New class for machine state

src/binary_translation/CMakeLists.txt

@@ -4,6 +4,7 @@ set(SRCS
 			ModuleGen.cpp
 			Disassembler.cpp
 			InstructionBlock.cpp
+			MachineState.cpp
 			
 			Instructions/Instruction.cpp
 			Instructions/DataProcessing.cpp
@@ -13,6 +14,7 @@ set(HEADERS
 			ModuleGen.h
 			Disassembler.h
 			InstructionBlock.h
+			MachineState.h
 			
 			Instructions/Types.h
 			Instructions/Instruction.h

src/binary_translation/InstructionBlock.cpp

@@ -3,6 +3,7 @@
 #include "Instructions/Instruction.h"
 #include <sstream>
 #include <iomanip>
+#include "MachineState.h"
 
 InstructionBlock::InstructionBlock(ModuleGen* module, Instruction* instruction)
     : module(module),
@@ -33,14 +34,12 @@ void InstructionBlock::GenerateCode()
 
 llvm::Value *InstructionBlock::Read(Register reg)
 {
-    auto ib = module->IrBuilder();
-    return ib->CreateAlignedLoad(module->GetRegisterPtr(reg), 4);
+    return module->Machine()->ReadRegiser(reg);
 }
 
 llvm::Value *InstructionBlock::Write(Register reg, llvm::Value *value)
 {
-    auto ib = module->IrBuilder();
-    return ib->CreateAlignedStore(value, module->GetRegisterPtr(reg), 4);
+    return module->Machine()->WriteRegiser(reg, value);
 }
 
 size_t InstructionBlock::Address()

src/binary_translation/MachineState.cpp

@@ -0,0 +1,55 @@
+#include "MachineState.h"
+#include "ModuleGen.h"
+#include "Instructions/Types.h"
+#include <llvm/IR/GlobalValue.h>
+#include <llvm/IR/Constants.h>
+#include <llvm/IR/LLVMContext.h>
+#include <llvm/IR/GlobalVariable.h>
+
+using namespace llvm;
+
+MachineState::MachineState(ModuleGen *module) : module(module)
+{
+}
+
+void MachineState::GenerateGlobals()
+{
+    auto registers_global_initializer = ConstantPointerNull::get(IntegerType::getInt32PtrTy(getGlobalContext()));
+    registers_global = new GlobalVariable(*module->Module(), registers_global_initializer->getType(),
+        false, GlobalValue::ExternalLinkage, registers_global_initializer, "Registers");
+
+    // Flags is stored internally as i1* indexed in multiples of 4
+    auto flags_global_initializer = ConstantPointerNull::get(IntegerType::getInt1PtrTy(getGlobalContext()));
+    flags_global = new GlobalVariable(*module->Module(), flags_global_initializer->getType(),
+        false, GlobalValue::ExternalLinkage, flags_global_initializer, "Flags");
+}
+
+Value* MachineState::ReadRegiser(Register reg)
+{
+    auto load = module->IrBuilder()->CreateLoad(GetRegisterPtr(reg));
+    return load;
+}
+
+Value* MachineState::WriteRegiser(Register reg, Value *value)
+{
+    auto store = module->IrBuilder()->CreateAlignedStore(value, GetRegisterPtr(reg), 4);
+    return store;
+}
+
+Value *MachineState::GetRegisterPtr(Register reg)
+{
+    Value *global;
+    unsigned index;
+    if (reg <= Register::PC)
+    {
+        global = registers_global;
+        index = static_cast<unsigned>(reg)-static_cast<unsigned>(Register::R0);
+    }
+    else
+    {
+        global = flags_global;
+        index = static_cast<unsigned>(reg)-static_cast<unsigned>(Register::N);
+    }
+    auto base = module->IrBuilder()->CreateAlignedLoad(global, 4);
+    return module->IrBuilder()->CreateConstInBoundsGEP1_32(base, index);
+}

src/binary_translation/MachineState.h

@@ -0,0 +1,41 @@
+
+enum class Register;
+class ModuleGen;
+
+namespace llvm
+{
+    class Value;
+    class GlobalVariable;
+}
+
+/*
+Contains all the machine state:
+    Registers, Flags, Memory
+*/
+class MachineState
+{
+public:
+    MachineState(ModuleGen *module);
+
+    void GenerateGlobals();
+    llvm::Value *ReadRegiser(Register reg);
+    llvm::Value *WriteRegiser(Register reg, llvm::Value *value);
+
+private:
+    // Returns the address of a register or a flag
+    llvm::Value *GetRegisterPtr(Register reg);
+
+    ModuleGen *module;
+
+    /*
+    * u32 *Registers;
+    *  The registers of the cpu
+    */
+    llvm::GlobalVariable *registers_global;
+    /*
+    * u32 *Flags;
+    *  The flags of the cpu
+    *  Orderered N, Z, C, V
+    */
+    llvm::GlobalVariable *flags_global;
+};

src/binary_translation/ModuleGen.cpp

@@ -8,6 +8,7 @@
 #include <llvm/IR/Function.h>
 #include <llvm/IR/GlobalVariable.h>
 #include <stack>
+#include "MachineState.h"
 
 using namespace llvm;
 
@@ -15,6 +16,7 @@ ModuleGen::ModuleGen(llvm::Module* module)
     : module(module)
 {
     ir_builder = make_unique<IRBuilder<>>(getGlobalContext());
+    machine = make_unique<MachineState>(this);
 }
 
 ModuleGen::~ModuleGen()
@@ -39,32 +41,9 @@ void ModuleGen::Run()
     GenerateBlockAddressArray();
 }
 
-Value *ModuleGen::GetRegisterPtr(Register reg)
-{
-    Value *global;
-    unsigned index;
-    if (reg <= Register::PC)
-    {
-        global = registers_global;
-        index = static_cast<unsigned>(reg)-static_cast<unsigned>(Register::R0);
-    }
-    else
-    {
-        global = flags_global;
-        index = static_cast<unsigned>(reg)-static_cast<unsigned>(Register::N);
-    }
-    auto base = ir_builder->CreateAlignedLoad(global, 4);
-    return ir_builder->CreateConstInBoundsGEP1_32(base, index);
-}
-
 void ModuleGen::GenerateGlobals()
 {
-    auto registers_global_initializer = ConstantPointerNull::get(IntegerType::getInt32PtrTy(getGlobalContext()));
-    registers_global = new GlobalVariable(*module, registers_global_initializer->getType(), false, GlobalValue::ExternalLinkage, registers_global_initializer, "Registers");
-
-    // Flags is stored internally as i1* indexed in multiples of 4
-    auto flags_global_initializer = ConstantPointerNull::get(IntegerType::getInt1PtrTy(getGlobalContext()));
-    flags_global = new GlobalVariable(*module, flags_global_initializer->getType(), false, GlobalValue::ExternalLinkage, flags_global_initializer, "Flags");
+    machine->GenerateGlobals();
 
     auto get_block_address_function_type = FunctionType::get(ir_builder->getInt8PtrTy(), ir_builder->getInt32Ty(), false);
     get_block_address_function = Function::Create(get_block_address_function_type, GlobalValue::PrivateLinkage, "GetBlockAddress", module);
@@ -146,7 +125,7 @@ void ModuleGen::GenerateCanRunFunction()
     auto basic_block = BasicBlock::Create(getGlobalContext(), "Entry", can_run_function);
 
     ir_builder->SetInsertPoint(basic_block);
-    auto block_address = ir_builder->CreateCall(get_block_address_function, ir_builder->CreateAlignedLoad(GetRegisterPtr(Register::PC), 4));
+    auto block_address = ir_builder->CreateCall(get_block_address_function, machine->ReadRegiser(Register::PC));
     ir_builder->CreateRet(ir_builder->CreateICmpNE(block_address, ConstantPointerNull::get(ir_builder->getInt8PtrTy())));
 }
 
@@ -178,7 +157,7 @@ void ModuleGen::GenerateRunFunction()
     ir_builder->CreateBr(run_function_re_entry);
 
     ir_builder->SetInsertPoint(run_function_re_entry);
-    auto block_address = ir_builder->CreateCall(get_block_address_function, ir_builder->CreateAlignedLoad(GetRegisterPtr(Register::PC), 4));
+    auto block_address = ir_builder->CreateCall(get_block_address_function, Machine()->ReadRegiser(Register::PC));
     auto block_present_pred = ir_builder->CreateICmpNE(block_address, ConstantPointerNull::get(ir_builder->getInt8PtrTy()));
     ir_builder->CreateCondBr(block_present_pred, block_present_basic_block, block_not_present_basic_block);
 
@@ -227,7 +206,7 @@ void ModuleGen::GenerateInstructionsTermination()
     for (auto &block : instruction_blocks)
     {
         ir_builder->SetInsertPoint(block->GetExitBasicBlock());
-        ir_builder->CreateAlignedStore(ir_builder->getInt32(block->Address() + 4), GetRegisterPtr(Register::PC), 4);
+        Machine()->WriteRegiser(Register::PC, ir_builder->getInt32(block->Address() + 4));
         ir_builder->CreateBr(run_function_re_entry);
     }
 }

src/binary_translation/ModuleGen.h

@@ -5,6 +5,7 @@
 enum class Register;
 
 class InstructionBlock;
+class MachineState;
 
 namespace llvm
 {
@@ -19,11 +20,10 @@ public:
 
     void Run();
 
-    // Returns the address of a register or a flag
-    llvm::Value *GetRegisterPtr(Register reg);
-
     llvm::IRBuilder<> *IrBuilder() { return ir_builder.get(); }
     llvm::Module *Module() { return module; }
+    MachineState *Machine() { return machine.get(); }
+
 private:
     // Generates the declarations of all the globals of the module
     void GenerateGlobals();
@@ -42,21 +42,11 @@ private:
     // Adds all the basic blocks of an instruction to the run function
     void AddInstructionsToRunFunction();
 
+    std::unique_ptr<MachineState> machine;
+
     std::unique_ptr<llvm::IRBuilder<>> ir_builder;
     llvm::Module *module;
 
-    /*
-     * u32 *Registers;
-     *  The registers of the cpu
-     */
-    llvm::GlobalVariable *registers_global;
-    /*
-     * u32 *Flags;
-     *  The flags of the cpu
-     *  Orderered N, Z, C, V
-     */
-    llvm::GlobalVariable *flags_global;
-
     size_t block_address_array_base;
     size_t block_address_array_size;
     /*