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// RUN: %clang_analyze_cc1 %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false \
// RUN: -verify
void clang_analyzer_warnIfReached(void);
void clang_analyzer_eval(_Bool);
void test_simplification_adjustment_concrete_int(int b, int c) {
if (b < 0 || b > 1) // b: [0,1]
return;
if (c < -1 || c > 1) // c: [-1,1]
return;
if (c + b != 0) // c + b == 0
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
if (b != 1) // b == 1 --> c + 1 == 0 --> c == -1
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
clang_analyzer_eval(c == -1); // expected-warning{{TRUE}}
// Keep the symbols and the constraints! alive.
(void)(b * c);
return;
}
void test_simplification_adjustment_range(int b, int c) {
if (b < 0 || b > 1) // b: [0,1]
return;
if (c < -1 || c > 1) // c: [-1,1]
return;
if (c + b < -1 || c + b > 0) // c + b: [-1,0]
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
if (b != 1) // b == 1 --> c + 1: [-1,0] --> c: [-2,-1]
return;
// c: [-2,-1] is intersected with the
// already associated range which is [-1,1],
// thus we get c: [-1,-1]
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
clang_analyzer_eval(c == -1); // expected-warning{{TRUE}}
// Keep the symbols and the constraints! alive.
(void)(b * c);
return;
}
void test_simplification_adjustment_to_infeasible_concrete_int(int b, int c) {
if (b < 0 || b > 1) // b: [0,1]
return;
if (c < 0 || c > 1) // c: [0,1]
return;
if (c + b != 0) // c + b == 0
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
if (b != 1) { // b == 1 --> c + 1 == 0 --> c == -1 contradiction
clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
clang_analyzer_eval(c == 0); // expected-warning{{TRUE}}
// Keep the symbols and the constraints! alive.
(void)(b * c);
return;
}
clang_analyzer_warnIfReached(); // no warning
// Keep the symbols and the constraints! alive.
(void)(b * c);
return;
}
void test_simplification_adjustment_to_infeassible_range(int b, int c) {
if (b < 0 || b > 1) // b: [0,1]
return;
if (c < 0 || c > 1) // c: [0,1]
return;
if (c + b < -1 || c + b > 0) // c + b: [-1,0]
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
if (b != 1) // b == 1 --> c + 1: [-1,0] --> c: [-2,-1] contradiction
return;
clang_analyzer_warnIfReached(); // no warning
// Keep the symbols and the constraints! alive.
(void)(b * c);
return;
}
void test_simplification_adjusment_no_infinite_loop(int a, int b, int c) {
if (a == b) // a != b
return;
if (c != 0) // c == 0
return;
if (b != 0) // b == 0
return;
// The above simplification of `b == 0` could result in an infinite loop
// unless we detect that the State is unchanged.
// The loop:
// 1) Simplification of the trivial equivalence class
// "symbol": "(reg_$0<int a>) == (reg_$1<int b>)", "range": "{ [0, 0] }"
// results in
// "symbol": "(reg_$0<int a>) == 0", "range": "{ [0, 0] }" }
// which in turn creates a non-trivial equivalence class
// [ "(reg_$0<int a>) == (reg_$1<int b>)", "(reg_$0<int a>) == 0" ]
// 2) We call assumeSymInclusiveRange("(reg_$0<int a>) == 0")
// and that calls **simplify** on the associated non-trivial equivalence
// class. During the simplification the State does not change, we reached
// the fixpoint.
(void)(a * b * c);
}
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