additive-folding-range-constraints.c revision 43d9f0d4e9b88dcab473a359a7b5579c2a619b22 
1// RUN: %clang_cc1 -analyze -analyzer-checker=core,debug.ExprInspection -verify -analyzer-constraints=range %s
2
3void clang_analyzer_eval(int);
4
5#define UINT_MAX (~0U)
6#define INT_MAX (UINT_MAX & (UINT_MAX >> 1))
7#define INT_MIN (-INT_MAX - 1)
8
9
10// Each of these adjusted ranges has an adjustment small enough to split the
11// solution range across an overflow boundary (Min for <, Max for >).
12// This corresponds to one set of branches in RangeConstraintManager.
13void smallAdjustmentGT (unsigned a) {
14  if (a+2 > 1)
15    clang_analyzer_eval(a < UINT_MAX-1); // expected-warning{{TRUE}}
16  else
17    clang_analyzer_eval(a == UINT_MAX-1 || a == UINT_MAX); // expected-warning{{TRUE}}
18}
19
20void smallAdjustmentGE (unsigned a) {
21  if (a+2 >= 1)
22    clang_analyzer_eval(a < UINT_MAX-1 || a == UINT_MAX); // expected-warning{{TRUE}}
23  else
24    clang_analyzer_eval(a == UINT_MAX-1); // expected-warning{{TRUE}}
25}
26
27void smallAdjustmentLT (unsigned a) {
28  if (a+1 < 2)
29    clang_analyzer_eval(a == 0 || a == UINT_MAX); // expected-warning{{TRUE}}
30}
31
32void smallAdjustmentLE (unsigned a) {
33  if (a+1 <= 2)
34    clang_analyzer_eval(a == 0 || a == 1 || a == UINT_MAX); // expected-warning{{TRUE}}
35}
36
37
38// Each of these adjusted ranges has an adjustment large enough to push the
39// comparison value over an overflow boundary (Min for <, Max for >).
40// This corresponds to one set of branches in RangeConstraintManager.
41void largeAdjustmentGT (unsigned a) {
42  if (a-2 > UINT_MAX-1)
43    clang_analyzer_eval(a == 1); // expected-warning{{TRUE}}
44  else
45    clang_analyzer_eval(a != 1); // expected-warning{{TRUE}}
46}
47
48void largeAdjustmentGE (unsigned a) {
49  if (a-2 >= UINT_MAX-1)
50    clang_analyzer_eval(a == 1 || a == 0); // expected-warning{{TRUE}}
51  else
52    clang_analyzer_eval(a > 1); // expected-warning{{TRUE}}
53}
54
55void largeAdjustmentLT (unsigned a) {
56  if (a+2 < 1)
57    clang_analyzer_eval(a == UINT_MAX-1); // expected-warning{{TRUE}}
58  else
59    clang_analyzer_eval(a != UINT_MAX-1); // expected-warning{{TRUE}}
60}
61
62void largeAdjustmentLE (unsigned a) {
63  if (a+2 <= 1)
64    clang_analyzer_eval(a == UINT_MAX-1 || a == UINT_MAX); // expected-warning{{TRUE}}
65  else
66    clang_analyzer_eval(a < UINT_MAX-1); // expected-warning{{TRUE}}
67}
68
69
70// Test the nine cases in RangeConstraintManager's pinning logic.
71// For out-of-range tautologies, it may be the negation that actually
72// triggers the case in question.
73void mixedComparisons1(signed char a) {
74  // Case 1: The range is entirely below the symbol's range.
75  int min = INT_MIN;
76
77  clang_analyzer_eval((a - 2) >= (min + 5LL)); // expected-warning{{TRUE}}
78
79  clang_analyzer_eval(a == 0); // expected-warning{{UNKNOWN}}
80  clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
81  clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
82}
83
84void mixedComparisons2(signed char a) {
85  // Case 2: Only the lower end of the range is outside.
86  clang_analyzer_eval((a - 5) < (-0x81LL)); // expected-warning{{UNKNOWN}}
87
88  if ((a - 5) < (-0x81LL)) {
89    clang_analyzer_eval(a == 0); // expected-warning{{FALSE}}
90    clang_analyzer_eval(a == 0x7F); // expected-warning{{FALSE}}
91    clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
92  }
93}
94
95void mixedComparisons3(signed char a) {
96  // Case 3: The entire symbol range is covered.
97  clang_analyzer_eval((a - 0x200) < -0x100LL); // expected-warning{{TRUE}}
98
99  clang_analyzer_eval(a == 0); // expected-warning{{UNKNOWN}}
100  clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
101  clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
102}
103
104void mixedComparisons4(signed char a) {
105  // Case 4: The range wraps around, but the lower wrap is out-of-range.
106  clang_analyzer_eval((a - 5) > 0LL); // expected-warning{{UNKNOWN}}
107
108  if ((a - 5) > 0LL) {
109    clang_analyzer_eval(a == 0); // expected-warning{{FALSE}}
110    clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
111    clang_analyzer_eval(a == -0x80); // expected-warning{{FALSE}}
112  }
113}
114
115void mixedComparisons5(signed char a) {
116  // Case 5: The range is inside and may or may not wrap.
117  clang_analyzer_eval((a + 5) == 0LL); // expected-warning{{UNKNOWN}}
118
119  if ((a + 5) == 0LL) {
120    clang_analyzer_eval(a == 0); // expected-warning{{FALSE}}
121    clang_analyzer_eval(a == 0x7F); // expected-warning{{FALSE}}
122    clang_analyzer_eval(a == -0x80); // expected-warning{{FALSE}}
123  } else {
124    clang_analyzer_eval(a == 0); // expected-warning{{UNKNOWN}}
125    clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
126    clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
127  }
128}
129
130void mixedComparisons6(signed char a) {
131  // Case 6: Only the upper end of the range is outside.
132  clang_analyzer_eval((a + 5) > 0x81LL); // expected-warning{{UNKNOWN}}
133
134  if ((a + 5) > 0x81LL) {
135    clang_analyzer_eval(a == 0); // expected-warning{{FALSE}}
136    clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
137    clang_analyzer_eval(a == -0x80); // expected-warning{{FALSE}}
138  }
139}
140
141void mixedComparisons7(signed char a) {
142  // Case 7: The range wraps around but is entirely outside the symbol's range.
143  int min = INT_MIN;
144
145  clang_analyzer_eval((a + 2) >= (min + 5LL)); // expected-warning{{TRUE}}
146
147  clang_analyzer_eval(a == 0); // expected-warning{{UNKNOWN}}
148  clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
149  clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
150}
151
152void mixedComparisons8(signed char a) {
153  // Case 8: The range wraps, but the upper wrap is out of range.
154  clang_analyzer_eval((a + 5) < 0LL); // expected-warning{{UNKNOWN}}
155
156  if ((a + 5) < 0LL) {
157    clang_analyzer_eval(a == 0); // expected-warning{{FALSE}}
158    clang_analyzer_eval(a == 0x7F); // expected-warning{{FALSE}}
159    clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
160  }
161}
162
163void mixedComparisons9(signed char a) {
164  // Case 9: The range is entirely above the symbol's range.
165  int max = INT_MAX;
166
167  clang_analyzer_eval((a + 2) <= (max - 5LL)); // expected-warning{{TRUE}}
168
169  clang_analyzer_eval(a == 0); // expected-warning{{UNKNOWN}}
170  clang_analyzer_eval(a == 0x7F); // expected-warning{{UNKNOWN}}
171  clang_analyzer_eval(a == -0x80); // expected-warning{{UNKNOWN}}
172}
173