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expression.c
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#include "picoc.h"
/* whether evaluation is left to right for a given precedence level */
#define IS_LEFT_TO_RIGHT(p) ((p) != 2 && (p) != 3 && (p) != 14)
#define BRACKET_PRECEDENCE 20
#define IS_TYPE_TOKEN(t) ((t) >= TokenIntType && (t) <= TokenEnumType)
#ifdef DEBUG_EXPRESSIONS
#define debugf printf
#else
void debugf(char *Format, ...)
{
}
#endif
/* local prototypes */
enum OperatorOrder
{
OrderNone,
OrderPrefix,
OrderInfix,
OrderPostfix
};
/* a stack of expressions we use in evaluation */
struct ExpressionStack
{
struct ExpressionStack *Next; /* the next lower item on the stack */
struct Value *Val; /* the value for this stack node */
enum LexToken Op; /* the operator */
short unsigned int Precedence; /* the operator precedence of this node */
unsigned char Order; /* the evaluation order of this operator */
};
/* operator precedence definitions */
struct OpPrecedence
{
unsigned int PrefixPrecedence:4;
unsigned int PostfixPrecedence:4;
unsigned int InfixPrecedence:4;
char *Name;
};
/* NOTE: the order of this array must correspond exactly to the order of these tokens in enum LexToken */
static struct OpPrecedence OperatorPrecedence[] =
{
/* TokenNone, */ { 0, 0, 0, "none" },
/* TokenComma, */ { 0, 0, 0, "," },
/* TokenAssign, */ { 0, 0, 2, "=" }, /* TokenAddAssign, */ { 0, 0, 2, "+=" }, /* TokenSubtractAssign, */ { 0, 0, 2, "-=" },
/* TokenMultiplyAssign, */ { 0, 0, 2, "*=" }, /* TokenDivideAssign, */ { 0, 0, 2, "/=" }, /* TokenModulusAssign, */ { 0, 0, 2, "%=" },
/* TokenShiftLeftAssign, */ { 0, 0, 2, "<<=" }, /* TokenShiftRightAssign, */ { 0, 0, 2, ">>=" }, /* TokenArithmeticAndAssign, */ { 0, 0, 2, "&=" },
/* TokenArithmeticOrAssign, */ { 0, 0, 2, "|=" }, /* TokenArithmeticExorAssign, */ { 0, 0, 2, "^=" },
/* TokenQuestionMark, */ { 0, 0, 3, "?" }, /* TokenColon, */ { 0, 0, 3, ":" },
/* TokenLogicalOr, */ { 0, 0, 4, "||" },
/* TokenLogicalAnd, */ { 0, 0, 5, "&&" },
/* TokenArithmeticOr, */ { 0, 0, 6, "|" },
/* TokenArithmeticExor, */ { 0, 0, 7, "^" },
/* TokenAmpersand, */ { 14, 0, 8, "&" },
/* TokenEqual, */ { 0, 0, 9, "==" }, /* TokenNotEqual, */ { 0, 0, 9, "!=" },
/* TokenLessThan, */ { 0, 0, 10, "<" }, /* TokenGreaterThan, */ { 0, 0, 10, ">" }, /* TokenLessEqual, */ { 0, 0, 10, "<=" }, /* TokenGreaterEqual, */ { 0, 0, 10, ">=" },
/* TokenShiftLeft, */ { 0, 0, 11, "<<" }, /* TokenShiftRight, */ { 0, 0, 11, ">>" },
/* TokenPlus, */ { 14, 0, 12, "+" }, /* TokenMinus, */ { 14, 0, 12, "-" },
/* TokenAsterisk, */ { 14, 0, 13, "*" }, /* TokenSlash, */ { 0, 0, 13, "/" }, /* TokenModulus, */ { 0, 0, 13, "%" },
/* TokenIncrement, */ { 14, 15, 0, "++" }, /* TokenDecrement, */ { 14, 15, 0, "--" }, /* TokenUnaryNot, */ { 14, 0, 0, "!" }, /* TokenUnaryExor, */ { 14, 0, 0, "~" }, /* TokenSizeof, */ { 14, 0, 0, "sizeof" }, /* TokenCast, */ { 14, 0, 0, "cast" },
/* TokenLeftSquareBracket, */ { 0, 0, 15, "[" }, /* TokenRightSquareBracket, */ { 0, 15, 0, "]" }, /* TokenDot, */ { 0, 0, 15, "." }, /* TokenArrow, */ { 0, 0, 15, "->" },
/* TokenOpenBracket, */ { 15, 0, 0, "(" }, /* TokenCloseBracket, */ { 0, 15, 0, ")" }
};
void ExpressionParseFunctionCall(struct ParseState *Parser, struct ExpressionStack **StackTop, const char *FuncName);
#ifdef DEBUG_EXPRESSIONS
/* show the contents of the expression stack */
void ExpressionStackShow(struct ExpressionStack *StackTop)
{
printf("Expression stack [0x%lx,0x%lx]: ", (long)HeapStackTop, (long)StackTop);
while (StackTop != NULL)
{
if (StackTop->Order == OrderNone)
{
/* it's a value */
if (StackTop->Val->IsLValue)
printf("lvalue=");
else
printf("value=");
switch (StackTop->Val->Typ->Base)
{
case TypeVoid: printf("void"); break;
case TypeInt: printf("%d:int", StackTop->Val->Val->Integer); break;
case TypeShort: printf("%d:short", StackTop->Val->Val->ShortInteger); break;
case TypeChar: printf("%d:char", StackTop->Val->Val->Character); break;
case TypeFP: printf("%f:fp", StackTop->Val->Val->FP); break;
case TypeFunction: printf("%s:function", StackTop->Val->Val->Identifier); break;
case TypeMacro: printf("%s:macro", StackTop->Val->Val->Identifier); break;
case TypePointer:
if (StackTop->Val->Val->Pointer.Segment == NULL)
printf("ptr(NULL)");
else if (StackTop->Val->Typ->FromType->Base == TypeChar)
printf("\"%s\":string", (char *)StackTop->Val->Val->Pointer.Segment->Val->ArrayData + StackTop->Val->Val->Pointer.Offset);
else
printf("ptr(0x%lx,%d)", (long)StackTop->Val->Val->Pointer.Segment, StackTop->Val->Val->Pointer.Offset);
break;
case TypeArray: printf("array"); break;
case TypeStruct: printf("%s:struct", StackTop->Val->Val->Identifier); break;
case TypeUnion: printf("%s:union", StackTop->Val->Val->Identifier); break;
case TypeEnum: printf("%s:enum", StackTop->Val->Val->Identifier); break;
default: printf("unknown"); break;
}
printf("[0x%lx,0x%lx]", (long)StackTop, (long)StackTop->Val);
}
else
{
/* it's an operator */
printf("op='%s' %s %d", OperatorPrecedence[(int)StackTop->Op].Name,
(StackTop->Order == OrderPrefix) ? "prefix" : ((StackTop->Order == OrderPostfix) ? "postfix" : "infix"),
StackTop->Precedence);
printf("[0x%lx]", (long)StackTop);
}
StackTop = StackTop->Next;
if (StackTop != NULL)
printf(", ");
}
printf("\n");
}
#endif
int ExpressionCoerceInteger(struct Value *Val)
{
switch (Val->Typ->Base)
{
case TypeInt: return (int)Val->Val->Integer;
case TypeChar: return (int)Val->Val->Character;
case TypeShort: return (int)Val->Val->ShortInteger;
case TypeUnsignedInt: return (int)Val->Val->UnsignedInteger;
case TypeUnsignedShort: return (int)Val->Val->UnsignedShortInteger;
case TypePointer: return (int)Val->Val->NativePointer;
#ifndef NO_FP
case TypeFP: return (int)Val->Val->FP;
#endif
default: return 0;
}
}
unsigned int ExpressionCoerceUnsignedInteger(struct Value *Val)
{
switch (Val->Typ->Base)
{
case TypeInt: return (unsigned int)Val->Val->Integer;
case TypeChar: return (unsigned int)Val->Val->Character;
case TypeShort: return (unsigned int)Val->Val->ShortInteger;
case TypeUnsignedInt: return (unsigned int)Val->Val->UnsignedInteger;
case TypeUnsignedShort: return (unsigned int)Val->Val->UnsignedShortInteger;
case TypePointer: return (unsigned int)Val->Val->NativePointer;
#ifndef NO_FP
case TypeFP: return (unsigned int)Val->Val->FP;
#endif
default: return 0;
}
}
double ExpressionCoerceFP(struct Value *Val)
{
switch (Val->Typ->Base)
{
case TypeInt: return (double)Val->Val->Integer;
case TypeChar: return (double)Val->Val->Character;
case TypeShort: return (double)Val->Val->ShortInteger;
case TypeUnsignedInt: return (double)Val->Val->UnsignedInteger;
case TypeUnsignedShort: return (double)Val->Val->UnsignedShortInteger;
#ifndef NO_FP
case TypeFP: return (double)Val->Val->FP;
#endif
default: return 0;
}
}
/* assign an integer value */
int ExpressionAssignInt(struct ParseState *Parser, struct Value *DestValue, int FromInt, int After)
{
int Result;
if (!DestValue->IsLValue)
ProgramFail(Parser, "can't assign to this");
if (After)
Result = ExpressionCoerceInteger(DestValue);
else
Result = FromInt;
switch (DestValue->Typ->Base)
{
case TypeInt: DestValue->Val->Integer = FromInt; break;
case TypeShort: DestValue->Val->ShortInteger = (short)FromInt; break;
case TypeChar: DestValue->Val->Character = (unsigned char)FromInt; break;
case TypeUnsignedInt: DestValue->Val->UnsignedInteger = (unsigned int)FromInt; break;
case TypeUnsignedShort: DestValue->Val->UnsignedShortInteger = (unsigned short)FromInt; break;
default: break;
}
return Result;
}
#ifndef NO_FP
/* assign a floating point value */
double ExpressionAssignFP(struct ParseState *Parser, struct Value *DestValue, double FromFP)
{
if (!DestValue->IsLValue)
ProgramFail(Parser, "can't assign to this");
DestValue->Val->FP = FromFP;
return FromFP;
}
#endif
/* push a node on to the expression stack */
void ExpressionStackPushValueNode(struct ParseState *Parser, struct ExpressionStack **StackTop, struct Value *ValueLoc)
{
struct ExpressionStack *StackNode = VariableAlloc(Parser, sizeof(struct ExpressionStack), FALSE);
StackNode->Next = *StackTop;
StackNode->Val = ValueLoc;
*StackTop = StackNode;
#ifdef FANCY_ERROR_MESSAGES
StackNode->Line = Parser->Line;
StackNode->CharacterPos = Parser->CharacterPos;
#endif
#ifdef DEBUG_EXPRESSIONS
ExpressionStackShow(*StackTop);
#endif
}
/* push a blank value on to the expression stack by type */
struct Value *ExpressionStackPushValueByType(struct ParseState *Parser, struct ExpressionStack **StackTop, struct ValueType *PushType)
{
struct Value *ValueLoc = VariableAllocValueFromType(Parser, PushType, FALSE, NULL, FALSE);
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
return ValueLoc;
}
/* push a value on to the expression stack */
void ExpressionStackPushValue(struct ParseState *Parser, struct ExpressionStack **StackTop, struct Value *PushValue)
{
struct Value *ValueLoc = VariableAllocValueAndCopy(Parser, PushValue, FALSE);
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
}
void ExpressionStackPushLValue(struct ParseState *Parser, struct ExpressionStack **StackTop, struct Value *PushValue, int Offset)
{
struct Value *ValueLoc = VariableAllocValueShared(Parser, PushValue);
ValueLoc->Val = (void *)((char *)ValueLoc->Val + Offset);
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
}
void ExpressionStackPushDereference(struct ParseState *Parser, struct ExpressionStack **StackTop, struct Value *DereferenceValue)
{
struct Value *DerefVal;
int Offset;
struct ValueType *DerefType;
int DerefIsLValue;
void *DerefDataLoc = VariableDereferencePointer(Parser, DereferenceValue, &DerefVal, &Offset, &DerefType, &DerefIsLValue);
struct Value *ValueLoc = VariableAllocValueFromExistingData(Parser, DerefType, (union AnyValue *)DerefDataLoc, DerefIsLValue, DerefVal);
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
}
void ExpressionPushInt(struct ParseState *Parser, struct ExpressionStack **StackTop, int IntValue)
{
struct Value *ValueLoc = VariableAllocValueFromType(Parser, &IntType, FALSE, NULL, FALSE);
ValueLoc->Val->Integer = IntValue;
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
}
#ifndef NO_FP
void ExpressionPushFP(struct ParseState *Parser, struct ExpressionStack **StackTop, double FPValue)
{
struct Value *ValueLoc = VariableAllocValueFromType(Parser, &FPType, FALSE, NULL, FALSE);
ValueLoc->Val->FP = FPValue;
ExpressionStackPushValueNode(Parser, StackTop, ValueLoc);
}
#endif
/* assign to a pointer */
void ExpressionAssignToPointer(struct ParseState *Parser, struct Value *ToValue, struct Value *FromValue, const char *FuncName, int ParamNo, int AllowPointerCoercion)
{
struct ValueType *PointedToType = ToValue->Typ->FromType;
if (FromValue->Typ == ToValue->Typ || FromValue->Typ == VoidPtrType || (ToValue->Typ == VoidPtrType && FromValue->Typ->Base == TypePointer))
ToValue->Val->NativePointer = FromValue->Val->NativePointer; /* plain old pointer assignment */
else if (FromValue->Typ->Base == TypeArray && (PointedToType == FromValue->Typ->FromType || ToValue->Typ == VoidPtrType))
{
/* the form is: blah *x = array of blah */
ToValue->Val->NativePointer = (void *)&FromValue->Val->ArrayMem[0];
}
else if (FromValue->Typ->Base == TypePointer && FromValue->Typ->FromType->Base == TypeArray &&
(PointedToType == FromValue->Typ->FromType->FromType || ToValue->Typ == VoidPtrType) )
{
/* the form is: blah *x = pointer to array of blah */
ToValue->Val->NativePointer = VariableDereferencePointer(Parser, FromValue, NULL, NULL, NULL, NULL);
}
else if (IS_NUMERIC_COERCIBLE(FromValue) && ExpressionCoerceInteger(FromValue) == 0)
{
/* null pointer assignment */
ToValue->Val->NativePointer = NULL;
}
else if (AllowPointerCoercion && IS_NUMERIC_COERCIBLE(FromValue))
{
/* assign integer to native pointer */
ToValue->Val->NativePointer = (void *)ExpressionCoerceUnsignedInteger(FromValue);
}
else
AssignFail(Parser, "%t from %t", ToValue->Typ, FromValue->Typ, 0, 0, FuncName, ParamNo);
}
/* assign any kind of value */
void ExpressionAssign(struct ParseState *Parser, struct Value *DestValue, struct Value *SourceValue, int Force, const char *FuncName, int ParamNo, int AllowPointerCoercion)
{
if (!DestValue->IsLValue && !Force)
AssignFail(Parser, "not an lvalue", NULL, NULL, 0, 0, FuncName, ParamNo);
if (IS_NUMERIC_COERCIBLE(DestValue) && !IS_NUMERIC_COERCIBLE_PLUS_POINTERS(SourceValue, AllowPointerCoercion))
AssignFail(Parser, "%t from %t", DestValue->Typ, SourceValue->Typ, 0, 0, FuncName, ParamNo);
switch (DestValue->Typ->Base)
{
case TypeInt: DestValue->Val->Integer = ExpressionCoerceInteger(SourceValue); break;
case TypeShort: DestValue->Val->ShortInteger = ExpressionCoerceInteger(SourceValue); break;
case TypeChar: DestValue->Val->Character = ExpressionCoerceUnsignedInteger(SourceValue); break;
case TypeUnsignedInt: DestValue->Val->UnsignedInteger = ExpressionCoerceUnsignedInteger(SourceValue); break;
case TypeUnsignedShort: DestValue->Val->UnsignedShortInteger = ExpressionCoerceUnsignedInteger(SourceValue); break;
#ifndef NO_FP
case TypeFP:
if (!IS_NUMERIC_COERCIBLE_PLUS_POINTERS(SourceValue, AllowPointerCoercion))
AssignFail(Parser, "%t from %t", DestValue->Typ, SourceValue->Typ, 0, 0, FuncName, ParamNo);
DestValue->Val->FP = ExpressionCoerceFP(SourceValue);
break;
#endif
case TypePointer:
ExpressionAssignToPointer(Parser, DestValue, SourceValue, FuncName, ParamNo, AllowPointerCoercion);
break;
case TypeArray:
if (DestValue->Typ != SourceValue->Typ)
AssignFail(Parser, "%t from %t", DestValue->Typ, SourceValue->Typ, 0, 0, FuncName, ParamNo);
if (DestValue->Typ->ArraySize != SourceValue->Typ->ArraySize)
AssignFail(Parser, "from an array of size %d to one of size %d", NULL, NULL, DestValue->Typ->ArraySize, SourceValue->Typ->ArraySize, FuncName, ParamNo);
memcpy((void *)DestValue->Val, (void *)SourceValue->Val, TypeSizeValue(DestValue));
break;
case TypeStruct:
case TypeUnion:
if (DestValue->Typ != SourceValue->Typ)
AssignFail(Parser, "%t from %t", DestValue->Typ, SourceValue->Typ, 0, 0, FuncName, ParamNo);
memcpy((void *)DestValue->Val, (void *)SourceValue->Val, TypeSizeValue(SourceValue));
break;
default:
AssignFail(Parser, "%t", DestValue->Typ, NULL, 0, 0, FuncName, ParamNo);
break;
}
}
/* evaluate a prefix operator */
void ExpressionPrefixOperator(struct ParseState *Parser, struct ExpressionStack **StackTop, enum LexToken Op, struct Value *TopValue)
{
struct Value *Result;
if (Parser->Mode != RunModeRun)
{
/* we're not running it so just return 0 */
ExpressionPushInt(Parser, StackTop, 0);
return;
}
debugf("ExpressionPrefixOperator()\n");
switch (Op)
{
case TokenAmpersand:
if (!TopValue->IsLValue)
ProgramFail(Parser, "can't get the address of this");
Result = VariableAllocValueFromType(Parser, TypeGetMatching(Parser, TopValue->Typ, TypePointer, 0, StrEmpty), FALSE, NULL, FALSE);
Result->Val->NativePointer = TopValue->Val;
ExpressionStackPushValueNode(Parser, StackTop, Result);
break;
case TokenAsterisk:
ExpressionStackPushDereference(Parser, StackTop, TopValue);
break;
case TokenSizeof:
/* return the size of the argument */
if (TopValue->Typ == &TypeType)
ExpressionPushInt(Parser, StackTop, TypeSize(TopValue->Val->Typ, TopValue->Val->Typ->ArraySize, TRUE));
else
ExpressionPushInt(Parser, StackTop, TypeSize(TopValue->Typ, TopValue->Typ->ArraySize, TRUE));
break;
case TokenLeftSquareBracket:
/* XXX */
ProgramFail(Parser, "not supported");
break;
case TokenOpenBracket:
/* XXX - cast */
ProgramFail(Parser, "not supported");
break;
default:
/* an arithmetic operator */
#ifndef NO_FP
if (TopValue->Typ == &FPType)
{
/* floating point prefix arithmetic */
double ResultFP;
switch (Op)
{
case TokenPlus: ResultFP = TopValue->Val->FP; break;
case TokenMinus: ResultFP = -TopValue->Val->FP; break;
default: ProgramFail(Parser, "invalid operation"); break;
}
ExpressionPushFP(Parser, StackTop, ResultFP);
}
else
#endif
if (IS_NUMERIC_COERCIBLE(TopValue))
{
/* integer prefix arithmetic */
int ResultInt = 0;
int TopInt = ExpressionCoerceInteger(TopValue);
switch (Op)
{
case TokenPlus: ResultInt = TopInt; break;
case TokenMinus: ResultInt = -TopInt; break;
case TokenIncrement: ResultInt = ExpressionAssignInt(Parser, TopValue, TopInt+1, FALSE); break;
case TokenDecrement: ResultInt = ExpressionAssignInt(Parser, TopValue, TopInt-1, FALSE); break;
case TokenUnaryNot: ResultInt = !TopInt; break;
case TokenUnaryExor: ResultInt = ~TopInt; break;
default: ProgramFail(Parser, "invalid operation"); break;
}
ExpressionPushInt(Parser, StackTop, ResultInt);
}
else if (TopValue->Typ->Base == TypePointer)
{
/* pointer prefix arithmetic */
int Size = TypeSize(TopValue->Typ->FromType, 0, TRUE);
struct Value *StackValue;
if (TopValue->Val->NativePointer == NULL)
ProgramFail(Parser, "invalid use of a NULL pointer");
if (!TopValue->IsLValue)
ProgramFail(Parser, "can't assign to this");
switch (Op)
{
case TokenIncrement: TopValue->Val->NativePointer = (void *)((char *)TopValue->Val->NativePointer + Size); break;
case TokenDecrement: TopValue->Val->NativePointer = (void *)((char *)TopValue->Val->NativePointer - Size); break;
default: ProgramFail(Parser, "invalid operation"); break;
}
StackValue = ExpressionStackPushValueByType(Parser, StackTop, TopValue->Typ);
StackValue->Val->NativePointer = TopValue->Val->NativePointer;
}
else
ProgramFail(Parser, "invalid operation");
break;
}
}
/* evaluate a postfix operator */
void ExpressionPostfixOperator(struct ParseState *Parser, struct ExpressionStack **StackTop, enum LexToken Op, struct Value *TopValue)
{
if (Parser->Mode != RunModeRun)
{
/* we're not running it so just return 0 */
ExpressionPushInt(Parser, StackTop, 0);
return;
}
debugf("ExpressionPostfixOperator()\n");
if (IS_NUMERIC_COERCIBLE(TopValue))
{
int ResultInt = 0;
int TopInt = ExpressionCoerceInteger(TopValue);
switch (Op)
{
case TokenIncrement: ResultInt = ExpressionAssignInt(Parser, TopValue, TopInt+1, TRUE); break;
case TokenDecrement: ResultInt = ExpressionAssignInt(Parser, TopValue, TopInt-1, TRUE); break;
case TokenRightSquareBracket: ProgramFail(Parser, "not supported"); break; /* XXX */
case TokenCloseBracket: ProgramFail(Parser, "not supported"); break; /* XXX */
default: ProgramFail(Parser, "invalid operation"); break;
}
ExpressionPushInt(Parser, StackTop, ResultInt);
}
else if (TopValue->Typ->Base == TypePointer)
{
/* pointer postfix arithmetic */
int Size = TypeSize(TopValue->Typ->FromType, 0, TRUE);
struct Value *StackValue;
void *OrigPointer = TopValue->Val->NativePointer;
if (TopValue->Val->NativePointer == NULL)
ProgramFail(Parser, "invalid use of a NULL pointer");
if (!TopValue->IsLValue)
ProgramFail(Parser, "can't assign to this");
switch (Op)
{
case TokenIncrement: TopValue->Val->NativePointer = (void *)((char *)TopValue->Val->NativePointer + Size); break;
case TokenDecrement: TopValue->Val->NativePointer = (void *)((char *)TopValue->Val->NativePointer - Size); break;
default: ProgramFail(Parser, "invalid operation"); break;
}
StackValue = ExpressionStackPushValueByType(Parser, StackTop, TopValue->Typ);
StackValue->Val->NativePointer = OrigPointer;
}
else
ProgramFail(Parser, "invalid operation");
}
/* evaluate an infix operator */
void ExpressionInfixOperator(struct ParseState *Parser, struct ExpressionStack **StackTop, enum LexToken Op, struct Value *BottomValue, struct Value *TopValue)
{
int ResultInt = 0;
struct Value *StackValue;
void *NativePointer;
if (Parser->Mode != RunModeRun)
{
/* we're not running it so just return 0 */
ExpressionPushInt(Parser, StackTop, 0);
return;
}
debugf("ExpressionInfixOperator()\n");
if (Op == TokenLeftSquareBracket)
{
/* array index */
int ArrayIndex;
struct Value *Result;
if (!IS_NUMERIC_COERCIBLE(TopValue))
ProgramFail(Parser, "array index must be an integer");
ArrayIndex = ExpressionCoerceInteger(TopValue);
/* make the array element result */
switch (BottomValue->Typ->Base)
{
case TypeArray: Result = VariableAllocValueFromExistingData(Parser, BottomValue->Typ->FromType, (union AnyValue *)(&BottomValue->Val->ArrayMem[0] + TypeSize(BottomValue->Typ->FromType, 0, TRUE) * ArrayIndex), BottomValue->IsLValue, BottomValue->LValueFrom); break;
case TypePointer: Result = VariableAllocValueFromExistingData(Parser, BottomValue->Typ->FromType, (union AnyValue *)((char *)BottomValue->Val->NativePointer + TypeSize(BottomValue->Typ->FromType, 0, TRUE) * ArrayIndex), BottomValue->IsLValue, BottomValue->LValueFrom); break;
default: ProgramFail(Parser, "this %t is not an array", BottomValue->Typ);
}
ExpressionStackPushValueNode(Parser, StackTop, Result);
}
#ifndef NO_FP
else if ( (TopValue->Typ == &FPType && BottomValue->Typ == &FPType) ||
(TopValue->Typ == &FPType && IS_NUMERIC_COERCIBLE(BottomValue)) ||
(IS_NUMERIC_COERCIBLE(TopValue) && BottomValue->Typ == &FPType) )
{
/* floating point infix arithmetic */
int ResultIsInt = FALSE;
double ResultFP = 0.0;
double TopFP = (TopValue->Typ == &FPType) ? TopValue->Val->FP : (double)ExpressionCoerceInteger(TopValue);
double BottomFP = (BottomValue->Typ == &FPType) ? BottomValue->Val->FP : (double)ExpressionCoerceInteger(BottomValue);
switch (Op)
{
case TokenAssign: ResultFP = ExpressionAssignFP(Parser, BottomValue, TopFP); break;
case TokenAddAssign: ResultFP = ExpressionAssignFP(Parser, BottomValue, BottomFP + TopFP); break;
case TokenSubtractAssign: ResultFP = ExpressionAssignFP(Parser, BottomValue, BottomFP - TopFP); break;
case TokenMultiplyAssign: ResultFP = ExpressionAssignFP(Parser, BottomValue, BottomFP * TopFP); break;
case TokenDivideAssign: ResultFP = ExpressionAssignFP(Parser, BottomValue, BottomFP / TopFP); break;
case TokenEqual: ResultInt = BottomFP == TopFP; ResultIsInt = TRUE; break;
case TokenNotEqual: ResultInt = BottomFP != TopFP; ResultIsInt = TRUE; break;
case TokenLessThan: ResultInt = BottomFP < TopFP; ResultIsInt = TRUE; break;
case TokenGreaterThan: ResultInt = BottomFP > TopFP; ResultIsInt = TRUE; break;
case TokenLessEqual: ResultInt = BottomFP <= TopFP; ResultIsInt = TRUE; break;
case TokenGreaterEqual: ResultInt = BottomFP >= TopFP; ResultIsInt = TRUE; break;
case TokenPlus: ResultFP = BottomFP + TopFP; break;
case TokenMinus: ResultFP = BottomFP - TopFP; break;
case TokenAsterisk: ResultFP = BottomFP * TopFP; break;
case TokenSlash: ResultFP = BottomFP / TopFP; break;
default: ProgramFail(Parser, "invalid operation"); break;
}
if (ResultIsInt)
ExpressionPushInt(Parser, StackTop, ResultInt);
else
ExpressionPushFP(Parser, StackTop, ResultFP);
}
#endif
else if (IS_NUMERIC_COERCIBLE(TopValue) && IS_NUMERIC_COERCIBLE(BottomValue))
{
/* integer operation */
int TopInt = ExpressionCoerceInteger(TopValue);
int BottomInt = ExpressionCoerceInteger(BottomValue);
switch (Op)
{
case TokenAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, TopInt, FALSE); break;
case TokenAddAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt + TopInt, FALSE); break;
case TokenSubtractAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt - TopInt, FALSE); break;
case TokenMultiplyAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt * TopInt, FALSE); break;
case TokenDivideAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt / TopInt, FALSE); break;
#ifndef NO_MODULUS
case TokenModulusAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt % TopInt, FALSE); break;
#endif
case TokenShiftLeftAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt << TopInt, FALSE); break;
case TokenShiftRightAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt >> TopInt, FALSE); break;
case TokenArithmeticAndAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt & TopInt, FALSE); break;
case TokenArithmeticOrAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt | TopInt, FALSE); break;
case TokenArithmeticExorAssign: ResultInt = ExpressionAssignInt(Parser, BottomValue, BottomInt ^ TopInt, FALSE); break;
case TokenQuestionMark: ProgramFail(Parser, "not supported"); break; /* XXX */
case TokenColon: ProgramFail(Parser, "not supported"); break; /* XXX */
case TokenLogicalOr: ResultInt = BottomInt || TopInt; break;
case TokenLogicalAnd: ResultInt = BottomInt && TopInt; break;
case TokenArithmeticOr: ResultInt = BottomInt | TopInt; break;
case TokenArithmeticExor: ResultInt = BottomInt ^ TopInt; break;
case TokenAmpersand: ResultInt = BottomInt & TopInt; break;
case TokenEqual: ResultInt = BottomInt == TopInt; break;
case TokenNotEqual: ResultInt = BottomInt != TopInt; break;
case TokenLessThan: ResultInt = BottomInt < TopInt; break;
case TokenGreaterThan: ResultInt = BottomInt > TopInt; break;
case TokenLessEqual: ResultInt = BottomInt <= TopInt; break;
case TokenGreaterEqual: ResultInt = BottomInt >= TopInt; break;
case TokenShiftLeft: ResultInt = BottomInt << TopInt; break;
case TokenShiftRight: ResultInt = BottomInt << TopInt; break;
case TokenPlus: ResultInt = BottomInt + TopInt; break;
case TokenMinus: ResultInt = BottomInt - TopInt; break;
case TokenAsterisk: ResultInt = BottomInt * TopInt; break;
case TokenSlash: ResultInt = BottomInt / TopInt; break;
#ifndef NO_MODULUS
case TokenModulus: ResultInt = BottomInt % TopInt; break;
#endif
default: ProgramFail(Parser, "invalid operation"); break;
}
ExpressionPushInt(Parser, StackTop, ResultInt);
}
else if (BottomValue->Typ->Base == TypePointer && IS_NUMERIC_COERCIBLE(TopValue))
{
/* pointer/integer infix arithmetic */
int TopInt = ExpressionCoerceInteger(TopValue);
if (Op == TokenEqual || Op == TokenNotEqual)
{
/* comparison to a NULL pointer */
if (TopInt != 0)
ProgramFail(Parser, "invalid operation");
if (Op == TokenEqual)
ExpressionPushInt(Parser, StackTop, BottomValue->Val->NativePointer == NULL);
else
ExpressionPushInt(Parser, StackTop, BottomValue->Val->NativePointer != NULL);
}
else if (Op == TokenPlus || Op == TokenMinus)
{
/* pointer arithmetic */
int Size = TypeSize(BottomValue->Typ->FromType, 0, TRUE);
NativePointer = BottomValue->Val->NativePointer;
if (NativePointer == NULL)
ProgramFail(Parser, "invalid use of a NULL pointer");
if (Op == TokenPlus)
NativePointer = (void *)((char *)NativePointer + TopInt * Size);
else
NativePointer = (void *)((char *)NativePointer - TopInt * Size);
StackValue = ExpressionStackPushValueByType(Parser, StackTop, BottomValue->Typ);
StackValue->Val->NativePointer = NativePointer;
}
else if (Op == TokenAssign && TopInt == 0)
{
/* assign a NULL pointer */
HeapUnpopStack(sizeof(struct Value)); /* XXX - possible bug if lvalue is a temp value and takes more than sizeof(struct Value) */
ExpressionAssign(Parser, BottomValue, TopValue, FALSE, NULL, 0, FALSE);
ExpressionStackPushValueNode(Parser, StackTop, BottomValue);
}
else
ProgramFail(Parser, "invalid operation");
}
else if (BottomValue->Typ->Base == TypePointer && TopValue->Typ->Base == TypePointer && Op != TokenAssign)
{
/* pointer/pointer operations */
char *TopLoc = (char *)TopValue->Val->NativePointer;
char *BottomLoc = (char *)BottomValue->Val->NativePointer;
switch (Op)
{
case TokenEqual: ExpressionPushInt(Parser, StackTop, BottomLoc == TopLoc); break;
case TokenNotEqual: ExpressionPushInt(Parser, StackTop, BottomLoc != TopLoc); break;
case TokenMinus: ExpressionPushInt(Parser, StackTop, BottomLoc - TopLoc); break;
default: ProgramFail(Parser, "invalid operation"); break;
}
}
else if (Op == TokenAssign)
{
/* assign a non-numeric type */
HeapUnpopStack(sizeof(struct Value)); /* XXX - possible bug if lvalue is a temp value and takes more than sizeof(struct Value) */
ExpressionAssign(Parser, BottomValue, TopValue, FALSE, NULL, 0, FALSE);
ExpressionStackPushValueNode(Parser, StackTop, BottomValue);
}
else if (Op == TokenCast)
{
/* cast a value to a different type */ /* XXX - possible bug if the destination type takes more than sizeof(struct Value) + sizeof(struct ValueType *) */
struct Value *ValueLoc = ExpressionStackPushValueByType(Parser, StackTop, BottomValue->Val->Typ);
ExpressionAssign(Parser, ValueLoc, TopValue, TRUE, NULL, 0, TRUE);
}
else
ProgramFail(Parser, "invalid operation");
}
/* take the contents of the expression stack and compute the top until there's nothing greater than the given precedence */
void ExpressionStackCollapse(struct ParseState *Parser, struct ExpressionStack **StackTop, int Precedence)
{
int FoundPrecedence = Precedence;
struct Value *TopValue;
struct Value *BottomValue;
struct ExpressionStack *TopStackNode = *StackTop;
struct ExpressionStack *TopOperatorNode;
debugf("ExpressionStackCollapse(%d):\n", Precedence);
#ifdef DEBUG_EXPRESSIONS
ExpressionStackShow(*StackTop);
#endif
while (TopStackNode != NULL && TopStackNode->Next != NULL && FoundPrecedence >= Precedence)
{
/* find the top operator on the stack */
if (TopStackNode->Order == OrderNone)
TopOperatorNode = TopStackNode->Next;
else
TopOperatorNode = TopStackNode;
FoundPrecedence = TopOperatorNode->Precedence;
/* does it have a high enough precedence? */
if (FoundPrecedence >= Precedence && TopOperatorNode != NULL)
{
/* execute this operator */
switch (TopOperatorNode->Order)
{
case OrderPrefix:
/* prefix evaluation */
debugf("prefix evaluation\n");
TopValue = TopStackNode->Val;
/* pop the value and then the prefix operator - assume they'll still be there until we're done */
HeapPopStack(TopOperatorNode, sizeof(struct ExpressionStack)*2 + sizeof(struct Value) + TypeStackSizeValue(TopValue));
*StackTop = TopOperatorNode->Next;
/* do the prefix operation */
ExpressionPrefixOperator(Parser, StackTop, TopOperatorNode->Op, TopValue);
break;
case OrderPostfix:
/* postfix evaluation */
debugf("postfix evaluation\n");
TopValue = TopStackNode->Next->Val;
/* pop the postfix operator and then the value - assume they'll still be there until we're done */
HeapPopStack(TopValue, sizeof(struct ExpressionStack)*2 + sizeof(struct Value) + TypeStackSizeValue(TopValue));
*StackTop = TopStackNode->Next->Next;
/* do the postfix operation */
ExpressionPostfixOperator(Parser, StackTop, TopOperatorNode->Op, TopValue);
break;
case OrderInfix:
/* infix evaluation */
debugf("infix evaluation\n");
TopValue = TopStackNode->Val;
BottomValue = TopOperatorNode->Next->Val;
/* pop a value, the operator and another value - assume they'll still be there until we're done */
HeapPopStack(BottomValue, sizeof(struct ExpressionStack)*3 + sizeof(struct Value)*2 + TypeStackSizeValue(TopValue) + TypeStackSizeValue(BottomValue));
*StackTop = TopOperatorNode->Next->Next;
/* do the infix operation */
ExpressionInfixOperator(Parser, StackTop, TopOperatorNode->Op, BottomValue, TopValue);
break;
case OrderNone:
/* this should never happen */
assert(TopOperatorNode->Order != OrderNone);
break;
}
}
#ifdef DEBUG_EXPRESSIONS
ExpressionStackShow(*StackTop);
#endif
TopStackNode = *StackTop;
}
debugf("ExpressionStackCollapse() finished\n");
#ifdef DEBUG_EXPRESSIONS
ExpressionStackShow(*StackTop);
#endif
}
/* push an operator on to the expression stack */
void ExpressionStackPushOperator(struct ParseState *Parser, struct ExpressionStack **StackTop, enum OperatorOrder Order, enum LexToken Token, int Precedence)
{
struct ExpressionStack *StackNode = VariableAlloc(Parser, sizeof(struct ExpressionStack), FALSE);
StackNode->Next = *StackTop;
StackNode->Order = Order;
StackNode->Op = Token;
StackNode->Precedence = Precedence;
*StackTop = StackNode;
debugf("ExpressionStackPushOperator()\n");
#ifdef FANCY_ERROR_MESSAGES
StackNode->Line = Parser->Line;
StackNode->CharacterPos = Parser->CharacterPos;
#endif
#ifdef DEBUG_EXPRESSIONS
ExpressionStackShow(*StackTop);
#endif
}
/* do the '.' and '->' operators */
void ExpressionGetStructElement(struct ParseState *Parser, struct ExpressionStack **StackTop, enum LexToken Token)
{
struct Value *Ident;
/* get the identifier following the '.' or '->' */
if (LexGetToken(Parser, &Ident, TRUE) != TokenIdentifier)
ProgramFail(Parser, "need an structure or union member after '%s'", (Token == TokenDot) ? "." : "->");
if (Parser->Mode == RunModeRun)
{
/* look up the struct element */
struct Value *ParamVal = (*StackTop)->Val;
struct Value *StructVal = ParamVal;
struct ValueType *StructType = ParamVal->Typ;
char *DerefDataLoc = (char *)ParamVal->Val;
struct Value *MemberValue;
struct Value *Result;
/* if we're doing '->' dereference the struct pointer first */
if (Token == TokenArrow)
DerefDataLoc = VariableDereferencePointer(Parser, ParamVal, &StructVal, NULL, &StructType, NULL);
if (StructType->Base != TypeStruct && StructType->Base != TypeUnion)
ProgramFail(Parser, "can't use '%s' on something that's not a struct or union %s : it's a %t", (Token == TokenDot) ? "." : "->", (Token == TokenArrow) ? "pointer" : "", ParamVal->Typ);
if (!TableGet(StructType->Members, Ident->Val->Identifier, &MemberValue))
ProgramFail(Parser, "doesn't have a member called '%s'", Ident->Val->Identifier);
/* pop the value - assume it'll still be there until we're done */
HeapPopStack(ParamVal, sizeof(struct ExpressionStack) + sizeof(struct Value) + TypeStackSizeValue(StructVal));
*StackTop = (*StackTop)->Next;
/* make the result value for this member only */
Result = VariableAllocValueFromExistingData(Parser, MemberValue->Typ, (void *)(DerefDataLoc + MemberValue->Val->Integer), TRUE, (StructVal != NULL) ? StructVal->LValueFrom : NULL);
ExpressionStackPushValueNode(Parser, StackTop, Result);
}
}
/* parse an expression with operator precedence */
int ExpressionParse(struct ParseState *Parser, struct Value **Result)
{
struct Value *LexValue;
int PrefixState = TRUE;
int Done = FALSE;
int BracketPrecedence = 0;
int LocalPrecedence;
int Precedence = 0;
struct ExpressionStack *StackTop = NULL;
int TernaryDepth = 0;
debugf("ExpressionParse():\n");
do
{
struct ParseState PreState = *Parser;
enum LexToken Token = LexGetToken(Parser, &LexValue, TRUE);
if ( ( ( (int)Token > TokenComma && (int)Token <= (int)TokenOpenBracket) ||
(Token == TokenCloseBracket && BracketPrecedence != 0)) &&
(Token != TokenColon || TernaryDepth != 0) )
{
/* it's an operator with precedence */
if (PrefixState)
{
/* expect a prefix operator */
if (OperatorPrecedence[(int)Token].PrefixPrecedence == 0)
ProgramFail(Parser, "operator not expected here");
LocalPrecedence = OperatorPrecedence[(int)Token].PrefixPrecedence;
Precedence = BracketPrecedence + LocalPrecedence;
if (Token == TokenOpenBracket)
{
/* it's either a new bracket level or a cast */
enum LexToken BracketToken = LexGetToken(Parser, &LexValue, FALSE);
if (IS_TYPE_TOKEN(BracketToken))
{
/* it's a cast - get the new type */
struct ValueType *CastType;
char *CastIdentifier;
struct Value *CastTypeValue;
TypeParse(Parser, &CastType, &CastIdentifier);
if (LexGetToken(Parser, &LexValue, TRUE) != TokenCloseBracket)
ProgramFail(Parser, "brackets not closed");
/* scan and collapse the stack to the precedence of this infix cast operator, then push */
Precedence = BracketPrecedence + OperatorPrecedence[(int)TokenCast].PrefixPrecedence;
ExpressionStackCollapse(Parser, &StackTop, Precedence);
CastTypeValue = VariableAllocValueFromType(Parser, &TypeType, FALSE, NULL, FALSE);
CastTypeValue->Val->Typ = CastType;
ExpressionStackPushValueNode(Parser, &StackTop, CastTypeValue);
ExpressionStackPushOperator(Parser, &StackTop, OrderInfix, TokenCast, Precedence);
}
else
{
/* boost the bracket operator precedence */
BracketPrecedence += BRACKET_PRECEDENCE;
}
}
else
{
/* scan and collapse the stack to the precedence of this operator, then push */
ExpressionStackCollapse(Parser, &StackTop, Precedence);
ExpressionStackPushOperator(Parser, &StackTop, OrderPrefix, Token, Precedence);
}
}
else
{
/* expect an infix or postfix operator */
if (OperatorPrecedence[(int)Token].PostfixPrecedence != 0)
{
switch (Token)
{
case TokenCloseBracket:
case TokenRightSquareBracket:
if (BracketPrecedence == 0)
{
/* assume this bracket is after the end of the expression */
*Parser = PreState;
Done = TRUE;
}
else
BracketPrecedence -= BRACKET_PRECEDENCE;
break;
default:
/* scan and collapse the stack to the precedence of this operator, then push */
Precedence = BracketPrecedence + OperatorPrecedence[(int)Token].PostfixPrecedence;
ExpressionStackCollapse(Parser, &StackTop, Precedence);
ExpressionStackPushOperator(Parser, &StackTop, OrderPostfix, Token, Precedence);
break;
}
}
else if (OperatorPrecedence[(int)Token].InfixPrecedence != 0)
{
/* scan and collapse the stack, then push */
if (Token == TokenDot || Token == TokenArrow)
ExpressionGetStructElement(Parser, &StackTop, Token); /* this operator is followed by a struct element so handle it as a special case */
else
{
/* a standard infix operator */
Precedence = BracketPrecedence + OperatorPrecedence[(int)Token].InfixPrecedence;
/* for right to left order, only go down to the next higher precedence so we evaluate it in reverse order */
/* for left to right order, collapse down to this precedence so we evaluate it in forward order */
if (IS_LEFT_TO_RIGHT(OperatorPrecedence[(int)Token].InfixPrecedence))
ExpressionStackCollapse(Parser, &StackTop, Precedence);
else
ExpressionStackCollapse(Parser, &StackTop, Precedence+1);
ExpressionStackPushOperator(Parser, &StackTop, OrderInfix, Token, Precedence);
PrefixState = TRUE;
}
/* treat an open square bracket as an infix array index operator followed by an open bracket */
if (Token == TokenLeftSquareBracket)
{
/* boost the bracket operator precedence, then push */
BracketPrecedence += BRACKET_PRECEDENCE;
}
}
else
ProgramFail(Parser, "operator not expected here");
}
}
else if (Token == TokenIdentifier)
{
/* it's a variable, function or a macro */
if (!PrefixState)