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Merged
paldepind merged 11 commits into from
Oct 24, 2025
Merged

C++: Range analysis measure bounds #20645

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8aaf9f6
C++: Factor out widening of bounds
paldepind Oct 15, 2025
70a8c4f
C++: Add range analysis examples that explode
paldepind Oct 15, 2025
7eacd87
C++: Apply widening based on number of bounds measure
paldepind Oct 15, 2025
8896a72
C++: Add number of bounds test to simple range analysis
paldepind Oct 15, 2025
99103a5
C++: Add additional test for range analysis
paldepind Oct 16, 2025
c1f0f3d
C++: Handle guard phi nodes differently
paldepind Oct 16, 2025
9502d83
C++: Add debug predicates
paldepind Oct 16, 2025
68d4240
C++: Add change note
paldepind Oct 16, 2025
979b05c
C++: Apply suggested fixes from review
paldepind Oct 17, 2025
0badcfd
C++: Address review comments
paldepind Oct 21, 2025
f207404
C++: Accept test changes
paldepind Oct 21, 2025
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202 changes: 202 additions & 0 deletions cpp/ql/test/library-tests/rangeanalysis/SimpleRangeAnalysis/test.c
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Original file line number Diff line number Diff line change
Expand Up @@ -413,6 +413,208 @@ double test_ternary_nested_of_literals(double m, double n, double o, double p, d
return output;
}

unsigned int conditional_nested_guards(unsigned int ip) {
// This tests a combinatorial explosion that can happen from a large number of
// nested linear guards.
unsigned int special_number =
(14 * ip > (2 * ip + 1) * 17 + (2 * ip + 1 + 1) * 17
? 14 * ip
: (2 * ip + 1) * 14 + (2 * ip + 1 + 1) * 17) >
(2 * (ip * 14 + 32) +
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 > (17 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
2 * ip * 14 + (2 * ip + 1) * 17
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 2 * ip * 14 + (2 * ip + 1) * 17) >
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 > (17 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
(14 * ip > (ip + 1) * 17 ? 17 * ip : (ip + 1) * 17)
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 > (17 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 14 * ip > (ip + 1) * 17
? 14 * ip
: (ip + 1) * 14)
? 2 * (ip * 14 + 32) +
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
2 * ip * 14 + (2 * ip + 1) * 17
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 2 * ip * 14 + (2 * ip + 1) * 17)
: 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
(14 * ip > (ip + 1) * 17 ? 17 * ip : (ip + 1) * 17)
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 14 * ip > (ip + 1) * 17
? 14 * ip
: (ip + 1) * 14)
? 14 * ip > (2 * ip + 1) * 17 + (2 * ip + 1 + 1) * 17
? 14 * ip
: (2 * ip + 1) * 14 + (2 * ip + 1 + 1) * 17
: 2 * (ip * 14 + 32) +
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
2 * ip * 14 + (2 * ip + 1) * 17
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 2 * ip * 14 + (2 * ip + 1) * 17) >
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
(14 * ip > (ip + 1) * 17 ? 17 * ip : (ip + 1) * 17)
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 14 * ip > (ip + 1) * 17
? 14 * ip
: (ip + 1) * 14)
? 2 * (ip * 14 + 32) +
(4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
2 * ip * 14 + (2 * ip + 1) * 17
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 2 * ip * 14 + (2 * ip + 1) * 17)
: 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip) >
(14 * ip > (ip + 1) * 17 ? 17 * ip : (ip + 1) * 17)
? 4 * (ip * 14 + 32) +
(2 * ip * 14 + 32) +
2 * (ip * 14 + 64) +
((2 * ip + 1) * 14 >
(14 * (2 * ip) > 17 * ip ? 17 * (2 * ip) : 17 * ip)
? (2 * ip + 1) * 14
: 14 * (2 * ip) > 17 * ip
? 14 * (2 * ip)
: 14 * ip)
: 14 * ip > (ip + 1) * 17
? 14 * ip
: (ip + 1) * 14;
Comment thread
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return special_number;
}

int many_conditional_assignments(int c1, int c2, int c3, int c4, int c5) {
// This tests a combinatorial explosion that can happen from many conditional
// assignments, since each conditional assignment doubles the number of
// bounds.
int x = 0;
if (c1) { x += 748596; }
if (c2) { x += 84652395; }
if (c3) { x += 3675895; }
if (c4) { x += 98634; }
if (c5) { x += 7834985; }
if (c1 && c2) { x += 938457398; }
if (c1 && c3) { x += 73895648; }
if (c1 && c4) { x += 12345432; }
if (c1 && c5) { x += 38847; }
if (c2 && c3) { x += 234; }
// x now has 2^10 bounds, the 10 additions below give (2^10)^10 bounds
int y = x + x + x + x + x + x + x + x + x + x + x + x;
return y;
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}

// Test the comma expression.
unsigned int test_comma01(unsigned int x) {
unsigned int y = x < 100 ? x : 100;
Expand Down