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cc65/src/cc65/expr.c

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/* expr.c
*
* Ullrich von Bassewitz, 21.06.1998
*/
#include <stdio.h>
#include <stdlib.h>
/* common */
#include "check.h"
#include "debugflag.h"
#include "xmalloc.h"
/* cc65 */
#include "asmcode.h"
#include "asmlabel.h"
#include "asmstmt.h"
#include "assignment.h"
#include "codegen.h"
#include "declare.h"
#include "error.h"
#include "funcdesc.h"
#include "function.h"
#include "global.h"
#include "litpool.h"
#include "macrotab.h"
#include "preproc.h"
#include "scanner.h"
#include "stdfunc.h"
#include "symtab.h"
#include "typecmp.h"
#include "typeconv.h"
#include "expr.h"
/*****************************************************************************/
/* Data */
/*****************************************************************************/
/* Generator attributes */
#define GEN_NOPUSH 0x01 /* Don't push lhs */
/* Map a generator function and its attributes to a token */
typedef struct {
token_t Tok; /* Token to map to */
unsigned Flags; /* Flags for generator function */
void (*Func) (unsigned, unsigned long); /* Generator func */
} GenDesc;
/* Descriptors for the operations */
static GenDesc GenPASGN = { TOK_PLUS_ASSIGN, GEN_NOPUSH, g_add };
static GenDesc GenSASGN = { TOK_MINUS_ASSIGN, GEN_NOPUSH, g_sub };
static GenDesc GenMASGN = { TOK_MUL_ASSIGN, GEN_NOPUSH, g_mul };
static GenDesc GenDASGN = { TOK_DIV_ASSIGN, GEN_NOPUSH, g_div };
static GenDesc GenMOASGN = { TOK_MOD_ASSIGN, GEN_NOPUSH, g_mod };
static GenDesc GenSLASGN = { TOK_SHL_ASSIGN, GEN_NOPUSH, g_asl };
static GenDesc GenSRASGN = { TOK_SHR_ASSIGN, GEN_NOPUSH, g_asr };
static GenDesc GenAASGN = { TOK_AND_ASSIGN, GEN_NOPUSH, g_and };
static GenDesc GenXOASGN = { TOK_XOR_ASSIGN, GEN_NOPUSH, g_xor };
static GenDesc GenOASGN = { TOK_OR_ASSIGN, GEN_NOPUSH, g_or };
/*****************************************************************************/
/* Function forwards */
/*****************************************************************************/
void hie0 (ExprDesc *lval);
/* Parse comma operator. */
void expr (void (*Func) (ExprDesc*), ExprDesc *Expr);
/* Expression parser; func is either hie0 or hie1. */
/*****************************************************************************/
/* Helper functions */
/*****************************************************************************/
static unsigned GlobalModeFlags (unsigned flags)
/* Return the addressing mode flags for the variable with the given flags */
{
flags &= E_MCTYPE;
if (flags == E_TGLAB) {
/* External linkage */
return CF_EXTERNAL;
} else if (flags == E_TREGISTER) {
/* Register variable */
return CF_REGVAR;
} else {
/* Static */
return CF_STATIC;
}
}
static int IsNullPtr (ExprDesc* lval)
/* Return true if this is the NULL pointer constant */
{
return (IsClassInt (lval->Type) && /* Is it an int? */
lval->Flags == E_MCONST && /* Is it constant? */
lval->ConstVal == 0); /* And is it's value zero? */
}
static type* promoteint (type* lhst, type* rhst)
/* In an expression with two ints, return the type of the result */
{
/* Rules for integer types:
* - If one of the values is a long, the result is long.
* - If one of the values is unsigned, the result is also unsigned.
* - Otherwise the result is an int.
*/
if (IsTypeLong (lhst) || IsTypeLong (rhst)) {
if (IsSignUnsigned (lhst) || IsSignUnsigned (rhst)) {
return type_ulong;
} else {
return type_long;
}
} else {
if (IsSignUnsigned (lhst) || IsSignUnsigned (rhst)) {
return type_uint;
} else {
return type_int;
}
}
}
static unsigned typeadjust (ExprDesc* lhs, ExprDesc* rhs, int NoPush)
/* Adjust the two values for a binary operation. lhs is expected on stack or
* to be constant, rhs is expected to be in the primary register or constant.
* The function will put the type of the result into lhs and return the
* code generator flags for the operation.
* If NoPush is given, it is assumed that the operation does not expect the lhs
* to be on stack, and that lhs is in a register instead.
* Beware: The function does only accept int types.
*/
{
unsigned ltype, rtype;
unsigned flags;
/* Get the type strings */
type* lhst = lhs->Type;
type* rhst = rhs->Type;
/* Generate type adjustment code if needed */
ltype = TypeOf (lhst);
if (lhs->Flags == E_MCONST) {
ltype |= CF_CONST;
}
if (NoPush) {
/* Value is in primary register*/
ltype |= CF_REG;
}
rtype = TypeOf (rhst);
if (rhs->Flags == E_MCONST) {
rtype |= CF_CONST;
}
flags = g_typeadjust (ltype, rtype);
/* Set the type of the result */
lhs->Type = promoteint (lhst, rhst);
/* Return the code generator flags */
return flags;
}
void DefineData (ExprDesc* Expr)
/* Output a data definition for the given expression */
{
unsigned Flags = Expr->Flags;
switch (Flags & E_MCTYPE) {
case E_TCONST:
/* Number */
g_defdata (TypeOf (Expr->Type) | CF_CONST, Expr->ConstVal, 0);
break;
case E_TREGISTER:
/* Register variable. Taking the address is usually not
* allowed.
*/
if (IS_Get (&AllowRegVarAddr) == 0) {
Error ("Cannot take the address of a register variable");
}
/* FALLTHROUGH */
case E_TGLAB:
case E_TLLAB:
/* Local or global symbol */
g_defdata (GlobalModeFlags (Flags), Expr->Name, Expr->ConstVal);
break;
case E_TLIT:
/* a literal of some kind */
g_defdata (CF_STATIC, LiteralPoolLabel, Expr->ConstVal);
break;
default:
Internal ("Unknown constant type: %04X", Flags);
}
}
static void LoadConstant (unsigned Flags, ExprDesc* Expr)
/* Load the primary register with some constant value. */
{
switch (Expr->Flags & E_MCTYPE) {
case E_TLOFFS:
g_leasp (Expr->ConstVal);
break;
case E_TCONST:
/* Number constant */
g_getimmed (Flags | TypeOf (Expr->Type) | CF_CONST, Expr->ConstVal, 0);
break;
case E_TREGISTER:
/* Register variable. Taking the address is usually not
* allowed.
*/
if (IS_Get (&AllowRegVarAddr) == 0) {
Error ("Cannot take the address of a register variable");
}
/* FALLTHROUGH */
case E_TGLAB:
case E_TLLAB:
/* Local or global symbol, load address */
Flags |= GlobalModeFlags (Expr->Flags);
Flags &= ~CF_CONST;
g_getimmed (Flags, Expr->Name, Expr->ConstVal);
break;
case E_TLIT:
/* Literal string */
g_getimmed (CF_STATIC, LiteralPoolLabel, Expr->ConstVal);
break;
default:
Internal ("Unknown constant type: %04X", Expr->Flags);
}
}
static int kcalc (token_t tok, long val1, long val2)
/* Calculate an operation with left and right operand constant. */
{
switch (tok) {
case TOK_EQ:
return (val1 == val2);
case TOK_NE:
return (val1 != val2);
case TOK_LT:
return (val1 < val2);
case TOK_LE:
return (val1 <= val2);
case TOK_GE:
return (val1 >= val2);
case TOK_GT:
return (val1 > val2);
case TOK_OR:
return (val1 | val2);
case TOK_XOR:
return (val1 ^ val2);
case TOK_AND:
return (val1 & val2);
case TOK_SHR:
return (val1 >> val2);
case TOK_SHL:
return (val1 << val2);
case TOK_STAR:
return (val1 * val2);
case TOK_DIV:
if (val2 == 0) {
Error ("Division by zero");
return 0x7FFFFFFF;
}
return (val1 / val2);
case TOK_MOD:
if (val2 == 0) {
Error ("Modulo operation with zero");
return 0;
}
return (val1 % val2);
default:
Internal ("kcalc: got token 0x%X\n", tok);
return 0;
}
}
static const GenDesc* FindGen (token_t Tok, const GenDesc* Table)
/* Find a token in a generator table */
{
while (Table->Tok != TOK_INVALID) {
if (Table->Tok == Tok) {
return Table;
}
++Table;
}
return 0;
}
static int TypeSpecAhead (void)
/* Return true if some sort of type is waiting (helper for cast and sizeof()
* in hie10).
*/
{
SymEntry* Entry;
/* There's a type waiting if:
*
* 1. We have an opening paren, and
* a. the next token is a type, or
* b. the next token is a type qualifier, or
* c. the next token is a typedef'd type
*/
return CurTok.Tok == TOK_LPAREN && (
TokIsType (&NextTok) ||
TokIsTypeQual (&NextTok) ||
(NextTok.Tok == TOK_IDENT &&
(Entry = FindSym (NextTok.Ident)) != 0 &&
SymIsTypeDef (Entry)));
}
void PushAddr (ExprDesc* Expr)
/* If the expression contains an address that was somehow evaluated,
* push this address on the stack. This is a helper function for all
* sorts of implicit or explicit assignment functions where the lvalue
* must be saved if it's not constant, before evaluating the rhs.
*/
{
/* Get the address on stack if needed */
if (Expr->Flags != E_MREG && (Expr->Flags & E_MEXPR)) {
/* Push the address (always a pointer) */
g_push (CF_PTR, 0);
}
}
void ConstSubExpr (void (*Func) (ExprDesc*), ExprDesc* Expr)
/* Will evaluate an expression via the given function. If the result is not
* a constant, a diagnostic will be printed, and the value is replaced by
* a constant one to make sure there are no internal errors that result
* from this input error.
*/
{
Func (InitExprDesc (Expr));
if (ED_IsLVal (Expr) != 0 || Expr->Flags != E_MCONST) {
Error ("Constant expression expected");
/* To avoid any compiler errors, make the expression a valid const */
ED_MakeConstInt (Expr, 1);
}
}
void CheckBoolExpr (ExprDesc* Expr)
/* Check if the given expression is a boolean expression, output a diagnostic
* if not.
*/
{
/* If it's an integer, it's ok. If it's not an integer, but a pointer,
* the pointer used in a boolean context is also ok
*/
if (!IsClassInt (Expr->Type) && !IsClassPtr (Expr->Type)) {
Error ("Boolean expression expected");
/* To avoid any compiler errors, make the expression a valid int */
ED_MakeConstInt (Expr, 1);
}
}
/*****************************************************************************/
/* code */
/*****************************************************************************/
void ExprLoad (unsigned Flags, ExprDesc* Expr)
/* Place the result of an expression into the primary register if it is not
* already there.
*/
{
int f;
f = Expr->Flags;
if (ED_IsLVal (Expr)) {
/* Dereferenced lvalue */
Flags |= TypeOf (Expr->Type);
if (Expr->Test & E_FORCETEST) {
Flags |= CF_TEST;
Expr->Test &= ~E_FORCETEST;
}
if (f & E_MGLOBAL) {
/* Reference to a global variable */
Flags |= GlobalModeFlags (f);
g_getstatic (Flags, Expr->Name, Expr->ConstVal);
} else if (f & E_MLOCAL) {
/* Reference to a local variable */
g_getlocal (Flags, Expr->ConstVal);
} else if (f & E_MCONST) {
/* Reference to an absolute address */
g_getstatic (Flags | CF_ABSOLUTE, Expr->ConstVal, 0);
} else if (f == E_MEOFFS) {
/* Reference to address in primary with offset in Expr */
g_getind (Flags, Expr->ConstVal);
} else if (f != E_MREG) {
/* Reference with address in primary */
g_getind (Flags, 0);
} else if (Flags & CF_TEST) {
/* The value is already in the primary but needs a test */
g_test (Flags);
}
} else {
/* An rvalue */
if (f == E_MEOFFS) {
/* reference not storable */
Flags |= TypeOf (Expr->Type);
g_inc (Flags | CF_CONST, Expr->ConstVal);
} else if ((f & E_MEXPR) == 0) {
/* Constant of some sort, load it into the primary */
LoadConstant (Flags, Expr);
}
/* Are we testing this value? */
if (Expr->Test & E_FORCETEST) {
/* Yes, force a test */
Flags |= TypeOf (Expr->Type);
g_test (Flags);
Expr->Test &= ~E_FORCETEST;
}
}
}
static unsigned FunctionParamList (FuncDesc* Func)
/* Parse a function parameter list and pass the parameters to the called
* function. Depending on several criteria this may be done by just pushing
* each parameter separately, or creating the parameter frame once and then
* storing into this frame.
* The function returns the size of the parameters pushed.
*/
{
ExprDesc Expr;
/* Initialize variables */
SymEntry* Param = 0; /* Keep gcc silent */
unsigned ParamSize = 0; /* Size of parameters pushed */
unsigned ParamCount = 0; /* Number of parameters pushed */
unsigned FrameSize = 0; /* Size of parameter frame */
unsigned FrameParams = 0; /* Number of params in frame */
int FrameOffs = 0; /* Offset into parameter frame */
int Ellipsis = 0; /* Function is variadic */
/* As an optimization, we may allocate the complete parameter frame at
* once instead of pushing each parameter as it comes. We may do that,
* if...
*
* - optimizations that increase code size are enabled (allocating the
* stack frame at once gives usually larger code).
* - we have more than one parameter to push (don't count the last param
* for __fastcall__ functions).
*
* The FrameSize variable will contain a value > 0 if storing into a frame
* (instead of pushing) is enabled.
*
*/
if (CodeSizeFactor >= 200) {
/* Calculate the number and size of the parameters */
FrameParams = Func->ParamCount;
FrameSize = Func->ParamSize;
if (FrameParams > 0 && (Func->Flags & FD_FASTCALL) != 0) {
/* Last parameter is not pushed */
FrameSize -= CheckedSizeOf (Func->LastParam->Type);
--FrameParams;
}
/* Do we have more than one parameter in the frame? */
if (FrameParams > 1) {
/* Okeydokey, setup the frame */
FrameOffs = oursp;
g_space (FrameSize);
oursp -= FrameSize;
} else {
/* Don't use a preallocated frame */
FrameSize = 0;
}
}
/* Parse the actual parameter list */
while (CurTok.Tok != TOK_RPAREN) {
unsigned Flags;
/* Count arguments */
++ParamCount;
/* Fetch the pointer to the next argument, check for too many args */
if (ParamCount <= Func->ParamCount) {
/* Beware: If there are parameters with identical names, they
* cannot go into the same symbol table, which means that in this
* case of errorneous input, the number of nodes in the symbol
* table and ParamCount are NOT equal. We have to handle this case
* below to avoid segmentation violations. Since we know that this
* problem can only occur if there is more than one parameter,
* we will just use the last one.
*/
if (ParamCount == 1) {
/* First argument */
Param = Func->SymTab->SymHead;
} else if (Param->NextSym != 0) {
/* Next argument */
Param = Param->NextSym;
CHECK ((Param->Flags & SC_PARAM) != 0);
}
} else if (!Ellipsis) {
/* Too many arguments. Do we have an open param list? */
if ((Func->Flags & FD_VARIADIC) == 0) {
/* End of param list reached, no ellipsis */
Error ("Too many arguments in function call");
}
/* Assume an ellipsis even in case of errors to avoid an error
* message for each other argument.
*/
Ellipsis = 1;
}
/* Evaluate the parameter expression */
hie1 (InitExprDesc (&Expr));
/* If we don't have an argument spec, accept anything, otherwise
* convert the actual argument to the type needed.
*/
Flags = CF_NONE;
if (!Ellipsis) {
/* Convert the argument to the parameter type if needed */
TypeConversion (&Expr, Param->Type);
/* If we have a prototype, chars may be pushed as chars */
Flags |= CF_FORCECHAR;
}
/* Load the value into the primary if it is not already there */
ExprLoad (Flags, &Expr);
/* Use the type of the argument for the push */
Flags |= TypeOf (Expr.Type);
/* If this is a fastcall function, don't push the last argument */
if (ParamCount != Func->ParamCount || (Func->Flags & FD_FASTCALL) == 0) {
unsigned ArgSize = sizeofarg (Flags);
if (FrameSize > 0) {
/* We have the space already allocated, store in the frame.
* Because of invalid type conversions (that have produced an
* error before), we can end up here with a non aligned stack
* frame. Since no output will be generated anyway, handle
* these cases gracefully instead of doing a CHECK.
*/
if (FrameSize >= ArgSize) {
FrameSize -= ArgSize;
} else {
FrameSize = 0;
}
FrameOffs -= ArgSize;
/* Store */
g_putlocal (Flags | CF_NOKEEP, FrameOffs, Expr.ConstVal);
} else {
/* Push the argument */
g_push (Flags, Expr.ConstVal);
}
/* Calculate total parameter size */
ParamSize += ArgSize;
}
/* Check for end of argument list */
if (CurTok.Tok != TOK_COMMA) {
break;
}
NextToken ();
}
/* Check if we had enough parameters */
if (ParamCount < Func->ParamCount) {
Error ("Too few arguments in function call");
}
/* The function returns the size of all parameters pushed onto the stack.
* However, if there are parameters missing (which is an error and was
* flagged by the compiler) AND a stack frame was preallocated above,
* we would loose track of the stackpointer and generate an internal error
* later. So we correct the value by the parameters that should have been
* pushed to avoid an internal compiler error. Since an error was
* generated before, no code will be output anyway.
*/
return ParamSize + FrameSize;
}
static void FunctionCall (ExprDesc* Expr)
/* Perform a function call. */
{
FuncDesc* Func; /* Function descriptor */
int IsFuncPtr; /* Flag */
unsigned ParamSize; /* Number of parameter bytes */
CodeMark Mark = 0; /* Initialize to keep gcc silent */
int PtrOffs = 0; /* Offset of function pointer on stack */
int IsFastCall = 0; /* True if it's a fast call function */
int PtrOnStack = 0; /* True if a pointer copy is on stack */
/* Skip the left paren */
NextToken ();
/* Get a pointer to the function descriptor from the type string */
Func = GetFuncDesc (Expr->Type);
/* Handle function pointers transparently */
IsFuncPtr = IsTypeFuncPtr (Expr->Type);
if (IsFuncPtr) {
/* Check wether it's a fastcall function that has parameters */
IsFastCall = IsFastCallFunc (Expr->Type + 1) && (Func->ParamCount > 0);
/* Things may be difficult, depending on where the function pointer
* resides. If the function pointer is an expression of some sort
* (not a local or global variable), we have to evaluate this
* expression now and save the result for later. Since calls to
* function pointers may be nested, we must save it onto the stack.
* For fastcall functions we do also need to place a copy of the
* pointer on stack, since we cannot use a/x.
*/
PtrOnStack = IsFastCall || ((Expr->Flags & (E_MGLOBAL | E_MLOCAL)) == 0);
if (PtrOnStack) {
/* Not a global or local variable, or a fastcall function. Load
* the pointer into the primary and mark it as an expression.
*/
ExprLoad (CF_NONE, Expr);
Expr->Flags |= E_MEXPR;
/* Remember the code position */
Mark = GetCodePos ();
/* Push the pointer onto the stack and remember the offset */
g_push (CF_PTR, 0);
PtrOffs = oursp;
}
/* Check for known standard functions and inline them if requested */
} else if (IS_Get (&InlineStdFuncs) && IsStdFunc ((const char*) Expr->Name)) {
/* Inline this function */
HandleStdFunc (Func, Expr);
return;
}
/* Parse the parameter list */
ParamSize = FunctionParamList (Func);
/* We need the closing paren here */
ConsumeRParen ();
/* Special handling for function pointers */
if (IsFuncPtr) {
/* If the function is not a fastcall function, load the pointer to
* the function into the primary.
*/
if (!IsFastCall) {
/* Not a fastcall function - we may use the primary */
if (PtrOnStack) {
/* If we have no parameters, the pointer is still in the
* primary. Remove the code to push it and correct the
* stack pointer.
*/
if (ParamSize == 0) {
RemoveCode (Mark);
pop (CF_PTR);
PtrOnStack = 0;
} else {
/* Load from the saved copy */
g_getlocal (CF_PTR, PtrOffs);
}
} else {
/* Load from original location */
ExprLoad (CF_NONE, Expr);
}
/* Call the function */
g_callind (TypeOf (Expr->Type+1), ParamSize, PtrOffs);
} else {
/* Fastcall function. We cannot use the primary for the function
* pointer and must therefore use an offset to the stack location.
* Since fastcall functions may never be variadic, we can use the
* index register for this purpose.
*/
g_callind (CF_LOCAL, ParamSize, PtrOffs);
}
/* If we have a pointer on stack, remove it */
if (PtrOnStack) {
g_space (- (int) sizeofarg (CF_PTR));
pop (CF_PTR);
}
/* Skip T_PTR */
++Expr->Type;
} else {
/* Normal function */
g_call (TypeOf (Expr->Type), (const char*) Expr->Name, ParamSize);
}
}
static void Primary (ExprDesc* E)
/* This is the lowest level of the expression parser. */
{
SymEntry* Sym;
/* Initialize fields in the expression stucture */
E->Test = 0; /* No test */
E->Sym = 0; /* Symbol unknown */
/* Character and integer constants. */
if (CurTok.Tok == TOK_ICONST || CurTok.Tok == TOK_CCONST) {
E->Flags = E_MCONST | E_TCONST | E_RVAL;
E->Type = CurTok.Type;
E->ConstVal = CurTok.IVal;
NextToken ();
return;
}
/* Process parenthesized subexpression by calling the whole parser
* recursively.
*/
if (CurTok.Tok == TOK_LPAREN) {
NextToken ();
hie0 (InitExprDesc (E));
ConsumeRParen ();
return;
}
/* If we run into an identifier in preprocessing mode, we assume that this
* is an undefined macro and replace it by a constant value of zero.
*/
if (Preprocessing && CurTok.Tok == TOK_IDENT) {
ED_MakeConstInt (E, 0);
return;
}
/* All others may only be used if the expression evaluation is not called
* recursively by the preprocessor.
*/
if (Preprocessing) {
/* Illegal expression in PP mode */
Error ("Preprocessor expression expected");
ED_MakeConstInt (E, 1);
return;
}
switch (CurTok.Tok) {
case TOK_IDENT:
/* Identifier. Get a pointer to the symbol table entry */
Sym = E->Sym = FindSym (CurTok.Ident);
/* Is the symbol known? */
if (Sym) {
/* We found the symbol - skip the name token */
NextToken ();
/* The expression type is the symbol type */
E->Type = Sym->Type;
/* Check for illegal symbol types */
CHECK ((Sym->Flags & SC_LABEL) != SC_LABEL);
if (Sym->Flags & SC_TYPE) {
/* Cannot use type symbols */
Error ("Variable identifier expected");
/* Assume an int type to make E valid */
E->Flags = E_MLOCAL | E_TLOFFS | E_LVAL;
E->Type = type_int;
E->ConstVal = 0;
return;
}
/* Mark the symbol as referenced */
Sym->Flags |= SC_REF;
/* Check for legal symbol types */
if ((Sym->Flags & SC_CONST) == SC_CONST) {
/* Enum or some other numeric constant */
E->Flags = E_MCONST | E_TCONST | E_RVAL;
E->ConstVal = Sym->V.ConstVal;
} else if ((Sym->Flags & SC_FUNC) == SC_FUNC) {
/* Function */
E->Flags = E_MGLOBAL | E_MCONST | E_TGLAB | E_RVAL;
E->Name = (unsigned long) Sym->Name;
E->ConstVal = 0;
} else if ((Sym->Flags & SC_AUTO) == SC_AUTO) {
/* Local variable. If this is a parameter for a variadic
* function, we have to add some address calculations, and the
* address is not const.
*/
if ((Sym->Flags & SC_PARAM) == SC_PARAM && F_IsVariadic (CurrentFunc)) {
/* Variadic parameter */
g_leavariadic (Sym->V.Offs - F_GetParamSize (CurrentFunc));
E->Flags = E_MEXPR | E_LVAL;
E->ConstVal = 0;
} else {
/* Normal parameter */
E->Flags = E_MLOCAL | E_TLOFFS | E_LVAL;
E->ConstVal = Sym->V.Offs;
}
} else if ((Sym->Flags & SC_REGISTER) == SC_REGISTER) {
/* Register variable, zero page based */
E->Flags = E_MGLOBAL | E_MCONST | E_TREGISTER | E_LVAL;
E->Name = Sym->V.R.RegOffs;
E->ConstVal = 0;
} else if ((Sym->Flags & SC_STATIC) == SC_STATIC) {
/* Static variable */
if (Sym->Flags & (SC_EXTERN | SC_STORAGE)) {
E->Flags = E_MGLOBAL | E_MCONST | E_TGLAB | E_LVAL;
E->Name = (unsigned long) Sym->Name;
} else {
E->Flags = E_MGLOBAL | E_MCONST | E_TLLAB | E_LVAL;
E->Name = Sym->V.Label;
}
E->ConstVal = 0;
} else {
/* Local static variable */
E->Flags = E_MGLOBAL | E_MCONST | E_TLLAB | E_LVAL;
E->Name = Sym->V.Offs;
E->ConstVal = 0;
}
/* The following should not be necessary if the reference flag is
* set right above, but currently I do not oversee if it's really
* needed and the old code did it.
* ###
*/
ED_SetValType (E, !IsTypeFunc (E->Type) && !IsTypeArray (E->Type));
} else {
/* We did not find the symbol. Remember the name, then skip it */
ident Ident;
strcpy (Ident, CurTok.Ident);
NextToken ();
/* IDENT is either an auto-declared function or an undefined variable. */
if (CurTok.Tok == TOK_LPAREN) {
/* Declare a function returning int. For that purpose, prepare a
* function signature for a function having an empty param list
* and returning int.
*/
Warning ("Function call without a prototype");
Sym = AddGlobalSym (Ident, GetImplicitFuncType(), SC_EXTERN | SC_REF | SC_FUNC);
E->Type = Sym->Type;
E->Flags = E_MGLOBAL | E_MCONST | E_TGLAB | E_RVAL;
E->Name = (unsigned long) Sym->Name;
E->ConstVal = 0;
} else {
/* Undeclared Variable */
Sym = AddLocalSym (Ident, type_int, SC_AUTO | SC_REF, 0);
E->Flags = E_MLOCAL | E_TLOFFS | E_LVAL;
E->Type = type_int;
E->ConstVal = 0;
Error ("Undefined symbol: `%s'", Ident);
}
}
break;
case TOK_SCONST:
/* String literal */
E->Flags = E_MCONST | E_TLIT | E_RVAL;
E->ConstVal = CurTok.IVal;
E->Type = GetCharArrayType (GetLiteralPoolOffs () - CurTok.IVal);
NextToken ();
break;
case TOK_ASM:
/* ASM statement */
AsmStatement ();
E->Flags = E_MEXPR | E_RVAL;
E->ConstVal = 0;
E->Type = type_void;
break;
case TOK_AX:
case TOK_EAX:
/* __AX__ and __EAX__ pseudo values */
E->Type = (CurTok.Tok == TOK_AX)? type_uint : type_ulong;
E->Flags = E_MREG | E_LVAL; /* May be used as lvalue */
E->Test &= ~E_CC;
E->ConstVal = 0;
NextToken ();
break;
default:
/* Illegal primary. */
Error ("Expression expected");
ED_MakeConstInt (E, 1);
break;
}
}
static void ArrayRef (ExprDesc* Expr)
/* Handle an array reference */
{
unsigned lflags;
unsigned rflags;
int ConstBaseAddr;
int ConstSubAddr;
ExprDesc lval2;
CodeMark Mark1;
CodeMark Mark2;
type* tptr1;
type* tptr2;
/* Skip the bracket */
NextToken ();
/* Get the type of left side */
tptr1 = Expr->Type;
/* We can apply a special treatment for arrays that have a const base
* address. This is true for most arrays and will produce a lot better
* code. Check if this is a const base address.
*/
lflags = Expr->Flags & ~E_MCTYPE;
ConstBaseAddr = (lflags == E_MCONST) || /* Constant numeric address */
(lflags & E_MGLOBAL) != 0 || /* Static array, or ... */
lflags == E_MLOCAL; /* Local array */
/* If we have a constant base, we delay the address fetch */
Mark1 = GetCodePos ();
Mark2 = 0; /* Silence gcc */
if (!ConstBaseAddr) {
/* Get a pointer to the array into the primary */
ExprLoad (CF_NONE, Expr);
/* Get the array pointer on stack. Do not push more than 16
* bit, even if this value is greater, since we cannot handle
* other than 16bit stuff when doing indexing.
*/
Mark2 = GetCodePos ();
g_push (CF_PTR, 0);
}
/* TOS now contains ptr to array elements. Get the subscript. */
hie0 (&lval2);
if (ED_IsRVal (&lval2) && lval2.Flags == E_MCONST) {
/* The array subscript is a constant - remove value from stack */
if (!ConstBaseAddr) {
RemoveCode (Mark2);
pop (CF_PTR);
} else {
/* Get an array pointer into the primary */
ExprLoad (CF_NONE, Expr);
}
if (IsClassPtr (tptr1)) {
/* Scale the subscript value according to element size */
lval2.ConstVal *= CheckedPSizeOf (tptr1);
/* Remove code for lhs load */
RemoveCode (Mark1);
/* Handle constant base array on stack. Be sure NOT to
* handle pointers the same way, and check for character literals
* (both won't work).
*/
if (IsTypeArray (tptr1) && Expr->Flags != (E_MCONST | E_TLIT) &&
((Expr->Flags & ~E_MCTYPE) == E_MCONST ||
(Expr->Flags & ~E_MCTYPE) == E_MLOCAL ||
(Expr->Flags & E_MGLOBAL) != 0 ||
(Expr->Flags == E_MEOFFS))) {
Expr->ConstVal += lval2.ConstVal;
} else {
/* Pointer - load into primary and remember offset */
if ((Expr->Flags & E_MEXPR) == 0 || ED_IsLVal (Expr)) {
ExprLoad (CF_NONE, Expr);
}
Expr->ConstVal = lval2.ConstVal;
Expr->Flags = E_MEOFFS;
}
/* Result is of element type */
Expr->Type = Indirect (tptr1);
/* Done */
goto end_array;
} else if (IsClassPtr (tptr2 = lval2.Type)) {
/* Subscript is pointer, get element type */
lval2.Type = Indirect (tptr2);
/* Scale the rhs value in the primary register */
g_scale (TypeOf (tptr1), CheckedSizeOf (lval2.Type));
/* */
Expr->Type = lval2.Type;
} else {
Error ("Cannot subscript");
}
/* Add the subscript. Since arrays are indexed by integers,
* we will ignore the true type of the subscript here and
* use always an int.
*/
g_inc (CF_INT | CF_CONST, lval2.ConstVal);
} else {
/* Array subscript is not constant. Load it into the primary */
Mark2 = GetCodePos ();
ExprLoad (CF_NONE, &lval2);
tptr2 = lval2.Type;
if (IsClassPtr (tptr1)) {
/* Get the element type */
Expr->Type = Indirect (tptr1);
/* Indexing is based on int's, so we will just use the integer
* portion of the index (which is in (e)ax, so there's no further
* action required).
*/
g_scale (CF_INT, CheckedSizeOf (Expr->Type));
} else if (IsClassPtr (tptr2)) {
/* Get the element type */
lval2.Type = Indirect (tptr2);
/* Get the int value on top. If we go here, we're sure,
* both values are 16 bit (the first one was truncated
* if necessary and the second one is a pointer).
* Note: If ConstBaseAddr is true, we don't have a value on
* stack, so to "swap" both, just push the subscript.
*/
if (ConstBaseAddr) {
g_push (CF_INT, 0);
ExprLoad (CF_NONE, Expr);
ConstBaseAddr = 0;
} else {
g_swap (CF_INT);
}
/* Scale it */
g_scale (TypeOf (tptr1), CheckedSizeOf (lval2.Type));
Expr->Type = lval2.Type;
} else {
Error ("Cannot subscript");
}
/* The offset is now in the primary register. It didn't have a
* constant base address for the lhs, the lhs address is already
* on stack, and we must add the offset. If the base address was
* constant, we call special functions to add the address to the
* offset value.
*/
if (!ConstBaseAddr) {
/* Add the subscript. Both values are int sized. */
g_add (CF_INT, 0);
} else {
/* If the subscript has itself a constant address, it is often
* a better idea to reverse again the order of the evaluation.
* This will generate better code if the subscript is a byte
* sized variable. But beware: This is only possible if the
* subscript was not scaled, that is, if this was a byte array
* or pointer.
*/
rflags = lval2.Flags & ~E_MCTYPE;
ConstSubAddr = (rflags == E_MCONST) || /* Constant numeric address */
(rflags & E_MGLOBAL) != 0 || /* Static array, or ... */
rflags == E_MLOCAL; /* Local array */
if (ConstSubAddr && CheckedSizeOf (Expr->Type) == SIZEOF_CHAR) {
type* SavedType;
/* Reverse the order of evaluation */
unsigned flags = (CheckedSizeOf (lval2.Type) == SIZEOF_CHAR)? CF_CHAR : CF_INT;
RemoveCode (Mark2);
/* Get a pointer to the array into the primary. We have changed
* Type above but we need the original type to load the
* address, so restore it temporarily.
*/
SavedType = Expr->Type;
Expr->Type = tptr1;
ExprLoad (CF_NONE, Expr);
Expr->Type = SavedType;
/* Add the variable */
if (rflags == E_MLOCAL) {
g_addlocal (flags, lval2.ConstVal);
} else {
flags |= GlobalModeFlags (lval2.Flags);
g_addstatic (flags, lval2.Name, lval2.ConstVal);
}
} else {
if (lflags == E_MCONST) {
/* Constant numeric address. Just add it */
g_inc (CF_INT | CF_UNSIGNED, Expr->ConstVal);
} else if (lflags == E_MLOCAL) {
/* Base address is a local variable address */
if (IsTypeArray (tptr1)) {
g_addaddr_local (CF_INT, Expr->ConstVal);
} else {
g_addlocal (CF_PTR, Expr->ConstVal);
}
} else {
/* Base address is a static variable address */
unsigned flags = CF_INT;
flags |= GlobalModeFlags (Expr->Flags);
if (IsTypeArray (tptr1)) {
g_addaddr_static (flags, Expr->Name, Expr->ConstVal);
} else {
g_addstatic (flags, Expr->Name, Expr->ConstVal);
}
}
}
}
}
Expr->Flags = E_MEXPR;
end_array:
ConsumeRBrack ();
ED_SetValType (Expr, !IsTypeArray (Expr->Type));
}
static void StructRef (ExprDesc* Expr)
/* Process struct field after . or ->. */
{
ident Ident;
SymEntry* Field;
int Flags;
/* Skip the token and check for an identifier */
NextToken ();
if (CurTok.Tok != TOK_IDENT) {
Error ("Identifier expected");
Expr->Type = type_int;
return;
}
/* Get the symbol table entry and check for a struct field */
strcpy (Ident, CurTok.Ident);
NextToken ();
Field = FindStructField (Expr->Type, Ident);
if (Field == 0) {
Error ("Struct/union has no field named `%s'", Ident);
Expr->Type = type_int;
return;
}
/* If we have constant input data, the result is also constant */
Flags = (Expr->Flags & ~E_MCTYPE);
if (Flags == E_MCONST ||
(ED_IsRVal (Expr) && (Flags == E_MLOCAL ||
(Flags & E_MGLOBAL) != 0 ||
Expr->Flags == E_MEOFFS))) {
Expr->ConstVal += Field->V.Offs;
} else {
if ((Flags & E_MEXPR) == 0 || ED_IsLVal (Expr)) {
ExprLoad (CF_NONE, Expr);
}
Expr->ConstVal = Field->V.Offs;
Expr->Flags = E_MEOFFS;
}
Expr->Type = Field->Type;
ED_SetValType (Expr, !IsTypeArray (Field->Type));
}
static void hie11 (ExprDesc *Expr)
/* Handle compound types (structs and arrays) */
{
/* Evaluate the lhs */
Primary (Expr);
/* Check for a rhs */
while (CurTok.Tok == TOK_LBRACK || CurTok.Tok == TOK_LPAREN ||
CurTok.Tok == TOK_DOT || CurTok.Tok == TOK_PTR_REF) {
switch (CurTok.Tok) {
case TOK_LBRACK:
/* Array reference */
ArrayRef (Expr);
break;
case TOK_LPAREN:
/* Function call. */
if (IsTypeFunc (Expr->Type) || IsTypeFuncPtr (Expr->Type)) {
/* Call the function */
FunctionCall (Expr);
/* Result is in the primary register */
Expr->Flags = E_MEXPR | E_RVAL;
/* Set to result */
Expr->Type = GetFuncReturn (Expr->Type);
} else {
Error ("Illegal function call");
ED_MakeRVal (Expr);
}
break;
case TOK_DOT:
if (!IsClassStruct (Expr->Type)) {
Error ("Struct expected");
}
ED_MakeRVal (Expr); /* #### ? */
StructRef (Expr);
break;
case TOK_PTR_REF:
/* If we have an array, convert it to pointer to first element */
if (IsTypeArray (Expr->Type)) {
Expr->Type = ArrayToPtr (Expr->Type);
}
if (!IsClassPtr (Expr->Type) || !IsClassStruct (Indirect (Expr->Type))) {
Error ("Struct pointer expected");
}
StructRef (Expr);
break;
default:
Internal ("Invalid token in hie11: %d", CurTok.Tok);
}
}
}
void Store (ExprDesc* Expr, const type* StoreType)
/* Store the primary register into the location denoted by Expr. If StoreType
* is given, use this type when storing instead of Expr->Type. If StoreType
* is NULL, use Expr->Type instead.
*/
{
unsigned Flags;
unsigned f = Expr->Flags;
/* If StoreType was not given, use Expr->Type instead */
if (StoreType == 0) {
StoreType = Expr->Type;
}
/* Get the code generator flags */
Flags = TypeOf (StoreType);
if (f & E_MGLOBAL) {
Flags |= GlobalModeFlags (f);
if (Expr->Test) {
/* Just testing */
Flags |= CF_TEST;
}
/* Generate code */
g_putstatic (Flags, Expr->Name, Expr->ConstVal);
} else if (f & E_MLOCAL) {
/* Store an auto variable */
g_putlocal (Flags, Expr->ConstVal, 0);
} else if (f == E_MEOFFS) {
/* Store indirect with offset */
g_putind (Flags, Expr->ConstVal);
} else if (f != E_MREG) {
if (f & E_MEXPR) {
/* Indirect without offset */
g_putind (Flags, 0);
} else {
/* Store into absolute address */
g_putstatic (Flags | CF_ABSOLUTE, Expr->ConstVal, 0);
}
}
/* Assume that each one of the stores will invalidate CC */
Expr->Test &= ~E_CC;
}
static void PreIncDec (ExprDesc* Expr, void (*inc) (unsigned, unsigned long))
/* Handle --i and ++i */
{
unsigned flags;
unsigned long val;
/* Skip the operator token */
NextToken ();
/* Evaluate the expression and check that it is an lvalue */
hie10 (Expr);
if (ED_IsRVal (Expr) == 0) {
Error ("Invalid lvalue");
return;
}
/* Get the data type */
flags = TypeOf (Expr->Type) | CF_FORCECHAR | CF_CONST;
/* Get the increment value in bytes */
val = (Expr->Type[0] == T_PTR)? CheckedPSizeOf (Expr->Type) : 1;
/* Check for special addressing modes */
if (Expr->Flags & E_MGLOBAL) {
/* Global address */
flags |= GlobalModeFlags (Expr->Flags);
if (inc == g_inc) {
g_addeqstatic (flags, Expr->Name, Expr->ConstVal, val);
} else {
g_subeqstatic (flags, Expr->Name, Expr->ConstVal, val);
}
} else if (Expr->Flags & E_MLOCAL) {
/* Local address */
if (inc == g_inc) {
g_addeqlocal (flags, Expr->ConstVal, val);
} else {
g_subeqlocal (flags, Expr->ConstVal, val);
}
} else if (Expr->Flags & E_MCONST) {
/* Constant absolute address */
flags |= CF_ABSOLUTE;
if (inc == g_inc) {
g_addeqstatic (flags, Expr->ConstVal, 0, val);
} else {
g_subeqstatic (flags, Expr->ConstVal, 0, val);
}
} else if (Expr->Flags & E_MEXPR) {
/* Address in a/x, check if we have an offset */
unsigned Offs = (Expr->Flags == E_MEOFFS)? Expr->ConstVal : 0;
if (inc == g_inc) {
g_addeqind (flags, Offs, val);
} else {
g_subeqind (flags, Offs, val);
}
} else {
/* Use generic code. Push the address if needed */
PushAddr (Expr);
/* Fetch the value */
ExprLoad (CF_NONE, Expr);
/* Increment value in primary */
inc (flags, val);
/* Store the result back */
Store (Expr, 0);
}
/* Result is an expression, no reference */
Expr->Flags = E_MEXPR | E_RVAL;
}
static void PostIncDec (ExprDesc* Expr, void (*inc) (unsigned, unsigned long))
/* Handle i-- and i++ */
{
unsigned flags;
NextToken ();
/* The expression to increment must be an lvalue */
if (ED_IsRVal (Expr)) {
Error ("Invalid lvalue");
return;
}
/* Get the data type */
flags = TypeOf (Expr->Type);
/* Push the address if needed */
PushAddr (Expr);
/* Fetch the value and save it (since it's the result of the expression) */
ExprLoad (CF_NONE, Expr);
g_save (flags | CF_FORCECHAR);
/* If we have a pointer expression, increment by the size of the type */
if (Expr->Type[0] == T_PTR) {
inc (flags | CF_CONST | CF_FORCECHAR, CheckedSizeOf (Expr->Type + 1));
} else {
inc (flags | CF_CONST | CF_FORCECHAR, 1);
}
/* Store the result back */
Store (Expr, 0);
/* Restore the original value in the primary register */
g_restore (flags | CF_FORCECHAR);
/* The result is always an expression, no reference */
Expr->Flags = E_MEXPR | E_RVAL;
}
static void UnaryOp (ExprDesc* Expr)
/* Handle unary -/+ and ~ */
{
unsigned flags;
/* Remember the operator token and skip it */
token_t Tok = CurTok.Tok;
NextToken ();
/* Get the expression */
hie10 (Expr);
/* Check for a constant expression */
if (ED_IsRVal (Expr) && (Expr->Flags & E_MCONST) != 0) {
/* Value is constant */
switch (Tok) {
case TOK_MINUS: Expr->ConstVal = -Expr->ConstVal; break;
case TOK_PLUS: break;
case TOK_COMP: Expr->ConstVal = ~Expr->ConstVal; break;
default: Internal ("Unexpected token: %d", Tok);
}
} else {
/* Value is not constant */
ExprLoad (CF_NONE, Expr);
/* Get the type of the expression */
flags = TypeOf (Expr->Type);
/* Handle the operation */
switch (Tok) {
case TOK_MINUS: g_neg (flags); break;
case TOK_PLUS: break;
case TOK_COMP: g_com (flags); break;
default: Internal ("Unexpected token: %d", Tok);
}
/* The result is a rvalue in the primary */
Expr->Flags = E_MEXPR | E_RVAL;
}
}
void hie10 (ExprDesc* Expr)
/* Handle ++, --, !, unary - etc. */
{
switch (CurTok.Tok) {
case TOK_INC:
PreIncDec (Expr, g_inc);
break;
case TOK_DEC:
PostIncDec (Expr, g_dec);
break;
case TOK_PLUS:
case TOK_MINUS:
case TOK_COMP:
UnaryOp (Expr);
break;
case TOK_BOOL_NOT:
NextToken ();
if (evalexpr (CF_NONE, hie10, Expr) == 0) {
/* Constant expression */
Expr->ConstVal = !Expr->ConstVal;
} else {
g_bneg (TypeOf (Expr->Type));
Expr->Test |= E_CC; /* bneg will set cc */
Expr->Flags = E_MEXPR | E_RVAL; /* say it's an expr */
}
break;
case TOK_STAR:
NextToken ();
if (evalexpr (CF_NONE, hie10, Expr) != 0) {
/* Expression is not const, indirect value loaded into primary */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->ConstVal = 0; /* Offset is zero now */
}
/* If the expression is already a pointer to function, the
* additional dereferencing operator must be ignored.
*/
if (IsTypeFuncPtr (Expr->Type)) {
/* Expression not storable */
ED_MakeRVal (Expr);
} else {
if (IsClassPtr (Expr->Type)) {
Expr->Type = Indirect (Expr->Type);
} else {
Error ("Illegal indirection");
}
ED_MakeLVal (Expr);
}
break;
case TOK_AND:
NextToken ();
hie10 (Expr);
/* The & operator may be applied to any lvalue, and it may be
* applied to functions, even if they're no lvalues.
*/
if (ED_IsRVal (Expr) && !IsTypeFunc (Expr->Type)) {
/* Allow the & operator with an array */
if (!IsTypeArray (Expr->Type)) {
Error ("Illegal address");
}
} else {
Expr->Type = PointerTo (Expr->Type);
ED_MakeRVal (Expr);
}
break;
case TOK_SIZEOF:
NextToken ();
if (TypeSpecAhead ()) {
type Type[MAXTYPELEN];
NextToken ();
Expr->ConstVal = CheckedSizeOf (ParseType (Type));
ConsumeRParen ();
} else {
/* Remember the output queue pointer */
CodeMark Mark = GetCodePos ();
hie10 (Expr);
Expr->ConstVal = CheckedSizeOf (Expr->Type);
/* Remove any generated code */
RemoveCode (Mark);
}
Expr->Flags = E_MCONST | E_TCONST | E_RVAL;
Expr->Type = type_size_t;
Expr->Test &= ~E_CC;
break;
default:
if (TypeSpecAhead ()) {
/* A typecast */
TypeCast (Expr);
} else {
/* An expression */
hie11 (Expr);
/* Handle post increment */
if (CurTok.Tok == TOK_INC) {
PostIncDec (Expr, g_inc);
} else if (CurTok.Tok == TOK_DEC) {
PostIncDec (Expr, g_dec);
}
}
break;
}
}
static void hie_internal (const GenDesc* Ops, /* List of generators */
ExprDesc* Expr,
void (*hienext) (ExprDesc*),
int* UsedGen)
/* Helper function */
{
ExprDesc lval2;
CodeMark Mark1;
CodeMark Mark2;
const GenDesc* Gen;
token_t Tok; /* The operator token */
unsigned ltype, type;
int rconst; /* Operand is a constant */
hienext (Expr);
*UsedGen = 0;
while ((Gen = FindGen (CurTok.Tok, Ops)) != 0) {
/* Tell the caller that we handled it's ops */
*UsedGen = 1;
/* All operators that call this function expect an int on the lhs */
if (!IsClassInt (Expr->Type)) {
Error ("Integer expression expected");
}
/* Remember the operator token, then skip it */
Tok = CurTok.Tok;
NextToken ();
/* Get the lhs on stack */
Mark1 = GetCodePos ();
ltype = TypeOf (Expr->Type);
if (ED_IsRVal (Expr) && Expr->Flags == E_MCONST) {
/* Constant value */
Mark2 = GetCodePos ();
g_push (ltype | CF_CONST, Expr->ConstVal);
} else {
/* Value not constant */
ExprLoad (CF_NONE, Expr);
Mark2 = GetCodePos ();
g_push (ltype, 0);
}
/* Get the right hand side */
rconst = (evalexpr (CF_NONE, hienext, &lval2) == 0);
/* Check the type of the rhs */
if (!IsClassInt (lval2.Type)) {
Error ("Integer expression expected");
}
/* Check for const operands */
if (ED_IsRVal (Expr) && Expr->Flags == E_MCONST && rconst) {
/* Both operands are constant, remove the generated code */
RemoveCode (Mark1);
pop (ltype);
/* Evaluate the result */
Expr->ConstVal = kcalc (Tok, Expr->ConstVal, lval2.ConstVal);
/* Get the type of the result */
Expr->Type = promoteint (Expr->Type, lval2.Type);
} else {
/* If the right hand side is constant, and the generator function
* expects the lhs in the primary, remove the push of the primary
* now.
*/
unsigned rtype = TypeOf (lval2.Type);
type = 0;
if (rconst) {
/* Second value is constant - check for div */
type |= CF_CONST;
rtype |= CF_CONST;
if (Tok == TOK_DIV && lval2.ConstVal == 0) {
Error ("Division by zero");
} else if (Tok == TOK_MOD && lval2.ConstVal == 0) {
Error ("Modulo operation with zero");
}
if ((Gen->Flags & GEN_NOPUSH) != 0) {
RemoveCode (Mark2);
pop (ltype);
ltype |= CF_REG; /* Value is in register */
}
}
/* Determine the type of the operation result. */
type |= g_typeadjust (ltype, rtype);
Expr->Type = promoteint (Expr->Type, lval2.Type);
/* Generate code */
Gen->Func (type, lval2.ConstVal);
/* We have a rvalue in the primary now */
Expr->Flags = E_MEXPR | E_RVAL;
}
}
}
static void hie_compare (const GenDesc* Ops, /* List of generators */
ExprDesc* Expr,
void (*hienext) (ExprDesc*))
/* Helper function for the compare operators */
{
ExprDesc lval2;
CodeMark Mark1;
CodeMark Mark2;
const GenDesc* Gen;
token_t tok; /* The operator token */
unsigned ltype;
int rconst; /* Operand is a constant */
hienext (Expr);
while ((Gen = FindGen (CurTok.Tok, Ops)) != 0) {
/* Remember the operator token, then skip it */
tok = CurTok.Tok;
NextToken ();
/* Get the lhs on stack */
Mark1 = GetCodePos ();
ltype = TypeOf (Expr->Type);
if (ED_IsRVal (Expr) && Expr->Flags == E_MCONST) {
/* Constant value */
Mark2 = GetCodePos ();
g_push (ltype | CF_CONST, Expr->ConstVal);
} else {
/* Value not constant */
ExprLoad (CF_NONE, Expr);
Mark2 = GetCodePos ();
g_push (ltype, 0);
}
/* Get the right hand side */
rconst = (evalexpr (CF_NONE, hienext, &lval2) == 0);
/* Make sure, the types are compatible */
if (IsClassInt (Expr->Type)) {
if (!IsClassInt (lval2.Type) && !(IsClassPtr(lval2.Type) && IsNullPtr(Expr))) {
Error ("Incompatible types");
}
} else if (IsClassPtr (Expr->Type)) {
if (IsClassPtr (lval2.Type)) {
/* Both pointers are allowed in comparison if they point to
* the same type, or if one of them is a void pointer.
*/
type* left = Indirect (Expr->Type);
type* right = Indirect (lval2.Type);
if (TypeCmp (left, right) < TC_EQUAL && *left != T_VOID && *right != T_VOID) {
/* Incomatible pointers */
Error ("Incompatible types");
}
} else if (!IsNullPtr (&lval2)) {
Error ("Incompatible types");
}
}
/* Check for const operands */
if (ED_IsRVal (Expr) && Expr->Flags == E_MCONST && rconst) {
/* Both operands are constant, remove the generated code */
RemoveCode (Mark1);
pop (ltype);
/* Evaluate the result */
Expr->ConstVal = kcalc (tok, Expr->ConstVal, lval2.ConstVal);
} else {
/* If the right hand side is constant, and the generator function
* expects the lhs in the primary, remove the push of the primary
* now.
*/
unsigned flags = 0;
if (rconst) {
flags |= CF_CONST;
if ((Gen->Flags & GEN_NOPUSH) != 0) {
RemoveCode (Mark2);
pop (ltype);
ltype |= CF_REG; /* Value is in register */
}
}
/* Determine the type of the operation result. If the left
* operand is of type char and the right is a constant, or
* if both operands are of type char, we will encode the
* operation as char operation. Otherwise the default
* promotions are used.
*/
if (IsTypeChar (Expr->Type) && (IsTypeChar (lval2.Type) || rconst)) {
flags |= CF_CHAR;
if (IsSignUnsigned (Expr->Type) || IsSignUnsigned (lval2.Type)) {
flags |= CF_UNSIGNED;
}
if (rconst) {
flags |= CF_FORCECHAR;
}
} else {
unsigned rtype = TypeOf (lval2.Type) | (flags & CF_CONST);
flags |= g_typeadjust (ltype, rtype);
}
/* Generate code */
Gen->Func (flags, lval2.ConstVal);
Expr->Flags = E_MEXPR | E_RVAL;
}
/* Result type is always int */
Expr->Type = type_int;
/* Condition codes are set */
Expr->Test |= E_CC;
}
}
static void hie9 (ExprDesc *Expr)
/* Process * and / operators. */
{
static const GenDesc hie9_ops[] = {
{ TOK_STAR, GEN_NOPUSH, g_mul },
{ TOK_DIV, GEN_NOPUSH, g_div },
{ TOK_MOD, GEN_NOPUSH, g_mod },
{ TOK_INVALID, 0, 0 }
};
int UsedGen;
hie_internal (hie9_ops, Expr, hie10, &UsedGen);
}
static void parseadd (ExprDesc* Expr)
/* Parse an expression with the binary plus operator. Expr contains the
* unprocessed left hand side of the expression and will contain the
* result of the expression on return.
*/
{
ExprDesc lval2;
unsigned flags; /* Operation flags */
CodeMark Mark; /* Remember code position */
type* lhst; /* Type of left hand side */
type* rhst; /* Type of right hand side */
/* Skip the PLUS token */
NextToken ();
/* Get the left hand side type, initialize operation flags */
lhst = Expr->Type;
flags = 0;
/* Check for constness on both sides */
if (ED_IsRVal (Expr) && (Expr->Flags & E_MCONST) != 0) {
/* The left hand side is a constant. Good. Get rhs */
hie9 (&lval2);
if (ED_IsRVal (&lval2) && lval2.Flags == E_MCONST) {
/* Right hand side is also constant. Get the rhs type */
rhst = lval2.Type;
/* Both expressions are constants. Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
Expr->ConstVal += lval2.ConstVal * CheckedPSizeOf (lhst);
/* Result type is a pointer */
} else if (IsClassInt (lhst) && IsClassPtr (rhst)) {
/* Left is int, right is pointer, must scale lhs */
Expr->ConstVal = Expr->ConstVal * CheckedPSizeOf (rhst) + lval2.ConstVal;
/* Result type is a pointer */
Expr->Type = lval2.Type;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer addition */
Expr->ConstVal += lval2.ConstVal;
typeadjust (Expr, &lval2, 1);
} else {
/* OOPS */
Error ("Invalid operands for binary operator `+'");
}
} else {
/* lhs is a constant and rhs is not constant. Load rhs into
* the primary.
*/
ExprLoad (CF_NONE, &lval2);
/* Beware: The check above (for lhs) lets not only pass numeric
* constants, but also constant addresses (labels), maybe even
* with an offset. We have to check for that here.
*/
/* First, get the rhs type. */
rhst = lval2.Type;
/* Setup flags */
if (Expr->Flags == E_MCONST) {
/* A numerical constant */
flags |= CF_CONST;
} else {
/* Constant address label */
flags |= GlobalModeFlags (Expr->Flags) | CF_CONSTADDR;
}
/* Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
g_scale (CF_INT, CheckedPSizeOf (lhst));
/* Operate on pointers, result type is a pointer */
flags |= CF_PTR;
/* Generate the code for the add */
if (Expr->Flags == E_MCONST) {
/* Numeric constant */
g_inc (flags, Expr->ConstVal);
} else {
/* Constant address */
g_addaddr_static (flags, Expr->Name, Expr->ConstVal);
}
} else if (IsClassInt (lhst) && IsClassPtr (rhst)) {
/* Left is int, right is pointer, must scale lhs. */
unsigned ScaleFactor = CheckedPSizeOf (rhst);
/* Operate on pointers, result type is a pointer */
flags |= CF_PTR;
Expr->Type = lval2.Type;
/* Since we do already have rhs in the primary, if lhs is
* not a numeric constant, and the scale factor is not one
* (no scaling), we must take the long way over the stack.
*/
if (Expr->Flags == E_MCONST) {
/* Numeric constant, scale lhs */
Expr->ConstVal *= ScaleFactor;
/* Generate the code for the add */
g_inc (flags, Expr->ConstVal);
} else if (ScaleFactor == 1) {
/* Constant address but no need to scale */
g_addaddr_static (flags, Expr->Name, Expr->ConstVal);
} else {
/* Constant address that must be scaled */
g_push (TypeOf (lval2.Type), 0); /* rhs --> stack */
g_getimmed (flags, Expr->Name, Expr->ConstVal);
g_scale (CF_PTR, ScaleFactor);
g_add (CF_PTR, 0);
}
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer addition */
flags |= typeadjust (Expr, &lval2, 1);
/* Generate the code for the add */
if (Expr->Flags == E_MCONST) {
/* Numeric constant */
g_inc (flags, Expr->ConstVal);
} else {
/* Constant address */
g_addaddr_static (flags, Expr->Name, Expr->ConstVal);
}
} else {
/* OOPS */
Error ("Invalid operands for binary operator `+'");
}
/* Result is a rvalue in primary register */
Expr->Flags = E_MEXPR | E_RVAL;
}
} else {
/* Left hand side is not constant. Get the value onto the stack. */
ExprLoad (CF_NONE, Expr); /* --> primary register */
Mark = GetCodePos ();
g_push (TypeOf (Expr->Type), 0); /* --> stack */
/* Evaluate the rhs */
if (evalexpr (CF_NONE, hie9, &lval2) == 0) {
/* Right hand side is a constant. Get the rhs type */
rhst = lval2.Type;
/* Remove pushed value from stack */
RemoveCode (Mark);
pop (TypeOf (Expr->Type));
/* Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
lval2.ConstVal *= CheckedPSizeOf (lhst);
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
} else if (IsClassInt (lhst) && IsClassPtr (rhst)) {
/* Left is int, right is pointer, must scale lhs (ptr only) */
g_scale (CF_INT | CF_CONST, CheckedPSizeOf (rhst));
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
Expr->Type = lval2.Type;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer addition */
flags = typeadjust (Expr, &lval2, 1);
} else {
/* OOPS */
Error ("Invalid operands for binary operator `+'");
}
/* Generate code for the add */
g_inc (flags | CF_CONST, lval2.ConstVal);
} else {
/* lhs and rhs are not constant. Get the rhs type. */
rhst = lval2.Type;
/* Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
g_scale (CF_INT, CheckedPSizeOf (lhst));
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
} else if (IsClassInt (lhst) && IsClassPtr (rhst)) {
/* Left is int, right is pointer, must scale lhs */
g_tosint (TypeOf (rhst)); /* Make sure, TOS is int */
g_swap (CF_INT); /* Swap TOS and primary */
g_scale (CF_INT, CheckedPSizeOf (rhst));
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
Expr->Type = lval2.Type;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer addition. Note: Result is never constant.
* Problem here is that typeadjust does not know if the
* variable is an rvalue or lvalue, so if both operands
* are dereferenced constant numeric addresses, typeadjust
* thinks the operation works on constants. Removing
* CF_CONST here means handling the symptoms, however, the
* whole parser is such a mess that I fear to break anything
* when trying to apply another solution.
*/
flags = typeadjust (Expr, &lval2, 0) & ~CF_CONST;
} else {
/* OOPS */
Error ("Invalid operands for binary operator `+'");
}
/* Generate code for the add */
g_add (flags, 0);
}
/* Result is a rvalue in primary register */
Expr->Flags = E_MEXPR | E_RVAL;
}
/* Condition codes not set */
Expr->Test &= ~E_CC;
}
static void parsesub (ExprDesc* Expr)
/* Parse an expression with the binary minus operator. Expr contains the
* unprocessed left hand side of the expression and will contain the
* result of the expression on return.
*/
{
ExprDesc lval2;
unsigned flags; /* Operation flags */
type* lhst; /* Type of left hand side */
type* rhst; /* Type of right hand side */
CodeMark Mark1; /* Save position of output queue */
CodeMark Mark2; /* Another position in the queue */
int rscale; /* Scale factor for the result */
/* Skip the MINUS token */
NextToken ();
/* Get the left hand side type, initialize operation flags */
lhst = Expr->Type;
flags = 0;
rscale = 1; /* Scale by 1, that is, don't scale */
/* Remember the output queue position, then bring the value onto the stack */
Mark1 = GetCodePos ();
ExprLoad (CF_NONE, Expr); /* --> primary register */
Mark2 = GetCodePos ();
g_push (TypeOf (lhst), 0); /* --> stack */
/* Parse the right hand side */
if (evalexpr (CF_NONE, hie9, &lval2) == 0) {
/* The right hand side is constant. Get the rhs type. */
rhst = lval2.Type;
/* Check left hand side */
if (ED_IsRVal (Expr) && (Expr->Flags & E_MCONST) != 0) {
/* Both sides are constant, remove generated code */
RemoveCode (Mark1);
pop (TypeOf (lhst)); /* Clean up the stack */
/* Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
Expr->ConstVal -= lval2.ConstVal * CheckedPSizeOf (lhst);
/* Operate on pointers, result type is a pointer */
} else if (IsClassPtr (lhst) && IsClassPtr (rhst)) {
/* Left is pointer, right is pointer, must scale result */
if (TypeCmp (Indirect (lhst), Indirect (rhst)) < TC_QUAL_DIFF) {
Error ("Incompatible pointer types");
} else {
Expr->ConstVal = (Expr->ConstVal - lval2.ConstVal) /
CheckedPSizeOf (lhst);
}
/* Operate on pointers, result type is an integer */
Expr->Type = type_int;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer subtraction */
typeadjust (Expr, &lval2, 1);
Expr->ConstVal -= lval2.ConstVal;
} else {
/* OOPS */
Error ("Invalid operands for binary operator `-'");
}
/* Result is constant, condition codes not set */
/* Expr->Flags = E_MCONST; ### */
Expr->Test &= ~E_CC;
} else {
/* Left hand side is not constant, right hand side is.
* Remove pushed value from stack.
*/
RemoveCode (Mark2);
pop (TypeOf (lhst));
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
lval2.ConstVal *= CheckedPSizeOf (lhst);
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
} else if (IsClassPtr (lhst) && IsClassPtr (rhst)) {
/* Left is pointer, right is pointer, must scale result */
if (TypeCmp (Indirect (lhst), Indirect (rhst)) < TC_QUAL_DIFF) {
Error ("Incompatible pointer types");
} else {
rscale = CheckedPSizeOf (lhst);
}
/* Operate on pointers, result type is an integer */
flags = CF_PTR;
Expr->Type = type_int;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer subtraction */
flags = typeadjust (Expr, &lval2, 1);
} else {
/* OOPS */
Error ("Invalid operands for binary operator `-'");
}
/* Do the subtraction */
g_dec (flags | CF_CONST, lval2.ConstVal);
/* If this was a pointer subtraction, we must scale the result */
if (rscale != 1) {
g_scale (flags, -rscale);
}
/* Result is a rvalue in the primary register */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->Test &= ~E_CC;
}
} else {
/* Right hand side is not constant. Get the rhs type. */
rhst = lval2.Type;
/* Check for pointer arithmetic */
if (IsClassPtr (lhst) && IsClassInt (rhst)) {
/* Left is pointer, right is int, must scale rhs */
g_scale (CF_INT, CheckedPSizeOf (lhst));
/* Operate on pointers, result type is a pointer */
flags = CF_PTR;
} else if (IsClassPtr (lhst) && IsClassPtr (rhst)) {
/* Left is pointer, right is pointer, must scale result */
if (TypeCmp (Indirect (lhst), Indirect (rhst)) < TC_QUAL_DIFF) {
Error ("Incompatible pointer types");
} else {
rscale = CheckedPSizeOf (lhst);
}
/* Operate on pointers, result type is an integer */
flags = CF_PTR;
Expr->Type = type_int;
} else if (IsClassInt (lhst) && IsClassInt (rhst)) {
/* Integer subtraction. If the left hand side descriptor says that
* the lhs is const, we have to remove this mark, since this is no
* longer true, lhs is on stack instead.
*/
if (Expr->Flags == E_MCONST) {
Expr->Flags = E_MEXPR | E_RVAL;
}
/* Adjust operand types */
flags = typeadjust (Expr, &lval2, 0);
} else {
/* OOPS */
Error ("Invalid operands for binary operator `-'");
}
/* Generate code for the sub (the & is a hack here) */
g_sub (flags & ~CF_CONST, 0);
/* If this was a pointer subtraction, we must scale the result */
if (rscale != 1) {
g_scale (flags, -rscale);
}
/* Result is a rvalue in the primary register */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->Test &= ~E_CC;
}
}
static void hie8 (ExprDesc* Expr)
/* Process + and - binary operators. */
{
hie9 (Expr);
while (CurTok.Tok == TOK_PLUS || CurTok.Tok == TOK_MINUS) {
if (CurTok.Tok == TOK_PLUS) {
parseadd (Expr);
} else {
parsesub (Expr);
}
}
}
static void hie7 (ExprDesc* Expr)
/* Parse << and >>. */
{
static const GenDesc hie7_ops [] = {
{ TOK_SHL, GEN_NOPUSH, g_asl },
{ TOK_SHR, GEN_NOPUSH, g_asr },
{ TOK_INVALID, 0, 0 }
};
int UsedGen;
hie_internal (hie7_ops, Expr, hie8, &UsedGen);
}
static void hie6 (ExprDesc* Expr)
/* Handle greater-than type comparators */
{
static const GenDesc hie6_ops [] = {
{ TOK_LT, GEN_NOPUSH, g_lt },
{ TOK_LE, GEN_NOPUSH, g_le },
{ TOK_GE, GEN_NOPUSH, g_ge },
{ TOK_GT, GEN_NOPUSH, g_gt },
{ TOK_INVALID, 0, 0 }
};
hie_compare (hie6_ops, Expr, hie7);
}
static void hie5 (ExprDesc* Expr)
/* Handle == and != */
{
static const GenDesc hie5_ops[] = {
{ TOK_EQ, GEN_NOPUSH, g_eq },
{ TOK_NE, GEN_NOPUSH, g_ne },
{ TOK_INVALID, 0, 0 }
};
hie_compare (hie5_ops, Expr, hie6);
}
static void hie4 (ExprDesc* Expr)
/* Handle & (bitwise and) */
{
static const GenDesc hie4_ops[] = {
{ TOK_AND, GEN_NOPUSH, g_and },
{ TOK_INVALID, 0, 0 }
};
int UsedGen;
hie_internal (hie4_ops, Expr, hie5, &UsedGen);
}
static void hie3 (ExprDesc* Expr)
/* Handle ^ (bitwise exclusive or) */
{
static const GenDesc hie3_ops[] = {
{ TOK_XOR, GEN_NOPUSH, g_xor },
{ TOK_INVALID, 0, 0 }
};
int UsedGen;
hie_internal (hie3_ops, Expr, hie4, &UsedGen);
}
static void hie2 (ExprDesc* Expr)
/* Handle | (bitwise or) */
{
static const GenDesc hie2_ops[] = {
{ TOK_OR, GEN_NOPUSH, g_or },
{ TOK_INVALID, 0, 0 }
};
int UsedGen;
hie_internal (hie2_ops, Expr, hie3, &UsedGen);
}
static void hieAndPP (ExprDesc* Expr)
/* Process "exp && exp" in preprocessor mode (that is, when the parser is
* called recursively from the preprocessor.
*/
{
ExprDesc lval2;
ConstSubExpr (hie2, Expr);
while (CurTok.Tok == TOK_BOOL_AND) {
/* Left hand side must be an int */
if (!IsClassInt (Expr->Type)) {
Error ("Left hand side must be of integer type");
ED_MakeConstInt (Expr, 1);
}
/* Skip the && */
NextToken ();
/* Get rhs */
ConstSubExpr (hie2, &lval2);
/* Since we are in PP mode, all we know about is integers */
if (!IsClassInt (lval2.Type)) {
Error ("Right hand side must be of integer type");
ED_MakeConstInt (&lval2, 1);
}
/* Combine the two */
Expr->ConstVal = (Expr->ConstVal && lval2.ConstVal);
}
}
static void hieOrPP (ExprDesc *Expr)
/* Process "exp || exp" in preprocessor mode (that is, when the parser is
* called recursively from the preprocessor.
*/
{
ExprDesc lval2;
ConstSubExpr (hieAndPP, Expr);
while (CurTok.Tok == TOK_BOOL_OR) {
/* Left hand side must be an int */
if (!IsClassInt (Expr->Type)) {
Error ("Left hand side must be of integer type");
ED_MakeConstInt (Expr, 1);
}
/* Skip the && */
NextToken ();
/* Get rhs */
ConstSubExpr (hieAndPP, &lval2);
/* Since we are in PP mode, all we know about is integers */
if (!IsClassInt (lval2.Type)) {
Error ("Right hand side must be of integer type");
ED_MakeConstInt (&lval2, 1);
}
/* Combine the two */
Expr->ConstVal = (Expr->ConstVal || lval2.ConstVal);
}
}
static void hieAnd (ExprDesc* Expr, unsigned TrueLab, int* BoolOp)
/* Process "exp && exp" */
{
int lab;
ExprDesc lval2;
hie2 (Expr);
if (CurTok.Tok == TOK_BOOL_AND) {
/* Tell our caller that we're evaluating a boolean */
*BoolOp = 1;
/* Get a label that we will use for false expressions */
lab = GetLocalLabel ();
/* If the expr hasn't set condition codes, set the force-test flag */
if ((Expr->Test & E_CC) == 0) {
Expr->Test |= E_FORCETEST;
}
/* Load the value */
ExprLoad (CF_FORCECHAR, Expr);
/* Generate the jump */
g_falsejump (CF_NONE, lab);
/* Parse more boolean and's */
while (CurTok.Tok == TOK_BOOL_AND) {
/* Skip the && */
NextToken ();
/* Get rhs */
hie2 (&lval2);
if ((lval2.Test & E_CC) == 0) {
lval2.Test |= E_FORCETEST;
}
ExprLoad (CF_FORCECHAR, &lval2);
/* Do short circuit evaluation */
if (CurTok.Tok == TOK_BOOL_AND) {
g_falsejump (CF_NONE, lab);
} else {
/* Last expression - will evaluate to true */
g_truejump (CF_NONE, TrueLab);
}
}
/* Define the false jump label here */
g_defcodelabel (lab);
/* The result is an rvalue in primary */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->Test |= E_CC; /* Condition codes are set */
}
}
static void hieOr (ExprDesc *Expr)
/* Process "exp || exp". */
{
ExprDesc lval2;
int BoolOp = 0; /* Did we have a boolean op? */
int AndOp; /* Did we have a && operation? */
unsigned TrueLab; /* Jump to this label if true */
unsigned DoneLab;
/* Get a label */
TrueLab = GetLocalLabel ();
/* Call the next level parser */
hieAnd (Expr, TrueLab, &BoolOp);
/* Any boolean or's? */
if (CurTok.Tok == TOK_BOOL_OR) {
/* If the expr hasn't set condition codes, set the force-test flag */
if ((Expr->Test & E_CC) == 0) {
Expr->Test |= E_FORCETEST;
}
/* Get first expr */
ExprLoad (CF_FORCECHAR, Expr);
/* For each expression jump to TrueLab if true. Beware: If we
* had && operators, the jump is already in place!
*/
if (!BoolOp) {
g_truejump (CF_NONE, TrueLab);
}
/* Remember that we had a boolean op */
BoolOp = 1;
/* while there's more expr */
while (CurTok.Tok == TOK_BOOL_OR) {
/* skip the || */
NextToken ();
/* Get a subexpr */
AndOp = 0;
hieAnd (&lval2, TrueLab, &AndOp);
if ((lval2.Test & E_CC) == 0) {
lval2.Test |= E_FORCETEST;
}
ExprLoad (CF_FORCECHAR, &lval2);
/* If there is more to come, add shortcut boolean eval. */
g_truejump (CF_NONE, TrueLab);
}
/* The result is an rvalue in primary */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->Test |= E_CC; /* Condition codes are set */
}
/* If we really had boolean ops, generate the end sequence */
if (BoolOp) {
DoneLab = GetLocalLabel ();
g_getimmed (CF_INT | CF_CONST, 0, 0); /* Load FALSE */
g_falsejump (CF_NONE, DoneLab);
g_defcodelabel (TrueLab);
g_getimmed (CF_INT | CF_CONST, 1, 0); /* Load TRUE */
g_defcodelabel (DoneLab);
}
}
static void hieQuest (ExprDesc* Expr)
/* Parse the ternary operator */
{
int labf;
int labt;
ExprDesc Expr2; /* Expression 2 */
ExprDesc Expr3; /* Expression 3 */
int Expr2IsNULL; /* Expression 2 is a NULL pointer */
int Expr3IsNULL; /* Expression 3 is a NULL pointer */
type* ResultType; /* Type of result */
/* Call the lower level eval routine */
if (Preprocessing) {
hieOrPP (Expr);
} else {
hieOr (Expr);
}
/* Check if it's a ternary expression */
if (CurTok.Tok == TOK_QUEST) {
NextToken ();
if ((Expr->Test & E_CC) == 0) {
/* Condition codes not set, force a test */
Expr->Test |= E_FORCETEST;
}
ExprLoad (CF_NONE, Expr);
labf = GetLocalLabel ();
g_falsejump (CF_NONE, labf);
/* Parse second expression. Remember for later if it is a NULL pointer
* expression, then load it into the primary.
*/
expr (hie1, &Expr2);
Expr2IsNULL = IsNullPtr (&Expr2);
if (!IsTypeVoid (Expr2.Type)) {
/* Load it into the primary */
ExprLoad (CF_NONE, &Expr2);
Expr2.Flags = E_MEXPR | E_RVAL;
}
labt = GetLocalLabel ();
ConsumeColon ();
g_jump (labt);
/* Jump here if the first expression was false */
g_defcodelabel (labf);
/* Parse second expression. Remember for later if it is a NULL pointer
* expression, then load it into the primary.
*/
expr (hie1, &Expr3);
Expr3IsNULL = IsNullPtr (&Expr3);
if (!IsTypeVoid (Expr3.Type)) {
/* Load it into the primary */
ExprLoad (CF_NONE, &Expr3);
Expr3.Flags = E_MEXPR | E_RVAL;
}
/* Check if any conversions are needed, if so, do them.
* Conversion rules for ?: expression are:
* - if both expressions are int expressions, default promotion
* rules for ints apply.
* - if both expressions are pointers of the same type, the
* result of the expression is of this type.
* - if one of the expressions is a pointer and the other is
* a zero constant, the resulting type is that of the pointer
* type.
* - if both expressions are void expressions, the result is of
* type void.
* - all other cases are flagged by an error.
*/
if (IsClassInt (Expr2.Type) && IsClassInt (Expr3.Type)) {
/* Get common type */
ResultType = promoteint (Expr2.Type, Expr3.Type);
/* Convert the third expression to this type if needed */
TypeConversion (&Expr3, ResultType);
/* Setup a new label so that the expr3 code will jump around
* the type cast code for expr2.
*/
labf = GetLocalLabel (); /* Get new label */
g_jump (labf); /* Jump around code */
/* The jump for expr2 goes here */
g_defcodelabel (labt);
/* Create the typecast code for expr2 */
TypeConversion (&Expr2, ResultType);
/* Jump here around the typecase code. */
g_defcodelabel (labf);
labt = 0; /* Mark other label as invalid */
} else if (IsClassPtr (Expr2.Type) && IsClassPtr (Expr3.Type)) {
/* Must point to same type */
if (TypeCmp (Indirect (Expr2.Type), Indirect (Expr3.Type)) < TC_EQUAL) {
Error ("Incompatible pointer types");
}
/* Result has the common type */
ResultType = Expr2.Type;
} else if (IsClassPtr (Expr2.Type) && Expr3IsNULL) {
/* Result type is pointer, no cast needed */
ResultType = Expr2.Type;
} else if (Expr2IsNULL && IsClassPtr (Expr3.Type)) {
/* Result type is pointer, no cast needed */
ResultType = Expr3.Type;
} else if (IsTypeVoid (Expr2.Type) && IsTypeVoid (Expr3.Type)) {
/* Result type is void */
ResultType = Expr3.Type;
} else {
Error ("Incompatible types");
ResultType = Expr2.Type; /* Doesn't matter here */
}
/* If we don't have the label defined until now, do it */
if (labt) {
g_defcodelabel (labt);
}
/* Setup the target expression */
Expr->Flags = E_MEXPR | E_RVAL;
Expr->Type = ResultType;
}
}
static void opeq (const GenDesc* Gen, ExprDesc* Expr)
/* Process "op=" operators. */
{
ExprDesc lval2;
unsigned flags;
CodeMark Mark;
int MustScale;
NextToken ();
if (ED_IsRVal (Expr)) {
Error ("Invalid lvalue in assignment");
return;
}
/* Determine the type of the lhs */
flags = TypeOf (Expr->Type);
MustScale = (Gen->Func == g_add || Gen->Func == g_sub) &&
Expr->Type [0] == T_PTR;
/* Get the lhs address on stack (if needed) */
PushAddr (Expr);
/* Fetch the lhs into the primary register if needed */
ExprLoad (CF_NONE, Expr);
/* Bring the lhs on stack */
Mark = GetCodePos ();
g_push (flags, 0);
/* Evaluate the rhs */
if (evalexpr (CF_NONE, hie1, &lval2) == 0) {
/* The resulting value is a constant. If the generator has the NOPUSH
* flag set, don't push the lhs.
*/
if (Gen->Flags & GEN_NOPUSH) {
RemoveCode (Mark);
pop (flags);
}
if (MustScale) {
/* lhs is a pointer, scale rhs */
lval2.ConstVal *= CheckedSizeOf (Expr->Type+1);
}
/* If the lhs is character sized, the operation may be later done
* with characters.
*/
if (CheckedSizeOf (Expr->Type) == SIZEOF_CHAR) {
flags |= CF_FORCECHAR;
}
/* Special handling for add and sub - some sort of a hack, but short code */
if (Gen->Func == g_add) {
g_inc (flags | CF_CONST, lval2.ConstVal);
} else if (Gen->Func == g_sub) {
g_dec (flags | CF_CONST, lval2.ConstVal);
} else {
Gen->Func (flags | CF_CONST, lval2.ConstVal);
}
} else {
/* rhs is not constant and already in the primary register */
if (MustScale) {
/* lhs is a pointer, scale rhs */
g_scale (TypeOf (lval2.Type), CheckedSizeOf (Expr->Type+1));
}
/* If the lhs is character sized, the operation may be later done
* with characters.
*/
if (CheckedSizeOf (Expr->Type) == SIZEOF_CHAR) {
flags |= CF_FORCECHAR;
}
/* Adjust the types of the operands if needed */
Gen->Func (g_typeadjust (flags, TypeOf (lval2.Type)), 0);
}
Store (Expr, 0);
Expr->Flags = E_MEXPR | E_RVAL;
}
static void addsubeq (const GenDesc* Gen, ExprDesc *Expr)
/* Process the += and -= operators */
{
ExprDesc lval2;
unsigned lflags;
unsigned rflags;
int MustScale;
/* We must have an lvalue */
if (ED_IsRVal (Expr)) {
Error ("Invalid lvalue in assignment");
return;
}
/* We're currently only able to handle some adressing modes */
if ((Expr->Flags & E_MGLOBAL) == 0 && /* Global address? */
(Expr->Flags & E_MLOCAL) == 0 && /* Local address? */
(Expr->Flags & E_MCONST) == 0) { /* Constant address? */
/* Use generic routine */
opeq (Gen, Expr);
return;
}
/* Skip the operator */
NextToken ();
/* Check if we have a pointer expression and must scale rhs */
MustScale = (Expr->Type [0] == T_PTR);
/* Initialize the code generator flags */
lflags = 0;
rflags = 0;
/* Evaluate the rhs */
hie1 (&lval2);
if (ED_IsRVal (&lval2) && lval2.Flags == E_MCONST) {
/* The resulting value is a constant. */
if (MustScale) {
/* lhs is a pointer, scale rhs */
lval2.ConstVal *= CheckedSizeOf (Expr->Type+1);
}
rflags |= CF_CONST;
lflags |= CF_CONST;
} else {
/* Not constant, load into the primary */
ExprLoad (CF_NONE, &lval2);
if (MustScale) {
/* lhs is a pointer, scale rhs */
g_scale (TypeOf (lval2.Type), CheckedSizeOf (Expr->Type+1));
}
}
/* Setup the code generator flags */
lflags |= TypeOf (Expr->Type) | CF_FORCECHAR;
rflags |= TypeOf (lval2.Type);
/* Convert the type of the lhs to that of the rhs */
g_typecast (lflags, rflags);
/* Output apropriate code */
if (Expr->Flags & E_MGLOBAL) {
/* Static variable */
lflags |= GlobalModeFlags (Expr->Flags);
if (Gen->Tok == TOK_PLUS_ASSIGN) {
g_addeqstatic (lflags, Expr->Name, Expr->ConstVal, lval2.ConstVal);
} else {
g_subeqstatic (lflags, Expr->Name, Expr->ConstVal, lval2.ConstVal);
}
} else if (Expr->Flags & E_MLOCAL) {
/* ref to localvar */
if (Gen->Tok == TOK_PLUS_ASSIGN) {
g_addeqlocal (lflags, Expr->ConstVal, lval2.ConstVal);
} else {
g_subeqlocal (lflags, Expr->ConstVal, lval2.ConstVal);
}
} else if (Expr->Flags & E_MCONST) {
/* ref to absolute address */
lflags |= CF_ABSOLUTE;
if (Gen->Tok == TOK_PLUS_ASSIGN) {
g_addeqstatic (lflags, Expr->ConstVal, 0, lval2.ConstVal);
} else {
g_subeqstatic (lflags, Expr->ConstVal, 0, lval2.ConstVal);
}
} else if (Expr->Flags & E_MEXPR) {
/* Address in a/x. */
if (Gen->Tok == TOK_PLUS_ASSIGN) {
g_addeqind (lflags, Expr->ConstVal, lval2.ConstVal);
} else {
g_subeqind (lflags, Expr->ConstVal, lval2.ConstVal);
}
} else {
Internal ("Invalid addressing mode");
}
/* Expression is a rvalue in the primary now */
Expr->Flags = E_MEXPR | E_RVAL;
}
void hie1 (ExprDesc* Expr)
/* Parse first level of expression hierarchy. */
{
hieQuest (Expr);
switch (CurTok.Tok) {
case TOK_ASSIGN:
Assignment (Expr);
break;
case TOK_PLUS_ASSIGN:
addsubeq (&GenPASGN, Expr);
break;
case TOK_MINUS_ASSIGN:
addsubeq (&GenSASGN, Expr);
break;
case TOK_MUL_ASSIGN:
opeq (&GenMASGN, Expr);
break;
case TOK_DIV_ASSIGN:
opeq (&GenDASGN, Expr);
break;
case TOK_MOD_ASSIGN:
opeq (&GenMOASGN, Expr);
break;
case TOK_SHL_ASSIGN:
opeq (&GenSLASGN, Expr);
break;
case TOK_SHR_ASSIGN:
opeq (&GenSRASGN, Expr);
break;
case TOK_AND_ASSIGN:
opeq (&GenAASGN, Expr);
break;
case TOK_XOR_ASSIGN:
opeq (&GenXOASGN, Expr);
break;
case TOK_OR_ASSIGN:
opeq (&GenOASGN, Expr);
break;
default:
break;
}
}
void hie0 (ExprDesc *Expr)
/* Parse comma operator. */
{
hie1 (Expr);
while (CurTok.Tok == TOK_COMMA) {
NextToken ();
hie1 (Expr);
}
}
int evalexpr (unsigned Flags, void (*Func) (ExprDesc*), ExprDesc* Expr)
/* Will evaluate an expression via the given function. If the result is a
* constant, 0 is returned and the value is put in the Expr struct. If the
* result is not constant, ExprLoad is called to bring the value into the
* primary register and 1 is returned.
*/
{
/* Evaluate */
Func (Expr);
/* Check for a constant expression */
if (ED_IsRVal (Expr) && Expr->Flags == E_MCONST) {
/* Constant expression */
return 0;
} else {
/* Not constant, load into the primary */
ExprLoad (Flags, Expr);
return 1;
}
}
void expr (void (*Func) (ExprDesc*), ExprDesc *Expr)
/* Expression parser; func is either hie0 or hie1. */
{
/* Remember the stack pointer */
int savsp = oursp;
/* Call the expression function */
(*Func) (Expr);
/* Do some checks if code generation is still constistent */
if (savsp != oursp) {
if (Debug) {
fprintf (stderr, "oursp != savesp (%d != %d)\n", oursp, savsp);
} else {
Internal ("oursp != savsp (%d != %d)", oursp, savsp);
}
}
}
void expression1 (ExprDesc* Expr)
/* Evaluate an expression on level 1 (no comma operator) and put it into
* the primary register
*/
{
expr (hie1, InitExprDesc (Expr));
ExprLoad (CF_NONE, Expr);
}
void expression0 (ExprDesc* Expr)
/* Evaluate an expression via hie0 and put it into the primary register */
{
expr (hie0, InitExprDesc (Expr));
ExprLoad (CF_NONE, Expr);
}
void ConstExpr (ExprDesc* Expr)
/* Get a constant value */
{
expr (hie1, InitExprDesc (Expr));
if (ED_IsLVal (Expr) || (Expr->Flags & E_MCONST) == 0) {
Error ("Constant expression expected");
/* To avoid any compiler errors, make the expression a valid const */
ED_MakeConstInt (Expr, 1);
}
}
void ConstIntExpr (ExprDesc* Expr)
/* Get a constant int value */
{
expr (hie1, InitExprDesc (Expr));
if (ED_IsLVal (Expr) || (Expr->Flags & E_MCONST) == 0 || !IsClassInt (Expr->Type)) {
Error ("Constant integer expression expected");
/* To avoid any compiler errors, make the expression a valid const */
ED_MakeConstInt (Expr, 1);
}
}
void intexpr (ExprDesc* lval)
/* Get an integer expression */
{
expression0 (lval);
if (!IsClassInt (lval->Type)) {
Error ("Integer expression expected");
/* To avoid any compiler errors, make the expression a valid int */
ED_MakeConstInt (lval, 1);
}
}