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clearer comments on and usage of code generator flags with type conversions in the primary register.
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@ -1283,34 +1283,49 @@ void g_tosint (unsigned flags)
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static void g_regchar (unsigned Flags)
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/* Make sure, the value in the primary register is in the range of char. Truncate if necessary */
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static void g_regchar (unsigned to)
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/* Treat the value in the primary register as a char with specified signedness
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** and convert it to an int (whose representation is irrelevent of signedness).
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*/
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{
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unsigned L;
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AddCodeLine ("ldx #$00");
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if ((Flags & CF_UNSIGNED) == 0) {
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/* Sign extend */
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L = GetLocalLabel();
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AddCodeLine ("cmp #$80");
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AddCodeLine ("bcc %s", LocalLabelName (L));
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AddCodeLine ("dex");
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g_defcodelabel (L);
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}
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/* Since char is the smallest type supported here, we never need any info
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** about the original type to "promote from it". However, we have to make
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** sure the entire AX contains the correct char value as an int, since we
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** will almost always use the char value as an int in AX directly in code
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** generation (unless CF_FORCECHAR is specified). That is to say, we don't
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** need the original "from" flags for the first conversion to char, but do
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** need the original "to" flags as the new "from" flags for the conversion
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** to int.
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*/
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g_regint (to | CF_FORCECHAR);
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}
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void g_regint (unsigned Flags)
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/* Make sure, the value in the primary register an int. Convert if necessary */
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void g_regint (unsigned from)
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/* Convert the value in the primary register to an int (whose representation
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** is irrelevent of signedness).
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*/
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{
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switch (Flags & CF_TYPEMASK) {
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switch (from & CF_TYPEMASK) {
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case CF_CHAR:
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if (Flags & CF_FORCECHAR) {
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/* Conversion is from char */
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g_regchar (Flags);
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/* If the original value was forced to use only A, it must be
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** extended from char to fill AX. Otherwise nothing to do here
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** since AX would already have the correct int value.
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*/
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if (from & CF_FORCECHAR) {
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AddCodeLine ("ldx #$00");
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if ((from & CF_UNSIGNED) == 0) {
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/* Sign extend */
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unsigned L = GetLocalLabel();
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AddCodeLine ("cmp #$80");
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AddCodeLine ("bcc %s", LocalLabelName (L));
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AddCodeLine ("dex");
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g_defcodelabel (L);
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}
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break;
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}
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/* FALLTHROUGH */
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@ -1319,21 +1334,27 @@ void g_regint (unsigned Flags)
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break;
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default:
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typeerror (Flags);
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typeerror (from);
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}
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}
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void g_reglong (unsigned Flags)
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/* Make sure, the value in the primary register a long. Convert if necessary */
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void g_reglong (unsigned from)
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/* Convert the value in the primary register to a long (whose representation
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** is irrelevent of signedness).
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*/
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{
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switch (Flags & CF_TYPEMASK) {
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switch (from & CF_TYPEMASK) {
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case CF_CHAR:
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if (Flags & CF_FORCECHAR) {
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/* If the original value was forced to use only A, it must be
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** extended from char to long. Otherwise AX would already have
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** the correct int value to be extened to long.
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*/
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if (from & CF_FORCECHAR) {
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/* Conversion is from char */
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if (Flags & CF_UNSIGNED) {
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if (from & CF_UNSIGNED) {
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if (IS_Get (&CodeSizeFactor) >= 200) {
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AddCodeLine ("ldx #$00");
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AddCodeLine ("stx sreg");
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@ -1343,18 +1364,19 @@ void g_reglong (unsigned Flags)
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}
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} else {
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if (IS_Get (&CodeSizeFactor) >= 366) {
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g_regchar (Flags);
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g_regint (from);
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AddCodeLine ("stx sreg");
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AddCodeLine ("stx sreg+1");
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} else {
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AddCodeLine ("jsr along");
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}
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}
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break;
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}
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/* FALLTHROUGH */
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case CF_INT:
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if (Flags & CF_UNSIGNED) {
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if (from & CF_UNSIGNED) {
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if (IS_Get (&CodeSizeFactor) >= 200) {
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AddCodeLine ("ldy #$00");
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AddCodeLine ("sty sreg");
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@ -1371,7 +1393,7 @@ void g_reglong (unsigned Flags)
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break;
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default:
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typeerror (Flags);
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typeerror (from);
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}
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}
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@ -1508,48 +1530,49 @@ unsigned g_typeadjust (unsigned lhs, unsigned rhs)
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unsigned g_typecast (unsigned lhs, unsigned rhs)
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/* Cast the value in the primary register to the operand size that is flagged
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** by the lhs value. Return the result value.
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unsigned g_typecast (unsigned to, unsigned from)
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/* Cast the value in the primary register to the specified operand size and
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** signedness. Return the result flags.
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*/
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{
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/* Check if a conversion is needed */
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if ((rhs & CF_CONST) == 0) {
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switch (lhs & CF_TYPEMASK) {
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if ((from & CF_CONST) == 0) {
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switch (to & CF_TYPEMASK) {
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case CF_LONG:
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/* We must promote the primary register to long */
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g_reglong (rhs);
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/* We must promote the primary register to long in EAX */
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g_reglong (from);
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break;
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case CF_INT:
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/* We must promote the primary register to int */
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g_regint (rhs);
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/* We must promote the primary register to int in AX */
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g_regint (from);
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break;
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case CF_CHAR:
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/* We must truncate the primary register to char */
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g_regchar (lhs);
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/* We must truncate the primary register to char and then
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** sign-extend it to signed int in AX.
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*/
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g_regchar (to);
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break;
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default:
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typeerror (lhs);
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/* Since we are switching on "to", report an error on it */
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typeerror (to);
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}
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}
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/* Do not need any other action. If the left type is int, and the primary
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/* Do not need any other action. If the "to" type is int, and the primary
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** register is long, it will be automagically truncated. If the right hand
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** side is const, it is not located in the primary register and handled by
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** the expression parser code.
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*/
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/* Result is const if the right hand side was const */
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lhs |= (rhs & CF_CONST);
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to |= (from & CF_CONST);
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/* The resulting type is that of the left hand side (that's why you called
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** this function :-)
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*/
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return lhs;
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/* The resulting type is "to" (that's why you called this function :-) */
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return to;
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}
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@ -208,11 +208,15 @@ void g_toslong (unsigned flags);
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void g_tosint (unsigned flags);
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/* Make sure, the value on TOS is an int. Convert if necessary */
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void g_regint (unsigned Flags);
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/* Make sure, the value in the primary register an int. Convert if necessary */
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void g_regint (unsigned from);
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/* Convert the value in the primary register to an int (whose representation
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** is irrelevent of signedness).
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*/
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void g_reglong (unsigned Flags);
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/* Make sure, the value in the primary register a long. Convert if necessary */
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void g_reglong (unsigned from);
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/* Convert the value in the primary register to a long (whose representation
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** is irrelevent of signedness).
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*/
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unsigned g_typeadjust (unsigned lhs, unsigned rhs);
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/* Adjust the integer operands before doing a binary operation. lhs is a flags
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@ -220,9 +224,9 @@ unsigned g_typeadjust (unsigned lhs, unsigned rhs);
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** in (e)ax. The return value is the flags value for the resulting type.
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*/
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unsigned g_typecast (unsigned lhs, unsigned rhs);
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/* Cast the value in the primary register to the operand size that is flagged
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** by the lhs value. Return the result value.
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unsigned g_typecast (unsigned to, unsigned from);
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/* Cast the value in the primary register to the specified operand size and
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** signedness. Return the result flags.
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*/
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void g_scale (unsigned flags, long val);
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