ORCA-C/Expression.pas

3761 lines
135 KiB
ObjectPascal

{$optimize 1}
{---------------------------------------------------------------}
{ }
{ Expression }
{ }
{ Evaluate expressions }
{ }
{ Note: The expression evaluator uses the scanner to fetch }
{ tokens, but IT IS ALSO USED BY THE SCANNER to evaluate }
{ expressions in preprocessor commands. This circular }
{ dependency is handle by defining all of the expression }
{ evaluator's external types, constants, and variables in the }
{ CCOMMON module. The only procedure from this module used by }
{ the scanner is Expression, which is declared as an external }
{ procedure in the scanner. }
{ }
{ External Variables: }
{ }
{ startExpression - tokens that may start an expression }
{ bitDisp,bitSize - bit field disp, size }
{ unsigned - is the bit field unsigned? }
{ isBitField - is the field a bit field? }
{ }
{ External Subroutines: }
{ }
{ AssignmentConversion - do type checking and conversions for }
{ assignment statements }
{ CompareToZero - Compare the result on tos to zero. }
{ DisposeTree - dispose of an expression tree }
{ DoSelection - Find the displacement & type for a }
{ selection operation }
{ Expression - handle an expression }
{ FreeTemp - place a temporary label in the available label }
{ list }
{ GenerateCode - generate code from a fully formed expression }
{ tree }
{ GetTemp - find a temporary work variable }
{ InitExpression - initlialize the expression handler }
{ UsualBinaryConversions - performs the usual binary }
{ conversions }
{ UsualUnaryConversions - performs the usual unary conversions }
{ }
{---------------------------------------------------------------}
unit Expression;
{$LibPrefix '0/obj/'}
interface
uses CCommon, Table, CGI, Scanner, Symbol, MM;
{$segment 'exp'}
var
startExpression: tokenSet; {tokens that can start an expression}
{set by DoSelection}
{------------------}
bitDisp,bitSize: integer; {bit field disp, size}
unsigned: boolean; {is the bit field unsigned?}
isBitField: boolean; {is the field a bit field?}
{misc}
{----}
lastwasconst: boolean; {did the last GenerateCode result in an integer constant?}
lastconst: longint; {last integer constant from GenerateCode}
{---------------------------------------------------------------}
procedure AssignmentConversion (t1, t2: typePtr; isConstant: boolean;
value: longint; genCode, checkConst: boolean);
{ TOS is of type t2, and is about to be stored to a variable of }
{ type t1 by an assignment or a return statement. Make sure }
{ this is legal, and do any necessary type conversions on t2, }
{ which is on the top of the evaluation stack. Flag an error }
{ if the conversion is illegal. }
{ }
{ parameters: }
{ t1 - type of the variable }
{ t2 - type of the expression }
{ isConstant - is the rhs a constant? }
{ value - if isConstant = true, then this is the value }
{ genCode - should conversion code be generated? }
{ checkConst - check for assignments to constants? }
procedure CompareToZero(op: pcodes);
{ Compare the result on tos to zero. }
{ }
{ This procedure is used by the logical statements to compare }
{ _any_ scalar result to zero, giving a boolean result. }
{ }
{ parameters: }
{ op - operation to use on the compare }
procedure DisposeTree (tree: tokenPtr);
{ dispose of an expression tree }
{ }
{ parameters: }
{ tree - head of the expression tree to dispose of }
procedure DoSelection (lType: typePtr; tree: tokenPtr; var size: longint);
{ Find the displacement & type for a selection operation }
{ }
{ parameters: }
{ lType - structure/union type }
{ id - tag field name }
{ size - disp into the structure/union }
{ }
{ returned in non-local variables: }
{ bitDisp - displacement to bit field }
{ bitSize - size of bit field }
{ unsigned - is the bit field unsigned? }
{ isBitField - is the field a bit field? }
{ }
{ varaibles: }
{ expressionType - set to the type of the field }
procedure Expression (kind: expressionKind; stopSym: tokenSet);
{ handle an expression }
{ }
{ parameters: }
{ kind - Kind of expression; determines what operations }
{ and what kind of operands are allowed. }
{ stopSym - Set of symbols that can mark the end of an }
{ expression; used to skip tokens after syntax }
{ errors and to block certain operations. For }
{ example, the comma operator is not allowed in }
{ an expression when evaluating a function }
{ parameter list. }
{ }
{ variables: }
{ realExpressionValue - value of a real constant }
{ expression }
{ expressionValue - value of a constant expression }
{ expressionType - type of the constant expression }
procedure FreeTemp(labelNum, size: integer);
{ place a temporary label in the available label list }
{ }
{ parameters: }
{ labelNum - number of the label to free }
{ size - size of the variable }
{ }
{ variables: }
{ tempList - list of free labels }
procedure GenerateCode (tree: tokenPtr);
{ generate code from a fully formed expression tree }
{ }
{ parameters: }
{ tree - top of the expression tree to generate code from }
{ }
{ variables: }
{ expressionType - result type of the expression }
function GetTemp(size: integer): integer;
{ find a temporary work variable }
{ }
{ parameters: }
{ size - size of the variable }
{ }
{ variables: }
{ tempList - list of free labels }
{ }
{ Returns the label number. }
procedure InitExpression;
{ initialize the expression handler }
function UsualBinaryConversions (lType: typePtr): baseTypeEnum;
{ performs the usual binary conversions }
{ }
{ inputs: }
{ lType - type of the left operand }
{ expressionType - type of the right operand }
{ }
{ result: }
{ The base type of the operation to perform is }
{ returned. Any conversion code necessary has been }
{ generated. }
{ }
{ outputs: }
{ expressionType - set to result type }
function UsualUnaryConversions: baseTypeEnum;
{ performs the usual unary conversions }
{ }
{ inputs: }
{ expressionType - type of the operand }
{ }
{ result: }
{ The base type of the operation to perform is returned. }
{ Any conversion code necessary has been generated. }
{ }
{ outputs: }
{ expressionType - set to result type }
{---------------------------------------------------------------}
implementation
const
{notAnOperation is also used in TABLE.ASM}
notAnOperation = 200; {used as the icp for non-operation tokens}
var
{structured constants}
{--------------------}
startTerm: tokenSet; {tokens that can start a term}
{misc}
{----}
errorFound: boolean; {was there are error during generation?}
{-- Procedures imported from the parser ------------------------}
procedure Match (kind: tokenEnum; err: integer); extern;
{ insure that the next token is of the specified type }
{ }
{ parameters: }
{ kind - expected token kind }
{ err - error number if the expected token is not found }
procedure TypeSpecifier (doingFieldList,isConstant: boolean); extern;
{ handle a type specifier }
{ }
{ parameters: }
{ doingFieldList - are we processing a field list? }
{ isConstant - did we already find a constsy? }
{-- External unsigned math routines ----------------------------}
function lshr (x,y: longint): longint; extern;
function udiv (x,y: longint): longint; extern;
function uge (x,y: longint): longint; extern;
function ugt (x,y: longint): longint; extern;
function ule (x,y: longint): longint; extern;
function ult (x,y: longint): longint; extern;
function umod (x,y: longint): longint; extern;
function umul (x,y: longint): longint; extern;
{---------------------------------------------------------------}
function Unary(tp: baseTypeEnum): baseTypeEnum;
{ usual unary conversions }
{ }
{ This function returns the base type actually loaded on the }
{ stack for a particular data type. This corresponds to C's }
{ usual unary conversions. }
{ }
{ parameter: }
{ tp - data type }
{ }
{ result: }
{ Stack type. }
begin {Unary}
if tp in [cgByte,cgUByte,cgReal,cgDouble,cgComp] then
if tp in [cgByte,cgUByte] then
tp := cgWord
else {if tp in [cgReal,cgDouble,cgComp] then}
tp := cgExtended;
Unary := tp;
end; {Unary}
function UsualBinaryConversions {lType: typePtr): baseTypeEnum};
{ performs the usual binary conversions }
{ }
{ inputs: }
{ lType - type of the left operand }
{ expressionType - type of the right operand }
{ }
{ result: }
{ The base type of the operation to perform is }
{ returned. Any conversion code necessary has been }
{ generated. }
{ }
{ outputs: }
{ expressionType - set to result type }
var
rType: typePtr; {right type}
lt,rt: baseTypeEnum; {work variables}
begin {UsualBinaryConversions}
UsualBinaryConversions := cgULong;
if lType^.kind = pointerType then
lType := uLongPtr
else if lType^.kind = scalarType then
if lType^.baseType = cgVoid then begin
lType := uLongPtr;
Error(66);
end; {if}
rType := expressionType;
if rType^.kind = pointerType then
rType := uLongPtr
else if rType^.kind = scalarType then
if rType^.baseType = cgVoid then begin
rType := uLongPtr;
Error(66);
end; {if}
if (lType^.kind = scalarType) and (rType^.kind = scalarType) then begin
lt := Unary(lType^.baseType);
rt := Unary(rType^.baseType);
if lt <> rt then begin
if lt = cgExtended then begin
if rt in [cgWord,cgUWord,cgLong,cgULong] then
Gen2(pc_cnv, ord(rt), ord(cgExtended));
UsualBinaryConversions := cgExtended;
expressionType := extendedPtr;
end {if}
else if rt = cgExtended then begin
if lt in [cgWord,cgUWord,cgLong,cgULong] then
Gen2(pc_cnn, ord(lt), ord(cgExtended));
UsualBinaryConversions := cgExtended;
expressionType := extendedPtr;
end {else if}
else if lt = cgULong then begin
if rt in [cgWord,cgUWord] then
Gen2(pc_cnv, ord(rt), ord(cgULong));
UsualBinaryConversions := cgULong;
expressionType := uLongPtr;
end {else if}
else if rt = cgULong then begin
if lt in [cgWord,cgUWord] then
Gen2(pc_cnn, ord(lt), ord(cgULong));
UsualBinaryConversions := cgULong;
expressionType := uLongPtr;
end {else if}
else if lt = cgLong then begin
if rt in [cgWord,cgUWord] then
Gen2(pc_cnv, ord(rt), ord(cgLong));
UsualBinaryConversions := cgLong;
expressionType := longPtr;
end {else if}
else if rt = cgLong then begin
if lt in [cgWord,cgUWord] then
Gen2(pc_cnn, ord(lt), ord(cgLong));
UsualBinaryConversions := cgLong;
expressionType := longPtr;
end {else if}
else {one operand is unsigned in and the other is int} begin
UsualBinaryConversions := cgUWord;
expressionType := uWordPtr;
end; {else}
end {if}
else {types are the same}
UsualBinaryConversions := lt;
end {if}
else
Error(66);
end; {UsualBinaryConversions}
function UsualUnaryConversions{: baseTypeEnum};
{ performs the usual unary conversions }
{ }
{ inputs: }
{ expressionType - type of the operand }
{ }
{ result: }
{ The base type of the operation to perform is returned. }
{ Any conversion code necessary has been generated. }
{ }
{ outputs: }
{ expressionType - set to result type }
var
lt,rt: baseTypeEnum; {work variables}
begin {UsualUnaryConversions}
UsualUnaryConversions := cgULong;
if expressionType^.kind = scalarType then
UsualUnaryConversions := Unary(expressionType^.baseType)
{else if expressionType^.kind in [arrayType,pointerType] then
UsualUnaryConversions := cgULong};
end; {UsualUnaryConversions}
procedure DisposeTree {tree: tokenPtr};
{ dispose of an expression tree }
{ }
{ parameters: }
{ tree - head of the expression tree to dispose of }
begin {DisposeTree}
if tree <> nil then begin
DisposeTree(tree^.left);
DisposeTree(tree^.middle);
DisposeTree(tree^.right);
dispose(tree);
end; {if}
end; {DisposeTree}
procedure AssignmentConversion {t1, t2: typePtr; isConstant: boolean;
value: longint; genCode, checkConst: boolean};
{ TOS is of type t2, and is about to be stored to a variable of }
{ type t1 by an assignment or a return statement. Make sure }
{ this is legal, and do any necessary type conversions on t2, }
{ which is on the top of the evaluation stack. Flag an error }
{ if the conversion is illegal. }
{ }
{ parameters: }
{ t1 - type of the variable }
{ t2 - type of the expression }
{ isConstant - is the rhs a constant? }
{ value - if isConstant = true, then this is the value }
{ genCode - should conversion code be generated? }
{ checkConst - check for assignments to constants? }
var
baseType1,baseType2: baseTypeEnum; {temp variables (for speed)}
kind1,kind2: typeKind; {temp variables (for speed)}
begin {AssignmentConversion}
kind1 := t1^.kind;
kind2 := t2^.kind;
if t1^.isConstant then
if genCode then
if checkConst then
Error(93);
if kind2 = definedType then
AssignmentConversion(t1, t2^.dType, false, 0, genCode, checkConst)
else if kind1 = definedType then
AssignmentConversion(t1^.dType, t2, false, 0, genCode, checkConst)
else if kind2 in
[scalarType,pointerType,enumType,structType,unionType,arrayType,functionType] then
case kind1 of
scalarType: begin
baseType1 := t1^.baseType;
if baseType1 = cgString then
Error(64)
else if baseType1 = cgVoid then
Error(65)
else if kind2 = enumType then begin
if genCode then
Gen2(pc_cnv, ord(cgWord), ord(baseType1));
end {else if}
else if kind2 = scalarType then begin
baseType2 := t2^.baseType;
if baseType2 in [cgString,cgVoid] then
Error(47)
else if genCode then
Gen2(pc_cnv, ord(baseType2), ord(baseType1));
end {else if}
else
Error(47);
end;
arrayType: ;
{any errors are handled elsewhere}
functionType,enumConst:
Error(47);
pointerType: begin
if kind2 = pointerType then begin
if not CompTypes(t1, t2) then
Error(47);
end {if}
else if kind2 = arrayType then begin
if not CompTypes(t1^.ptype, t2^.atype) then
if t1^.ptype^.baseType <> cgVoid then
Error(47);
end {if}
else if kind2 = scalarType then begin
if isConstant and (value = 0) then begin
if genCode then
Gen2(pc_cnv, ord(t2^.baseType), ord(cgULong));
end {if}
else
Error(47);
end {else if}
else
Error(47);
end;
enumType: begin
if kind2 = scalarType then begin
baseType2 := t2^.baseType;
if baseType2 in [cgString,cgVoid] then
Error(47)
else if genCode then
Gen2(pc_cnv, ord(baseType2), ord(cgWord));
end {if}
else if kind2 <> enumType then
Error(47);
end;
definedType:
AssignmentConversion(t1^.dType, t2, isConstant, value, genCode,
checkConst);
structType,unionType:
if not CompTypes(t1, t2) then
Error(47);
otherwise: Error(57);
end; {case T1^.kind}
expressionType := t1; {set the type of the expression}
end; {AssignmentConversion}
function ExpressionTree (kind: expressionKind; stopSym: tokenSet): tokenPtr;
{ generate an expression tree }
{ }
{ Returns a pointer to the generated tree. The pointer is }
{ nil, and the variable errorFound is set to true, if an }
{ error is found. }
{ }
{ parameters: }
{ kind - Kind of expression; determines what operations }
{ and what kind of operands are allowed. }
{ stopSym - Set of symbols that can mark the end of an }
{ expression; used to skip tokens after syntax }
{ errors and to block certain operations. For }
{ example, the comma operator is not allowed in }
{ an expression when evaluating a function }
{ parameter list. }
label 1,2,3;
var
done,done2: boolean; {for loop termination}
doingSizeof: boolean; {used to test for a sizeof operator}
expectingTerm: boolean; {should the next token be a term?}
opStack: tokenPtr; {operation stack}
parenCount: integer; {# of open parenthesis}
stack: tokenPtr; {operand stack}
op,sp: tokenPtr; {work pointers}
procedure ComplexTerm;
{ handle complex terms }
var
done: boolean; {for loop termination}
namePtr: stringPtr; {name of struct/union fields}
sp,tp,tm: tokenPtr; {work pointers}
begin {ComplexTerm}
while token.kind in
[lbrackch,lparench,dotch,minusgtop,plusplusop,minusminusop] do begin
case token.kind of
lbrackch: begin {subscripting}
NextToken; {skip the '['}
new(sp); {evaluate the subscript}
sp^.token.kind := plusch;
sp^.token.class := reservedSymbol;
sp^.left := stack;
stack := stack^.next;
sp^.middle := nil;
sp^.right := ExpressionTree(normalExpression, [rbrackch]);
sp^.next := stack;
stack := sp;
Match(rbrackch,24); {skip the ']'}
new(sp); {resolve the pointer}
sp^.token.kind := uasterisk;
sp^.token.class := reservedSymbol;
sp^.left := stack;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack^.next;
stack := sp;
end;
lparench: begin {function call}
NextToken;
new(sp); {create a parameter list terminator}
sp^.token.kind := parameteroper;
sp^.token.class := reservedSymbol;
sp^.left := nil;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack;
stack := sp;
if token.kind <> rparench {evaluate the parameters}
then begin
done := false;
repeat
if token.kind in [rparench,eofsy] then begin
done := true;
Error(35);
end {if}
else begin
new(sp);
sp^.token.kind := parameteroper;
sp^.token.class := reservedSymbol;
sp^.left := nil;
sp^.middle :=
ExpressionTree(normalExpression, [rparench,commach]);
sp^.right := stack;
sp^.next := stack^.next;
stack := sp;
if token.kind = commach then
NextToken
else
done := true;
end; {else}
until done;
end; {if}
sp := stack;
stack := sp^.next;
sp^.left := stack;
sp^.next := stack^.next;
stack := sp;
Match(rparench,12);
end;
dotch,minusgtop: begin {direct and indirect selection}
if token.kind = minusgtop then begin
new(sp); {e->name == (*e).name}
sp^.token.kind := uasterisk;
sp^.token.class := reservedSymbol;
sp^.left := stack;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack^.next;
stack := sp;
token.kind := dotch;
token.class := reservedSymbol;
end; {if}
new(sp); {create a record for the selection operator}
sp^.token := token;
sp^.left := stack;
stack := stack^.next;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack;
stack := sp;
NextToken; {skip the operator}
if token.kind in [ident,typedef] then begin
namePtr := token.name; {record the name}
new(sp); {record the selection field}
sp^.token := token;
sp^.left := nil;
sp^.middle := nil;
sp^.right := nil;
stack^.right := sp; {this becomes the right opnd}
NextToken; {skip the field name}
end {if}
else
Error(9);
end;
plusplusop: begin {postfix ++}
NextToken;
new(sp);
sp^.token.kind := opplusplus;
sp^.token.class := reservedSymbol;
sp^.left := stack;
stack := stack^.next;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack;
stack := sp;
end;
minusminusop: begin {postfix --}
NextToken;
new(sp);
sp^.token.kind := opminusminus;
sp^.token.class := reservedSymbol;
sp^.left := stack;
stack := stack^.next;
sp^.middle := nil;
sp^.right := nil;
sp^.next := stack;
stack := sp;
end;
otherwise: Error(57);
end; {case}
end; {while}
end; {ComplexTerm}
procedure DoOperand;
{ process an operand }
label 1,2;
var
fnPtr: typePtr; {for defining functions on the fly}
fToken: tokenType; {used to save function name token}
id: identPtr; {pointer to an id's symbol table entry}
np: stringPtr; {for forming global names}
sp: tokenPtr; {work pointer}
begin {DoOperand}
{create an operand on the stack}
new(sp);
sp^.token := token;
sp^.next := stack;
sp^.left := nil;
sp^.middle := nil;
sp^.right := nil;
stack := sp;
{handle the preprocessor 'defined' function}
if kind = preprocessorExpression then
if token.name^ = 'defined' then begin
expandMacros := false;
NextToken;
sp^.token.kind := intconst;
sp^.token.class := intConstant;
if token.kind in [ident,typedef] then begin
sp^.token.ival := ord(IsDefined(token.name));
NextToken;
end {if}
else begin
Match(lparench, 13);
if token.kind in [ident,typedef] then begin
sp^.token.ival := ord(IsDefined(token.name));
NextToken;
end {if}
else begin
Error(9);
sp^.token.ival := 0;
end; {else}
Match(rparench, 12);
end; {else}
expandMacros := true;
goto 1;
end; {if}
{check for illegal use}
id := FindSymbol(token, variableSpace, false, true);
if not (kind in
[normalExpression,initializerExpression,autoInitializerExpression])
then begin
if id <> nil then
if id^.itype^.kind = enumConst then
goto 2;
if kind <> preprocessorExpression then begin
op := opStack;
while op <> nil do begin
if op^.token.kind = sizeofsy then
goto 2;
op := op^.next;
end; {while}
Error(41);
errorFound := true;
end; {if}
end; {if}
2:
{skip the name}
fToken := token;
NextToken;
{if the id is not declared, create a function returning integer}
if id = nil then begin
if token.kind = lparench then begin
fnPtr := pointer(GCalloc(sizeof(typeRecord)));
{fnPtr^.size := 0;}
{fnPtr^.saveDisp := 0;}
{fnPtr^.isConstant := false;}
fnPtr^.kind := functionType;
fnPtr^.fType := wordPtr;
{fnPtr^.varargs := false;}
{fnPtr^.prototyped := false;}
{fnPtr^.overrideKR := false;}
{fnPtr^.parameterList := nil;}
{fnPtr^.isPascal := false;}
{fnPtr^.toolNum := 0;}
{fnPtr^.dispatcher := 0;}
np := pointer(GMalloc(length(fToken.name^)+1));
CopyString(pointer(np), pointer(fToken.name));
id := NewSymbol(np, fnPtr, ident, variableSpace, declared);
if (lint & lintUndefFn) <> 0 then
Error(51);
end {if}
else if kind = preprocessorExpression then begin
stack^.token.kind := intconst;
stack^.token.ival := 0;
end {else if}
else begin
Error(31);
errorFound := true;
end; {else}
end {if id = nill}
else if id^.itype^.kind = enumConst then begin
stack^.token.kind := intconst;
stack^.token.ival := id^.itype^.eval;
end; {else if}
stack^.id := id; {save the identifier}
ComplexTerm; {handle subscripts, selection, etc.}
1:
end; {DoOperand}
procedure Operation;
{ do an operation }
label 1;
var
baseType: baseTypeEnum; {base type of value to cast}
class: tokenClass; {class of cast token}
ekind: tokenEnum; {kind of constant expression}
kindLeft, kindRight: tokenEnum; {kinds of operands}
lCodeGeneration: boolean; {local copy of codeGeneration}
op: tokenPtr; {work pointer}
op1,op2: longint; {for evaluating constant expressions}
rop1,rop2: double; {for evaluating double expressions}
tp: typePtr; {cast type}
unsigned, unsigned1: boolean; {is the term unsigned?}
function Pop: tokenPtr;
{ pop an operand, returning its pointer }
begin {Pop}
if stack = nil then begin
Error(36);
errorFound := true;
Pop := nil;
end {if}
else begin
Pop := stack;
stack := stack^.next;
end; {else}
end; {Pop}
function RealVal (token: tokenType): double;
{ convert an operand to a real value }
begin {RealVal}
if token.kind = intconst then
RealVal := token.ival
else if token.kind = uintconst then begin
if token.ival < 0 then
RealVal := (token.ival & $7FFF) + 32768.0
else
RealVal := token.ival;
end {else if}
else if token.kind = longconst then
RealVal := token.lval
else if token.kind = ulongconst then begin
if token.lval < 0 then
RealVal := (token.lval & $7FFFFFFF) + 2147483648.0
else
RealVal := token.lval;
end {else if}
else
RealVal := token.rval;
end; {RealVal}
function IntVal (token: tokenType): longint;
{ convert an operand to a longint value }
begin {IntVal}
if token.kind = intconst then
IntVal := token.ival
else if token.kind = uintconst then begin
IntVal := token.ival & $0000FFFF;
unsigned := true;
end {else if}
else if token.kind = longconst then begin
IntVal := token.lval;
ekind := longconst;
end {else if}
else begin
IntVal := token.lval;
ekind := longconst;
unsigned := true;
end; {else}
end; {IntVal}
begin {Operation}
op := opStack; {pop the operation}
opStack := op^.next;
case op^.token.kind of
commach: begin {,}
op^.right := Pop;
op^.left := Pop;
end;
eqch, {=}
pluseqop, {+=}
minuseqop, {-=}
asteriskeqop, {*=}
slasheqop, {/=}
percenteqop, {%=}
ltlteqop, {<<=}
gtgteqop, {>>=}
andeqop, {&=}
caroteqop, {^=}
bareqop: begin {|=}
op^.right := Pop;
op^.left := Pop;
end;
colonch: begin {? :}
op^.right := Pop;
op^.middle := Pop;
op^.left := Pop;
if op^.right^.token.kind in
[intconst,uintconst,longconst,ulongconst] then
if op^.left^.token.kind in
[intconst,uintconst,longconst,ulongconst] then
if op^.middle^.token.kind in
[intconst,uintconst,longconst,ulongconst] then begin
if IntVal(op^.left^.token) <> 0 then
op^.token := op^.middle^.token
else
op^.token := op^.right^.token;
dispose(op^.left);
dispose(op^.right);
dispose(op^.middle);
op^.left := nil;
op^.right := nil;
op^.middle := nil;
end; {if}
end;
questionch: begin {error -> ? should not be unmatched}
Error(29);
errorFound := true;
end;
barbarop, {||}
andandop, {&&}
carotch, {^}
barch, {|}
andch, {&}
eqeqop, {==}
exceqop, {!=}
ltch, {<}
gtch, {>}
lteqop, {<=}
gteqop, {>=}
ltltop, {<<}
gtgtop, {>>}
plusch, {+}
minusch, {-}
asteriskch, {*}
slashch, {/}
percentch: begin {%}
op^.right := Pop;
op^.left := Pop;
kindRight := op^.right^.token.kind;
kindLeft := op^.left^.token.kind;
if kindRight in [intconst,uintconst,longconst,ulongconst] then begin
if kindLeft in [intconst,uintconst,longconst,ulongconst] then begin
{do the usual binary conversions}
if (kindRight = ulongconst) or (kindLeft = ulongconst) then
ekind := ulongconst
else if (kindRight = longconst) or (kindLeft = longconst) then
ekind := longconst
else if (kindRight = uintconst) or (kindLeft = uintconst) then
ekind := uintconst
else
ekind := intconst;
{evaluate a constant operation}
unsigned := false;
op1 := IntVal(op^.left^.token);
unsigned1 := unsigned;
unsigned := false;
op2 := IntVal(op^.right^.token);
unsigned := unsigned or unsigned1;
dispose(op^.right);
op^.right := nil;
dispose(op^.left);
op^.left := nil;
case op^.token.kind of
barbarop : {||}
op1 := ord((op1 <> 0) or (op2 <> 0));
andandop : {&&}
op1 := ord((op1 <> 0) and (op2 <> 0));
carotch : op1 := op1 ! op2; {^}
barch : op1 := op1 | op2; {|}
andch : op1 := op1 & op2; {&}
eqeqop : begin {==}
op1 := ord(op1 = op2);
ekind := intconst;
end;
exceqop : begin {!=}
op1 := ord(op1 <> op2);
ekind := intconst;
end;
ltch : begin {<}
if unsigned then
op1 := ult(op1,op2)
else
op1 := ord(op1 < op2);
ekind := intconst;
end;
gtch : begin {>}
if unsigned then
op1 := ugt(op1,op2)
else
op1 := ord(op1 > op2);
ekind := intconst;
end;
lteqop : begin {<=}
if unsigned then
op1 := ule(op1,op2)
else
op1 := ord(op1 <= op2);
ekind := intconst;
end;
gteqop : begin {>=}
if unsigned then
op1 := uge(op1,op2)
else
op1 := ord(op1 >= op2);
ekind := intconst;
end;
ltltop : op1 := op1 << op2; {<<}
gtgtop : if unsigned1 then {>>}
op1 := lshr(op1,op2)
else
op1 := op1 >> op2;
plusch : op1 := op1 + op2; {+}
minusch : op1 := op1 - op2; {-}
asteriskch : if unsigned then {*}
op1 := umul(op1,op2)
else
op1 := op1 * op2;
slashch : begin {/}
if op2 = 0 then begin
Error(109);
op2 := 1;
end; {if}
if unsigned then
op1 := udiv(op1,op2)
else
op1 := op1 div op2;
end;
percentch : begin {%}
if op2 <= 0 then begin
Error(109);
op2 := 1;
end; {if}
if unsigned then
op1 := umod(op1,op2)
else
op1 := op1 mod op2;
end;
otherwise: Error(57);
end; {case}
op^.token.kind := ekind;
if ekind in [longconst,ulongconst] then begin
op^.token.lval := op1;
op^.token.class := longConstant;
end {if}
else begin
op^.token.ival := long(op1).lsw;
op^.token.class := intConstant;
end; {else}
goto 1;
end; {if}
end; {if}
if op^.right^.token.kind in
[intconst,uintconst,longconst,ulongconst,doubleconst] then
if op^.left^.token.kind in
[intconst,uintconst,longconst,ulongconst,doubleconst] then
begin
ekind := doubleconst; {evaluate a constant operation}
rop1 := RealVal(op^.left^.token);
rop2 := RealVal(op^.right^.token);
dispose(op^.right);
op^.right := nil;
dispose(op^.left);
op^.left := nil;
case op^.token.kind of
barbarop : {||}
rop1 := ord((rop1 <> 0.0) or (rop2 <> 0.0));
andandop : {&&}
rop1 := ord((rop1 <> 0.0) and (rop2 <> 0.0));
eqeqop : begin {==}
op1 := ord(rop1 = rop2);
ekind := intconst;
end;
exceqop : begin {!=}
op1 := ord(rop1 <> rop2);
ekind := intconst;
end;
ltch : begin {<}
op1 := ord(rop1 < rop2);
ekind := intconst;
end;
gtch : begin {>}
op1 := ord(rop1 > rop2);
ekind := intconst;
end;
lteqop : begin {<=}
op1 := ord(rop1 <= rop2);
ekind := intconst;
end;
gteqop : begin {>=}
op1 := ord(rop1 >= rop2);
ekind := intconst;
end;
plusch : rop1 := rop1 + rop2; {+}
minusch : rop1 := rop1 - rop2; {-}
asteriskch : rop1 := rop1 * rop2; {*}
slashch : begin {/}
if rop2 = 0.0 then begin
Error(109);
rop2 := 1.0;
end; {if}
rop1 := rop1 / rop2;
end;
otherwise : Error(66); {illegal operation}
end; {case}
if ekind = intconst then begin
op^.token.ival := long(op1).lsw;
op^.token.class := intConstant;
op^.token.kind := intConst;
end {if}
else begin
op^.token.rval := rop1;
op^.token.class := doubleConstant;
op^.token.kind := doubleConst;
end; {else}
end; {if}
1:
end;
plusplusop, {prefix ++}
minusminusop, {prefix --}
opplusplus, {postfix ++}
opminusminus, {postfix --}
sizeofsy, {sizeof}
castoper, {(type)}
typedef, {(type-name)}
tildech, {~}
excch, {!}
uminus, {unary -}
uand, {unary &}
uasterisk: begin {unary *}
op^.left := Pop;
if op^.token.kind = sizeofsy then begin
op^.token.kind := longConst;
op^.token.class := longConstant;
if op^.left^.token.kind = stringConst then
op^.token.lval := op^.left^.token.sval^.length+1
else begin
lCodeGeneration := codeGeneration;
codeGeneration := false;
GenerateCode(op^.left);
codeGeneration := lCodeGeneration and (numErrors = 0);
op^.token.lval := expressionType^.size;
with expressionType^ do
if kind = arrayType then
if (elements = 0) or (size = 0) then
Error(49);
end; {else}
op^.left := nil;
end {if sizeofsy}
else if op^.token.kind = castoper then begin
class := op^.left^.token.class;
if class in [intConstant,longConstant,doubleConstant] then begin
tp := op^.castType;
while tp^.kind = definedType do
tp := tp^.dType;
if tp^.kind = scalarType then begin
baseType := tp^.baseType;
if baseType < cgString then begin
if class = doubleConstant then begin
rop1 := RealVal(op^.left^.token);
op1 := trunc(rop1);
end {if}
else {if class in [intConstant,longConstant] then} begin
op1 := IntVal(op^.left^.token);
if op1 >= 0 then
rop1 := op1
else if op^.left^.token.kind = uintConst then
rop1 := (op1 & $7FFF) + 32768.0
else if op^.left^.token.kind = ulongConst then
rop1 := (op1 & $7FFFFFFF) + 2147483648.0
else
rop1 := op1;
end; {else if}
dispose(op^.left);
op^.left := nil;
if baseType in [cgByte,cgWord] then begin
op^.token.kind := intConst;
op^.token.class := intConstant;
op^.token.ival := long(op1).lsw;
if baseType = cgByte then
with op^.token do begin
ival := ival & $00FF;
if (ival & $0080) <> 0 then
ival := ival | $FF00;
end; {with}
end {if}
else if baseType in [cgUByte,cgUWord] then begin
op^.token.kind := uintConst;
op^.token.class := intConstant;
op^.token.ival := long(op1).lsw;
if baseType = cgUByte then
op^.token.ival := op^.token.ival & $00FF;
end {else if}
else if baseType = cgLong then begin
op^.token.kind := longConst;
op^.token.class := longConstant;
op^.token.lval := op1;
end {else if}
else if baseType = cgULong then begin
op^.token.kind := ulongConst;
op^.token.class := longConstant;
op^.token.lval := op1;
end {else if}
else begin
op^.token.kind := doubleConst;
op^.token.class := doubleConstant;
op^.token.rval := rop1;
end; {else if}
end; {if}
end; {if}
end; {if}
end {else if castoper}
else if not (op^.token.kind in
[typedef,plusplusop,minusminusop,opplusplus,opminusminus,uand]) then
begin
if (op^.left^.token.kind
in [intconst,uintconst,longconst,ulongconst]) then begin
{evaluate a constant operation}
ekind := op^.left^.token.kind;
op1 := IntVal(op^.left^.token);
dispose(op^.left);
op^.left := nil;
case op^.token.kind of
opplusplus, {posfix ++}
plusplusop : op1 := op1+1; {prefix ++}
opminusminus, {postfix --}
minusminusop: op1 := op1-1; {prefix --}
tildech : op1 := ~op1; {~}
excch : begin {!}
op1 := ord(op1 = 0);
ekind := intconst;
end;
uminus : op1 := -op1; {unary -}
uand : op1 := 0; {unary &}
uasterisk : op1 := 0; {unary *}
otherwise: Error(57);
end; {case}
op^.token.kind := ekind;
if ekind in [longconst,ulongconst] then begin
op^.token.class := longConstant;
op^.token.lval := op1;
end {if}
else begin
op^.token.class := intConstant;
op^.token.ival := long(op1).lsw;
end; {else}
end {if}
else if op^.left^.token.kind = doubleconst then begin
ekind := doubleconst; {evaluate a constant operation}
rop1 := RealVal(op^.left^.token);
dispose(op^.left);
op^.left := nil;
case op^.token.kind of
uminus : begin {unary -}
op^.token.class := doubleConstant;
op^.token.kind := doubleConst;
op^.token.rval := -rop1;
end;
otherwise : begin {illegal operation}
Error(66);
op^.token.class := doubleConstant;
op^.token.kind := doubleConst;
op^.token.rval := rop1;
end;
end; {case}
end; {if}
end; {if}
end;
otherwise: Error(57);
end; {case}
op^.next := stack; {place the operation on the operand stack}
stack := op;
end; {Operation}
procedure Skip;
{ skip all tokens in the reminader of the expression }
begin {Skip}
while not (token.kind in stopSym+[eofsy]) do
NextToken;
errorFound := true;
end; {Skip}
procedure TypeName;
{ find the type (used for casts and sizeof) }
{ }
{ outputs: }
{ typeSpec - pointer to the type }
var
tl,tp: typePtr; {for creating/reversing the type list}
procedure AbstractDeclarator;
{ process an abstract declarator }
{ }
{ abstract-declarator: }
{ empty-abstract-declarator }
{ nonempty-abstract-declarator }
procedure NonEmptyAbstractDeclarator;
{ process a nonempty abstract declarator }
{ }
{ nonempty-abstract-declarator: }
{ ( nonempty-abstract-declarator ) }
{ abstract-declarator ( ) }
{ abstract-declaraotr [ expression OPT ] }
{ * abstract-declarator }
var
pcount: integer; {paren counter}
tp: typePtr; {work pointer}
begin {NonEmptyAbstractDeclarator}
if token.kind = lparench then begin
NextToken;
if token.kind = rparench then begin
{create a function type}
tp := pointer(Calloc(sizeof(typeRecord)));
{tp^.size := 0;}
{tp^.saveDisp := 0;}
{tp^.isConstant := false;}
tp^.kind := functionType;
{tp^.varargs := false;}
{tp^.prototyped := false;}
{tp^.overrideKR := false;}
{tp^.parameterList := nil;}
{tp^.isPascal := false;}
{tp^.toolNum := 0;}
{tp^.dispatcher := 0;}
tp^.fType := tl;
tl := tp;
NextToken;
end {if}
else begin
{handle a perenthesized type}
if not (token.kind in [lparench,asteriskch,lbrackch]) then
begin
Error(82);
while not (token.kind in
[eofsy,lparench,asteriskch,lbrackch,rparench]) do
NextToken;
errorFound := true;
end; {if}
if token.kind in [lparench,asteriskch,lbrackch] then
NonEmptyAbstractDeclarator;
Match(rparench,12);
end; {else}
end {if token.kind = lparench}
else if token.kind = asteriskch then begin
{create a pointer type}
NextToken;
AbstractDeclarator;
tp := pointer(Malloc(sizeof(typeRecord)));
tp^.size := cgLongSize;
tp^.saveDisp := 0;
tp^.isConstant := false;
tp^.kind := pointerType;
tp^.fType := tl;
tl := tp;
end {else if token.kind = asteriskch}
else {if token.kind = lbrackch then} begin
{create an array type}
NextToken;
if token.kind = rbrackch then
expressionValue := 0
else begin
Expression(arrayExpression, [rbrackch]);
if expressionValue <= 0 then begin
Error(45);
expressionValue := 1;
end; {if}
end; {else}
tp := pointer(Malloc(sizeof(typeRecord)));
tp^.saveDisp := 0;
tp^.kind := arrayType;
tp^.elements := expressionValue;
tp^.fType := tl;
tl := tp;
Match(rbrackch,24);
end; {else}
if token.kind = lparench then begin
{create a function type}
NextToken;
pcount := 1;
while (token.kind <> eofsy) and (pcount <> 0) do begin
if token.kind = rparench then
pcount := pcount-1
else if token.kind = lparench then
pcount := pcount+1;
NextToken;
end; {while}
tp := pointer(Calloc(sizeof(typeRecord)));
{tp^.size := 0;}
{tp.saveDisp := 0;}
{tp^.isConstant := false;}
tp^.kind := functionType;
{tp^.varargs := false;}
{tp^.prototyped := false;}
{tp^.overrideKR := false;}
{tp^.parameterList := nil;}
{tp^.isPascal := false;}
{tp^.toolNum := 0;}
{tp^.dispatcher := 0;}
tp^.fType := tl;
tl := tp;
end; {if}
end; {NonEmptyAbstractDeclarator}
begin {AbstractDeclarator}
while token.kind in [lparench,asteriskch,lbrackch] do
NonEmptyAbstractDeclarator;
end; {AbstractDeclarator}
begin {TypeName}
{read and process the type specifier}
typeSpec := wordPtr;
TypeSpecifier(false,false);
{handle the abstract-declarator part}
tl := nil; {no types so far}
AbstractDeclarator; {create the type list}
while tl <> nil do begin {reverse the list & compute array sizes}
tp := tl^.aType; {NOTE: assumes aType, pType and fType overlap in typeRecord}
tl^.aType := typeSpec;
if tl^.kind = arrayType then
tl^.size := tl^.elements * typeSpec^.size;
typeSpec := tl;
tl := tp;
end; {while}
end; {TypeName}
begin {ExpressionTree}
opStack := nil;
stack := nil;
if token.kind = typedef then {handle typedefs that are hidden}
if FindSymbol(token,allSpaces,false,true) <> nil then
if token.symbolPtr^.class <> typedefsy then
token.kind := ident;
if token.kind in startExpression then begin
expressionValue := 0; {initialize the expression value}
expectingTerm := true; {the first item should be a term}
done := false; {convert the expression to postfix form}
parenCount := 0;
repeat {scan the token list...}
if token.kind in startTerm then begin
{we must expect a term or unary operand}
if not expectingTerm then begin
Error(36);
Skip;
goto 1;
end; {if}
if token.kind = ident then
{handle a complex operand}
DoOperand
else begin
{handle a constant operand}
new(sp);
sp^.token := token;
sp^.next := stack;
sp^.left := nil;
sp^.middle := nil;
sp^.right := nil;
stack := sp;
if kind in [preprocessorExpression,arrayExpression] then
if token.kind in [stringconst,doubleconst] then begin
if kind = arrayExpression then begin
op := opStack;
while op <> nil do begin
if op^.token.kind = sizeofsy then
goto 3;
op := op^.next;
end; {while}
end; {if}
Error(41);
errorFound := true;
end; {if}
3:
NextToken;
ComplexTerm;
end; {else}
expectingTerm := false; {the next thing should be an operation}
end {else}
{handle a closing parenthesis}
else if (token.kind = rparench) and (parenCount > 0) then begin
if expectingTerm then begin {make sure it is in a legal spot}
Error(37);
Skip;
goto 1;
end; {if}
while opStack^.token.kind <> lparench do
Operation; {do pending operations}
op := opStack;
opStack := op^.next;
dispose(op);
parenCount := parenCount-1;
NextToken; {skip the ')'}
ComplexTerm; {handle subscripts, selection, etc.}
end {else}
else if token.kind = lparench then begin
{handle open paren and type casts}
if not expectingTerm then begin
Error(38);
Skip;
goto 1;
end; {if}
NextToken;
if token.kind in [unsignedsy,intsy,longsy,charsy,shortsy,floatsy,
doublesy,compsy,extendedsy,voidsy,enumsy,structsy,unionsy,
typedef,constsy,volatilesy,signedsy] then begin
doingSizeof := false;
if opStack <> nil then
if opStack^.token.kind = sizeofsy then
doingSizeof := true;
TypeName;
if doingSizeof then begin
{handle a sizeof operator}
op := opStack;
opStack := op^.next;
dispose(op);
new(sp);
sp^.next := stack;
sp^.left := nil;
sp^.middle := nil;
sp^.right := nil;
sp^.token.kind := longconst;
sp^.token.class := longConstant;
sp^.token.lval := typeSpec^.size;
if typeSpec^.kind = arrayType then
if (typeSpec^.elements = 0) or (typeSpec^.size = 0) then
Error(49);
sp^.next := stack;
stack := sp;
expectingTerm := false;
end {if}
else {doing a cast} begin
{handle a type cast}
new(op); {stack the cast operator}
op^.left := nil;
op^.middle := nil;
op^.right := nil;
op^.castType := typeSpec;
op^.token.kind := castoper;
op^.token.class := reservedWord;
op^.next := opStack;
opStack := op;
end; {else}
Match(rparench,12);
end {if}
else begin
new(op); {record the '('}
op^.next := opStack;
op^.left := nil;
op^.middle := nil;
op^.right := nil;
opStack := op;
op^.token.kind := lparench;
op^.token.class := reservedSymbol;
parenCount := parenCount+1;
end;
end {else if}
else begin {handle an operation...}
if expectingTerm then {convert unary operators to separate tokens}
if token.kind in [asteriskch,minusch,plusch,andch] then
case token.kind of
asteriskch: token.kind := uasterisk;
minusch : token.kind := uminus;
andch : token.kind := uand;
plusch : begin
NextToken;
goto 2;
end;
otherwise : Error(57);
end; {case}
if icp[token.kind] = notAnOperation then
done := true {end of expression found...}
else if (token.kind in stopSym) and (parenCount = 0) then
done := true
else begin
if not (kind in [normalExpression, autoInitializerExpression]) then
if (token.kind in
[plusplusop,minusminusop,eqch,pluseqop,minuseqop,
opplusplus,opminusminus,
asteriskeqop,slasheqop,percenteqop,ltlteqop,
gtgteqop,caroteqop,bareqop,commach])
or ((kind = preprocessorExpression)
and (token.kind = sizeofsy))
or ((kind <> initializerExpression)
and (token.kind = uand)) then begin
Error(40);
errorFound := true;
end; {if}
if token.kind in {make sure we get what we want}
[plusplusop,minusminusop,sizeofsy,tildech,excch,
uasterisk,uminus,uand] then begin
if not expectingTerm then begin
Error(38);
Skip;
goto 1;
end; {if}
end {if}
else begin
if expectingTerm then begin
Error(37);
Skip;
goto 1;
end; {if}
expectingTerm := true;
{handle 2nd half of ternary operator}
if token.kind = colonch then begin
done2 := false; {do pending operations}
repeat
if opStack = nil then
done2 := true
else if opStack^.token.kind <> questionch then
Operation
else
done2 := true;
until done2;
if (opStack = nil) or
(opStack^.token.kind <> questionch) then begin
Error(39);
Skip;
goto 1;
end; {if}
op := opStack;
opStack := op^.next;
dispose(op);
end {if}
else begin
done2 := false; {do operations with less precidence}
repeat
if opStack = nil then
done2 := true
else if isp[opStack^.token.kind] >= icp[token.kind] then
Operation
else
done2 := true;
until done2;
end; {else}
end; {else}
new(op); {record the operation}
op^.next := opStack;
op^.left := nil;
op^.middle := nil;
op^.right := nil;
opStack := op;
op^.token := token;
NextToken;
end; {else}
end; {else}
2:
until done;
if parenCount > 0 then begin
Error(12);
errorFound := true;
end {if}
else begin
while opStack <> nil do {do pending operations}
Operation;
{there should be exactly one operand left}
if (stack = nil) or (stack^.next <> nil) then begin
Error(36);
errorFound := true;
end; {if}
end; {else}
end {if}
else begin {the start of an expression was not found}
Error(35);
if not (token.kind in stopSym) then
NextToken;
Skip;
end; {else}
1:
if errorFound then begin
while opStack <> nil do begin
op := opStack;
opStack := op^.next;
dispose(op);
end; {while}
while stack <> nil do begin
sp := stack;
stack := sp^.next;
DisposeTree(sp);
end; {while}
ExpressionTree := nil;
end {if}
else
ExpressionTree := stack;
end; {ExpressionTree}
procedure CompareToZero {op: pcodes};
{ Compare the result on tos to zero. }
{ }
{ This procedure is used by the logical statements to compare }
{ _any_ scalar result to zero, giving a boolean result. }
{ }
{ parameters: }
{ op - operation to use on the compare }
var
bt: baseTypeEnum; {base type of loaded value}
begin {CompareToZero}
if expressionType^.kind in [pointerType,arrayType] then
expressionType := uLongPtr;
if expressionType^.kind = scalarType then begin
bt := UsualUnaryConversions;
case bt of
cgByte,cgUByte,cgWord,cgUWord:
Gen1t(pc_ldc, 0, cgWord);
cgLong,cgULong:
GenLdcLong(0);
cgReal,cgDouble,cgComp,cgExtended:
GenLdcReal(0.0);
otherwise:
Error(47);
end; {case}
expressionType := wordPtr;
Gen0t(op, bt);
end {if}
else
Error(47);
end; {CompareToZero}
procedure FreeTemp{labelNum, size: integer};
{ place a temporary label in the available label list }
{ }
{ parameters: }
{ labelNum - number of the label to free }
{ size - size of the variable }
{ }
{ variables: }
{ tempList - list of free labels }
var
tl: tempPtr; {work pointer}
begin {FreeTemp}
new(tl);
tl^.next := tempList;
tl^.last := nil;
tl^.labelNum := labelNum;
tl^.size := size;
if tempList <> nil then
tempList^.last := tl;
tempList := tl;
end; {FreeTemp}
function GetTemp{size: integer): integer};
{ find a temporary work variable }
{ }
{ parameters: }
{ size - size of the variable }
{ }
{ variables: }
{ tempList - list of free labels }
{ }
{ Returns the label number. }
label 1;
var
lcodeGeneration: boolean; {local copy of codeGeneration}
ln: integer; {label number}
tl: tempPtr; {work pointer}
begin {GetTemp}
{try to find a temp from the existing list}
tl := tempList;
while tl <> nil do begin
if tl^.size = size then begin
{found an old one - use it}
if tl^.last = nil then
tempList := tl^.next
else
tl^.last^.next := tl^.next;
if tl^.next <> nil then
tl^.next^.last := tl^.last;
GetTemp := tl^.labelNum;
goto 1;
end; {if}
tl := tl^.next;
end; {while}
{none found - get a new one}
ln := GetLocalLabel;
GetTemp := ln;
lcodeGeneration := codeGeneration;
codeGeneration := true;
Gen2(dc_loc, ln, size);
codeGeneration := lCodeGeneration and (numErrors = 0);
1:
end; {GetTemp}
procedure LoadScalar (id: identPtr);
{ Load a scalar value. }
{ }
{ parameters: }
{ id - ident for value to load }
var
tp: baseTypeEnum; {base type}
begin {LoadScalar}
if id^.itype^.kind = pointerType then
tp := cgULong
else
tp := id^.itype^.baseType;
case id^.storage of
stackFrame, parameter:
Gen2t(pc_lod, id^.lln, 0, tp);
external, global, private:
Gen1tName(pc_ldo, 0, tp, id^.name);
otherwise: ;
end; {case}
end; {LoadScalar}
procedure Cast(tp: typePtr);
{ Cast the current expression to the stated type }
{ }
{ parameters: }
{ tp - type to cast to }
{ }
{ inputs: }
{ expressionType - type of the expression to cast }
{ }
{ outputs: }
{ expressionType - set to result type }
var
et,rt: baseTypeEnum; {work variables}
begin {Cast}
if (tp^.kind = scalarType) and (expressionType^.kind = scalarType) then begin
rt := tp^.baseType;
et := expressionType^.baseType;
if rt <> et then
if et <> cgVoid then
Gen2(pc_cnv, ord(et), ord(rt))
else
Error(40);
end {if}
else if (tp^.kind = enumType) and (expressionType^.kind = scalarType) then begin
if expressionType^.baseType <> cgVoid then begin
rt := cgWord;
et := Unary(expressionType^.baseType);
if rt <> et then
Gen2(pc_cnv, ord(et), ord(rt));
end {if}
else
Error(40);
end {if}
else if (tp^.kind = scalarType) and (expressionType^.kind = enumType) then begin
rt := Unary(tp^.baseType);
et := cgWord;
if rt <> et then
Gen2(pc_cnv, ord(et), ord(rt));
end {if}
else if tp^.kind = pointerType then begin
case expressionType^.kind of
scalarType:
if expressionType^.baseType in
[cgByte,cgUByte,cgWord,cgUWord,cgLong,cgULong] then
Gen2(pc_cnv, ord(Unary(expressionType^.baseType)),
ord(cgULong))
else if doDispose then
Error(40);
arrayType,pointerType: ;
functionType,enumConst,enumType,definedType,structType,unionType:
if doDispose then
Error(40);
otherwise: Error(57);
end; {case}
end {else if}
else if expressionType^.kind in [pointerType,arrayType] then begin
case tp^.kind of
scalarType:
if tp^.baseType in
[cgByte,cgUByte,cgWord,cgUWord,cgLong,cgULong] then
Gen2(pc_cnv, ord(cgULong),
ord(Unary(tp^.baseType)))
else if tp^.baseType = cgVoid then
Gen0t(pc_pop, UsualUnaryConversions)
else
Error(40);
otherwise:
Error(40);
end; {case}
end {else if}
else if expressionType^.kind in [structType,unionType] then begin
if tp^.kind = scalarType then
if tp^.baseType = cgVoid then
Gen0t(pc_pop, UsualUnaryConversions)
else Error(40)
else Error(40);
end {else if}
else
Error(40);
expressionType := tp;
end; {Cast}
procedure DoSelection {lType: typePtr; tree: tokenPtr; var size: longint};
{ Find the displacement & type for a selection operation }
{ }
{ parameters: }
{ lType - structure/union type }
{ tree - right-hand tree }
{ size - disp into the structure/union }
{ }
{ returned in non-local variables: }
{ bitDisp - displacement to bit field }
{ bitSize - size of bit field }
{ unsigned - is the bit field unsigned? }
{ isBitField - is the field a bit field? }
{ }
{ varaibles: }
{ expressionType - set to the type of the field }
label 1;
var
ip: identPtr; {for scanning for the field}
begin {DoSelection}
expressionType := wordPtr; {set defaults in case there is an error}
size := 0;
if tree^.token.class = identifier then begin
while lType^.kind = definedType do
lType := lType^.dType;
if lType^.kind in [structType,unionType] then begin
ip := lType^.fieldList; {find a matching field}
while ip <> nil do begin
if ip^.name^ = tree^.token.name^ then begin
if ip^.isForwardDeclared then
ResolveForwardReference(ip);
size := ip^.disp; {match found - record parameters}
expressionType := ip^.itype;
bitDisp := ip^.bitDisp;
bitSize := ip^.bitSize;
isBitField := (bitSize+bitDisp) <> 0;
unsigned := ip^.itype^.baseType in [cgUByte,cgUWord,cgULong];
goto 1;
end; {if}
ip := ip^.next;
end; {while}
Error(81);
end {if}
else
Error(80);
end; {if}
1:
end; {DoSelection}
procedure L_Value(tree: tokenPtr);
{ Check for an l-value }
{ }
{ parameters: }
{ tree - expression tree to check }
var
kind: tokenEnum; {for efficiency}
begin {L_Value}
kind := tree^.token.kind;
{A variable identifier is an l-value unless it is a function or }
{non-parameter array }
if kind = ident then begin
if tree^.id^.itype^.kind = arrayType then begin
if tree^.id^.storage <> parameter then
if doDispose then {prevent spurious errors}
Error(78);
end {if}
else if tree^.id^.itype^.kind in
[functionType,enumConst,enumType] then
if doDispose then {prevent spurious errors}
Error(78);
end {if}
{e.field is an l-value if and only if e is an l-value}
else if kind = dotch then
L_Value(tree^.left)
{Bypass cast operators }
{following test removed to flag bug for: }
{ int *p; long l; }
{ (long) p = l; }
{else if kind = castoper then
L_Value(tree^.left)}
{The result of an array subscript (a[i]), indirect selection, }
{or the indirection operator all show up as the uasterisk }
{operator at this point. All are l-values, but nothing else }
{not already allowed is an l-value. }
else if kind <> uasterisk then
if doDispose then {prevent spurious errors}
Error(78);
end; {L_Value}
procedure ChangePointer (op: pcodes; size: longint; tp: baseTypeEnum);
{ Add or subtract an integer to a pointer }
{ }
{ The stack has a pointer and an integer (integer on TOS). }
{ The integer is removed, multiplied by size, and either }
{ added to or subtracted from the pointer; the result }
{ replaces the pointer on the stack }
{ }
{ parameters: }
{ op - operation (pc_adl or pc_sbl) }
{ size - size of one pointer element }
{ tp - type of the integer operand }
begin {ChangePointer}
case tp of
cgByte,cgUByte,cgWord,cgUWord: begin
if (size = long(size).lsw) and (op = pc_adl)
and smallMemoryModel and (tp in [cgUByte,cgUWord]) then begin
Gen1t(pc_ldc, long(size).lsw, cgWord);
Gen0(pc_umi);
Gen0t(pc_ixa, cgUWord);
end {if}
else if smallMemoryModel and (size = long(size).lsw) then begin
Gen1t(pc_ldc, long(size).lsw, cgWord);
Gen0(pc_mpi);
Gen2(pc_cnv, ord(tp), ord(cgLong));
Gen0(op);
end {else if}
else begin
Gen2(pc_cnv, ord(tp), ord(cgLong));
GenLdcLong(size);
Gen0(pc_mpl);
Gen0(op);
end;
end;
cgLong,cgULong: begin
GenLdcLong(size);
if tp = cgLong then
Gen0(pc_mpl)
else
Gen0(pc_uml);
Gen0(op);
end;
otherwise:
Error(66);
end; {case}
end; {ChangePointer}
procedure GenerateCode {tree: tokenPtr};
{ generate code from a fully formed expression tree }
{ }
{ parameters: }
{ tree - top of the expression tree to generate code from }
{ }
{ variables: }
{ expressionType - result type of the expression }
var
doingScalar: boolean; {temp; for assignment operators}
et: baseTypeEnum; {temp storage for a base type}
i: integer; {loop variable}
isString: boolean; {was the ? : a string?}
lType: typePtr; {type of operands}
kind: typeKind; {temp type kind}
size: longint; {size of an array element}
t1: integer; {temporary work space label number}
tlastwasconst: boolean; {temp lastwasconst}
tlastconst: longint; {temp lastconst}
tp: tokenPtr; {work pointer}
tType: typePtr; {temp type of operand}
lbitDisp,lbitSize: integer; {for temp storage}
lisBitField: boolean;
function ExpressionKind (tree: tokenPtr): typeKind;
{ returns the type of an expression }
{ }
{ This subroutine is used to see if + and - operarions }
{ should do pointer addition. }
{ }
{ parameters: }
{ tree - top of the expression tree to check }
var
ldoDispose: boolean; {local copy of doDispose}
lcodeGeneration: boolean; {local copy of codeGeneration}
lexpressionType: typePtr; {local copy of expressionType}
begin {ExpressionKind}
ldoDispose := doDispose; {inhibit disposing of the tree}
doDispose := false;
lcodeGeneration := codeGeneration; {inhibit code generation}
codeGeneration := false;
lexpressionType := expressionType; {save the expression type}
GenerateCode(tree); {get the type}
ExpressionKind := expressionType^.kind;
doDispose := ldoDispose; {resore the volitile variables}
codeGeneration := lCodeGeneration and (numErrors = 0);
expressionType := lexpressionType;
end; {ExpressionKind}
procedure LoadAddress (tree: tokenPtr);
{ load the address of an l-value }
{ }
{ parameters: }
{ tree - top of the expression tree to load the }
{ address of }
{ }
{ variables: }
{ expressionType - result type of the expression }
{ isBitField - this variable is set to false so that }
{ it can be used to see if DoSelection was called }
{ and located a bit field }
label 1;
var
eType: typePtr; {work pointer}
i: integer; {loop variable}
size: longint; {disp in record}
tname: stringPtr; {temp name pointer}
begin {LoadAddress}
isBitField := false;
if tree^.token.kind = ident then begin
{load the address of an identifier}
with tree^.id^ do begin
tname := name;
if itype^.kind = functionType then begin
if itype^.isPascal then begin
tname := pointer(Malloc(length(name^)+1));
CopyString(pointer(tname), pointer(name));
for i := 1 to length(tname^) do
if tname^[i] in ['a'..'z'] then
tname^[i] := chr(ord(tname^[i]) & $5F);
end; {if}
end; {if}
case storage of
stackFrame: Gen2(pc_lda, lln, 0);
parameter: if itype^.kind = arrayType then
Gen2t(pc_lod, pln, 0, cgULong)
else
Gen2(pc_lda, pln, 0);
external,
global,
private: Gen1Name(pc_lao, 0, tname);
otherwise: ;
end; {case}
eType := pointer(Malloc(sizeof(typeRecord)));
eType^.size := cgLongSize;
eType^.saveDisp := 0;
eType^.isConstant := false;
eType^.kind := pointerType;
eType^.pType := iType;
expressionType := eType;
end; {with}
end {if}
else if tree^.token.kind = uasterisk then begin
{load the address of the item pointed to by the pointer}
GenerateCode(tree^.left);
isBitField := false;
end {else if}
else if tree^.token.kind = dotch then begin
{load the address of a field of a record}
LoadAddress(tree^.left);
eType := expressionType;
if eType^.kind in [arrayType,pointerType] then begin
if eType^.kind = arrayType then
eType := eType^.aType
else if eType^.kind = pointerType then
eType := eType^.pType;
DoSelection(eType, tree^.right, size);
if size <> 0 then
if size & $00007FFF = size then
Gen1t(pc_inc, long(size).lsw, cgULong)
else begin
GenLdcLong(size);
Gen0(pc_adl);
end; {else}
eType := pointer(Malloc(sizeof(typeRecord)));
eType^.size := cgLongSize;
eType^.saveDisp := 0;
eType^.isConstant := false;
eType^.kind := pointerType;
eType^.pType := expressionType;
expressionType := eType;
end {if}
else
Error(79);
end {else if}
else if tree^.token.kind = castoper then begin
{load the address of a field of a record}
LoadAddress(tree^.left);
expressionType := tree^.castType;
if expressionType^.kind <> arrayType then begin
eType := pointer(Malloc(sizeof(typeRecord)));
eType^.size := cgLongSize;
eType^.saveDisp := 0;
eType^.isConstant := false;
eType^.kind := pointerType;
eType^.pType := expressionType;
expressionType := eType;
end; {if}
end {else if}
else if ExpressionKind(tree) in [arrayType,pointerType] then
GenerateCode(tree)
else
if doDispose then {prevent spurious errors}
Error(78);
1:
end; {LoadAddress}
procedure DoIncDec (tree: tokenPtr; pc_l, pc_g, pc_i: pcodes);
{ do ++ and -- }
{ }
{ parameters: }
{ tree - tree to generate the instruction for }
{ pc_l - op code for a local ++ or -- }
{ pc_g - op code for a global ++ or -- }
{ pc_i - op code for an indirect ++ or -- }
label 1;
var
baseType: baseTypeEnum; {type of operation}
lSize: longint; {number to inc or dec by}
iSize: integer; {number to inc or dec by}
tp: baseTypeEnum; {type of operand}
procedure IncOrDec (inc: boolean);
{ Increment or decrement a number on TOS }
{ }
{ parameters: }
{ inc - increment the number? }
begin {IncOrDec}
case expressionType^.kind of
scalarType:
case tp of
cgByte,cgUByte,cgWord,cgUWord: begin
Gen1t(pc_ldc, 1, cgWord);
if inc then
Gen0(pc_adi)
else
Gen0(pc_sbi);
end;
cgLong,cgULong: begin
GenLdcLong(1);
if inc then
Gen0(pc_adl)
else
Gen0(pc_sbl);
end;
cgReal,cgDouble,cgComp,cgExtended: begin
GenLdcReal(1.0);
if inc then
Gen0(pc_adr)
else
Gen0(pc_sbr);
end;
otherwise: Error(57);
end; {case}
pointerType,arrayType: begin
GenldcLong(expressionType^.pType^.size);
if inc then
Gen0(pc_adl)
else
Gen0(pc_sbl);
end;
otherwise: ;
end; {case}
end; {IncOrDec}
begin {DoIncDec}
L_Value(tree);
with tree^.id^ do
if (tree^.token.kind = ident)
and ((iType^.kind in [scalarType,pointerType])
or ((iType^.kind = arrayType) and (storage = parameter))) then begin
{check for ++ or -- of a constant}
if iType^.isConstant then
Error(93);
{do an efficient ++ or -- on a named location}
if iType^.kind = scalarType then begin
iSize := 1;
baseType := iType^.baseType;
if baseType in [cgReal,cgDouble,cgComp,cgExtended] then begin
{do real inc or dec}
LoadScalar(tree^.id); {load the value}
tp := baseType;
expressionType := iType;
IncOrDec(pc_l in [pc_lli,pc_lil]); {do the ++ or --}
case storage of {save the result}
stackFrame, parameter:
Gen2t(pc_cop, lln, 0, baseType);
external, global, private:
Gen1tName(pc_cpo, 0, baseType, name);
otherwise: ;
end; {case}
{correct the value for postfix ops}
if pc_l in [pc_lli,pc_lld] then
IncOrDec(pc_l = pc_lld);
expressionType := doublePtr;
goto 1;
end; {if}
end {if}
else {if iType^.kind = pointerType then} begin
lSize := iType^.pType^.size;
if long(lSize).msw <> 0 then begin
{handle inc/dec of >64K}
LoadScalar(tree^.id);
GenLdcLong(lSize);
if pc_l in [pc_lli,pc_lil] then
Gen0(pc_adl)
else
Gen0(pc_sbl);
with tree^.left^.id^ do
case storage of
stackFrame, parameter:
Gen2t(pc_cop, lln, 0, cgULong);
external, global, private:
Gen1tName(pc_cpo, 0, cgULong, name);
otherwise: ;
end; {case}
if pc_l in [pc_lli,pc_lld] then begin
GenLdcLong(lSize);
if pc_l = pc_lld then
Gen0(pc_adl)
else
Gen0(pc_sbl);
end; {if}
goto 1;
end; {if}
baseType := cgULong;
iSize := long(lSize).lsw;
end; {else}
case storage of
stackFrame, parameter:
Gen2t(pc_l, lln, iSize, baseType);
external, global, private:
Gen2tName(pc_g, iSize, 0, baseType, name);
otherwise: ;
end; {case}
expressionType := itype;
end {if}
else begin
{do an indirect ++ or --}
LoadAddress(tree); {get the address to save to}
if expressionType^.kind = arrayType then
expressionType := expressionType^.aType
else if expressionType^.kind = pointerType then
expressionType := expressionType^.pType;
if expressionType^.kind = scalarType then
if expressionType^.baseType in [cgByte,cgUByte,cgWord,cgUWord] then
tp := expressionType^.baseType
else
tp := UsualUnaryConversions
else
tp := UsualUnaryConversions;
if tp in [cgByte,cgUByte,cgWord,cgUword] then
Gen0t(pc_i, tp) {do indirect inc/dec}
else begin
t1 := GetTemp(cgLongSize);
Gen2t(pc_str, t1, 0, cgULong);
Gen2t(pc_lod, t1, 0, cgULong);
Gen2t(pc_lod, t1, 0, cgULong);
FreeTemp(t1, cgLongSize);
Gen1t(pc_ind, 0, tp); {load the value}
IncOrDec(pc_l in [pc_lli,pc_lil]); {do the ++ or --}
if isBitField then {copy the value}
if bitDisp+bitSize > 16 then begin
Gen2t(pc_cbf, bitDisp, bitSize, cgLong);
Gen0t(pc_bno, cgLong);
end {if}
else begin
Gen2t(pc_cbf, bitDisp, bitSize, cgWord);
Gen0t(pc_bno, cgWord);
end {else}
else begin
Gen0t(pc_cpi, tp);
Gen0t(pc_bno, tp);
end; {else}
if pc_l in [pc_lli,pc_lld] then {correct the value for postfix ops}
IncOrDec(pc_l = pc_lld);
end; {else}
end; {else}
1:
end; {DoIncDec}
procedure FunctionCall (tree: tokenPtr);
{ generate the actual function call }
var
fName: stringPtr; {uppercase file name}
fntype: typePtr; {temp function type}
ftree: tokenPtr; {function address tree}
ftype: typePtr; {function type}
i: integer; {loop variable}
indirect: boolean; {is this an indirect call?}
ldoDispose: boolean; {local copy of doDispose}
lcodeGeneration: boolean; {local copy of codeGeneration}
procedure FunctionParms (parms: tokenPtr; fType: typePtr);
{ Generate a function call. }
{ }
{ parameters: }
{ parms - parameter list }
{ fType - function type }
var
kind: typeKind; {for expression kinds}
ldoDispose: boolean; {local copy of doDispose}
lnumErrors: integer; {number of errors before type check}
numParms: integer; {# of parameters generated}
parameters: parameterPtr; {next prototyped parameter}
pCount: integer; {# of parameters prototyped}
prototype: boolean; {is the function prototyped?}
tp,ltp: tokenPtr; {work pointers}
procedure Reverse;
{ Reverse the parameter list }
var
p1,p2,p3: tokenPtr; {work pointers}
begin {Reverse}
p3 := parms; {remove the last entry}
p1 := parms;
p2 := nil;
while p3^.right <> nil do begin
p2 := p3;
p3 := p3^.right;
end; {while}
if p2 <> nil then
p2^.right := nil
else
p1 := nil;
while p1 <> nil do begin {reverse the remaining parms}
p2 := p1;
p1 := p1^.right;
p2^.right := p3;
p3 := p2;
end; {while}
parms := p3;
end; {Reverse}
begin {FunctionParms}
{check the validity of the parameter list}
if ftype^.isPascal then {reverse parms for pascal calls}
Reverse;
tp := parms; {set up to check types}
prototype := ftype^.prototyped;
parameters := ftype^.parameterList;
pCount := 1;
while parameters <> nil do begin {count the prototypes}
pCount := pCount+1;
parameters := parameters^.next;
end; {while}
parameters := ftype^.parameterList;
if prototype then begin {check for wrong # of parms}
while tp <> nil do begin {count the parms}
pCount := pCount-1;
tp := tp^.right;
end; {while}
tp := parms;
if (pCount > 0) or ((pCount <> 0) and not ftype^.varargs) then
Error(85);
end; {if}
{generate the parameters}
numParms := 0;
lDoDispose := doDispose;
doDispose := false;
while tp <> nil do begin
if tp^.middle <> nil then begin
lnumErrors := numErrors;
kind := ExpressionKind(tp^.middle);
if numErrors = lnumErrors then
if kind in [structType,unionType] then begin
GenerateCode(tp^.middle);
if expressionType^.size & $FFFF8000 <> 0 then
Error(61);
Gen1t(pc_ldc, long(expressionType^.size).lsw, cgWord);
Gen0(pc_psh);
end {else if}
else
GenerateCode(tp^.middle);
if prototype then begin
if pCount = 0 then begin
if parameters <> nil then begin
AssignmentConversion(parameters^.parameterType,
expressionType, lastWasConst, lastConst, true, true);
end; {if}
parameters := parameters^.next;
end {if}
else
pCount := pCount+1;
end; {if}
Gen0t(pc_stk, UsualUnaryConversions);
if numParms <> 0 then
Gen0t(pc_bno, UsualUnaryConversions);
numParms := numParms+1;
end; {if}
ltp := tp;
tp := tp^.right;
end; {while}
doDispose := lDoDispose;
if numParms = 0 then
Gen0(pc_nop);
if ftype^.isPascal then {restore parm order}
Reverse;
if doDispose then begin {dispose of leaf nodes}
DisposeTree(parms^.middle);
DisposeTree(parms^.right);
end; {if}
end; {FunctionParms}
begin {FunctionCall}
{find the type of the function}
indirect := true; {assume an indirect call}
ftree := tree^.left; {get the function tree}
if ftree^.token.kind = ident then {check for direct calls}
if ftree^.id^.itype^.kind = functionType then begin
indirect := false;
fType := ftree^.id^.itype; {get the function type}
end; {if}
if indirect then begin {get type for indirect call}
ldoDispose := doDispose;
doDispose := false;
lcodeGeneration := codeGeneration;
codeGeneration := false;
GenerateCode(ftree);
doDispose := ldoDispose;
codeGeneration := lCodeGeneration and (numErrors = 0);
ftype := expressionType;
while ftype^.kind in [pointerType,arrayType] do
ftype := ftype^.ptype;
end; {if}
{make sure the identifier is really a function}
if ftype^.kind <> functionType then
Error(114)
else begin
{generate function parameters}
FunctionParms (tree, fType);
{generate the function call}
expressionType := ftype^.fType;
if expressionType^.kind in [structType,unionType] then
expressionType := uLongPtr;
if (ftype^.toolNum = 0) and (ftype^.dispatcher = 0) then begin
if indirect then begin
fntype := expressionType;
GenerateCode(ftree);
expressionType := fntype;
Gen1t(pc_cui, ord(fType^.varargs and strictVararg),
UsualUnaryConversions);
end {if}
else begin
fname := ftree^.id^.name;
if ftype^.isPascal then begin
fname := pointer(Malloc(length(fname^)+1));
CopyString(pointer(fname), pointer(ftree^.id^.name));
for i := 1 to length(fname^) do
if fName^[i] in ['a'..'z'] then
fName^[i] := chr(ord(fName^[i]) & $5F);
end; {if}
Gen1tName(pc_cup, ord(fType^.varargs and strictVararg),
UsualUnaryConversions, fname);
end; {else}
end {if}
else
GenTool(pc_tl1, ftype^.toolNum, long(ftype^.ftype^.size).lsw,
ftype^.dispatcher);
expressionType := ftype^.fType;
lastWasConst := false;
end; {else}
end; {FunctionCall}
procedure CompareCompatible (var t1,t2: typePtr);
{ Make sure that it is legal to compare t1 to t2 }
begin {CompareCompatible}
if (t1^.kind = functionType) or (t2^.kind = functionType) then begin
if not CompTypes(t1, t2) then
Error(47);
end {if}
else if t1^.kind in [pointerType,arrayType] then begin
if t2^.kind in [pointerType,arrayType] then begin
if (t1^.ptype = voidPtr) or (t2^.ptype = voidPtr) then
else if t1^.kind = t2^.kind then begin
if not CompTypes(t1, t2) then
Error(47);
end {if}
else if not CompTypes(t1^.ptype, t2^.ptype) then
Error(47);
t2 := ulongPtr;
end {if}
else if (not lastwasconst) or (lastconst <> 0) then
Error(47);
t1 := ulongPtr;
end {if}
else if expressionType^.kind in [pointerType,arrayType] then begin
if (not tlastwasconst) or (tlastconst <> 0) then
Error(47);
t2 := ulongPtr;
end; {else if}
end; {CompareCompatible}
begin {GenerateCode}
lastwasconst := false;
case tree^.token.kind of
parameterOper:
FunctionCall(tree);
ident: begin
case tree^.id^.itype^.kind of
scalarType: begin
LoadScalar(tree^.id);
expressionType := tree^.id^.itype;
end;
pointerType: begin
LoadScalar(tree^.id);
expressionType := tree^.id^.itype;
end;
arrayType: begin
LoadAddress(tree);
expressionType := expressionType^.ptype;
end;
functionType:
LoadAddress(tree);
structType, unionType: begin
LoadAddress(tree);
if expressionType^.kind = pointerType then
expressionType := expressionType^.ptype;
end;
enumConst: begin
Gen1t(pc_ldc, tree^.id^.itype^.eval, cgWord);
expressionType := wordPtr;
end;
otherwise: ;
end; {case}
end;
intConst,uintConst: begin
Gen1t(pc_ldc, tree^.token.ival, cgWord);
lastwasconst := true;
lastconst := tree^.token.ival;
if tree^.token.kind = intConst then
expressionType := wordPtr
else
expressionType := uwordPtr;
end; {case intConst}
longConst,ulongConst: begin
GenLdcLong(tree^.token.lval);
if tree^.token.kind = longConst then
expressionType := longPtr
else
expressionType := ulongPtr;
lastwasconst := true;
lastconst := tree^.token.lval;
end; {case longConst}
doubleConst: begin
GenLdcReal(tree^.token.rval);
expressionType := doublePtr;
end; {case doubleConst}
stringConst: begin
GenS(pc_lca, tree^.token.sval);
expressionType := stringTypePtr;
end; {case stringConst}
eqch: begin {=}
L_Value(tree^.left);
with tree^.left^ do begin
if token.kind = ident then
kind := id^.itype^.kind
else
kind := definedType;
if kind = arrayType then
if id^.storage = parameter then
kind := pointerType;
if (token.kind = ident)
and (kind in [scalarType,pointerType]) then begin
GenerateCode(tree^.right);
with tree^.left^.id^ do begin
if itype^.kind in [pointerType,arrayType] then
lType := uLongPtr
else
lType := itype;
AssignmentConversion(itype, expressionType, lastWasConst,
lastConst, true, true);
case storage of
stackFrame, parameter:
Gen2t(pc_cop, lln, 0, lType^.baseType);
external, global, private:
Gen1tName(pc_cpo, 0, lType^.baseType, name);
otherwise: ;
end; {case}
end; {with}
end {if}
else begin
LoadAddress(tree^.left);
lType := expressionType;
lisBitField := isBitField;
lbitDisp := bitDisp;
lbitSize := bitSize;
if lType^.kind = arrayType then
lType := lType^.aType
else if lType^.kind = pointerType then
lType := lType^.pType;
GenerateCode(tree^.right);
AssignmentConversion(lType, expressionType, lastWasConst,
lastConst, true, true);
case lType^.kind of
scalarType:
if lisBitField then
Gen2t(pc_cbf, lbitDisp, lbitSize, lType^.baseType)
else
Gen0t(pc_cpi, lType^.baseType);
pointerType:
Gen0t(pc_cpi, cgULong);
structType,unionType:
Gen2(pc_mov, long(lType^.size).msw, long(lType^.size).lsw);
otherwise:
Error(47);
end; {case}
end; {else}
end; {with}
end; {=}
pluseqop, {+=}
minuseqop, {-=}
asteriskeqop, {*=}
slasheqop, {/=}
percenteqop, {%=}
ltlteqop, {<<=}
gtgteqop, {>>=}
andeqop, {&=}
caroteqop, {^=}
bareqop: with tree^.left^ do {|=}
begin
L_Value(tree^.left);
if (token.kind = ident)
and ((id^.itype^.kind in [scalarType,pointerType])
or ((id^.itype^.kind = arrayType) and (id^.storage = parameter))) then begin
doingScalar := true;
LoadScalar(id);
lType := id^.itype;
end {if}
else begin
doingScalar := false;
LoadAddress(tree^.left);
lisBitField := isBitField;
lbitDisp := bitDisp;
lbitSize := bitSize;
t1 := GetTemp(cgLongSize);
Gen2t(pc_str, t1, 0, cgULong);
Gen2t(pc_lod, t1, 0, cgULong);
Gen2t(pc_lod, t1, 0, cgULong);
FreeTemp(t1, cgLongSize);
lType := expressionType^.pType;
if isBitField then begin
if unsigned then
Gen2t(pc_lbu, bitDisp, bitSize, lType^.baseType)
else
Gen2t(pc_lbf, bitDisp, bitSize, lType^.baseType);
end {if}
else if lType^.kind = pointerType then
Gen1t(pc_ind, 0, cgULong)
else
Gen1t(pc_ind, 0, lType^.baseType);
end; {else}
if lType^.isConstant then
Error(93);
if doingScalar
and (ltype^.kind = arrayType) and (id^.storage = parameter) then
kind := pointerType
else
kind := lType^.kind;
GenerateCode(tree^.right);
if kind <> pointerType then
et := UsualBinaryConversions(lType);
case tree^.token.kind of
pluseqop:
if kind = pointerType then begin
ChangePointer(pc_adl, lType^.pType^.size, UsualUnaryConversions);
expressionType := lType;
end
else if et in [cgWord,cgUWord] then
Gen0(pc_adi)
else if et in [cgLong,cgULong] then
Gen0(pc_adl)
else if et = cgExtended then
Gen0(pc_adr)
else
Error(66);
minuseqop:
if kind = pointerType then begin
ChangePointer(pc_sbl, lType^.pType^.size, UsualUnaryConversions);
expressionType := lType;
end
else if et in [cgWord,cgUWord] then
Gen0(pc_sbi)
else if et in [cgLong,cgULong] then
Gen0(pc_sbl)
else if et = cgExtended then
Gen0(pc_sbr)
else
Error(66);
asteriskeqop:
if et = cgWord then
Gen0(pc_mpi)
else if et = cgUWord then
Gen0(pc_umi)
else if et = cgLong then
Gen0(pc_mpl)
else if et = cgULong then
Gen0(pc_uml)
else if et = cgExtended then
Gen0(pc_mpr)
else
Error(66);
slasheqop:
if et = cgWord then
Gen0(pc_dvi)
else if et = cgUWord then
Gen0(pc_udi)
else if et = cgLong then
Gen0(pc_dvl)
else if et = cgULong then
Gen0(pc_udl)
else if et = cgExtended then
Gen0(pc_dvr)
else
Error(66);
percenteqop:
if et = cgWord then
Gen0(pc_mod)
else if et = cgUWord then
Gen0(pc_uim)
else if et = cgLong then
Gen0(pc_mdl)
else if et = cgULong then
Gen0(pc_ulm)
else
Error(66);
ltlteqop:
if et in [cgWord,cgUWord] then
Gen0(pc_shl)
else if et in [cgLong,cgULong] then
Gen0(pc_sll)
else
Error(66);
gtgteqop:
if et = cgWord then
Gen0(pc_shr)
else if et = cgUWord then
Gen0(pc_usr)
else if et = cgLong then
Gen0(pc_slr)
else if et = cgULong then
Gen0(pc_vsr)
else
Error(66);
andeqop:
if et in [cgWord,cgUWord] then
Gen0(pc_bnd)
else if et in [cgLong,cgULong] then
Gen0(pc_bal)
else
Error(66);
caroteqop:
if et in [cgWord,cgUWord] then
Gen0(pc_bxr)
else if et in [cgLong,cgULong] then
Gen0(pc_blx)
else
Error(66);
bareqop:
if et in [cgWord,cgUWord] then
Gen0(pc_bor)
else if et in [cgLong,cgULong] then
Gen0(pc_blr)
else
Error(66);
otherwise: Error(57);
end; {case}
AssignmentConversion(lType,expressionType,false,0,true,true);
if doingScalar then begin
if kind = pointerType then
lType := uLongPtr;
case id^.storage of
stackFrame, parameter:
Gen2t(pc_cop, id^.lln, 0, lType^.baseType);
external, global, private:
Gen1tName(pc_cpo, 0, lType^.baseType, id^.name);
otherwise: ;
end; {case}
end {if}
else begin
if lisBitField then
Gen2t(pc_cbf, lbitDisp, lbitSize, lType^.baseType)
else begin
if ltype^.kind in [pointerType,arrayType] then
lType := uLongPtr;
Gen0t(pc_cpi, lType^.baseType);
end; {else}
Gen0t(pc_bno, lType^.baseType);
end; {else}
end; {with}
commach: begin {,}
GenerateCode(tree^.left);
if expressionType^.baseType <> cgVoid then
Gen0t(pc_pop, UsualUnaryConversions);
GenerateCode(tree^.right);
Gen0t(pc_bno, UsualUnaryConversions);
{result type is already in expressionType}
end; {case commach}
barbarop: begin {||}
GenerateCode(tree^.left);
if expressionType^.kind in [pointerType,arrayType] then
expressionType := uLongPtr
else if UsualUnaryConversions = cgExtended then begin
GenLdcReal(0.0);
Gen0t(pc_neq, cgExtended);
expressionType := wordPtr;
end; {if}
lType := expressionType;
GenerateCode(tree^.right);
if expressionType^.kind in [pointerType,arrayType] then
expressionType := uLongPtr
else if UsualUnaryConversions = cgExtended then begin
GenLdcReal(0.0);
Gen0t(pc_neq, cgExtended);
expressionType := wordPtr;
end; {if}
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_ior);
cgLong,cgULong:
Gen0(pc_lor);
otherwise:
error(66);
end; {case}
expressionType := wordPtr;
end; {case barbarop}
andandop: begin {&&}
GenerateCode(tree^.left);
if expressionType^.kind in [pointerType,arrayType] then
expressionType := uLongPtr
else if UsualUnaryConversions = cgExtended then begin
GenLdcReal(0.0);
Gen0t(pc_neq, cgExtended);
expressionType := wordPtr;
end; {if}
lType := expressionType;
GenerateCode(tree^.right);
if expressionType^.kind in [pointerType,arrayType] then
expressionType := uLongPtr
else if UsualUnaryConversions = cgExtended then begin
GenLdcReal(0.0);
Gen0t(pc_neq, cgExtended);
expressionType := wordPtr;
end; {if}
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_and);
cgLong,cgULong:
Gen0(pc_lnd);
otherwise:
error(66);
end; {case}
expressionType := wordPtr;
end; {case andandop}
carotch: begin {^}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_bxr);
cgLong,cgULong:
Gen0(pc_blx);
otherwise:
error(66);
end; {case}
end; {case carotch}
barch: begin {|}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_bor);
cgLong,cgULong:
Gen0(pc_blr);
otherwise:
error(66);
end; {case}
end; {case barch}
andch: begin {&}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_bnd);
cgLong,cgULong:
Gen0(pc_bal);
otherwise:
error(66);
end; {case}
end; {case andch}
ltltop: begin {<<}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_shl);
cgLong,cgULong:
Gen0(pc_sll);
otherwise:
error(66);
end; {case}
end; {case ltltop}
gtgtop: begin {>>}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgWord:
Gen0(pc_shr);
cgUByte,cgUWord:
Gen0(pc_usr);
cgLong:
Gen0(pc_slr);
cgULong:
Gen0(pc_vsr);
otherwise:
error(66);
end; {case}
end; {case gtgtop}
plusch: begin {+}
if ExpressionKind(tree^.right) in [arrayType,pointerType] then begin
tree^.middle := tree^.right;
tree^.right := tree^.left;
tree^.left := tree^.middle;
end; {if}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
if lType^.kind in [arrayType,pointerType] then begin
{pointer addition}
et := UsualUnaryConversions;
expressionType := lType;
if lType^.kind = arrayType then
lType := lType^.aType
else
lType := lType^.pType;
ChangePointer(pc_adl, lType^.size, et);
end {if}
else begin
{scalar addition}
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_adi);
cgLong,cgULong:
Gen0(pc_adl);
cgExtended:
Gen0(pc_adr);
otherwise:
error(66);
end; {case}
end; {else}
end; {case plusch}
minusch: begin {-}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
if lType^.kind in [pointerType,arrayType] then begin
if lType^.kind = arrayType then
size := lType^.aType^.size
else
size := lType^.pType^.size;
if expressionType^.kind in [arrayType,pointerType] then begin
{subtraction of two pointers}
Gen0(pc_sbl);
if size <> 1 then begin
GenLdcLong(size);
Gen0(pc_dvl);
end; {if}
lType := longPtr;
end {if}
else
{subtract a scalar from a pointer}
ChangePointer(pc_sbl, size, UsualUnaryConversions);
expressionType := lType;
end {if}
else begin
{scalar subtraction}
case UsualBinaryConversions(lType) of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_sbi);
cgLong,cgULong:
Gen0(pc_sbl);
cgExtended:
Gen0(pc_sbr);
otherwise:
error(66);
end; {case}
end; {else}
end; {case minusch}
asteriskch: begin {*}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgWord:
Gen0(pc_mpi);
cgUByte,cgUWord:
Gen0(pc_umi);
cgLong:
Gen0(pc_mpl);
cgULong:
Gen0(pc_uml);
cgExtended:
Gen0(pc_mpr);
otherwise:
error(66);
end; {case}
end; {case asteriskch}
slashch: begin {/}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgWord:
Gen0(pc_dvi);
cgUByte,cgUWord:
Gen0(pc_udi);
cgLong:
Gen0(pc_dvl);
cgULong:
Gen0(pc_udl);
cgExtended:
Gen0(pc_dvr);
otherwise:
error(66);
end; {case}
end; {case slashch}
percentch: begin {%}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
case UsualBinaryConversions(lType) of
cgByte,cgWord:
Gen0(pc_mod);
cgUByte,cgUWord:
Gen0(pc_uim);
cgLong:
Gen0(pc_mdl);
cgULong:
Gen0(pc_ulm);
otherwise:
error(66);
end; {case}
end; {case percentch}
eqeqop, {==}
exceqop: begin {!=}
GenerateCode(tree^.left);
lType := expressionType;
tlastwasconst := lastwasconst;
tlastconst := lastconst;
GenerateCode(tree^.right);
CompareCompatible(ltype, expressionType);
if tree^.token.kind = eqeqop then
Gen0t(pc_equ, UsualBinaryConversions(lType))
else
Gen0t(pc_neq, UsualBinaryConversions(lType));
expressionType := wordPtr;
end; {case exceqop,eqeqop}
lteqop, {<=}
gteqop, {>=}
ltch, {<}
gtch: begin {>}
GenerateCode(tree^.left);
lType := expressionType;
GenerateCode(tree^.right);
CompareCompatible(ltype, expressionType);
if tree^.token.kind = lteqop then
Gen0t(pc_leq, UsualBinaryConversions(lType))
else if tree^.token.kind = gteqop then
Gen0t(pc_geq, UsualBinaryConversions(lType))
else if tree^.token.kind = ltch then
Gen0t(pc_les, UsualBinaryConversions(lType))
else {if tree^.token.kind = gtch then}
Gen0t(pc_grt, UsualBinaryConversions(lType));
expressionType := wordPtr;
end; {case lteqop,gteqop,ltch,gtch}
uminus: begin {unary -}
GenerateCode(tree^.left);
case UsualUnaryConversions of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_ngi);
cgLong,cgULong:
Gen0(pc_ngl);
cgExtended:
Gen0(pc_ngr);
otherwise:
error(66);
end; {case}
end; {case uminus}
tildech: begin {~}
GenerateCode(tree^.left);
case UsualUnaryConversions of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_bnt);
cgLong,cgULong:
Gen0(pc_bnl);
otherwise:
error(66);
end; {case}
end; {case tildech}
excch: begin {!}
GenerateCode(tree^.left);
if expressionType^.kind = pointerType then
expressionType := uLongPtr;
case UsualUnaryConversions of
cgByte,cgUByte,cgWord,cgUWord:
Gen0(pc_not);
cgLong,cgULong: begin
GenLdcLong(0);
Gen0t(pc_equ, cgLong);
end;
cgExtended: begin
GenLdcReal(0.0);
Gen0t(pc_equ, cgExtended);
end;
otherwise:
error(66);
end; {case}
expressionType := wordPtr;
end; {case excch}
plusplusop: {prefix ++}
DoIncDec(tree^.left, pc_lil, pc_gil, pc_iil);
opplusplus: {postfix ++}
DoIncDec(tree^.left, pc_lli, pc_gli, pc_ili);
minusminusop: {prefix --}
DoIncDec(tree^.left, pc_ldl, pc_gdl, pc_idl);
opminusminus: {postfix --}
DoIncDec(tree^.left, pc_lld, pc_gld, pc_ild);
uand: {unary & (address operator)}
LoadAddress(tree^.left);
uasterisk: begin {unary * (indirection)}
GenerateCode(tree^.left);
lType := expressionType;
if lType^.kind in [functiontype,arrayType,pointerType] then begin
if lType^.kind = arrayType then
lType := lType^.aType
else if lType^.kind = pointerType then
lType := lType^.pType;
expressionType := lType;
if lType^.kind = scalarType then
if lType^.baseType = cgVoid then
Gen1t(pc_ind, 0, cgULong)
else
Gen1t(pc_ind, 0, lType^.baseType)
else if lType^.kind = pointerType then
Gen1t(pc_ind, 0, cgULong)
else if not
((lType^.kind in [functionType,arrayType,structType,unionType])
or ((lType^.kind = definedType) and {handle const struct/union}
(lType^.dType^.kind in [structType,unionType]))) then
Error(79);
end {if}
else if not (lType^.kind in [structType,unionType]) then
Error(79);
end; {case uasterisk}
dotch: begin {.}
LoadAddress(tree^.left);
lType := expressionType;
if lType^.kind in [arrayType,pointerType] then begin
if lType^.kind = arrayType then
lType := lType^.aType
else if lType^.kind = pointerType then
lType := lType^.pType;
DoSelection(lType, tree^.right, size);
if (size & $00007FFF) <> size then begin
GenLdcLong(size);
Gen0(pc_adl);
size := 0;
end; {else}
kind := expressionType^.kind;
if kind = scalarType then begin
et := expressionType^.baseType;
if isBitField then begin
GenLdcLong(size);
Gen0(pc_adl);
if unsigned then
Gen2t(pc_lbu, bitDisp, bitSize, et)
else
Gen2t(pc_lbf, bitDisp, bitSize, et);
end {if}
else
Gen1t(pc_ind, long(size).lsw, et);
end {if}
else if kind = pointerType then
Gen1t(pc_ind, long(size).lsw, cgULong)
else if kind = enumType then
Gen1t(pc_ind, long(size).lsw, cgWord)
else if size <> 0 then
Gen1t(pc_inc, long(size).lsw, cgULong);
end {if}
else
Error(79);
end; {case dotch}
colonch: begin {? :}
GenerateCode(tree^.left); {evaluate the condition}
CompareToZero(pc_neq);
GenerateCode(tree^.middle); {evaluate true expression}
lType := expressionType;
tlastwasconst := lastwasconst;
tlastconst := lastconst;
GenerateCode(tree^.right); {evaluate false expression}
isString := false; {handle string operands}
if lType^.kind in [arrayType,pointerType] then
if lType^.aType^.baseType = cgUByte then begin
with expressionType^ do
if kind in [arrayType,pointerType] then begin
if aType^.baseType = cgUByte then
isString := true
else if (kind = pointerType)
and (CompTypes(lType,expressionType)) then
{it's all OK}
else
Error(47)
end {if}
else if (kind = scalarType)
and lastWasConst
and (lastConst = 0) then
et := UsualBinaryConversions(lType)
{it's all OK}
else
Error(47);
lType := voidPtrPtr;
expressionType := voidPtrPtr;
end; {if}
with expressionType^ do
if kind in [arrayType,pointerType] then
if aType^.baseType in [cgByte,cgUByte] then begin
if kind = pointerType then begin
if tlastwasconst and (tlastconst = 0) then
{it's all OK}
else if CompTypes(lType, expressionType) then
{it's all OK}
else
Error(47);
end {if}
else
Error(47);
et := UsualBinaryConversions(lType);
lType := voidPtrPtr;
expressionType := voidPtrPtr;
end; {if}
{generate the operation}
if lType^.kind in [structType, unionType, arrayType] then begin
if not CompTypes(lType, expressionType) then
Error(47);
Gen0(pc_bno);
Gen0t(pc_tri, cgULong);
end {if}
else begin
if expressionType^.kind = pointerType then
tType := expressionType
else
tType := lType;
if (expressionType^.kind = scalarType)
and (expressionType^.baseType = cgVoid)
and (lType^.kind = scalarType)
and (lType^.baseType = cgVoid) then
et := cgVoid
else
et := UsualBinaryConversions(lType);
Gen0(pc_bno);
Gen0t(pc_tri, et);
end; {else}
if isString then {set the type for strings}
expressionType := stringTypePtr;
end; {case colonch}
castoper: begin {(cast)}
GenerateCode(tree^.left);
Cast(tree^.castType);
end; {case castoper}
otherwise:
Error(57);
end; {case}
if doDispose then
dispose(tree);
end; {GenerateCode}
procedure Expression {kind: expressionKind; stopSym: tokenSet};
{ handle an expression }
{ }
{ parameters: }
{ kind - Kind of expression; determines what operations }
{ and what kind of operands are allowed. }
{ stopSym - Set of symbols that can mark the end of an }
{ expression; used to skip tokens after syntax }
{ errors and to block certain operations. For }
{ example, the comma operator is not allowed in }
{ an expression when evaluating a function }
{ parameter list. }
{ }
{ variables: }
{ realExpressionValue - value of a real constant }
{ expression }
{ expressionValue - value of a constant expression }
{ expressionType - type of the constant expression }
label 1;
var
lcodeGeneration: boolean; {local copy of codeGeneration}
ldoDispose: boolean; {local copy of doDispose}
tree: tokenPtr; {expression tree}
castValue: tokenPtr; {element being type cast}
begin {Expression}
errorFound := false; {no error so far}
tree := ExpressionTree(kind, stopSym); {create the expression tree}
if kind = normalExpression then begin {generate code from the expression tree}
if not errorFound then begin
doDispose := true;
GenerateCode(tree);
end; {if}
end {if}
else begin {record the expression for an initializer}
initializerTree := tree;
isConstant := false;
if errorFound then begin
DisposeTree(initializerTree);
initializerTree := nil;
end {if}
else begin
ldoDispose := doDispose; {find the expression type}
doDispose := false;
lcodeGeneration := codeGeneration;
codeGeneration := false;
GenerateCode(tree);
doDispose := ldoDispose;
codeGeneration := lCodeGeneration and (numErrors = 0);
{record the expression}
if tree^.token.kind = castoper then begin
castValue := tree^.left;
while castValue^.token.kind = castoper do
castValue := castValue^.left;
if castValue^.token.kind in [intconst,uintconst] then begin
expressionValue := castValue^.token.ival;
isConstant := true;
expressionType := tree^.castType;
if (castValue^.token.kind = uintconst)
or (expressionType^.kind = pointerType) then
expressionValue := expressionValue & $0000FFFF;
goto 1;
end; {if}
if castValue^.token.kind in [longconst,ulongconst] then begin
expressionValue := castValue^.token.lval;
isConstant := true;
expressionType := tree^.castType;
goto 1;
end; {if}
end; {if}
if tree^.token.kind = intconst then begin
expressionValue := tree^.token.ival;
expressionType := wordPtr;
isConstant := true;
end {else if}
else if tree^.token.kind = uintconst then begin
expressionValue := tree^.token.ival;
expressionValue := expressionValue & $0000FFFF;
expressionType := uwordPtr;
isConstant := true;
end {else if}
else if tree^.token.kind = longconst then begin
expressionValue := tree^.token.lval;
expressionType := longPtr;
isConstant := true;
end {else if}
else if tree^.token.kind = ulongconst then begin
expressionValue := tree^.token.lval;
expressionType := ulongPtr;
isConstant := true;
end {else if}
else if tree^.token.kind = doubleconst then begin
realExpressionValue := tree^.token.rval;
expressionType := extendedPtr;
isConstant := true;
if kind in [arrayExpression,preprocessorExpression] then begin
expressionType := wordPtr;
expressionValue := 1;
Error(47);
end; {if}
end {else if}
else if tree^.token.kind = stringconst then begin
expressionValue := ord4(tree^.token.sval);
expressionType := stringTypePtr;
isConstant := true;
if kind in [arrayExpression,preprocessorExpression] then begin
expressionType := wordPtr;
expressionValue := 1;
Error(47);
end; {if}
end {else if}
else if kind in [arrayExpression,preprocessorExpression] then begin
DisposeTree(initializerTree);
expressionValue := 1;
end; {else if}
end; {else}
end; {else}
1:
end; {Expression}
procedure InitExpression;
{ initialize the expression handler }
begin {InitExpression}
startTerm := [ident,intconst,uintconst,longconst,ulongconst,doubleconst,
stringconst];
startExpression:= startTerm +
[lparench,asteriskch,andch,plusch,minusch,excch,tildech,sizeofsy,
plusplusop,minusminusop,typedef];
end; {InitExpression}
end.
{$append 'expression.asm'}