(CS.getCalledFunction() == FreeFunc ||
|
|
std::find(EqPointers.begin(), EqPointers.end(),
|
|
CS.getCalledValue()) != EqPointers.end())) {
|
|
|
|
// If no prototype was provided for free, we may need to cast the
|
|
// source pointer. This should be really uncommon, but it's necessary
|
|
// just in case we are dealing with weird code like this:
|
|
// free((long)ptr);
|
|
//
|
|
Value *Source = *CS.arg_begin();
|
|
if (!isa<PointerType>(Source->getType()))
|
|
Source = new IntToPtrInst(Source, PointerType::get(Type::Int8Ty),
|
|
"FreePtrCast", I);
|
|
new FreeInst(Source, I);
|
|
|
|
// If the old instruction was an invoke, add an unconditional branch
|
|
// before the invoke, which will become the new terminator.
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(I))
|
|
new BranchInst(II->getNormalDest(), I);
|
|
|
|
// Delete the old call site
|
|
if (I->getType() != Type::VoidTy)
|
|
I->replaceAllUsesWith(UndefValue::get(I->getType()));
|
|
I->eraseFromParent();
|
|
Changed = true;
|
|
++NumRaised;
|
|
}
|
|
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(U)) {
|
|
Users.insert(Users.end(), GV->use_begin(), GV->use_end());
|
|
EqPointers.push_back(GV);
|
|
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(U)) {
|
|
if (CE->isCast()) {
|
|
Users.insert(Users.end(), CE->use_begin(), CE->use_end());
|
|
EqPointers.push_back(CE);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return Changed;
|
|
}
|