/* Do some checks if code generation is still constistent */
if (StackPtr != OldSP) {
if (Debug) {
- fprintf (stderr,
- "Code generation messed up!\n"
- "StackPtr is %d, should be %d",
- StackPtr, OldSP);
+ Error ("Code generation messed up: "
+ "StackPtr is %d, should be %d",
+ StackPtr, OldSP);
} else {
- Internal ("StackPtr is %d, should be %d\n", StackPtr, OldSP);
+ Internal ("Code generation messed up: "
+ "StackPtr is %d, should be %d",
+ StackPtr, OldSP);
}
}
}
+static void WarnConstCompareResult (void)
+/* If the result of a comparison is constant, this is suspicious when not in
+ * preprocessor mode.
+ */
+{
+ if (!Preprocessing && IS_Get (&WarnConstComparison) != 0) {
+ Warning ("Result of comparison is constant");
+ }
+}
+
+
+
/*****************************************************************************/
/* code */
/*****************************************************************************/
}
} else {
+ /* Check function attributes */
+ if (Expr->Sym && SymHasAttr (Expr->Sym, atNoReturn)) {
+ /* For now, handle as if a return statement was encountered */
+ F_ReturnFound (CurrentFunc);
+ }
+
/* Check for known standard functions and inline them */
if (Expr->Name != 0) {
int StdFunc = FindStdFunc ((const char*) Expr->Name);
/* If we have a pointer on stack, remove it */
if (PtrOnStack) {
- g_space (- (int) sizeofarg (CF_PTR));
+ g_drop (SIZEOF_PTR);
pop (CF_PTR);
}
break;
case TOK_SCONST:
+ case TOK_WCSCONST:
/* String literal */
- E->Type = GetCharArrayType (GetLiteralPoolOffs () - CurTok.IVal);
+ E->LVal = UseLiteral (CurTok.SVal);
+ E->Type = GetCharArrayType (GetLiteralSize (CurTok.SVal));
E->Flags = E_LOC_LITERAL | E_RTYPE_RVAL;
- E->IVal = CurTok.IVal;
- E->Name = LiteralPoolLabel;
+ E->IVal = 0;
+ E->Name = GetLiteralLabel (CurTok.SVal);
NextToken ();
break;
ExprDesc Subscript;
CodeMark Mark1;
CodeMark Mark2;
+ TypeCode Qualifiers;
Type* ElementType;
Type* tptr1;
* Since we do the necessary checking here, we can rely later on the
* correct types.
*/
+ Qualifiers = T_QUAL_NONE;
if (IsClassPtr (Expr->Type)) {
if (!IsClassInt (Subscript.Type)) {
Error ("Array subscript is not an integer");
/* To avoid any compiler errors, make the expression a valid int */
ED_MakeConstAbsInt (&Subscript, 0);
}
+ if (IsTypeArray (Expr->Type)) {
+ Qualifiers = GetQualifier (Expr->Type);
+ }
ElementType = Indirect (Expr->Type);
} else if (IsClassInt (Expr->Type)) {
if (!IsClassPtr (Subscript.Type)) {
* address 0.
*/
ED_MakeConstAbs (&Subscript, 0, GetCharArrayType (1));
+ } else if (IsTypeArray (Subscript.Type)) {
+ Qualifiers = GetQualifier (Subscript.Type);
}
ElementType = Indirect (Subscript.Type);
} else {
ElementType = Indirect (Expr->Type);
}
+ /* The element type has the combined qualifiers from itself and the array,
+ * it is a member of (if any).
+ */
+ if (GetQualifier (ElementType) != (GetQualifier (ElementType) | Qualifiers)) {
+ ElementType = TypeDup (ElementType);
+ ElementType->C |= Qualifiers;
+ }
+
/* If the subscript is a bit-field, load it and make it an rvalue */
if (ED_IsBitField (&Subscript)) {
LoadExpr (CF_NONE, &Subscript);
{
ident Ident;
SymEntry* Field;
+ Type* FinalType;
+ TypeCode Q;
/* Skip the token and check for an identifier */
NextToken ();
if (CurTok.Tok != TOK_IDENT) {
Error ("Identifier expected");
- Expr->Type = type_int;
+ /* Make the expression an integer at address zero */
+ ED_MakeConstAbs (Expr, 0, type_int);
return;
}
Field = FindStructField (Expr->Type, Ident);
if (Field == 0) {
Error ("Struct/union has no field named `%s'", Ident);
- Expr->Type = type_int;
+ /* Make the expression an integer at address zero */
+ ED_MakeConstAbs (Expr, 0, type_int);
return;
}
ED_MakeLValExpr (Expr);
}
- /* Set the struct field offset */
- Expr->IVal += Field->V.Offs;
-
- /* The type is now the type of the field */
- Expr->Type = Field->Type;
+ /* The type is the type of the field plus any qualifiers from the struct */
+ if (IsClassStruct (Expr->Type)) {
+ Q = GetQualifier (Expr->Type);
+ } else {
+ Q = GetQualifier (Indirect (Expr->Type));
+ }
+ if (GetQualifier (Field->Type) == (GetQualifier (Field->Type) | Q)) {
+ FinalType = Field->Type;
+ } else {
+ FinalType = TypeDup (Field->Type);
+ FinalType->C |= Q;
+ }
- /* An struct member is actually a variable. So the rules for variables
- * with respect to the reference type apply: If it's an array, it is
- * a rvalue, otherwise it's an lvalue. (A function would also be a rvalue,
- * but a struct field cannot be a function).
+ /* A struct is usually an lvalue. If not, it is a struct in the primary
+ * register.
*/
- if (IsTypeArray (Expr->Type)) {
- ED_MakeRVal (Expr);
+ if (ED_IsRVal (Expr) && ED_IsLocExpr (Expr) && !IsTypePtr (Expr->Type)) {
+
+ unsigned Flags = 0;
+ unsigned BitOffs;
+
+ /* Get the size of the type */
+ unsigned Size = SizeOf (Expr->Type);
+
+ /* Safety check */
+ CHECK (Field->V.Offs + Size <= SIZEOF_LONG);
+
+ /* The type of the operation depends on the type of the struct */
+ switch (Size) {
+ case 1: Flags = CF_CHAR | CF_UNSIGNED | CF_CONST; break;
+ case 2: Flags = CF_INT | CF_UNSIGNED | CF_CONST; break;
+ case 3: /* FALLTHROUGH */
+ case 4: Flags = CF_LONG | CF_UNSIGNED | CF_CONST; break;
+ default: Internal ("Invalid struct size: %u", Size); break;
+ }
+
+ /* Generate a shift to get the field in the proper position in the
+ * primary. For bit fields, mask the value.
+ */
+ BitOffs = Field->V.Offs * CHAR_BITS;
+ if (SymIsBitField (Field)) {
+ BitOffs += Field->V.B.BitOffs;
+ g_asr (Flags, BitOffs);
+ /* Mask the value. This is unnecessary if the shift executed above
+ * moved only zeroes into the value.
+ */
+ if (BitOffs + Field->V.B.BitWidth != Size * CHAR_BITS) {
+ g_and (CF_INT | CF_UNSIGNED | CF_CONST,
+ (0x0001U << Field->V.B.BitWidth) - 1U);
+ }
+ } else {
+ g_asr (Flags, BitOffs);
+ }
+
+ /* Use the new type */
+ Expr->Type = FinalType;
+
} else {
- ED_MakeLVal (Expr);
- }
- /* Make the expression a bit field if necessary */
- if (SymIsBitField (Field)) {
- ED_MakeBitField (Expr, Field->V.B.BitOffs, Field->V.B.BitWidth);
+ /* Set the struct field offset */
+ Expr->IVal += Field->V.Offs;
+
+ /* Use the new type */
+ Expr->Type = FinalType;
+
+ /* An struct member is actually a variable. So the rules for variables
+ * with respect to the reference type apply: If it's an array, it is
+ * a rvalue, otherwise it's an lvalue. (A function would also be a rvalue,
+ * but a struct field cannot be a function).
+ */
+ if (IsTypeArray (Expr->Type)) {
+ ED_MakeRVal (Expr);
+ } else {
+ ED_MakeLVal (Expr);
+ }
+
+ /* Make the expression a bit field if necessary */
+ if (SymIsBitField (Field)) {
+ ED_MakeBitField (Expr, Field->V.B.BitOffs, Field->V.B.BitWidth);
+ }
}
+
}
ED_MakeRValExpr (Expr);
}
/* If the expression is already a pointer to function, the
- * additional dereferencing operator must be ignored.
+ * additional dereferencing operator must be ignored. A function
+ * itself is represented as "pointer to function", so any number
+ * of dereference operators is legal, since the result will
+ * always be converted to "pointer to function".
*/
- if (IsTypeFuncPtr (Expr->Type)) {
+ if (IsTypeFuncPtr (Expr->Type) || IsTypeFunc (Expr->Type)) {
/* Expression not storable */
ED_MakeRVal (Expr);
} else {
/* Helper function for the compare operators */
{
ExprDesc Expr2;
+ CodeMark Mark0;
CodeMark Mark1;
CodeMark Mark2;
const GenDesc* Gen;
- token_t Tok; /* The operator token */
+ token_t Tok; /* The operator token */
unsigned ltype;
int rconst; /* Operand is a constant */
+ GetCodePos (&Mark0);
hienext (Expr);
while ((Gen = FindGen (CurTok.Tok, Ops)) != 0) {
+ /* Remember the generator function */
+ void (*GenFunc) (unsigned, unsigned long) = Gen->Func;
+
/* Remember the operator token, then skip it */
Tok = CurTok.Tok;
NextToken ();
/* If the result is constant, this is suspicious when not in
* preprocessor mode.
*/
- if (!Preprocessing) {
- Warning ("Result of comparison is constant");
- }
+ WarnConstCompareResult ();
/* Both operands are constant, remove the generated code */
RemoveCode (&Mark1);
}
}
- } else {
+ } else {
+
+ /* Determine the signedness of the operands */
+ int LeftSigned = IsSignSigned (Expr->Type);
+ int RightSigned = IsSignSigned (Expr2.Type);
/* If the right hand side is constant, and the generator function
* expects the lhs in the primary, remove the push of the primary
}
}
- /* 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 (Expr2.Type) || rconst)) {
- flags |= CF_CHAR;
- if (IsSignUnsigned (Expr->Type) || IsSignUnsigned (Expr2.Type)) {
- flags |= CF_UNSIGNED;
- }
- if (rconst) {
- flags |= CF_FORCECHAR;
- }
+ /* Determine the type of the operation. */
+ if (IsTypeChar (Expr->Type) && rconst) {
+
+ /* Left side is unsigned char, right side is constant.
+ * Determine the minimum and maximum values
+ */
+ int LeftMin, LeftMax;
+ if (LeftSigned) {
+ LeftMin = -128;
+ LeftMax = 127;
+ } else {
+ LeftMin = 0;
+ LeftMax = 255;
+ }
+ /* An integer value is always represented as a signed in the
+ * ExprDesc structure. This may lead to false results below,
+ * if it is actually unsigned, but interpreted as signed
+ * because of the representation. Fortunately, in this case,
+ * the actual value doesn't matter, since it's always greater
+ * than what can be represented in a char. So correct the
+ * value accordingly.
+ */
+ if (!RightSigned && Expr2.IVal < 0) {
+ /* Correct the value so it is an unsigned. It will then
+ * anyway match one of the cases below.
+ */
+ Expr2.IVal = LeftMax + 1;
+ }
+
+ /* Comparing a char against a constant may have a constant
+ * result. Please note: It is not possible to remove the code
+ * for the compare alltogether, because it may have side
+ * effects.
+ */
+ switch (Tok) {
+
+ case TOK_EQ:
+ if (Expr2.IVal < LeftMin || Expr2.IVal > LeftMax) {
+ ED_MakeConstAbsInt (Expr, 0);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ case TOK_NE:
+ if (Expr2.IVal < LeftMin || Expr2.IVal > LeftMax) {
+ ED_MakeConstAbsInt (Expr, 1);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ case TOK_LT:
+ if (Expr2.IVal <= LeftMin || Expr2.IVal > LeftMax) {
+ ED_MakeConstAbsInt (Expr, Expr2.IVal > LeftMax);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ case TOK_LE:
+ if (Expr2.IVal < LeftMin || Expr2.IVal >= LeftMax) {
+ ED_MakeConstAbsInt (Expr, Expr2.IVal >= LeftMax);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ case TOK_GE:
+ if (Expr2.IVal <= LeftMin || Expr2.IVal > LeftMax) {
+ ED_MakeConstAbsInt (Expr, Expr2.IVal <= LeftMin);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ case TOK_GT:
+ if (Expr2.IVal < LeftMin || Expr2.IVal >= LeftMax) {
+ ED_MakeConstAbsInt (Expr, Expr2.IVal < LeftMin);
+ WarnConstCompareResult ();
+ goto Done;
+ }
+ break;
+
+ default:
+ Internal ("hie_compare: got token 0x%X\n", Tok);
+ }
+
+ /* If the result is not already constant (as evaluated in the
+ * switch above), we can execute the operation as a char op,
+ * since the right side constant is in a valid range.
+ */
+ flags |= (CF_CHAR | CF_FORCECHAR);
+ if (!LeftSigned) {
+ flags |= CF_UNSIGNED;
+ }
+
+ } else if (IsTypeChar (Expr->Type) && IsTypeChar (Expr2.Type) &&
+ GetSignedness (Expr->Type) == GetSignedness (Expr2.Type)) {
+
+ /* Both are chars with the same signedness. We can encode the
+ * operation as a char operation.
+ */
+ flags |= CF_CHAR;
+ if (rconst) {
+ flags |= CF_FORCECHAR;
+ }
+ if (!LeftSigned) {
+ flags |= CF_UNSIGNED;
+ }
} else {
- unsigned rtype = TypeOf (Expr2.Type) | (flags & CF_CONST);
+ unsigned rtype = TypeOf (Expr2.Type) | (flags & CF_CONST);
flags |= g_typeadjust (ltype, rtype);
}
+ /* If the left side is an unsigned and the right is a constant,
+ * we may be able to change the compares to something more
+ * effective.
+ */
+ if (!LeftSigned && rconst) {
+
+ switch (Tok) {
+
+ case TOK_LT:
+ if (Expr2.IVal == 1) {
+ /* An unsigned compare to one means that the value
+ * must be zero.
+ */
+ GenFunc = g_eq;
+ Expr2.IVal = 0;
+ }
+ break;
+
+ case TOK_LE:
+ if (Expr2.IVal == 0) {
+ /* An unsigned compare to zero means that the value
+ * must be zero.
+ */
+ GenFunc = g_eq;
+ }
+ break;
+
+ case TOK_GE:
+ if (Expr2.IVal == 1) {
+ /* An unsigned compare to one means that the value
+ * must not be zero.
+ */
+ GenFunc = g_ne;
+ Expr2.IVal = 0;
+ }
+ break;
+
+ case TOK_GT:
+ if (Expr2.IVal == 0) {
+ /* An unsigned compare to zero means that the value
+ * must not be zero.
+ */
+ GenFunc = g_ne;
+ }
+ break;
+
+ default:
+ break;
+
+ }
+
+ }
+
/* Generate code */
- Gen->Func (flags, Expr2.IVal);
+ GenFunc (flags, Expr2.IVal);
/* The result is an rvalue in the primary */
ED_MakeRValExpr (Expr);
/* Result type is always int */
Expr->Type = type_int;
- /* Condition codes are set */
+Done: /* Condition codes are set */
ED_TestDone (Expr);
}
}
-static void opeq (const GenDesc* Gen, ExprDesc* Expr)
+static void opeq (const GenDesc* Gen, ExprDesc* Expr, const char* Op)
/* Process "op=" operators. */
{
ExprDesc Expr2;
/* Evaluate the rhs */
MarkedExprWithCheck (hie1, &Expr2);
+ /* The rhs must be an integer (or a float, but we don't support that yet */
+ if (!IsClassInt (Expr2.Type)) {
+ Error ("Invalid right operand for binary operator `%s'", Op);
+ /* Continue. Wrong code will be generated, but the compiler won't
+ * break, so this is the best error recovery.
+ */
+ }
+
/* Check for a constant expression */
if (ED_IsConstAbs (&Expr2) && ED_CodeRangeIsEmpty (&Expr2)) {
/* The resulting value is a constant. If the generator has the NOPUSH
-static void addsubeq (const GenDesc* Gen, ExprDesc *Expr)
+static void addsubeq (const GenDesc* Gen, ExprDesc *Expr, const char* Op)
/* Process the += and -= operators */
{
ExprDesc Expr2;
/* We're currently only able to handle some adressing modes */
if (ED_GetLoc (Expr) == E_LOC_EXPR || ED_GetLoc (Expr) == E_LOC_PRIMARY) {
/* Use generic routine */
- opeq (Gen, Expr);
+ opeq (Gen, Expr, Op);
return;
}
lflags = 0;
rflags = 0;
- /* Evaluate the rhs */
+ /* Evaluate the rhs. We expect an integer here, since float is not
+ * supported
+ */
hie1 (&Expr2);
+ if (!IsClassInt (Expr2.Type)) {
+ Error ("Invalid right operand for binary operator `%s'", Op);
+ /* Continue. Wrong code will be generated, but the compiler won't
+ * break, so this is the best error recovery.
+ */
+ }
if (ED_IsConstAbs (&Expr2)) {
/* The resulting value is a constant. Scale it. */
if (MustScale) {
break;
case TOK_PLUS_ASSIGN:
- addsubeq (&GenPASGN, Expr);
+ addsubeq (&GenPASGN, Expr, "+=");
break;
case TOK_MINUS_ASSIGN:
- addsubeq (&GenSASGN, Expr);
+ addsubeq (&GenSASGN, Expr, "-=");
break;
case TOK_MUL_ASSIGN:
- opeq (&GenMASGN, Expr);
+ opeq (&GenMASGN, Expr, "*=");
break;
case TOK_DIV_ASSIGN:
- opeq (&GenDASGN, Expr);
+ opeq (&GenDASGN, Expr, "/=");
break;
case TOK_MOD_ASSIGN:
- opeq (&GenMOASGN, Expr);
+ opeq (&GenMOASGN, Expr, "%=");
break;
case TOK_SHL_ASSIGN:
- opeq (&GenSLASGN, Expr);
+ opeq (&GenSLASGN, Expr, "<<=");
break;
case TOK_SHR_ASSIGN:
- opeq (&GenSRASGN, Expr);
+ opeq (&GenSRASGN, Expr, ">>=");
break;
case TOK_AND_ASSIGN:
- opeq (&GenAASGN, Expr);
+ opeq (&GenAASGN, Expr, "&=");
break;
case TOK_XOR_ASSIGN:
- opeq (&GenXOASGN, Expr);
+ opeq (&GenXOASGN, Expr, "^=");
break;
case TOK_OR_ASSIGN:
- opeq (&GenOASGN, Expr);
+ opeq (&GenOASGN, Expr, "|=");
break;
default:
projects / cc65 / blobdiff