/* expr.c * * Ullrich von Bassewitz, 21.06.1998 */ #include #include /* 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); } }