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Fixed signed char type comparison with unsigned numeric constants.

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acqn 2021-02-22 23:46:26 +08:00 committed by Oliver Schmidt
parent f1c715c455
commit d628772cd1
1 changed files with 5 additions and 19 deletions
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24
src/cc65/expr.c
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@ -2845,7 +2845,7 @@ static void hie_compare (const GenDesc* Ops, /* List of generators */
}
/* Determine the type of the operation. */
if (IsTypeChar (Expr->Type) && rconst) {
if (IsTypeChar (Expr->Type) && rconst && RightSigned) {
/* Left side is unsigned char, right side is constant.
** Determine the minimum and maximum values
@ -2858,20 +2858,6 @@ static void hie_compare (const GenDesc* Ops, /* List of generators */
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
@ -2951,7 +2937,7 @@ static void hie_compare (const GenDesc* Ops, /* List of generators */
if (rconst) {
flags |= CF_FORCECHAR;
}
if (!LeftSigned) {
if (!LeftSigned || !RightSigned) {
flags |= CF_UNSIGNED;
}
} else {
@ -2959,11 +2945,11 @@ static void hie_compare (const GenDesc* Ops, /* List of generators */
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
/* If the comparison is made as unsigned types and the right is a
** constant, we may be able to change the compares to something more
** effective.
*/
if (!LeftSigned && rconst) {
if ((!LeftSigned || !RightSigned) && rconst) {
switch (Tok) {