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llvm-6502/lib/ExecutionEngine/Interpreter/Execution.cpp
Jeff Cohen 8c9191c644 The interpreter assumes that the caller of runFunction() must be lli, and 
therefore the function being called must be a main() returning an int.  The
consequences when these assumptions are false are not good, so don't assume
them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26031 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-07 05:29:44 +00:00

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//===-- Execution.cpp - Implement code to simulate the program ------------===//
//
// 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 contains the actual instruction interpreter.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "interpreter"
#include "Interpreter.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
#include "llvm/CodeGen/IntrinsicLowering.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Debug.h"
#include <cmath> // For fmod
using namespace llvm;
namespace {
Statistic<> NumDynamicInsts("lli", "Number of dynamic instructions executed");
Interpreter *TheEE = 0;
}
//===----------------------------------------------------------------------===//
// Value Manipulation code
//===----------------------------------------------------------------------===//
static GenericValue executeAddInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSubInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeMulInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeRemInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeDivInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeAndInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeOrInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeXorInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetEQInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetNEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetLTInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetGTInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetLEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSetGEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeShlInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeShrInst(GenericValue Src1, GenericValue Src2,
const Type *Ty);
static GenericValue executeSelectInst(GenericValue Src1, GenericValue Src2,
GenericValue Src3);
GenericValue Interpreter::getConstantExprValue (ConstantExpr *CE,
ExecutionContext &SF) {
switch (CE->getOpcode()) {
case Instruction::Cast:
return executeCastOperation(CE->getOperand(0), CE->getType(), SF);
case Instruction::GetElementPtr:
return executeGEPOperation(CE->getOperand(0), gep_type_begin(CE),
gep_type_end(CE), SF);
case Instruction::Add:
return executeAddInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Sub:
return executeSubInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Mul:
return executeMulInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Div:
return executeDivInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Rem:
return executeRemInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::And:
return executeAndInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Or:
return executeOrInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Xor:
return executeXorInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetEQ:
return executeSetEQInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetNE:
return executeSetNEInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetLE:
return executeSetLEInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetGE:
return executeSetGEInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetLT:
return executeSetLTInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::SetGT:
return executeSetGTInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Shl:
return executeShlInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Shr:
return executeShrInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
CE->getOperand(0)->getType());
case Instruction::Select:
return executeSelectInst(getOperandValue(CE->getOperand(0), SF),
getOperandValue(CE->getOperand(1), SF),
getOperandValue(CE->getOperand(2), SF));
default:
std::cerr << "Unhandled ConstantExpr: " << *CE << "\n";
abort();
return GenericValue();
}
}
GenericValue Interpreter::getOperandValue(Value *V, ExecutionContext &SF) {
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
return getConstantExprValue(CE, SF);
} else if (Constant *CPV = dyn_cast<Constant>(V)) {
return getConstantValue(CPV);
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
return PTOGV(getPointerToGlobal(GV));
} else {
return SF.Values[V];
}
}
static void SetValue(Value *V, GenericValue Val, ExecutionContext &SF) {
SF.Values[V] = Val;
}
void Interpreter::initializeExecutionEngine() {
TheEE = this;
}
//===----------------------------------------------------------------------===//
// Binary Instruction Implementations
//===----------------------------------------------------------------------===//
#define IMPLEMENT_BINARY_OPERATOR(OP, TY) \
case Type::TY##TyID: Dest.TY##Val = Src1.TY##Val OP Src2.TY##Val; break
static GenericValue executeAddInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(+, UByte);
IMPLEMENT_BINARY_OPERATOR(+, SByte);
IMPLEMENT_BINARY_OPERATOR(+, UShort);
IMPLEMENT_BINARY_OPERATOR(+, Short);
IMPLEMENT_BINARY_OPERATOR(+, UInt);
IMPLEMENT_BINARY_OPERATOR(+, Int);
IMPLEMENT_BINARY_OPERATOR(+, ULong);
IMPLEMENT_BINARY_OPERATOR(+, Long);
IMPLEMENT_BINARY_OPERATOR(+, Float);
IMPLEMENT_BINARY_OPERATOR(+, Double);
default:
std::cout << "Unhandled type for Add instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSubInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(-, UByte);
IMPLEMENT_BINARY_OPERATOR(-, SByte);
IMPLEMENT_BINARY_OPERATOR(-, UShort);
IMPLEMENT_BINARY_OPERATOR(-, Short);
IMPLEMENT_BINARY_OPERATOR(-, UInt);
IMPLEMENT_BINARY_OPERATOR(-, Int);
IMPLEMENT_BINARY_OPERATOR(-, ULong);
IMPLEMENT_BINARY_OPERATOR(-, Long);
IMPLEMENT_BINARY_OPERATOR(-, Float);
IMPLEMENT_BINARY_OPERATOR(-, Double);
default:
std::cout << "Unhandled type for Sub instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeMulInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(*, UByte);
IMPLEMENT_BINARY_OPERATOR(*, SByte);
IMPLEMENT_BINARY_OPERATOR(*, UShort);
IMPLEMENT_BINARY_OPERATOR(*, Short);
IMPLEMENT_BINARY_OPERATOR(*, UInt);
IMPLEMENT_BINARY_OPERATOR(*, Int);
IMPLEMENT_BINARY_OPERATOR(*, ULong);
IMPLEMENT_BINARY_OPERATOR(*, Long);
IMPLEMENT_BINARY_OPERATOR(*, Float);
IMPLEMENT_BINARY_OPERATOR(*, Double);
default:
std::cout << "Unhandled type for Mul instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeDivInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(/, UByte);
IMPLEMENT_BINARY_OPERATOR(/, SByte);
IMPLEMENT_BINARY_OPERATOR(/, UShort);
IMPLEMENT_BINARY_OPERATOR(/, Short);
IMPLEMENT_BINARY_OPERATOR(/, UInt);
IMPLEMENT_BINARY_OPERATOR(/, Int);
IMPLEMENT_BINARY_OPERATOR(/, ULong);
IMPLEMENT_BINARY_OPERATOR(/, Long);
IMPLEMENT_BINARY_OPERATOR(/, Float);
IMPLEMENT_BINARY_OPERATOR(/, Double);
default:
std::cout << "Unhandled type for Div instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeRemInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(%, UByte);
IMPLEMENT_BINARY_OPERATOR(%, SByte);
IMPLEMENT_BINARY_OPERATOR(%, UShort);
IMPLEMENT_BINARY_OPERATOR(%, Short);
IMPLEMENT_BINARY_OPERATOR(%, UInt);
IMPLEMENT_BINARY_OPERATOR(%, Int);
IMPLEMENT_BINARY_OPERATOR(%, ULong);
IMPLEMENT_BINARY_OPERATOR(%, Long);
case Type::FloatTyID:
Dest.FloatVal = fmod(Src1.FloatVal, Src2.FloatVal);
break;
case Type::DoubleTyID:
Dest.DoubleVal = fmod(Src1.DoubleVal, Src2.DoubleVal);
break;
default:
std::cout << "Unhandled type for Rem instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeAndInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(&, Bool);
IMPLEMENT_BINARY_OPERATOR(&, UByte);
IMPLEMENT_BINARY_OPERATOR(&, SByte);
IMPLEMENT_BINARY_OPERATOR(&, UShort);
IMPLEMENT_BINARY_OPERATOR(&, Short);
IMPLEMENT_BINARY_OPERATOR(&, UInt);
IMPLEMENT_BINARY_OPERATOR(&, Int);
IMPLEMENT_BINARY_OPERATOR(&, ULong);
IMPLEMENT_BINARY_OPERATOR(&, Long);
default:
std::cout << "Unhandled type for And instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeOrInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(|, Bool);
IMPLEMENT_BINARY_OPERATOR(|, UByte);
IMPLEMENT_BINARY_OPERATOR(|, SByte);
IMPLEMENT_BINARY_OPERATOR(|, UShort);
IMPLEMENT_BINARY_OPERATOR(|, Short);
IMPLEMENT_BINARY_OPERATOR(|, UInt);
IMPLEMENT_BINARY_OPERATOR(|, Int);
IMPLEMENT_BINARY_OPERATOR(|, ULong);
IMPLEMENT_BINARY_OPERATOR(|, Long);
default:
std::cout << "Unhandled type for Or instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeXorInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_BINARY_OPERATOR(^, Bool);
IMPLEMENT_BINARY_OPERATOR(^, UByte);
IMPLEMENT_BINARY_OPERATOR(^, SByte);
IMPLEMENT_BINARY_OPERATOR(^, UShort);
IMPLEMENT_BINARY_OPERATOR(^, Short);
IMPLEMENT_BINARY_OPERATOR(^, UInt);
IMPLEMENT_BINARY_OPERATOR(^, Int);
IMPLEMENT_BINARY_OPERATOR(^, ULong);
IMPLEMENT_BINARY_OPERATOR(^, Long);
default:
std::cout << "Unhandled type for Xor instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
#define IMPLEMENT_SETCC(OP, TY) \
case Type::TY##TyID: Dest.BoolVal = Src1.TY##Val OP Src2.TY##Val; break
// Handle pointers specially because they must be compared with only as much
// width as the host has. We _do not_ want to be comparing 64 bit values when
// running on a 32-bit target, otherwise the upper 32 bits might mess up
// comparisons if they contain garbage.
#define IMPLEMENT_POINTERSETCC(OP) \
case Type::PointerTyID: \
Dest.BoolVal = (void*)(intptr_t)Src1.PointerVal OP \
(void*)(intptr_t)Src2.PointerVal; break
static GenericValue executeSetEQInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(==, UByte);
IMPLEMENT_SETCC(==, SByte);
IMPLEMENT_SETCC(==, UShort);
IMPLEMENT_SETCC(==, Short);
IMPLEMENT_SETCC(==, UInt);
IMPLEMENT_SETCC(==, Int);
IMPLEMENT_SETCC(==, ULong);
IMPLEMENT_SETCC(==, Long);
IMPLEMENT_SETCC(==, Float);
IMPLEMENT_SETCC(==, Double);
IMPLEMENT_POINTERSETCC(==);
default:
std::cout << "Unhandled type for SetEQ instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSetNEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(!=, UByte);
IMPLEMENT_SETCC(!=, SByte);
IMPLEMENT_SETCC(!=, UShort);
IMPLEMENT_SETCC(!=, Short);
IMPLEMENT_SETCC(!=, UInt);
IMPLEMENT_SETCC(!=, Int);
IMPLEMENT_SETCC(!=, ULong);
IMPLEMENT_SETCC(!=, Long);
IMPLEMENT_SETCC(!=, Float);
IMPLEMENT_SETCC(!=, Double);
IMPLEMENT_POINTERSETCC(!=);
default:
std::cout << "Unhandled type for SetNE instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSetLEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(<=, UByte);
IMPLEMENT_SETCC(<=, SByte);
IMPLEMENT_SETCC(<=, UShort);
IMPLEMENT_SETCC(<=, Short);
IMPLEMENT_SETCC(<=, UInt);
IMPLEMENT_SETCC(<=, Int);
IMPLEMENT_SETCC(<=, ULong);
IMPLEMENT_SETCC(<=, Long);
IMPLEMENT_SETCC(<=, Float);
IMPLEMENT_SETCC(<=, Double);
IMPLEMENT_POINTERSETCC(<=);
default:
std::cout << "Unhandled type for SetLE instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSetGEInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(>=, UByte);
IMPLEMENT_SETCC(>=, SByte);
IMPLEMENT_SETCC(>=, UShort);
IMPLEMENT_SETCC(>=, Short);
IMPLEMENT_SETCC(>=, UInt);
IMPLEMENT_SETCC(>=, Int);
IMPLEMENT_SETCC(>=, ULong);
IMPLEMENT_SETCC(>=, Long);
IMPLEMENT_SETCC(>=, Float);
IMPLEMENT_SETCC(>=, Double);
IMPLEMENT_POINTERSETCC(>=);
default:
std::cout << "Unhandled type for SetGE instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSetLTInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(<, UByte);
IMPLEMENT_SETCC(<, SByte);
IMPLEMENT_SETCC(<, UShort);
IMPLEMENT_SETCC(<, Short);
IMPLEMENT_SETCC(<, UInt);
IMPLEMENT_SETCC(<, Int);
IMPLEMENT_SETCC(<, ULong);
IMPLEMENT_SETCC(<, Long);
IMPLEMENT_SETCC(<, Float);
IMPLEMENT_SETCC(<, Double);
IMPLEMENT_POINTERSETCC(<);
default:
std::cout << "Unhandled type for SetLT instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
static GenericValue executeSetGTInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SETCC(>, UByte);
IMPLEMENT_SETCC(>, SByte);
IMPLEMENT_SETCC(>, UShort);
IMPLEMENT_SETCC(>, Short);
IMPLEMENT_SETCC(>, UInt);
IMPLEMENT_SETCC(>, Int);
IMPLEMENT_SETCC(>, ULong);
IMPLEMENT_SETCC(>, Long);
IMPLEMENT_SETCC(>, Float);
IMPLEMENT_SETCC(>, Double);
IMPLEMENT_POINTERSETCC(>);
default:
std::cout << "Unhandled type for SetGT instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
void Interpreter::visitBinaryOperator(BinaryOperator &I) {
ExecutionContext &SF = ECStack.back();
const Type *Ty = I.getOperand(0)->getType();
GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
GenericValue R; // Result
switch (I.getOpcode()) {
case Instruction::Add: R = executeAddInst (Src1, Src2, Ty); break;
case Instruction::Sub: R = executeSubInst (Src1, Src2, Ty); break;
case Instruction::Mul: R = executeMulInst (Src1, Src2, Ty); break;
case Instruction::Div: R = executeDivInst (Src1, Src2, Ty); break;
case Instruction::Rem: R = executeRemInst (Src1, Src2, Ty); break;
case Instruction::And: R = executeAndInst (Src1, Src2, Ty); break;
case Instruction::Or: R = executeOrInst (Src1, Src2, Ty); break;
case Instruction::Xor: R = executeXorInst (Src1, Src2, Ty); break;
case Instruction::SetEQ: R = executeSetEQInst(Src1, Src2, Ty); break;
case Instruction::SetNE: R = executeSetNEInst(Src1, Src2, Ty); break;
case Instruction::SetLE: R = executeSetLEInst(Src1, Src2, Ty); break;
case Instruction::SetGE: R = executeSetGEInst(Src1, Src2, Ty); break;
case Instruction::SetLT: R = executeSetLTInst(Src1, Src2, Ty); break;
case Instruction::SetGT: R = executeSetGTInst(Src1, Src2, Ty); break;
default:
std::cout << "Don't know how to handle this binary operator!\n-->" << I;
abort();
}
SetValue(&I, R, SF);
}
static GenericValue executeSelectInst(GenericValue Src1, GenericValue Src2,
GenericValue Src3) {
return Src1.BoolVal ? Src2 : Src3;
}
void Interpreter::visitSelectInst(SelectInst &I) {
ExecutionContext &SF = ECStack.back();
GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
GenericValue Src3 = getOperandValue(I.getOperand(2), SF);
GenericValue R = executeSelectInst(Src1, Src2, Src3);
SetValue(&I, R, SF);
}
//===----------------------------------------------------------------------===//
// Terminator Instruction Implementations
//===----------------------------------------------------------------------===//
void Interpreter::exitCalled(GenericValue GV) {
// runAtExitHandlers() assumes there are no stack frames, but
// if exit() was called, then it had a stack frame. Blow away
// the stack before interpreting atexit handlers.
ECStack.clear ();
runAtExitHandlers ();
exit (GV.IntVal);
}
/// Pop the last stack frame off of ECStack and then copy the result
/// back into the result variable if we are not returning void. The
/// result variable may be the ExitValue, or the Value of the calling
/// CallInst if there was a previous stack frame. This method may
/// invalidate any ECStack iterators you have. This method also takes
/// care of switching to the normal destination BB, if we are returning
/// from an invoke.
///
void Interpreter::popStackAndReturnValueToCaller (const Type *RetTy,
GenericValue Result) {
// Pop the current stack frame.
ECStack.pop_back();
if (ECStack.empty()) { // Finished main. Put result into exit code...
if (RetTy && RetTy->isIntegral()) { // Nonvoid return type?
ExitValue = Result; // Capture the exit value of the program
} else {
memset(&ExitValue, 0, sizeof(ExitValue));
}
} else {
// If we have a previous stack frame, and we have a previous call,
// fill in the return value...
ExecutionContext &CallingSF = ECStack.back();
if (Instruction *I = CallingSF.Caller.getInstruction()) {
if (CallingSF.Caller.getType() != Type::VoidTy) // Save result...
SetValue(I, Result, CallingSF);
if (InvokeInst *II = dyn_cast<InvokeInst> (I))
SwitchToNewBasicBlock (II->getNormalDest (), CallingSF);
CallingSF.Caller = CallSite(); // We returned from the call...
}
}
}
void Interpreter::visitReturnInst(ReturnInst &I) {
ExecutionContext &SF = ECStack.back();
const Type *RetTy = Type::VoidTy;
GenericValue Result;
// Save away the return value... (if we are not 'ret void')
if (I.getNumOperands()) {
RetTy = I.getReturnValue()->getType();
Result = getOperandValue(I.getReturnValue(), SF);
}
popStackAndReturnValueToCaller(RetTy, Result);
}
void Interpreter::visitUnwindInst(UnwindInst &I) {
// Unwind stack
Instruction *Inst;
do {
ECStack.pop_back ();
if (ECStack.empty ())
abort ();
Inst = ECStack.back ().Caller.getInstruction ();
} while (!(Inst && isa<InvokeInst> (Inst)));
// Return from invoke
ExecutionContext &InvokingSF = ECStack.back ();
InvokingSF.Caller = CallSite ();
// Go to exceptional destination BB of invoke instruction
SwitchToNewBasicBlock(cast<InvokeInst>(Inst)->getUnwindDest(), InvokingSF);
}
void Interpreter::visitUnreachableInst(UnreachableInst &I) {
std::cerr << "ERROR: Program executed an 'unreachable' instruction!\n";
abort();
}
void Interpreter::visitBranchInst(BranchInst &I) {
ExecutionContext &SF = ECStack.back();
BasicBlock *Dest;
Dest = I.getSuccessor(0); // Uncond branches have a fixed dest...
if (!I.isUnconditional()) {
Value *Cond = I.getCondition();
if (getOperandValue(Cond, SF).BoolVal == 0) // If false cond...
Dest = I.getSuccessor(1);
}
SwitchToNewBasicBlock(Dest, SF);
}
void Interpreter::visitSwitchInst(SwitchInst &I) {
ExecutionContext &SF = ECStack.back();
GenericValue CondVal = getOperandValue(I.getOperand(0), SF);
const Type *ElTy = I.getOperand(0)->getType();
// Check to see if any of the cases match...
BasicBlock *Dest = 0;
for (unsigned i = 2, e = I.getNumOperands(); i != e; i += 2)
if (executeSetEQInst(CondVal,
getOperandValue(I.getOperand(i), SF), ElTy).BoolVal) {
Dest = cast<BasicBlock>(I.getOperand(i+1));
break;
}
if (!Dest) Dest = I.getDefaultDest(); // No cases matched: use default
SwitchToNewBasicBlock(Dest, SF);
}
// SwitchToNewBasicBlock - This method is used to jump to a new basic block.
// This function handles the actual updating of block and instruction iterators
// as well as execution of all of the PHI nodes in the destination block.
//
// This method does this because all of the PHI nodes must be executed
// atomically, reading their inputs before any of the results are updated. Not
// doing this can cause problems if the PHI nodes depend on other PHI nodes for
// their inputs. If the input PHI node is updated before it is read, incorrect
// results can happen. Thus we use a two phase approach.
//
void Interpreter::SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF){
BasicBlock *PrevBB = SF.CurBB; // Remember where we came from...
SF.CurBB = Dest; // Update CurBB to branch destination
SF.CurInst = SF.CurBB->begin(); // Update new instruction ptr...
if (!isa<PHINode>(SF.CurInst)) return; // Nothing fancy to do
// Loop over all of the PHI nodes in the current block, reading their inputs.
std::vector<GenericValue> ResultValues;
for (; PHINode *PN = dyn_cast<PHINode>(SF.CurInst); ++SF.CurInst) {
// Search for the value corresponding to this previous bb...
int i = PN->getBasicBlockIndex(PrevBB);
assert(i != -1 && "PHINode doesn't contain entry for predecessor??");
Value *IncomingValue = PN->getIncomingValue(i);
// Save the incoming value for this PHI node...
ResultValues.push_back(getOperandValue(IncomingValue, SF));
}
// Now loop over all of the PHI nodes setting their values...
SF.CurInst = SF.CurBB->begin();
for (unsigned i = 0; isa<PHINode>(SF.CurInst); ++SF.CurInst, ++i) {
PHINode *PN = cast<PHINode>(SF.CurInst);
SetValue(PN, ResultValues[i], SF);
}
}
//===----------------------------------------------------------------------===//
// Memory Instruction Implementations
//===----------------------------------------------------------------------===//
void Interpreter::visitAllocationInst(AllocationInst &I) {
ExecutionContext &SF = ECStack.back();
const Type *Ty = I.getType()->getElementType(); // Type to be allocated
// Get the number of elements being allocated by the array...
unsigned NumElements = getOperandValue(I.getOperand(0), SF).UIntVal;
// Allocate enough memory to hold the type...
void *Memory = malloc(NumElements * (size_t)TD.getTypeSize(Ty));
GenericValue Result = PTOGV(Memory);
assert(Result.PointerVal != 0 && "Null pointer returned by malloc!");
SetValue(&I, Result, SF);
if (I.getOpcode() == Instruction::Alloca)
ECStack.back().Allocas.add(Memory);
}
void Interpreter::visitFreeInst(FreeInst &I) {
ExecutionContext &SF = ECStack.back();
assert(isa<PointerType>(I.getOperand(0)->getType()) && "Freeing nonptr?");
GenericValue Value = getOperandValue(I.getOperand(0), SF);
// TODO: Check to make sure memory is allocated
free(GVTOP(Value)); // Free memory
}
// getElementOffset - The workhorse for getelementptr.
//
GenericValue Interpreter::executeGEPOperation(Value *Ptr, gep_type_iterator I,
gep_type_iterator E,
ExecutionContext &SF) {
assert(isa<PointerType>(Ptr->getType()) &&
"Cannot getElementOffset of a nonpointer type!");
PointerTy Total = 0;
for (; I != E; ++I) {
if (const StructType *STy = dyn_cast<StructType>(*I)) {
const StructLayout *SLO = TD.getStructLayout(STy);
const ConstantUInt *CPU = cast<ConstantUInt>(I.getOperand());
unsigned Index = unsigned(CPU->getValue());
Total += (PointerTy)SLO->MemberOffsets[Index];
} else {
const SequentialType *ST = cast<SequentialType>(*I);
// Get the index number for the array... which must be long type...
GenericValue IdxGV = getOperandValue(I.getOperand(), SF);
uint64_t Idx;
switch (I.getOperand()->getType()->getTypeID()) {
default: assert(0 && "Illegal getelementptr index for sequential type!");
case Type::SByteTyID: Idx = IdxGV.SByteVal; break;
case Type::ShortTyID: Idx = IdxGV.ShortVal; break;
case Type::IntTyID: Idx = IdxGV.IntVal; break;
case Type::LongTyID: Idx = IdxGV.LongVal; break;
case Type::UByteTyID: Idx = IdxGV.UByteVal; break;
case Type::UShortTyID: Idx = IdxGV.UShortVal; break;
case Type::UIntTyID: Idx = IdxGV.UIntVal; break;
case Type::ULongTyID: Idx = IdxGV.ULongVal; break;
}
Total += PointerTy(TD.getTypeSize(ST->getElementType())*Idx);
}
}
GenericValue Result;
Result.PointerVal = getOperandValue(Ptr, SF).PointerVal + Total;
return Result;
}
void Interpreter::visitGetElementPtrInst(GetElementPtrInst &I) {
ExecutionContext &SF = ECStack.back();
SetValue(&I, TheEE->executeGEPOperation(I.getPointerOperand(),
gep_type_begin(I), gep_type_end(I), SF), SF);
}
void Interpreter::visitLoadInst(LoadInst &I) {
ExecutionContext &SF = ECStack.back();
GenericValue SRC = getOperandValue(I.getPointerOperand(), SF);
GenericValue *Ptr = (GenericValue*)GVTOP(SRC);
GenericValue Result = LoadValueFromMemory(Ptr, I.getType());
SetValue(&I, Result, SF);
}
void Interpreter::visitStoreInst(StoreInst &I) {
ExecutionContext &SF = ECStack.back();
GenericValue Val = getOperandValue(I.getOperand(0), SF);
GenericValue SRC = getOperandValue(I.getPointerOperand(), SF);
StoreValueToMemory(Val, (GenericValue *)GVTOP(SRC),
I.getOperand(0)->getType());
}
//===----------------------------------------------------------------------===//
// Miscellaneous Instruction Implementations
//===----------------------------------------------------------------------===//
void Interpreter::visitCallSite(CallSite CS) {
ExecutionContext &SF = ECStack.back();
// Check to see if this is an intrinsic function call...
if (Function *F = CS.getCalledFunction())
if (F->isExternal ())
switch (F->getIntrinsicID()) {
case Intrinsic::not_intrinsic:
break;
case Intrinsic::vastart: { // va_start
GenericValue ArgIndex;
ArgIndex.UIntPairVal.first = ECStack.size() - 1;
ArgIndex.UIntPairVal.second = 0;
SetValue(CS.getInstruction(), ArgIndex, SF);
return;
}
case Intrinsic::vaend: // va_end is a noop for the interpreter
return;
case Intrinsic::vacopy: // va_copy: dest = src
SetValue(CS.getInstruction(), getOperandValue(*CS.arg_begin(), SF), SF);
return;
default:
// If it is an unknown intrinsic function, use the intrinsic lowering
// class to transform it into hopefully tasty LLVM code.
//
Instruction *Prev = CS.getInstruction()->getPrev();
BasicBlock *Parent = CS.getInstruction()->getParent();
IL->LowerIntrinsicCall(cast<CallInst>(CS.getInstruction()));
// Restore the CurInst pointer to the first instruction newly inserted, if
// any.
if (!Prev) {
SF.CurInst = Parent->begin();
} else {
SF.CurInst = Prev;
++SF.CurInst;
}
return;
}
SF.Caller = CS;
std::vector<GenericValue> ArgVals;
const unsigned NumArgs = SF.Caller.arg_size();
ArgVals.reserve(NumArgs);
for (CallSite::arg_iterator i = SF.Caller.arg_begin(),
e = SF.Caller.arg_end(); i != e; ++i) {
Value *V = *i;
ArgVals.push_back(getOperandValue(V, SF));
// Promote all integral types whose size is < sizeof(int) into ints. We do
// this by zero or sign extending the value as appropriate according to the
// source type.
const Type *Ty = V->getType();
if (Ty->isIntegral() && Ty->getPrimitiveSize() < 4) {
if (Ty == Type::ShortTy)
ArgVals.back().IntVal = ArgVals.back().ShortVal;
else if (Ty == Type::UShortTy)
ArgVals.back().UIntVal = ArgVals.back().UShortVal;
else if (Ty == Type::SByteTy)
ArgVals.back().IntVal = ArgVals.back().SByteVal;
else if (Ty == Type::UByteTy)
ArgVals.back().UIntVal = ArgVals.back().UByteVal;
else if (Ty == Type::BoolTy)
ArgVals.back().UIntVal = ArgVals.back().BoolVal;
else
assert(0 && "Unknown type!");
}
}
// To handle indirect calls, we must get the pointer value from the argument
// and treat it as a function pointer.
GenericValue SRC = getOperandValue(SF.Caller.getCalledValue(), SF);
callFunction((Function*)GVTOP(SRC), ArgVals);
}
#define IMPLEMENT_SHIFT(OP, TY) \
case Type::TY##TyID: Dest.TY##Val = Src1.TY##Val OP Src2.UByteVal; break
static GenericValue executeShlInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SHIFT(<<, UByte);
IMPLEMENT_SHIFT(<<, SByte);
IMPLEMENT_SHIFT(<<, UShort);
IMPLEMENT_SHIFT(<<, Short);
IMPLEMENT_SHIFT(<<, UInt);
IMPLEMENT_SHIFT(<<, Int);
IMPLEMENT_SHIFT(<<, ULong);
IMPLEMENT_SHIFT(<<, Long);
default:
std::cout << "Unhandled type for Shl instruction: " << *Ty << "\n";
}
return Dest;
}
static GenericValue executeShrInst(GenericValue Src1, GenericValue Src2,
const Type *Ty) {
GenericValue Dest;
switch (Ty->getTypeID()) {
IMPLEMENT_SHIFT(>>, UByte);
IMPLEMENT_SHIFT(>>, SByte);
IMPLEMENT_SHIFT(>>, UShort);
IMPLEMENT_SHIFT(>>, Short);
IMPLEMENT_SHIFT(>>, UInt);
IMPLEMENT_SHIFT(>>, Int);
IMPLEMENT_SHIFT(>>, ULong);
IMPLEMENT_SHIFT(>>, Long);
default:
std::cout << "Unhandled type for Shr instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
void Interpreter::visitShl(ShiftInst &I) {
ExecutionContext &SF = ECStack.back();
const Type *Ty = I.getOperand(0)->getType();
GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
GenericValue Dest;
Dest = executeShlInst (Src1, Src2, Ty);
SetValue(&I, Dest, SF);
}
void Interpreter::visitShr(ShiftInst &I) {
ExecutionContext &SF = ECStack.back();
const Type *Ty = I.getOperand(0)->getType();
GenericValue Src1 = getOperandValue(I.getOperand(0), SF);
GenericValue Src2 = getOperandValue(I.getOperand(1), SF);
GenericValue Dest;
Dest = executeShrInst (Src1, Src2, Ty);
SetValue(&I, Dest, SF);
}
#define IMPLEMENT_CAST(DTY, DCTY, STY) \
case Type::STY##TyID: Dest.DTY##Val = DCTY Src.STY##Val; break;
#define IMPLEMENT_CAST_CASE_START(DESTTY, DESTCTY) \
case Type::DESTTY##TyID: \
switch (SrcTy->getTypeID()) { \
IMPLEMENT_CAST(DESTTY, DESTCTY, Bool); \
IMPLEMENT_CAST(DESTTY, DESTCTY, UByte); \
IMPLEMENT_CAST(DESTTY, DESTCTY, SByte); \
IMPLEMENT_CAST(DESTTY, DESTCTY, UShort); \
IMPLEMENT_CAST(DESTTY, DESTCTY, Short); \
IMPLEMENT_CAST(DESTTY, DESTCTY, UInt); \
IMPLEMENT_CAST(DESTTY, DESTCTY, Int); \
IMPLEMENT_CAST(DESTTY, DESTCTY, ULong); \
IMPLEMENT_CAST(DESTTY, DESTCTY, Long); \
IMPLEMENT_CAST(DESTTY, DESTCTY, Pointer);
#define IMPLEMENT_CAST_CASE_FP_IMP(DESTTY, DESTCTY) \
IMPLEMENT_CAST(DESTTY, DESTCTY, Float); \
IMPLEMENT_CAST(DESTTY, DESTCTY, Double)
#define IMPLEMENT_CAST_CASE_END() \
default: std::cout << "Unhandled cast: " << *SrcTy << " to " << *Ty << "\n"; \
abort(); \
} \
break
#define IMPLEMENT_CAST_CASE(DESTTY, DESTCTY) \
IMPLEMENT_CAST_CASE_START(DESTTY, DESTCTY); \
IMPLEMENT_CAST_CASE_FP_IMP(DESTTY, DESTCTY); \
IMPLEMENT_CAST_CASE_END()
GenericValue Interpreter::executeCastOperation(Value *SrcVal, const Type *Ty,
ExecutionContext &SF) {
const Type *SrcTy = SrcVal->getType();
GenericValue Dest, Src = getOperandValue(SrcVal, SF);
switch (Ty->getTypeID()) {
IMPLEMENT_CAST_CASE(UByte , (unsigned char));
IMPLEMENT_CAST_CASE(SByte , ( signed char));
IMPLEMENT_CAST_CASE(UShort , (unsigned short));
IMPLEMENT_CAST_CASE(Short , ( signed short));
IMPLEMENT_CAST_CASE(UInt , (unsigned int ));
IMPLEMENT_CAST_CASE(Int , ( signed int ));
IMPLEMENT_CAST_CASE(ULong , (uint64_t));
IMPLEMENT_CAST_CASE(Long , ( int64_t));
IMPLEMENT_CAST_CASE(Pointer, (PointerTy));
IMPLEMENT_CAST_CASE(Float , (float));
IMPLEMENT_CAST_CASE(Double , (double));
IMPLEMENT_CAST_CASE(Bool , (bool));
default:
std::cout << "Unhandled dest type for cast instruction: " << *Ty << "\n";
abort();
}
return Dest;
}
void Interpreter::visitCastInst(CastInst &I) {
ExecutionContext &SF = ECStack.back();
SetValue(&I, executeCastOperation(I.getOperand(0), I.getType(), SF), SF);
}
#define IMPLEMENT_VAARG(TY) \
case Type::TY##TyID: Dest.TY##Val = Src.TY##Val; break
void Interpreter::visitVAArgInst(VAArgInst &I) {
ExecutionContext &SF = ECStack.back();
// Get the incoming valist parameter. LLI treats the valist as a
// (ec-stack-depth var-arg-index) pair.
GenericValue VAList = getOperandValue(I.getOperand(0), SF);
GenericValue Dest;
GenericValue Src = ECStack[VAList.UIntPairVal.first]
.VarArgs[VAList.UIntPairVal.second];
const Type *Ty = I.getType();
switch (Ty->getTypeID()) {
IMPLEMENT_VAARG(UByte);
IMPLEMENT_VAARG(SByte);
IMPLEMENT_VAARG(UShort);
IMPLEMENT_VAARG(Short);
IMPLEMENT_VAARG(UInt);
IMPLEMENT_VAARG(Int);
IMPLEMENT_VAARG(ULong);
IMPLEMENT_VAARG(Long);
IMPLEMENT_VAARG(Pointer);
IMPLEMENT_VAARG(Float);
IMPLEMENT_VAARG(Double);
IMPLEMENT_VAARG(Bool);
default:
std::cout << "Unhandled dest type for vaarg instruction: " << *Ty << "\n";
abort();
}
// Set the Value of this Instruction.
SetValue(&I, Dest, SF);
// Move the pointer to the next vararg.
++VAList.UIntPairVal.second;
}
//===----------------------------------------------------------------------===//
// Dispatch and Execution Code
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
// callFunction - Execute the specified function...
//
void Interpreter::callFunction(Function *F,
const std::vector<GenericValue> &ArgVals) {
assert((ECStack.empty() || ECStack.back().Caller.getInstruction() == 0 ||
ECStack.back().Caller.arg_size() == ArgVals.size()) &&
"Incorrect number of arguments passed into function call!");
// Make a new stack frame... and fill it in.
ECStack.push_back(ExecutionContext());
ExecutionContext &StackFrame = ECStack.back();
StackFrame.CurFunction = F;
// Special handling for external functions.
if (F->isExternal()) {
GenericValue Result = callExternalFunction (F, ArgVals);
// Simulate a 'ret' instruction of the appropriate type.
popStackAndReturnValueToCaller (F->getReturnType (), Result);
return;
}
// Get pointers to first LLVM BB & Instruction in function.
StackFrame.CurBB = F->begin();
StackFrame.CurInst = StackFrame.CurBB->begin();
// Run through the function arguments and initialize their values...
assert((ArgVals.size() == F->arg_size() ||
(ArgVals.size() > F->arg_size() && F->getFunctionType()->isVarArg()))&&
"Invalid number of values passed to function invocation!");
// Handle non-varargs arguments...
unsigned i = 0;
for (Function::arg_iterator AI = F->arg_begin(), E = F->arg_end(); AI != E; ++AI, ++i)
SetValue(AI, ArgVals[i], StackFrame);
// Handle varargs arguments...
StackFrame.VarArgs.assign(ArgVals.begin()+i, ArgVals.end());
}
void Interpreter::run() {
while (!ECStack.empty()) {
// Interpret a single instruction & increment the "PC".
ExecutionContext &SF = ECStack.back(); // Current stack frame
Instruction &I = *SF.CurInst++; // Increment before execute
// Track the number of dynamic instructions executed.
++NumDynamicInsts;
DEBUG(std::cerr << "About to interpret: " << I);
visit(I); // Dispatch to one of the visit* methods...
}
}
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