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// RUN: %clang_analyze_cc1 -verify %s \
// RUN: -analyzer-checker=core,debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false
#define NULL (void *)0
#define UCHAR_MAX (unsigned char)(~0U)
#define CHAR_MAX (char)(UCHAR_MAX & (UCHAR_MAX >> 1))
#define CHAR_MIN (char)(UCHAR_MAX & ~(UCHAR_MAX >> 1))
void clang_analyzer_eval(int);
void clang_analyzer_warnIfReached();
int getInt();
void zeroImpliesEquality(int a, int b) {
clang_analyzer_eval((a - b) == 0); // expected-warning{{UNKNOWN}}
if ((a - b) == 0) {
clang_analyzer_eval(b != a); // expected-warning{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{TRUE}}
clang_analyzer_eval(!(a != b)); // expected-warning{{TRUE}}
clang_analyzer_eval(!(b == a)); // expected-warning{{FALSE}}
return;
}
clang_analyzer_eval((a - b) == 0); // expected-warning{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{FALSE}}
clang_analyzer_eval(b != a); // expected-warning{{TRUE}}
}
void zeroImpliesReversedEqual(int a, int b) {
clang_analyzer_eval((b - a) == 0); // expected-warning{{UNKNOWN}}
if ((b - a) == 0) {
clang_analyzer_eval(b != a); // expected-warning{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{TRUE}}
return;
}
clang_analyzer_eval((b - a) == 0); // expected-warning{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{FALSE}}
clang_analyzer_eval(b != a); // expected-warning{{TRUE}}
}
void canonicalEqual(int a, int b) {
clang_analyzer_eval(a == b); // expected-warning{{UNKNOWN}}
if (a == b) {
clang_analyzer_eval(b == a); // expected-warning{{TRUE}}
return;
}
clang_analyzer_eval(a == b); // expected-warning{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{FALSE}}
}
void test(int a, int b, int c, int d) {
if (a == b && c == d) {
if (a == 0 && b == d) {
clang_analyzer_eval(c == 0); // expected-warning{{TRUE}}
}
c = 10;
if (b == d) {
clang_analyzer_eval(c == 10); // expected-warning{{TRUE}}
clang_analyzer_eval(d == 10); // expected-warning{{UNKNOWN}}
// expected-warning@-1{{FALSE}}
clang_analyzer_eval(b == a); // expected-warning{{TRUE}}
clang_analyzer_eval(a == d); // expected-warning{{TRUE}}
b = getInt();
clang_analyzer_eval(a == d); // expected-warning{{TRUE}}
clang_analyzer_eval(a == b); // expected-warning{{UNKNOWN}}
}
}
if (a != b && b == c) {
if (c == 42) {
clang_analyzer_eval(b == 42); // expected-warning{{TRUE}}
clang_analyzer_eval(a != 42); // expected-warning{{TRUE}}
}
}
}
void testIntersection(int a, int b, int c) {
if (a < 42 && b > 15 && c >= 25 && c <= 30) {
if (a != b)
return;
clang_analyzer_eval(a > 15); // expected-warning{{TRUE}}
clang_analyzer_eval(b < 42); // expected-warning{{TRUE}}
clang_analyzer_eval(a <= 30); // expected-warning{{UNKNOWN}}
if (c == b) {
// For all equal symbols, we should track the minimal common range.
//
// Also, it should be noted that c is dead at this point, but the
// constraint initially associated with c is still around.
clang_analyzer_eval(a >= 25 && a <= 30); // expected-warning{{TRUE}}
clang_analyzer_eval(b >= 25 && b <= 30); // expected-warning{{TRUE}}
}
}
}
void testPromotion(int a, char b) {
if (b > 10) {
if (a == b) {
// FIXME: support transferring char ranges onto equal int symbols
// when char is promoted to int
clang_analyzer_eval(a > 10); // expected-warning{{UNKNOWN}}
clang_analyzer_eval(a <= CHAR_MAX); // expected-warning{{UNKNOWN}}
}
}
}
void testPromotionOnlyTypes(int a, char b) {
if (a == b) {
// FIXME: support transferring char ranges onto equal int symbols
// when char is promoted to int
clang_analyzer_eval(a <= CHAR_MAX); // expected-warning{{UNKNOWN}}
}
}
void testDowncast(int a, unsigned char b) {
if (a <= -10) {
if ((unsigned char)a == b) {
// Even though ranges for a and b do not intersect,
// ranges for (unsigned char)a and b do.
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
}
if (a == b) {
// FIXME: This case on the other hand is different, it shouldn't be
// reachable. However, the corrent symbolic information available
// to the solver doesn't allow it to distinguish this expression
// from the previous one.
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
}
}
}
void testPointers(int *a, int *b, int *c, int *d) {
if (a == b && c == d) {
if (a == NULL && b == d) {
clang_analyzer_eval(c == NULL); // expected-warning{{TRUE}}
}
}
if (a != b && b == c) {
if (c == NULL) {
clang_analyzer_eval(a != NULL); // expected-warning{{TRUE}}
}
}
}
void testDisequalitiesAfter(int a, int b, int c) {
if (a >= 10 && b <= 42) {
if (a == b && c == 15 && c != a) {
clang_analyzer_eval(b != c); // expected-warning{{TRUE}}
clang_analyzer_eval(a != 15); // expected-warning{{TRUE}}
clang_analyzer_eval(b != 15); // expected-warning{{TRUE}}
clang_analyzer_eval(b >= 10); // expected-warning{{TRUE}}
clang_analyzer_eval(a <= 42); // expected-warning{{TRUE}}
}
}
}
void testDisequalitiesBefore(int a, int b, int c) {
if (a >= 10 && b <= 42 && c == 15) {
if (a == b && c != a) {
clang_analyzer_eval(b != c); // expected-warning{{TRUE}}
clang_analyzer_eval(a != 15); // expected-warning{{TRUE}}
clang_analyzer_eval(b != 15); // expected-warning{{TRUE}}
clang_analyzer_eval(b >= 10); // expected-warning{{TRUE}}
clang_analyzer_eval(a <= 42); // expected-warning{{TRUE}}
}
}
}
void avoidInfeasibleConstraintsForClasses(int a, int b) {
if (a >= 0 && a <= 10 && b >= 20 && b <= 50) {
if ((b - a) == 0) {
clang_analyzer_warnIfReached(); // no warning
}
if (a == b) {
clang_analyzer_warnIfReached(); // no warning
}
if (a != b) {
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
} else {
clang_analyzer_warnIfReached(); // no warning
}
}
}
void avoidInfeasibleConstraintforGT(int a, int b) {
int c = b - a;
if (c <= 0)
return;
// c > 0
// b - a > 0
// b > a
if (a != b) {
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
return;
}
clang_analyzer_warnIfReached(); // no warning
// a == b
if (c < 0)
;
}
void avoidInfeasibleConstraintforLT(int a, int b) {
int c = b - a;
if (c >= 0)
return;
// c < 0
// b - a < 0
// b < a
if (a != b) {
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
return;
}
clang_analyzer_warnIfReached(); // no warning
// a == b
if (c < 0)
;
}
void implyDisequalityFromGT(int a, int b) {
if (a > b) {
clang_analyzer_eval(a == b); // expected-warning{{FALSE}}
clang_analyzer_eval(a != b); // expected-warning{{TRUE}}
}
}
void implyDisequalityFromLT(int a, int b) {
if (a < b) {
clang_analyzer_eval(a == b); // expected-warning{{FALSE}}
clang_analyzer_eval(a != b); // expected-warning{{TRUE}}
}
}
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