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C++: Add a FP caused by bad range analysis for subtraction.

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This commit is contained in:
Mathias Vorreiter Pedersen
2023-08-15 15:13:53 +01:00
parent 44b734e120
commit 3fb024164b
3 changed files with 35 additions and 0 deletions
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22
cpp/ql/test/library-tests/ir/range-analysis/test.cpp
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@@ -95,3 +95,25 @@ void gotoLoop(bool b1, bool b2)
}
}
}
void test_sub(int x, int y, int n) {
if(x > 0 && x < 500) {
if(y > 0 && y < 10) {
range(x - y); // $ range="<=InitializeParameter: x-1" range=<=498
}
if(n > 0 && n < 100) {
for (int i = 0; i < n; i++)
{
range(n - i); // $ range=<=99 range="<=InitializeParameter: n | Store: n+0"
range(i - n); // $ range="<=InitializeParameter: n | Store: n-2" range=<=97 range="<=Phi: i-1"
}
for (int i = n; i != 0; i--)
{
range(n - i); // $ SPURIOUS: overflow=+
range(i - n); // $ range="<=Phi: i-1" SPURIOUS: overflow=-
}
}
}
}