/* * expr.c * * Ullrich von Bassewitz, 21.06.1998 */ #include #include /* common */ #include "check.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 "typecast.h" #include "typecmp.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 GenMUL = { TOK_STAR, GEN_NOPUSH, g_mul }; static GenDesc GenDIV = { TOK_DIV, GEN_NOPUSH, g_div }; static GenDesc GenMOD = { TOK_MOD, GEN_NOPUSH, g_mod }; static GenDesc GenASL = { TOK_SHL, GEN_NOPUSH, g_asl }; static GenDesc GenASR = { TOK_SHR, GEN_NOPUSH, g_asr }; static GenDesc GenLT = { TOK_LT, GEN_NOPUSH, g_lt }; static GenDesc GenLE = { TOK_LE, GEN_NOPUSH, g_le }; static GenDesc GenGE = { TOK_GE, GEN_NOPUSH, g_ge }; static GenDesc GenGT = { TOK_GT, GEN_NOPUSH, g_gt }; static GenDesc GenEQ = { TOK_EQ, GEN_NOPUSH, g_eq }; static GenDesc GenNE = { TOK_NE, GEN_NOPUSH, g_ne }; static GenDesc GenAND = { TOK_AND, GEN_NOPUSH, g_and }; static GenDesc GenXOR = { TOK_XOR, GEN_NOPUSH, g_xor }; static GenDesc GenOR = { TOK_OR, GEN_NOPUSH, g_or }; 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 */ /*****************************************************************************/ static int hie0 (ExprDesc *lval); /* Parse comma operator. */ static int expr (int (*func) (ExprDesc*), ExprDesc *lval); /* 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; } unsigned assignadjust (type* lhst, ExprDesc* rhs) /* Adjust the type of the right hand expression so that it can be assigned to * the type on the left hand side. This function is used for assignment and * for converting parameters in a function call. It returns the code generator * flags for the operation. The type string of the right hand side will be * set to the type of the left hand side. */ { /* Get the type of the right hand side. Treat function types as * pointer-to-function */ type* rhst = rhs->Type; if (IsTypeFunc (rhst)) { rhst = PointerTo (rhst); } /* After calling this function, rhs will have the type of the lhs */ rhs->Type = lhst; /* First, do some type checking */ if (IsTypeVoid (lhst) || IsTypeVoid (rhst)) { /* If one of the sides are of type void, output a more apropriate * error message. */ Error ("Illegal type"); } else if (IsClassInt (lhst)) { if (IsClassPtr (rhst)) { /* Pointer -> int conversion */ Warning ("Converting pointer to integer without a cast"); } else if (!IsClassInt (rhst)) { Error ("Incompatible types"); } else { /* Convert the rhs to the type of the lhs. */ unsigned flags = TypeOf (rhst); if (rhs->Flags == E_MCONST) { flags |= CF_CONST; } return g_typecast (TypeOf (lhst), flags); } } else if (IsClassPtr (lhst)) { if (IsClassPtr (rhst)) { /* Pointer to pointer assignment is valid, if: * - both point to the same types, or * - the rhs pointer is a void pointer, or * - the lhs pointer is a void pointer. */ if (!IsTypeVoid (Indirect (lhst)) && !IsTypeVoid (Indirect (rhst))) { /* Compare the types */ switch (TypeCmp (lhst, rhst)) { case TC_INCOMPATIBLE: Error ("Incompatible pointer types"); break; case TC_QUAL_DIFF: Error ("Pointer types differ in type qualifiers"); break; default: /* Ok */ break; } } } else if (IsClassInt (rhst)) { /* Int to pointer assignment is valid only for constant zero */ if (rhs->Flags != E_MCONST || rhs->ConstVal != 0) { Warning ("Converting integer to pointer without a cast"); } } else if (IsTypeFuncPtr (lhst) && IsTypeFunc(rhst)) { /* Assignment of function to function pointer is allowed, provided * that both functions have the same parameter list. */ if (TypeCmp (Indirect (lhst), rhst) < TC_EQUAL) { Error ("Incompatible types"); } } else { Error ("Incompatible types"); } } else { Error ("Incompatible types"); } /* Return an int value in all cases where the operands are not both ints */ return CF_INT; } 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 (!AllowRegVarAddr) { 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 (!AllowRegVarAddr) { 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 (int 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 */ { const GenDesc* G; while ((G = *Table) != 0) { if (G->Tok == Tok) { return G; } ++Table; } return 0; } static int istypeexpr (void) /* Return true if some sort of variable or type is waiting (helper for cast * and sizeof() in hie10). */ { SymEntry* Entry; return CurTok.Tok == TOK_LPAREN && ( (NextTok.Tok >= TOK_FIRSTTYPE && NextTok.Tok <= TOK_LASTTYPE) || (NextTok.Tok == TOK_CONST) || (NextTok.Tok == TOK_IDENT && (Entry = FindSym (NextTok.Ident)) != 0 && SymIsTypeDef (Entry))); } void PushAddr (ExprDesc* lval) /* 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 (lval->Flags != E_MREG && (lval->Flags & E_MEXPR)) { /* Push the address (always a pointer) */ g_push (CF_PTR, 0); } } void ConstSubExpr (int (*F) (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. */ { InitExprDesc (Expr); if (F (Expr) != 0 || Expr->Flags != E_MCONST) { Error ("Constant expression expected"); /* To avoid any compiler errors, make the expression a valid const */ MakeConstIntExpr (Expr, 1); } } void CheckBoolExpr (ExprDesc* lval) /* 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 (lval->Type) && !IsClassPtr (lval->Type)) { Error ("Boolean expression expected"); /* To avoid any compiler errors, make the expression a valid int */ MakeConstIntExpr (lval, 1); } } /*****************************************************************************/ /* code */ /*****************************************************************************/ void exprhs (unsigned flags, int k, ExprDesc *lval) /* Put the result of an expression into the primary register */ { int f; f = lval->Flags; if (k) { /* Dereferenced lvalue */ flags |= TypeOf (lval->Type); if (lval->Test & E_FORCETEST) { flags |= CF_TEST; lval->Test &= ~E_FORCETEST; } if (f & E_MGLOBAL) { /* ref to globalvar */ /* Generate code */ flags |= GlobalModeFlags (f); g_getstatic (flags, lval->Name, lval->ConstVal); } else if (f & E_MLOCAL) { /* ref to localvar */ g_getlocal (flags, lval->ConstVal); } else if (f & E_MCONST) { /* ref to absolute address */ g_getstatic (flags | CF_ABSOLUTE, lval->ConstVal, 0); } else if (f == E_MEOFFS) { g_getind (flags, lval->ConstVal); } else if (f != E_MREG) { g_getind (flags, 0); } } else if (f == E_MEOFFS) { /* reference not storable */ flags |= TypeOf (lval->Type); g_inc (flags | CF_CONST, lval->ConstVal); } else if ((f & E_MEXPR) == 0) { /* Constant of some sort, load it into the primary */ LoadConstant (flags, lval); } /* Are we testing this value? */ if (lval->Test & E_FORCETEST) { /* Yes, force a test */ flags |= TypeOf (lval->Type); g_test (flags); lval->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 lval; /* 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). */ 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 */ const SymEntry* LastParam = Func->SymTab->SymTail; FrameSize -= CheckedSizeOf (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 CFlags; 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; } /* Do some optimization: If we have a constant value to push, * use a special function that may optimize. */ CFlags = CF_NONE; if (!Ellipsis && CheckedSizeOf (Param->Type) == 1) { CFlags = CF_FORCECHAR; } Flags = CF_NONE; if (evalexpr (CFlags, hie1, &lval) == 0) { /* A constant value */ Flags |= CF_CONST; } /* If we don't have an argument spec, accept anything, otherwise * convert the actual argument to the type needed. */ if (!Ellipsis) { /* Promote the argument if needed */ assignadjust (Param->Type, &lval); /* If we have a prototype, chars may be pushed as chars */ Flags |= CF_FORCECHAR; } /* Use the type of the argument for the push */ Flags |= TypeOf (lval.Type); /* If this is a fastcall function, don't push the last argument */ if (ParamCount == Func->ParamCount && (Func->Flags & FD_FASTCALL) != 0) { /* Just load the argument into the primary. This is only needed if * we have a constant argument, otherwise the value is already in * the primary. */ if (Flags & CF_CONST) { exprhs (CF_FORCECHAR, 0, &lval); } } else { unsigned ArgSize = sizeofarg (Flags); if (FrameSize > 0) { /* We have the space already allocated, store in the frame */ CHECK (FrameSize >= ArgSize); FrameSize -= ArgSize; FrameOffs -= ArgSize; /* Store */ g_putlocal (Flags | CF_NOKEEP, FrameOffs, lval.ConstVal); } else { /* Push the argument */ g_push (Flags, lval.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 (int k, ExprDesc* lval) /* 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 */ /* Get a pointer to the function descriptor from the type string */ Func = GetFuncDesc (lval->Type); /* Handle function pointers transparently */ IsFuncPtr = IsTypeFuncPtr (lval->Type); if (IsFuncPtr) { /* Check wether it's a fastcall function that has parameters */ IsFastCall = IsFastCallFunc (lval->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 || ((lval->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. */ exprhs (CF_NONE, k, lval); lval->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 (InlineStdFuncs && IsStdFunc ((const char*) lval->Name)) { /* Inline this function */ HandleStdFunc (Func, lval); 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 */ exprhs (CF_NONE, k, lval); } /* Call the function */ g_callind (TypeOf (lval->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 */ ++lval->Type; } else { /* Normal function */ g_call (TypeOf (lval->Type), (const char*) lval->Name, ParamSize); } } static int primary (ExprDesc* lval) /* This is the lowest level of the expression parser. */ { int k; /* Initialize fields in the expression stucture */ lval->Test = 0; /* No test */ lval->Sym = 0; /* Symbol unknown */ /* Character and integer constants. */ if (CurTok.Tok == TOK_ICONST || CurTok.Tok == TOK_CCONST) { lval->Flags = E_MCONST | E_TCONST; lval->Type = CurTok.Type; lval->ConstVal = CurTok.IVal; NextToken (); return 0; } /* Process parenthesized subexpression by calling the whole parser * recursively. */ if (CurTok.Tok == TOK_LPAREN) { NextToken (); InitExprDesc (lval); /* Remove any attributes */ k = hie0 (lval); ConsumeRParen (); return k; } /* 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) { MakeConstIntExpr (lval, 0); return 0; } /* 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"); MakeConstIntExpr (lval, 1); return 0; } /* Identifier? */ if (CurTok.Tok == TOK_IDENT) { SymEntry* Sym; ident Ident; /* Get a pointer to the symbol table entry */ Sym = lval->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 */ lval->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 lval valid */ lval->Flags = E_MLOCAL | E_TLOFFS; lval->Type = type_int; lval->ConstVal = 0; return 0; } /* Check for legal symbol types */ if ((Sym->Flags & SC_CONST) == SC_CONST) { /* Enum or some other numeric constant */ lval->Flags = E_MCONST | E_TCONST; lval->ConstVal = Sym->V.ConstVal; return 0; } else if ((Sym->Flags & SC_FUNC) == SC_FUNC) { /* Function */ lval->Flags = E_MGLOBAL | E_MCONST | E_TGLAB; lval->Name = (unsigned long) Sym->Name; lval->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)); lval->Flags = E_MEXPR; lval->ConstVal = 0; } else { /* Normal parameter */ lval->Flags = E_MLOCAL | E_TLOFFS; lval->ConstVal = Sym->V.Offs; } } else if ((Sym->Flags & SC_REGISTER) == SC_REGISTER) { /* Register variable, zero page based */ lval->Flags = E_MGLOBAL | E_MCONST | E_TREGISTER; lval->Name = Sym->V.R.RegOffs; lval->ConstVal = 0; } else if ((Sym->Flags & SC_STATIC) == SC_STATIC) { /* Static variable */ if (Sym->Flags & (SC_EXTERN | SC_STORAGE)) { lval->Flags = E_MGLOBAL | E_MCONST | E_TGLAB; lval->Name = (unsigned long) Sym->Name; } else { lval->Flags = E_MGLOBAL | E_MCONST | E_TLLAB; lval->Name = Sym->V.Label; } lval->ConstVal = 0; } else { /* Local static variable */ lval->Flags = E_MGLOBAL | E_MCONST | E_TLLAB; lval->Name = Sym->V.Offs; lval->ConstVal = 0; } /* The symbol is referenced now */ Sym->Flags |= SC_REF; if (IsTypeFunc (lval->Type) || IsTypeArray (lval->Type)) { return 0; } return 1; } /* We did not find the symbol. Remember the name, then skip it */ 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); lval->Type = Sym->Type; lval->Flags = E_MGLOBAL | E_MCONST | E_TGLAB; lval->Name = (unsigned long) Sym->Name; lval->ConstVal = 0; return 0; } else { /* Undeclared Variable */ Sym = AddLocalSym (Ident, type_int, SC_AUTO | SC_REF, 0); lval->Flags = E_MLOCAL | E_TLOFFS; lval->Type = type_int; lval->ConstVal = 0; Error ("Undefined symbol: `%s'", Ident); return 1; } } /* String literal? */ if (CurTok.Tok == TOK_SCONST) { lval->Flags = E_MCONST | E_TLIT; lval->ConstVal = CurTok.IVal; lval->Type = GetCharArrayType (GetLiteralPoolOffs () - CurTok.IVal); NextToken (); return 0; } /* ASM statement? */ if (CurTok.Tok == TOK_ASM) { AsmStatement (); lval->Type = type_void; lval->Flags = E_MEXPR; lval->ConstVal = 0; return 0; } /* __AX__ and __EAX__ pseudo values? */ if (CurTok.Tok == TOK_AX || CurTok.Tok == TOK_EAX) { lval->Type = (CurTok.Tok == TOK_AX)? type_uint : type_ulong; lval->Flags = E_MREG; lval->Test &= ~E_CC; lval->ConstVal = 0; NextToken (); return 1; /* May be used as lvalue */ } /* Illegal primary. */ Error ("Expression expected"); MakeConstIntExpr (lval, 1); return 0; } static int arrayref (int k, ExprDesc* lval) /* Handle an array reference */ { unsigned lflags; unsigned rflags; int ConstBaseAddr; int ConstSubAddr; int l; ExprDesc lval2; CodeMark Mark1; CodeMark Mark2; type* tptr1; type* tptr2; /* Skip the bracket */ NextToken (); /* Get the type of left side */ tptr1 = lval->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 = lval->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 */ exprhs (CF_NONE, k, lval); /* 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. */ l = hie0 (&lval2); if (l == 0 && 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 */ exprhs (CF_NONE, k, lval); } 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, this won't work. */ if (IsTypeArray (tptr1) && ((lval->Flags & ~E_MCTYPE) == E_MCONST || (lval->Flags & ~E_MCTYPE) == E_MLOCAL || (lval->Flags & E_MGLOBAL) != 0 || (lval->Flags == E_MEOFFS))) { lval->ConstVal += lval2.ConstVal; } else { /* Pointer - load into primary and remember offset */ if ((lval->Flags & E_MEXPR) == 0 || k != 0) { exprhs (CF_NONE, k, lval); } lval->ConstVal = lval2.ConstVal; lval->Flags = E_MEOFFS; } /* Result is of element type */ lval->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)); /* */ lval->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 (); exprhs (CF_NONE, l, &lval2); tptr2 = lval2.Type; if (IsClassPtr (tptr1)) { /* Get the element type */ lval->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 (lval->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); exprhs (CF_NONE, k, lval); ConstBaseAddr = 0; } else { g_swap (CF_INT); } /* Scale it */ g_scale (TypeOf (tptr1), CheckedSizeOf (lval2.Type)); lval->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 (lval->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 = lval->Type; lval->Type = tptr1; exprhs (CF_NONE, k, lval); lval->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, lval->ConstVal); } else if (lflags == E_MLOCAL) { /* Base address is a local variable address */ if (IsTypeArray (tptr1)) { g_addaddr_local (CF_INT, lval->ConstVal); } else { g_addlocal (CF_PTR, lval->ConstVal); } } else { /* Base address is a static variable address */ unsigned flags = CF_INT; flags |= GlobalModeFlags (lval->Flags); if (IsTypeArray (tptr1)) { g_addaddr_static (flags, lval->Name, lval->ConstVal); } else { g_addstatic (flags, lval->Name, lval->ConstVal); } } } } } lval->Flags = E_MEXPR; end_array: ConsumeRBrack (); return !IsTypeArray (lval->Type); } static int structref (int k, ExprDesc* lval) /* 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"); lval->Type = type_int; return 0; } /* Get the symbol table entry and check for a struct field */ strcpy (Ident, CurTok.Ident); NextToken (); Field = FindStructField (lval->Type, Ident); if (Field == 0) { Error ("Struct/union has no field named `%s'", Ident); lval->Type = type_int; return 0; } /* If we have constant input data, the result is also constant */ flags = lval->Flags & ~E_MCTYPE; if (flags == E_MCONST || (k == 0 && (flags == E_MLOCAL || (flags & E_MGLOBAL) != 0 || lval->Flags == E_MEOFFS))) { lval->ConstVal += Field->V.Offs; } else { if ((flags & E_MEXPR) == 0 || k != 0) { exprhs (CF_NONE, k, lval); } lval->ConstVal = Field->V.Offs; lval->Flags = E_MEOFFS; } lval->Type = Field->Type; return !IsTypeArray (Field->Type); } static int hie11 (ExprDesc *lval) /* Handle compound types (structs and arrays) */ { int k; type* tptr; k = primary (lval); if (CurTok.Tok < TOK_LBRACK || CurTok.Tok > TOK_PTR_REF) { /* Not for us */ return k; } while (1) { if (CurTok.Tok == TOK_LBRACK) { /* Array reference */ k = arrayref (k, lval); } else if (CurTok.Tok == TOK_LPAREN) { /* Function call. Skip the opening parenthesis */ NextToken (); tptr = lval->Type; if (IsTypeFunc (lval->Type) || IsTypeFuncPtr (lval->Type)) { /* Call the function */ FunctionCall (k, lval); /* Result is in the primary register */ lval->Flags = E_MEXPR; /* Set to result */ lval->Type = GetFuncReturn (lval->Type); } else { Error ("Illegal function call"); } k = 0; } else if (CurTok.Tok == TOK_DOT) { if (!IsClassStruct (lval->Type)) { Error ("Struct expected"); } k = structref (0, lval); } else if (CurTok.Tok == TOK_PTR_REF) { tptr = lval->Type; if (tptr[0] != T_PTR || (tptr[1] & T_STRUCT) == 0) { Error ("Struct pointer expected"); } k = structref (k, lval); } else { return k; } } } void Store (ExprDesc* lval, const type* StoreType) /* Store the primary register into the location denoted by lval. If StoreType * is given, use this type when storing instead of lval->Type. If StoreType * is NULL, use lval->Type instead. */ { unsigned Flags; unsigned f = lval->Flags; /* If StoreType was not given, use lval->Type instead */ if (StoreType == 0) { StoreType = lval->Type; } /* Get the code generator flags */ Flags = TypeOf (StoreType); if (f & E_MGLOBAL) { Flags |= GlobalModeFlags (f); if (lval->Test) { /* Just testing */ Flags |= CF_TEST; } /* Generate code */ g_putstatic (Flags, lval->Name, lval->ConstVal); } else if (f & E_MLOCAL) { /* Store an auto variable */ g_putlocal (Flags, lval->ConstVal, 0); } else if (f == E_MEOFFS) { /* Store indirect with offset */ g_putind (Flags, lval->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, lval->ConstVal, 0); } } /* Assume that each one of the stores will invalidate CC */ lval->Test &= ~E_CC; } static void pre_incdec (ExprDesc* lval, void (*inc) (unsigned, unsigned long)) /* Handle --i and ++i */ { int k; unsigned flags; unsigned long val; NextToken (); if ((k = hie10 (lval)) == 0) { Error ("Invalid lvalue"); return; } /* Get the data type */ flags = TypeOf (lval->Type) | CF_FORCECHAR | CF_CONST; /* Get the increment value in bytes */ val = (lval->Type [0] == T_PTR)? CheckedPSizeOf (lval->Type) : 1; /* We're currently only able to handle some adressing modes */ if ((lval->Flags & E_MGLOBAL) == 0 && /* Global address? */ (lval->Flags & E_MLOCAL) == 0 && /* Local address? */ (lval->Flags & E_MCONST) == 0 && /* Constant address? */ (lval->Flags & E_MEXPR) == 0) { /* Address in a/x? */ /* Use generic code. Push the address if needed */ PushAddr (lval); /* Fetch the value */ exprhs (CF_NONE, k, lval); /* Increment value in primary */ inc (flags, val); /* Store the result back */ Store (lval, 0); } else { /* Special code for some addressing modes - use the special += ops */ if (lval->Flags & E_MGLOBAL) { flags |= GlobalModeFlags (lval->Flags); if (inc == g_inc) { g_addeqstatic (flags, lval->Name, lval->ConstVal, val); } else { g_subeqstatic (flags, lval->Name, lval->ConstVal, val); } } else if (lval->Flags & E_MLOCAL) { /* ref to localvar */ if (inc == g_inc) { g_addeqlocal (flags, lval->ConstVal, val); } else { g_subeqlocal (flags, lval->ConstVal, val); } } else if (lval->Flags & E_MCONST) { /* ref to absolute address */ flags |= CF_ABSOLUTE; if (inc == g_inc) { g_addeqstatic (flags, lval->ConstVal, 0, val); } else { g_subeqstatic (flags, lval->ConstVal, 0, val); } } else if (lval->Flags & E_MEXPR) { /* Address in a/x, check if we have an offset */ unsigned Offs = (lval->Flags == E_MEOFFS)? lval->ConstVal : 0; if (inc == g_inc) { g_addeqind (flags, Offs, val); } else { g_subeqind (flags, Offs, val); } } else { Internal ("Invalid addressing mode"); } } /* Result is an expression */ lval->Flags = E_MEXPR; } static void post_incdec (ExprDesc* lval, int k, void (*inc) (unsigned, unsigned long)) /* Handle i-- and i++ */ { unsigned flags; NextToken (); if (k == 0) { Error ("Invalid lvalue"); return; } /* Get the data type */ flags = TypeOf (lval->Type); /* Push the address if needed */ PushAddr (lval); /* Fetch the value and save it (since it's the result of the expression) */ exprhs (CF_NONE, 1, lval); g_save (flags | CF_FORCECHAR); /* If we have a pointer expression, increment by the size of the type */ if (lval->Type[0] == T_PTR) { inc (flags | CF_CONST | CF_FORCECHAR, CheckedSizeOf (lval->Type + 1)); } else { inc (flags | CF_CONST | CF_FORCECHAR, 1); } /* Store the result back */ Store (lval, 0); /* Restore the original value */ g_restore (flags | CF_FORCECHAR); lval->Flags = E_MEXPR; } static void unaryop (int tok, ExprDesc* lval) /* Handle unary -/+ and ~ */ { int k; unsigned flags; NextToken (); k = hie10 (lval); if (k == 0 && (lval->Flags & E_MCONST) != 0) { /* Value is constant */ switch (tok) { case TOK_MINUS: lval->ConstVal = -lval->ConstVal; break; case TOK_PLUS: break; case TOK_COMP: lval->ConstVal = ~lval->ConstVal; break; default: Internal ("Unexpected token: %d", tok); } } else { /* Value is not constant */ exprhs (CF_NONE, k, lval); /* Get the type of the expression */ flags = TypeOf (lval->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); } lval->Flags = E_MEXPR; } } int hie10 (ExprDesc* lval) /* Handle ++, --, !, unary - etc. */ { int k; type* t; switch (CurTok.Tok) { case TOK_INC: pre_incdec (lval, g_inc); return 0; case TOK_DEC: pre_incdec (lval, g_dec); return 0; case TOK_PLUS: case TOK_MINUS: case TOK_COMP: unaryop (CurTok.Tok, lval); return 0; case TOK_BOOL_NOT: NextToken (); if (evalexpr (CF_NONE, hie10, lval) == 0) { /* Constant expression */ lval->ConstVal = !lval->ConstVal; } else { g_bneg (TypeOf (lval->Type)); lval->Test |= E_CC; /* bneg will set cc */ lval->Flags = E_MEXPR; /* say it's an expr */ } return 0; /* expr not storable */ case TOK_STAR: NextToken (); if (evalexpr (CF_NONE, hie10, lval) != 0) { /* Expression is not const, indirect value loaded into primary */ lval->Flags = E_MEXPR; lval->ConstVal = 0; /* Offset is zero now */ } t = lval->Type; if (IsClassPtr (t)) { lval->Type = Indirect (t); } else { Error ("Illegal indirection"); } return 1; case TOK_AND: NextToken (); k = hie10 (lval); /* The & operator may be applied to any lvalue, and it may be * applied to functions, even if they're no lvalues. */ if (k == 0 && !IsTypeFunc (lval->Type)) { /* Allow the & operator with an array */ if (!IsTypeArray (lval->Type)) { Error ("Illegal address"); } } else { t = TypeAlloc (TypeLen (lval->Type) + 2); t [0] = T_PTR; TypeCpy (t + 1, lval->Type); lval->Type = t; } return 0; case TOK_SIZEOF: NextToken (); if (istypeexpr ()) { type Type[MAXTYPELEN]; NextToken (); lval->ConstVal = CheckedSizeOf (ParseType (Type)); ConsumeRParen (); } else { /* Remember the output queue pointer */ CodeMark Mark = GetCodePos (); hie10 (lval); lval->ConstVal = CheckedSizeOf (lval->Type); /* Remove any generated code */ RemoveCode (Mark); } lval->Flags = E_MCONST | E_TCONST; lval->Type = type_uint; lval->Test &= ~E_CC; return 0; default: if (istypeexpr ()) { /* A cast */ return TypeCast (lval); } } k = hie11 (lval); switch (CurTok.Tok) { case TOK_INC: post_incdec (lval, k, g_inc); return 0; case TOK_DEC: post_incdec (lval, k, g_dec); return 0; default: return k; } } static int hie_internal (const GenDesc** ops, /* List of generators */ ExprDesc* lval, /* parent expr's lval */ int (*hienext) (ExprDesc*), int* UsedGen) /* next higher level */ /* Helper function */ { int k; ExprDesc lval2; CodeMark Mark1; CodeMark Mark2; const GenDesc* Gen; token_t tok; /* The operator token */ unsigned ltype, type; int rconst; /* Operand is a constant */ k = hienext (lval); *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 (lval->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 (lval->Type); if (k == 0 && lval->Flags == E_MCONST) { /* Constant value */ Mark2 = GetCodePos (); g_push (ltype | CF_CONST, lval->ConstVal); } else { /* Value not constant */ exprhs (CF_NONE, k, lval); 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 (k == 0 && lval->Flags == E_MCONST && rconst) { /* Both operands are constant, remove the generated code */ RemoveCode (Mark1); pop (ltype); /* Evaluate the result */ lval->ConstVal = kcalc (tok, lval->ConstVal, lval2.ConstVal); /* Get the type of the result */ lval->Type = promoteint (lval->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); lval->Type = promoteint (lval->Type, lval2.Type); /* Generate code */ Gen->Func (type, lval2.ConstVal); lval->Flags = E_MEXPR; } /* We have a rvalue now */ k = 0; } return k; } static int hie_compare (const GenDesc** ops, /* List of generators */ ExprDesc* lval, /* parent expr's lval */ int (*hienext) (ExprDesc*)) /* Helper function for the compare operators */ { int k; ExprDesc lval2; CodeMark Mark1; CodeMark Mark2; const GenDesc* Gen; token_t tok; /* The operator token */ unsigned ltype; int rconst; /* Operand is a constant */ k = hienext (lval); 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 (lval->Type); if (k == 0 && lval->Flags == E_MCONST) { /* Constant value */ Mark2 = GetCodePos (); g_push (ltype | CF_CONST, lval->ConstVal); } else { /* Value not constant */ exprhs (CF_NONE, k, lval); 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 (lval->Type)) { if (!IsClassInt (lval2.Type) && !(IsClassPtr(lval2.Type) && IsNullPtr(lval))) { Error ("Incompatible types"); } } else if (IsClassPtr (lval->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 (lval->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 (k == 0 && lval->Flags == E_MCONST && rconst) { /* Both operands are constant, remove the generated code */ RemoveCode (Mark1); pop (ltype); /* Evaluate the result */ lval->ConstVal = kcalc (tok, lval->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 (lval->Type) && (IsTypeChar (lval2.Type) || rconst)) { flags |= CF_CHAR; if (IsSignUnsigned (lval->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); lval->Flags = E_MEXPR; } /* Result type is always int */ lval->Type = type_int; /* We have a rvalue now, condition codes are set */ k = 0; lval->Test |= E_CC; } return k; } static int hie9 (ExprDesc *lval) /* Process * and / operators. */ { static const GenDesc* hie9_ops [] = { &GenMUL, &GenDIV, &GenMOD, 0 }; int UsedGen; return hie_internal (hie9_ops, lval, hie10, &UsedGen); } static void parseadd (int k, ExprDesc* lval) /* Parse an expression with the binary plus operator. lval 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 = lval->Type; flags = 0; /* Check for constness on both sides */ if (k == 0 && (lval->Flags & E_MCONST) != 0) { /* The left hand side is a constant. Good. Get rhs */ k = hie9 (&lval2); if (k == 0 && 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 */ lval->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 */ lval->ConstVal = lval->ConstVal * CheckedPSizeOf (rhst) + lval2.ConstVal; /* Result type is a pointer */ lval->Type = lval2.Type; } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer addition */ lval->ConstVal += lval2.ConstVal; typeadjust (lval, &lval2, 1); } else { /* OOPS */ Error ("Invalid operands for binary operator `+'"); } /* Result is constant, condition codes not set */ lval->Test &= ~E_CC; } else { /* lhs is a constant and rhs is not constant. Load rhs into * the primary. */ exprhs (CF_NONE, k, &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 (lval->Flags == E_MCONST) { /* A numerical constant */ flags |= CF_CONST; } else { /* Constant address label */ flags |= GlobalModeFlags (lval->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 (lval->Flags == E_MCONST) { /* Numeric constant */ g_inc (flags, lval->ConstVal); } else { /* Constant address */ g_addaddr_static (flags, lval->Name, lval->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; lval->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 (lval->Flags == E_MCONST) { /* Numeric constant, scale lhs */ lval->ConstVal *= ScaleFactor; /* Generate the code for the add */ g_inc (flags, lval->ConstVal); } else if (ScaleFactor == 1) { /* Constant address but no need to scale */ g_addaddr_static (flags, lval->Name, lval->ConstVal); } else { /* Constant address that must be scaled */ g_push (TypeOf (lval2.Type), 0); /* rhs --> stack */ g_getimmed (flags, lval->Name, lval->ConstVal); g_scale (CF_PTR, ScaleFactor); g_add (CF_PTR, 0); } } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer addition */ flags |= typeadjust (lval, &lval2, 1); /* Generate the code for the add */ if (lval->Flags == E_MCONST) { /* Numeric constant */ g_inc (flags, lval->ConstVal); } else { /* Constant address */ g_addaddr_static (flags, lval->Name, lval->ConstVal); } } else { /* OOPS */ Error ("Invalid operands for binary operator `+'"); } /* Result is in primary register */ lval->Flags = E_MEXPR; lval->Test &= ~E_CC; } } else { /* Left hand side is not constant. Get the value onto the stack. */ exprhs (CF_NONE, k, lval); /* --> primary register */ Mark = GetCodePos (); g_push (TypeOf (lval->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 (lval->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; lval->Type = lval2.Type; } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer addition */ flags = typeadjust (lval, &lval2, 1); } else { /* OOPS */ Error ("Invalid operands for binary operator `+'"); } /* Generate code for the add */ g_inc (flags | CF_CONST, lval2.ConstVal); /* Result is in primary register */ lval->Flags = E_MEXPR; lval->Test &= ~E_CC; } 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; lval->Type = lval2.Type; } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer addition */ flags = typeadjust (lval, &lval2, 0); } else { /* OOPS */ Error ("Invalid operands for binary operator `+'"); } /* Generate code for the add */ g_add (flags, 0); /* Result is in primary register */ lval->Flags = E_MEXPR; lval->Test &= ~E_CC; } } } static void parsesub (int k, ExprDesc* lval) /* Parse an expression with the binary minus operator. lval 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 = lval->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 (); exprhs (CF_NONE, k, lval); /* --> 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 (k == 0 && (lval->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 */ lval->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 { lval->ConstVal = (lval->ConstVal - lval2.ConstVal) / CheckedPSizeOf (lhst); } /* Operate on pointers, result type is an integer */ lval->Type = type_int; } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer subtraction */ typeadjust (lval, &lval2, 1); lval->ConstVal -= lval2.ConstVal; } else { /* OOPS */ Error ("Invalid operands for binary operator `-'"); } /* Result is constant, condition codes not set */ /* lval->Flags = E_MCONST; ### */ lval->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; lval->Type = type_int; } else if (IsClassInt (lhst) && IsClassInt (rhst)) { /* Integer subtraction */ flags = typeadjust (lval, &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 in primary register */ lval->Flags = E_MEXPR; lval->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; lval->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 (lval->Flags == E_MCONST) { lval->Flags = E_MEXPR; } /* Adjust operand types */ flags = typeadjust (lval, &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 in primary register */ lval->Flags = E_MEXPR; lval->Test &= ~E_CC; } } static int hie8 (ExprDesc* lval) /* Process + and - binary operators. */ { int k = hie9 (lval); while (CurTok.Tok == TOK_PLUS || CurTok.Tok == TOK_MINUS) { if (CurTok.Tok == TOK_PLUS) { parseadd (k, lval); } else { parsesub (k, lval); } k = 0; } return k; } static int hie7 (ExprDesc *lval) /* Parse << and >>. */ { static const GenDesc* hie7_ops [] = { &GenASL, &GenASR, 0 }; int UsedGen; return hie_internal (hie7_ops, lval, hie8, &UsedGen); } static int hie6 (ExprDesc *lval) /* process greater-than type comparators */ { static const GenDesc* hie6_ops [] = { &GenLT, &GenLE, &GenGE, &GenGT, 0 }; return hie_compare (hie6_ops, lval, hie7); } static int hie5 (ExprDesc *lval) { static const GenDesc* hie5_ops[] = { &GenEQ, &GenNE, 0 }; return hie_compare (hie5_ops, lval, hie6); } static int hie4 (ExprDesc* lval) /* Handle & (bitwise and) */ { static const GenDesc* hie4_ops [] = { &GenAND, 0 }; int UsedGen; return hie_internal (hie4_ops, lval, hie5, &UsedGen); } static int hie3 (ExprDesc *lval) /* Handle ^ (bitwise exclusive or) */ { static const GenDesc* hie3_ops [] = { &GenXOR, 0 }; int UsedGen; return hie_internal (hie3_ops, lval, hie4, &UsedGen); } static int hie2 (ExprDesc *lval) /* Handle | (bitwise or) */ { static const GenDesc* hie2_ops [] = { &GenOR, 0 }; int UsedGen; return hie_internal (hie2_ops, lval, hie3, &UsedGen); } static int hieAndPP (ExprDesc* lval) /* Process "exp && exp" in preprocessor mode (that is, when the parser is * called recursively from the preprocessor. */ { ExprDesc lval2; ConstSubExpr (hie2, lval); while (CurTok.Tok == TOK_BOOL_AND) { /* Left hand side must be an int */ if (!IsClassInt (lval->Type)) { Error ("Left hand side must be of integer type"); MakeConstIntExpr (lval, 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"); MakeConstIntExpr (&lval2, 1); } /* Combine the two */ lval->ConstVal = (lval->ConstVal && lval2.ConstVal); } /* Always a rvalue */ return 0; } static int hieOrPP (ExprDesc *lval) /* Process "exp || exp" in preprocessor mode (that is, when the parser is * called recursively from the preprocessor. */ { ExprDesc lval2; ConstSubExpr (hieAndPP, lval); while (CurTok.Tok == TOK_BOOL_OR) { /* Left hand side must be an int */ if (!IsClassInt (lval->Type)) { Error ("Left hand side must be of integer type"); MakeConstIntExpr (lval, 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"); MakeConstIntExpr (&lval2, 1); } /* Combine the two */ lval->ConstVal = (lval->ConstVal || lval2.ConstVal); } /* Always a rvalue */ return 0; } static int hieAnd (ExprDesc* lval, unsigned TrueLab, int* BoolOp) /* Process "exp && exp" */ { int k; int lab; ExprDesc lval2; k = hie2 (lval); 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 ((lval->Test & E_CC) == 0) { lval->Test |= E_FORCETEST; } /* Load the value */ exprhs (CF_FORCECHAR, k, lval); /* Generate the jump */ g_falsejump (CF_NONE, lab); /* Parse more boolean and's */ while (CurTok.Tok == TOK_BOOL_AND) { /* Skip the && */ NextToken (); /* Get rhs */ k = hie2 (&lval2); if ((lval2.Test & E_CC) == 0) { lval2.Test |= E_FORCETEST; } exprhs (CF_FORCECHAR, k, &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); /* Define the label */ lval->Flags = E_MEXPR; lval->Test |= E_CC; /* Condition codes are set */ k = 0; } return k; } static int hieOr (ExprDesc *lval) /* Process "exp || exp". */ { int k; 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 */ k = hieAnd (lval, 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 ((lval->Test & E_CC) == 0) { lval->Test |= E_FORCETEST; } /* Get first expr */ exprhs (CF_FORCECHAR, k, lval); /* 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; k = hieAnd (&lval2, TrueLab, &AndOp); if ((lval2.Test & E_CC) == 0) { lval2.Test |= E_FORCETEST; } exprhs (CF_FORCECHAR, k, &lval2); /* If there is more to come, add shortcut boolean eval. */ g_truejump (CF_NONE, TrueLab); } lval->Flags = E_MEXPR; lval->Test |= E_CC; /* Condition codes are set */ k = 0; } /* 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); } return k; } static int hieQuest (ExprDesc *lval) /* Parse "lvalue ? exp : exp" */ { int k; int labf; int labt; ExprDesc lval2; /* Expression 2 */ ExprDesc lval3; /* Expression 3 */ type* type2; /* Type of expression 2 */ type* type3; /* Type of expression 3 */ type* rtype; /* Type of result */ k = Preprocessing? hieOrPP (lval) : hieOr (lval); if (CurTok.Tok == TOK_QUEST) { NextToken (); if ((lval->Test & E_CC) == 0) { /* Condition codes not set, force a test */ lval->Test |= E_FORCETEST; } exprhs (CF_NONE, k, lval); labf = GetLocalLabel (); g_falsejump (CF_NONE, labf); /* Parse second expression */ k = expr (hie1, &lval2); type2 = lval2.Type; if (!IsTypeVoid (lval2.Type)) { /* Load it into the primary */ exprhs (CF_NONE, k, &lval2); } labt = GetLocalLabel (); ConsumeColon (); g_jump (labt); /* Parse the third expression */ g_defcodelabel (labf); k = expr (hie1, &lval3); type3 = lval3.Type; if (!IsTypeVoid (lval3.Type)) { /* Load it into the primary */ exprhs (CF_NONE, k, &lval3); } /* 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 (type2) && IsClassInt (type3)) { /* Get common type */ rtype = promoteint (type2, type3); /* Convert the third expression to this type if needed */ g_typecast (TypeOf (rtype), TypeOf (type3)); /* 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 */ g_typecast (TypeOf (rtype), TypeOf (type2)); /* Jump here around the typecase code. */ g_defcodelabel (labf); labt = 0; /* Mark other label as invalid */ } else if (IsClassPtr (type2) && IsClassPtr (type3)) { /* Must point to same type */ if (TypeCmp (Indirect (type2), Indirect (type3)) < TC_EQUAL) { Error ("Incompatible pointer types"); } /* Result has the common type */ rtype = lval2.Type; } else if (IsClassPtr (type2) && IsNullPtr (&lval3)) { /* Result type is pointer, no cast needed */ rtype = lval2.Type; } else if (IsNullPtr (&lval2) && IsClassPtr (type3)) { /* Result type is pointer, no cast needed */ rtype = lval3.Type; } else if (IsTypeVoid (type2) && IsTypeVoid (type3)) { /* Result type is void */ rtype = lval3.Type; } else { Error ("Incompatible types"); rtype = lval2.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 */ lval->Flags = E_MEXPR; lval->Type = rtype; k = 0; } return k; } static void opeq (const GenDesc* Gen, ExprDesc *lval, int k) /* Process "op=" operators. */ { ExprDesc lval2; unsigned flags; CodeMark Mark; int MustScale; NextToken (); if (k == 0) { Error ("Invalid lvalue in assignment"); return; } /* Determine the type of the lhs */ flags = TypeOf (lval->Type); MustScale = (Gen->Func == g_add || Gen->Func == g_sub) && lval->Type [0] == T_PTR; /* Get the lhs address on stack (if needed) */ PushAddr (lval); /* Fetch the lhs into the primary register if needed */ exprhs (CF_NONE, k, lval); /* 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 (lval->Type+1); } /* If the lhs is character sized, the operation may be later done * with characters. */ if (CheckedSizeOf (lval->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 (lval->Type+1)); } /* If the lhs is character sized, the operation may be later done * with characters. */ if (CheckedSizeOf (lval->Type) == SIZEOF_CHAR) { flags |= CF_FORCECHAR; } /* Adjust the types of the operands if needed */ Gen->Func (g_typeadjust (flags, TypeOf (lval2.Type)), 0); } Store (lval, 0); lval->Flags = E_MEXPR; } static void addsubeq (const GenDesc* Gen, ExprDesc *lval, int k) /* Process the += and -= operators */ { ExprDesc lval2; unsigned lflags; unsigned rflags; int MustScale; /* We must have an lvalue */ if (k == 0) { Error ("Invalid lvalue in assignment"); return; } /* We're currently only able to handle some adressing modes */ if ((lval->Flags & E_MGLOBAL) == 0 && /* Global address? */ (lval->Flags & E_MLOCAL) == 0 && /* Local address? */ (lval->Flags & E_MCONST) == 0) { /* Constant address? */ /* Use generic routine */ opeq (Gen, lval, k); return; } /* Skip the operator */ NextToken (); /* Check if we have a pointer expression and must scale rhs */ MustScale = (lval->Type [0] == T_PTR); /* Initialize the code generator flags */ lflags = 0; rflags = 0; /* Evaluate the rhs */ if (evalexpr (CF_NONE, hie1, &lval2) == 0) { /* The resulting value is a constant. */ if (MustScale) { /* lhs is a pointer, scale rhs */ lval2.ConstVal *= CheckedSizeOf (lval->Type+1); } rflags |= CF_CONST; lflags |= CF_CONST; } 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 (lval->Type+1)); } } /* Setup the code generator flags */ lflags |= TypeOf (lval->Type) | CF_FORCECHAR; rflags |= TypeOf (lval2.Type); /* Cast the rhs to the type of the lhs */ g_typecast (lflags, rflags); /* Output apropriate code */ if (lval->Flags & E_MGLOBAL) { /* Static variable */ lflags |= GlobalModeFlags (lval->Flags); if (Gen->Tok == TOK_PLUS_ASSIGN) { g_addeqstatic (lflags, lval->Name, lval->ConstVal, lval2.ConstVal); } else { g_subeqstatic (lflags, lval->Name, lval->ConstVal, lval2.ConstVal); } } else if (lval->Flags & E_MLOCAL) { /* ref to localvar */ if (Gen->Tok == TOK_PLUS_ASSIGN) { g_addeqlocal (lflags, lval->ConstVal, lval2.ConstVal); } else { g_subeqlocal (lflags, lval->ConstVal, lval2.ConstVal); } } else if (lval->Flags & E_MCONST) { /* ref to absolute address */ lflags |= CF_ABSOLUTE; if (Gen->Tok == TOK_PLUS_ASSIGN) { g_addeqstatic (lflags, lval->ConstVal, 0, lval2.ConstVal); } else { g_subeqstatic (lflags, lval->ConstVal, 0, lval2.ConstVal); } } else if (lval->Flags & E_MEXPR) { /* Address in a/x. */ if (Gen->Tok == TOK_PLUS_ASSIGN) { g_addeqind (lflags, lval->ConstVal, lval2.ConstVal); } else { g_subeqind (lflags, lval->ConstVal, lval2.ConstVal); } } else { Internal ("Invalid addressing mode"); } /* Expression is in the primary now */ lval->Flags = E_MEXPR; } int hie1 (ExprDesc* lval) /* Parse first level of expression hierarchy. */ { int k; k = hieQuest (lval); switch (CurTok.Tok) { case TOK_RPAREN: case TOK_SEMI: return k; case TOK_ASSIGN: NextToken (); if (k == 0) { Error ("Invalid lvalue in assignment"); } else { Assignment (lval); } break; case TOK_PLUS_ASSIGN: addsubeq (&GenPASGN, lval, k); break; case TOK_MINUS_ASSIGN: addsubeq (&GenSASGN, lval, k); break; case TOK_MUL_ASSIGN: opeq (&GenMASGN, lval, k); break; case TOK_DIV_ASSIGN: opeq (&GenDASGN, lval, k); break; case TOK_MOD_ASSIGN: opeq (&GenMOASGN, lval, k); break; case TOK_SHL_ASSIGN: opeq (&GenSLASGN, lval, k); break; case TOK_SHR_ASSIGN: opeq (&GenSRASGN, lval, k); break; case TOK_AND_ASSIGN: opeq (&GenAASGN, lval, k); break; case TOK_XOR_ASSIGN: opeq (&GenXOASGN, lval, k); break; case TOK_OR_ASSIGN: opeq (&GenOASGN, lval, k); break; default: return k; } return 0; } static int hie0 (ExprDesc *lval) /* Parse comma operator. */ { int k; k = hie1 (lval); while (CurTok.Tok == TOK_COMMA) { NextToken (); k = hie1 (lval); } return k; } int evalexpr (unsigned flags, int (*f) (ExprDesc*), ExprDesc* lval) /* Will evaluate an expression via the given function. If the result is a * constant, 0 is returned and the value is put in the lval struct. If the * result is not constant, exprhs is called to bring the value into the * primary register and 1 is returned. */ { int k; /* Evaluate */ k = f (lval); if (k == 0 && lval->Flags == E_MCONST) { /* Constant expression */ return 0; } else { /* Not constant, load into the primary */ exprhs (flags, k, lval); return 1; } } static int expr (int (*func) (ExprDesc*), ExprDesc *lval) /* Expression parser; func is either hie0 or hie1. */ { int k; int savsp; savsp = oursp; k = (*func) (lval); /* 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); } } return k; } void expression1 (ExprDesc* lval) /* Evaluate an expression on level 1 (no comma operator) and put it into * the primary register */ { InitExprDesc (lval); exprhs (CF_NONE, expr (hie1, lval), lval); } void expression (ExprDesc* lval) /* Evaluate an expression and put it into the primary register */ { InitExprDesc (lval); exprhs (CF_NONE, expr (hie0, lval), lval); } void ConstExpr (ExprDesc* lval) /* Get a constant value */ { InitExprDesc (lval); if (expr (hie1, lval) != 0 || (lval->Flags & E_MCONST) == 0) { Error ("Constant expression expected"); /* To avoid any compiler errors, make the expression a valid const */ MakeConstIntExpr (lval, 1); } } void ConstIntExpr (ExprDesc* Val) /* Get a constant int value */ { InitExprDesc (Val); if (expr (hie1, Val) != 0 || (Val->Flags & E_MCONST) == 0 || !IsClassInt (Val->Type)) { Error ("Constant integer expression expected"); /* To avoid any compiler errors, make the expression a valid const */ MakeConstIntExpr (Val, 1); } } void intexpr (ExprDesc* lval) /* Get an integer expression */ { expression (lval); if (!IsClassInt (lval->Type)) { Error ("Integer expression expected"); /* To avoid any compiler errors, make the expression a valid int */ MakeConstIntExpr (lval, 1); } } void Test (unsigned Label, int Invert) /* Evaluate a boolean test expression and jump depending on the result of * the test and on Invert. */ { int k; ExprDesc lval; /* Evaluate the expression */ k = expr (hie0, InitExprDesc (&lval)); /* Check for a boolean expression */ CheckBoolExpr (&lval); /* Check for a constant expression */ if (k == 0 && lval.Flags == E_MCONST) { /* Constant rvalue */ if (!Invert && lval.ConstVal == 0) { g_jump (Label); Warning ("Unreachable code"); } else if (Invert && lval.ConstVal != 0) { g_jump (Label); } } else { /* If the expr hasn't set condition codes, set the force-test flag */ if ((lval.Test & E_CC) == 0) { lval.Test |= E_FORCETEST; } /* Load the value into the primary register */ exprhs (CF_FORCECHAR, k, &lval); /* Generate the jump */ if (Invert) { g_truejump (CF_NONE, Label); } else { g_falsejump (CF_NONE, Label); } } } void TestInParens (unsigned Label, int Invert) /* Evaluate a boolean test expression in parenthesis and jump depending on * the result of the test * and on Invert. */ { /* Eat the parenthesis */ ConsumeLParen (); /* Do the test */ Test (Label, Invert); /* Check for the closing brace */ ConsumeRParen (); }