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Merge pull request #366 from dbrotz/fix-313

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Fix signed integer overflow issues
This commit is contained in:
Antonio Niño Díaz
2019-08-17 16:09:09 +01:00
committed by GitHub
parent 88b66f2941 ca6149abcf
commit b8d5dd1824
6 changed files with 170 additions and 33 deletions
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22
src/asm/constexpr.c
View File

@@ -66,7 +66,7 @@ void constexpr_UnaryOp(struct ConstExpression *expr,
result = value;
break;
case T_OP_SUB:
result = -value;
result = -(uint32_t)value;
break;
case T_OP_NOT:
result = ~value;
@@ -155,10 +155,10 @@ void constexpr_BinaryOp(struct ConstExpression *expr,
result = value1 != value2;
break;
case T_OP_ADD:
result = value1 + value2;
result = (uint32_t)value1 + (uint32_t)value2;
break;
case T_OP_SUB:
result = value1 - value2;
result = (uint32_t)value1 - (uint32_t)value2;
break;
case T_OP_XOR:
result = value1 ^ value2;
@@ -181,7 +181,7 @@ void constexpr_BinaryOp(struct ConstExpression *expr,
fatalerror("Shift by too big value: %d",
value2);
result = value1 << value2;
result = (uint32_t)value1 << value2;
break;
case T_OP_SHR:
if (value2 < 0)
@@ -194,17 +194,25 @@ void constexpr_BinaryOp(struct ConstExpression *expr,
result = value1 >> value2;
break;
case T_OP_MUL:
result = value1 * value2;
result = (uint32_t)value1 * (uint32_t)value2;
break;
case T_OP_DIV:
if (value2 == 0)
fatalerror("Division by zero");
result = value1 / value2;
if (value1 == INT32_MIN && value2 == -1) {
warning("Division of min value by -1");
result = INT32_MIN;
} else {
result = value1 / value2;
}
break;
case T_OP_MOD:
if (value2 == 0)
fatalerror("Division by zero");
result = value1 % value2;
if (value1 == INT32_MIN && value2 == -1)
result = 0;
else
result = value1 % value2;
break;
case T_OP_FDIV:
result = math_Div(value1, value2);

36
src/asm/globlex.c
View File

@@ -71,8 +71,9 @@ typedef int32_t(*x2bin) (char ch);
static int32_t ascii2bin(char *s)
{
int32_t radix = 10;
int32_t result = 0;
char *start = s;
uint32_t radix = 10;
uint32_t result = 0;
x2bin convertfunc = char2bin;
switch (*s) {
@@ -101,6 +102,9 @@ static int32_t ascii2bin(char *s)
break;
}
const uint32_t max_q = UINT32_MAX / radix;
const uint32_t max_r = UINT32_MAX % radix;
if (*s == '\0') {
/*
* There are no digits after the radix prefix
@@ -108,15 +112,39 @@ static int32_t ascii2bin(char *s)
*/
yyerror("Invalid integer constant");
} else if (radix == 4) {
int32_t size = 0;
int32_t c;
while (*s != '\0') {
c = convertfunc(*s++);
result = result * 2 + ((c & 2) << 7) + (c & 1);
size++;
}
/*
* Extending a graphics constant longer than 8 pixels,
* the Game Boy tile width, produces a nonsensical result.
*/
if (size > 8) {
warning("Graphics constant '%s' is too long",
start);
}
} else {
while (*s != '\0')
result = result * radix + convertfunc(*s++);
bool overflow = false;
while (*s != '\0') {
int32_t digit = convertfunc(*s++);
if (result > max_q
|| (result == max_q && digit > max_r)) {
overflow = true;
}
result = result * radix + digit;
}
if (overflow)
warning("Integer constant '%s' is too large",
start);
}
return result;

67
src/asm/rpn.c
View File

@@ -347,7 +347,7 @@ void rpn_ADD(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
expr->nVal = (src1->nVal + src2->nVal);
expr->nVal = ((uint32_t)src1->nVal + (uint32_t)src2->nVal);
pushbyte(expr, RPN_ADD);
expr->nRPNPatchSize++;
}
@@ -356,7 +356,7 @@ void rpn_SUB(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
expr->nVal = (src1->nVal - src2->nVal);
expr->nVal = ((uint32_t)src1->nVal - (uint32_t)src2->nVal);
pushbyte(expr, RPN_SUB);
expr->nRPNPatchSize++;
}
@@ -393,15 +393,18 @@ void rpn_SHL(struct Expression *expr, const struct Expression *src1,
{
joinexpr();
if (src1->nVal < 0)
warning("Left shift of negative value: %d", src1->nVal);
if (!expr->isReloc) {
if (src1->nVal < 0)
warning("Left shift of negative value: %d", src1->nVal);
if (src2->nVal < 0)
fatalerror("Shift by negative value: %d", src2->nVal);
else if (src2->nVal >= 32)
fatalerror("Shift by too big value: %d", src2->nVal);
if (src2->nVal < 0)
fatalerror("Shift by negative value: %d", src2->nVal);
else if (src2->nVal >= 32)
fatalerror("Shift by too big value: %d", src2->nVal);
expr->nVal = ((uint32_t)src1->nVal << src2->nVal);
}
expr->nVal = (src1->nVal << src2->nVal);
pushbyte(expr, RPN_SHL);
expr->nRPNPatchSize++;
}
@@ -410,12 +413,16 @@ void rpn_SHR(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
if (src2->nVal < 0)
fatalerror("Shift by negative value: %d", src2->nVal);
else if (src2->nVal >= 32)
fatalerror("Shift by too big value: %d", src2->nVal);
expr->nVal = (src1->nVal >> src2->nVal);
if (!expr->isReloc) {
if (src2->nVal < 0)
fatalerror("Shift by negative value: %d", src2->nVal);
else if (src2->nVal >= 32)
fatalerror("Shift by too big value: %d", src2->nVal);
expr->nVal = (src1->nVal >> src2->nVal);
}
pushbyte(expr, RPN_SHR);
expr->nRPNPatchSize++;
}
@@ -424,7 +431,7 @@ void rpn_MUL(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
expr->nVal = (src1->nVal * src2->nVal);
expr->nVal = ((uint32_t)src1->nVal * (uint32_t)src2->nVal);
pushbyte(expr, RPN_MUL);
expr->nRPNPatchSize++;
}
@@ -433,10 +440,19 @@ void rpn_DIV(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
if (src2->nVal == 0)
fatalerror("Division by zero");
expr->nVal = (src1->nVal / src2->nVal);
if (!expr->isReloc) {
if (src2->nVal == 0)
fatalerror("Division by zero");
if (src1->nVal == INT32_MIN && src2->nVal == -1) {
warning("Division of min value by -1");
expr->nVal = INT32_MIN;
} else {
expr->nVal = (src1->nVal / src2->nVal);
}
}
pushbyte(expr, RPN_DIV);
expr->nRPNPatchSize++;
}
@@ -445,10 +461,17 @@ void rpn_MOD(struct Expression *expr, const struct Expression *src1,
const struct Expression *src2)
{
joinexpr();
if (src2->nVal == 0)
fatalerror("Division by zero");
expr->nVal = (src1->nVal % src2->nVal);
if (!expr->isReloc) {
if (src2->nVal == 0)
fatalerror("Division by zero");
if (src1->nVal == INT32_MIN && src2->nVal == -1)
expr->nVal = 0;
else
expr->nVal = (src1->nVal % src2->nVal);
}
pushbyte(expr, RPN_MOD);
expr->nRPNPatchSize++;
}
@@ -456,7 +479,7 @@ void rpn_MOD(struct Expression *expr, const struct Expression *src1,
void rpn_UNNEG(struct Expression *expr, const struct Expression *src)
{
*expr = *src;
expr->nVal = -expr->nVal;
expr->nVal = -(uint32_t)expr->nVal;
pushbyte(expr, RPN_UNSUB);
expr->nRPNPatchSize++;
}

42
test/asm/overflow.asm Normal file
View File

@@ -0,0 +1,42 @@
SECTION "sec", ROM0
print_x: MACRO
printv x
printt "\n"
ENDM
x = 2147483647
x = x + 1
dl 2147483647+1
print_x
x = -2147483648
x = x - 1
dl -2147483648-1
print_x
x = -2147483648
x = x * -1
dl -2147483648 * -1
print_x
x = -2147483648
x = x / -1
dl -2147483648 / -1
print_x
x = -2147483648
x = x % -1
dl -2147483648 % -1
print_x
x = -1
x = x << 1
dl -1 << 1
print_x
x = 4294967295
x = 4294967296
x = `33333333
x = `333333333

18
test/asm/overflow.out Normal file
View File

@@ -0,0 +1,18 @@
warning: overflow.asm(24):
Division of min value by -1
warning: overflow.asm(25):
Division of min value by -1
warning: overflow.asm(34):
Left shift of negative value: -1
warning: overflow.asm(35):
Left shift of negative value: -1
warning: overflow.asm(39):
Integer constant '4294967296' is too large
warning: overflow.asm(42):
Graphics constant '`333333333' is too long
$80000000
$7FFFFFFF
$80000000
$80000000
$0
$FFFFFFFE

18
test/asm/overflow.out.pipe Normal file
View File

@@ -0,0 +1,18 @@
warning: -(24):
Division of min value by -1
warning: -(25):
Division of min value by -1
warning: -(34):
Left shift of negative value: -1
warning: -(35):
Left shift of negative value: -1
warning: -(39):
Integer constant '4294967296' is too large
warning: -(42):
Graphics constant '`333333333' is too long
$80000000
$7FFFFFFF
$80000000
$80000000
$0
$FFFFFFFE