C++: Make 'getInstructionConvertedResultExpression' equivalent in C and C++.

Author: MathiasVP

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/IRConstruction.qll

@@ -171,6 +171,20 @@ module Raw {
       // forwarded the result of another translated expression.
       instruction = translatedExpr.getInstruction(_)
     )
+    or
+    // Consider the snippet `if(x) { ... }` where `x` is an integer.
+    // In C++ there is a `BoolConversion` conversion on `x` which generates a
+    // `CompareNEInstruction` whose `getInstructionUnconvertedResultExpression`
+    // is the `BoolConversion`. Thus, calling `getInstructionConvertedResultExpression` on
+    // the `CompareNEInstruction` gives `x` in C++ code.
+    // However, in C there is no such conversion to return. So instead we have
+    // to map the result of `getInstructionConvertedResultExpression` on
+    // the `CompareNEInstruction` to `x` manually.
+    exists(TranslatedValueCondition translatedValueCondition |
+      translatedValueCondition = getTranslatedCondition(result) and
+      translatedValueCondition.shouldGenerateCompareNE() and
+      instruction = translatedValueCondition.getInstruction(ValueConditionCompareTag())
+    )
   }
 
   cached

cpp/ql/test/library-tests/controlflow/guards-ir/tests.expected

@@ -20,12 +20,21 @@ astGuards
 | test.c:109:9:109:14 | ... == ... |
 | test.c:109:9:109:23 | ... \|\| ... |
 | test.c:109:19:109:23 | ... < ... |
+| test.c:126:7:126:7 | 1 |
+| test.c:126:7:126:28 | ... && ... |
+| test.c:126:12:126:26 | call to test3_condition |
+| test.c:131:7:131:7 | b |
+| test.c:137:7:137:7 | 0 |
 | test.c:146:7:146:8 | ! ... |
+| test.c:152:10:152:10 | x |
+| test.c:152:10:152:15 | ... && ... |
+| test.c:152:15:152:15 | y |
 | test.c:156:9:156:19 | ... == ... |
 | test.c:159:9:159:19 | ... == ... |
 | test.c:162:9:162:18 | ... < ... |
 | test.c:165:9:165:18 | ... < ... |
 | test.c:175:13:175:32 | ... == ... |
+| test.c:181:9:181:9 | x |
 | test.cpp:18:8:18:10 | call to get |
 | test.cpp:31:7:31:13 | ... == ... |
 | test.cpp:42:13:42:20 | call to getABool |
@@ -184,10 +193,29 @@ astGuardsCompare
 | 109 | y < 0+0 when ... < ... is true |
 | 109 | y >= 0+0 when ... < ... is false |
 | 109 | y >= 0+0 when ... \|\| ... is false |
+<<<<<<< HEAD
 | 146 | ! ... != 0 when ! ... is true |
 | 146 | ! ... == 0 when ! ... is false |
+=======
+| 126 | 1 != 0 when 1 is true |
+| 126 | 1 != 0 when ... && ... is true |
+| 126 | 1 == 0 when 1 is false |
+| 126 | call to test3_condition != 0 when ... && ... is true |
+| 126 | call to test3_condition != 0 when call to test3_condition is true |
+| 126 | call to test3_condition == 0 when call to test3_condition is false |
+| 131 | b != 0 when b is true |
+| 131 | b == 0 when b is false |
+| 137 | 0 != 0 when 0 is true |
+| 137 | 0 == 0 when 0 is false |
+>>>>>>> c9b478b6b7 (C++: Make 'getInstructionConvertedResultExpression' equivalent in C and C++.)
 | 146 | x != 0 when ! ... is false |
 | 146 | x == 0 when ! ... is true |
+| 152 | x != 0 when ... && ... is true |
+| 152 | x != 0 when x is true |
+| 152 | x == 0 when x is false |
+| 152 | y != 0 when ... && ... is true |
+| 152 | y != 0 when y is true |
+| 152 | y == 0 when y is false |
 | 156 | ... + ... != x+0 when ... == ... is false |
 | 156 | ... + ... == x+0 when ... == ... is true |
 | 156 | ... == ... != 0 when ... == ... is true |
@@ -236,6 +264,8 @@ astGuardsCompare
 | 175 | call to foo != 0+0 when ... == ... is false |
 | 175 | call to foo == 0 when ... == ... is true |
 | 175 | call to foo == 0+0 when ... == ... is true |
+| 181 | x != 0 when x is true |
+| 181 | x == 0 when x is false |
 astGuardsControl
 | test.c:7:9:7:13 | ... > ... | false | 10 | 11 |
 | test.c:7:9:7:13 | ... > ... | true | 7 | 9 |
@@ -307,13 +337,29 @@ astGuardsControl
 | test.c:109:9:109:14 | ... == ... | false | 113 | 113 |
 | test.c:109:9:109:23 | ... \|\| ... | false | 113 | 113 |
 | test.c:109:19:109:23 | ... < ... | false | 113 | 113 |
+| test.c:126:7:126:7 | 1 | true | 126 | 126 |
+| test.c:126:7:126:7 | 1 | true | 126 | 128 |
+| test.c:126:7:126:7 | 1 | true | 131 | 131 |
+| test.c:126:7:126:7 | 1 | true | 131 | 132 |
+| test.c:126:7:126:7 | 1 | true | 134 | 123 |
+| test.c:126:7:126:28 | ... && ... | true | 126 | 128 |
+| test.c:126:12:126:26 | call to test3_condition | true | 126 | 128 |
+| test.c:131:7:131:7 | b | true | 131 | 132 |
+| test.c:137:7:137:7 | 0 | false | 142 | 136 |
 | test.c:146:7:146:8 | ! ... | true | 146 | 147 |
+| test.c:152:10:152:10 | x | true | 151 | 152 |
+| test.c:152:10:152:10 | x | true | 152 | 152 |
+| test.c:152:10:152:15 | ... && ... | true | 151 | 152 |
+| test.c:152:15:152:15 | y | true | 151 | 152 |
 | test.c:156:9:156:19 | ... == ... | true | 156 | 157 |
 | test.c:159:9:159:19 | ... == ... | true | 159 | 160 |
 | test.c:162:9:162:18 | ... < ... | true | 162 | 163 |
 | test.c:165:9:165:18 | ... < ... | true | 165 | 166 |
 | test.c:175:13:175:32 | ... == ... | false | 175 | 175 |
 | test.c:175:13:175:32 | ... == ... | true | 175 | 175 |
+| test.c:181:9:181:9 | x | false | 183 | 184 |
+| test.c:181:9:181:9 | x | true | 181 | 182 |
+| test.c:181:9:181:9 | x | true | 186 | 180 |
 | test.cpp:18:8:18:10 | call to get | true | 19 | 19 |
 | test.cpp:31:7:31:13 | ... == ... | false | 30 | 30 |
 | test.cpp:31:7:31:13 | ... == ... | false | 34 | 34 |
@@ -611,6 +657,7 @@ astGuardsEnsure_const
 | test.c:109:9:109:14 | ... == ... | test.c:109:9:109:14 | ... == ... | == | 0 | 109 | 109 |
 | test.c:109:9:109:14 | ... == ... | test.c:109:9:109:14 | ... == ... | == | 0 | 113 | 113 |
 | test.c:109:9:109:23 | ... \|\| ... | test.c:109:9:109:9 | x | != | 0 | 113 | 113 |
+<<<<<<< HEAD
 | test.c:109:9:109:23 | ... \|\| ... | test.c:109:9:109:14 | ... == ... | == | 0 | 113 | 113 |
 | test.c:109:9:109:23 | ... \|\| ... | test.c:109:19:109:23 | ... < ... | == | 0 | 113 | 113 |
 | test.c:109:19:109:23 | ... < ... | test.c:109:19:109:23 | ... < ... | == | 0 | 113 | 113 |
@@ -624,6 +671,29 @@ astGuardsEnsure_const
 | test.c:175:13:175:32 | ... == ... | test.c:175:13:175:15 | call to foo | == | 0 | 175 | 175 |
 | test.c:175:13:175:32 | ... == ... | test.c:175:13:175:32 | ... == ... | != | 0 | 175 | 175 |
 | test.c:175:13:175:32 | ... == ... | test.c:175:13:175:32 | ... == ... | == | 0 | 175 | 175 |
+=======
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 126 | 126 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 126 | 128 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 131 | 131 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 131 | 132 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 134 | 123 |
+| test.c:126:7:126:28 | ... && ... | test.c:126:7:126:7 | 1 | != | 0 | 126 | 128 |
+| test.c:126:7:126:28 | ... && ... | test.c:126:12:126:26 | call to test3_condition | != | 0 | 126 | 128 |
+| test.c:126:12:126:26 | call to test3_condition | test.c:126:12:126:26 | call to test3_condition | != | 0 | 126 | 128 |
+| test.c:131:7:131:7 | b | test.c:131:7:131:7 | b | != | 0 | 131 | 132 |
+| test.c:137:7:137:7 | 0 | test.c:137:7:137:7 | 0 | == | 0 | 142 | 136 |
+| test.c:146:7:146:8 | ! ... | test.c:146:8:146:8 | x | == | 0 | 146 | 147 |
+| test.c:152:10:152:10 | x | test.c:152:10:152:10 | x | != | 0 | 151 | 152 |
+| test.c:152:10:152:10 | x | test.c:152:10:152:10 | x | != | 0 | 152 | 152 |
+| test.c:152:10:152:15 | ... && ... | test.c:152:10:152:10 | x | != | 0 | 151 | 152 |
+| test.c:152:10:152:15 | ... && ... | test.c:152:15:152:15 | y | != | 0 | 151 | 152 |
+| test.c:152:15:152:15 | y | test.c:152:15:152:15 | y | != | 0 | 151 | 152 |
+| test.c:175:13:175:32 | ... == ... | test.c:175:13:175:15 | call to foo | != | 0 | 175 | 175 |
+| test.c:175:13:175:32 | ... == ... | test.c:175:13:175:15 | call to foo | == | 0 | 175 | 175 |
+| test.c:181:9:181:9 | x | test.c:181:9:181:9 | x | != | 0 | 181 | 182 |
+| test.c:181:9:181:9 | x | test.c:181:9:181:9 | x | != | 0 | 186 | 180 |
+| test.c:181:9:181:9 | x | test.c:181:9:181:9 | x | == | 0 | 183 | 184 |
+>>>>>>> c9b478b6b7 (C++: Make 'getInstructionConvertedResultExpression' equivalent in C and C++.)
 | test.cpp:18:8:18:10 | call to get | test.cpp:18:8:18:10 | call to get | != | 0 | 19 | 19 |
 | test.cpp:31:7:31:13 | ... == ... | test.cpp:31:7:31:7 | x | != | -1 | 30 | 30 |
 | test.cpp:31:7:31:13 | ... == ... | test.cpp:31:7:31:7 | x | != | -1 | 34 | 34 |

cpp/ql/test/library-tests/controlflow/guards/Guards.expected

@@ -19,8 +19,15 @@
 | test.c:109:9:109:14 | ... == ... |
 | test.c:109:9:109:23 | ... \|\| ... |
 | test.c:109:19:109:23 | ... < ... |
+| test.c:126:7:126:7 | 1 |
+| test.c:126:7:126:28 | ... && ... |
+| test.c:126:12:126:26 | call to test3_condition |
+| test.c:131:7:131:7 | b |
+| test.c:137:7:137:7 | 0 |
 | test.c:146:7:146:8 | ! ... |
+| test.c:152:8:152:8 | p |
 | test.c:158:8:158:9 | ! ... |
+| test.c:164:8:164:8 | s |
 | test.c:170:8:170:9 | ! ... |
 | test.cpp:18:8:18:10 | call to get |
 | test.cpp:31:7:31:13 | ... == ... |

cpp/ql/test/library-tests/controlflow/guards/GuardsCompare.expected

@@ -208,6 +208,12 @@
 | 125 | call to safe != 0 when ! ... is false |
 | 125 | call to safe != 0 when call to safe is true |
 | 125 | call to safe == 0 when call to safe is false |
+| 126 | 1 != 0 when 1 is true |
+| 126 | 1 != 0 when ... && ... is true |
+| 126 | 1 == 0 when 1 is false |
+| 126 | call to test3_condition != 0 when ... && ... is true |
+| 126 | call to test3_condition != 0 when call to test3_condition is true |
+| 126 | call to test3_condition == 0 when call to test3_condition is false |
 | 131 | ... + ... != a+0 when call to __builtin_expect is false |
 | 131 | ... + ... == a+0 when call to __builtin_expect is true |
 | 131 | ... == ... != 0 when call to __builtin_expect is true |
@@ -216,7 +222,9 @@
 | 131 | a != b+42 when call to __builtin_expect is false |
 | 131 | a == ... + ...+0 when call to __builtin_expect is true |
 | 131 | a == b+42 when call to __builtin_expect is true |
+| 131 | b != 0 when b is true |
 | 131 | b != a+-42 when call to __builtin_expect is false |
+| 131 | b == 0 when b is false |
 | 131 | b == a+-42 when call to __builtin_expect is true |
 | 131 | call to __builtin_expect != 0 when call to __builtin_expect is true |
 | 131 | call to __builtin_expect == 0 when call to __builtin_expect is false |
@@ -232,6 +240,8 @@
 | 135 | b == a+-42 when call to __builtin_expect is false |
 | 135 | call to __builtin_expect != 0 when call to __builtin_expect is true |
 | 135 | call to __builtin_expect == 0 when call to __builtin_expect is false |
+| 137 | 0 != 0 when 0 is true |
+| 137 | 0 == 0 when 0 is false |
 | 141 | 42 != a+0 when call to __builtin_expect is false |
 | 141 | 42 == a+0 when call to __builtin_expect is true |
 | 141 | ... == ... != 0 when call to __builtin_expect is true |
@@ -256,10 +266,14 @@
 | 146 | ! ... == 0 when ! ... is false |
 | 146 | x != 0 when ! ... is false |
 | 146 | x == 0 when ! ... is true |
+| 152 | p != 0 when p is true |
+| 152 | p == 0 when p is false |
 | 158 | ! ... != 0 when ! ... is true |
 | 158 | ! ... == 0 when ! ... is false |
 | 158 | p != 0 when ! ... is false |
 | 158 | p == 0 when ! ... is true |
+| 164 | s != 0 when s is true |
+| 164 | s == 0 when s is false |
 | 170 | ! ... != 0 when ! ... is true |
 | 170 | ! ... == 0 when ! ... is false |
 | 170 | s != 0 when ! ... is false |

cpp/ql/test/library-tests/controlflow/guards/GuardsControl.expected

@@ -68,8 +68,19 @@
 | test.c:109:9:109:14 | ... == ... | false | 113 | 113 |
 | test.c:109:9:109:23 | ... \|\| ... | false | 113 | 113 |
 | test.c:109:19:109:23 | ... < ... | false | 113 | 113 |
+| test.c:126:7:126:7 | 1 | true | 126 | 126 |
+| test.c:126:7:126:7 | 1 | true | 126 | 128 |
+| test.c:126:7:126:7 | 1 | true | 131 | 131 |
+| test.c:126:7:126:7 | 1 | true | 131 | 132 |
+| test.c:126:7:126:7 | 1 | true | 134 | 123 |
+| test.c:126:7:126:28 | ... && ... | true | 126 | 128 |
+| test.c:126:12:126:26 | call to test3_condition | true | 126 | 128 |
+| test.c:131:7:131:7 | b | true | 131 | 132 |
+| test.c:137:7:137:7 | 0 | false | 142 | 136 |
 | test.c:146:7:146:8 | ! ... | true | 146 | 147 |
+| test.c:152:8:152:8 | p | true | 152 | 154 |
 | test.c:158:8:158:9 | ! ... | true | 158 | 160 |
+| test.c:164:8:164:8 | s | true | 164 | 166 |
 | test.c:170:8:170:9 | ! ... | true | 170 | 172 |
 | test.cpp:18:8:18:10 | call to get | true | 19 | 19 |
 | test.cpp:31:7:31:13 | ... == ... | false | 30 | 30 |

cpp/ql/test/library-tests/controlflow/guards/GuardsEnsure.expected

@@ -340,10 +340,22 @@ unary
 | test.c:109:9:109:23 | ... \|\| ... | test.c:109:19:109:23 | ... < ... | == | 0 | 113 | 113 |
 | test.c:109:19:109:23 | ... < ... | test.c:109:19:109:19 | y | >= | 0 | 113 | 113 |
 | test.c:109:19:109:23 | ... < ... | test.c:109:19:109:23 | ... < ... | == | 0 | 113 | 113 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 126 | 126 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 126 | 128 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 131 | 131 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 131 | 132 |
+| test.c:126:7:126:7 | 1 | test.c:126:7:126:7 | 1 | != | 0 | 134 | 123 |
+| test.c:126:7:126:28 | ... && ... | test.c:126:7:126:7 | 1 | != | 0 | 126 | 128 |
+| test.c:126:7:126:28 | ... && ... | test.c:126:12:126:26 | call to test3_condition | != | 0 | 126 | 128 |
+| test.c:126:12:126:26 | call to test3_condition | test.c:126:12:126:26 | call to test3_condition | != | 0 | 126 | 128 |
+| test.c:131:7:131:7 | b | test.c:131:7:131:7 | b | != | 0 | 131 | 132 |
+| test.c:137:7:137:7 | 0 | test.c:137:7:137:7 | 0 | == | 0 | 142 | 136 |
 | test.c:146:7:146:8 | ! ... | test.c:146:7:146:8 | ! ... | != | 0 | 146 | 147 |
 | test.c:146:7:146:8 | ! ... | test.c:146:8:146:8 | x | == | 0 | 146 | 147 |
+| test.c:152:8:152:8 | p | test.c:152:8:152:8 | p | != | 0 | 152 | 154 |
 | test.c:158:8:158:9 | ! ... | test.c:158:8:158:9 | ! ... | != | 0 | 158 | 160 |
 | test.c:158:8:158:9 | ! ... | test.c:158:9:158:9 | p | == | 0 | 158 | 160 |
+| test.c:164:8:164:8 | s | test.c:164:8:164:8 | s | != | 0 | 164 | 166 |
 | test.c:170:8:170:9 | ! ... | test.c:170:8:170:9 | ! ... | != | 0 | 170 | 172 |
 | test.c:170:8:170:9 | ! ... | test.c:170:9:170:9 | s | == | 0 | 170 | 172 |
 | test.cpp:18:8:18:10 | call to get | test.cpp:18:8:18:10 | call to get | != | 0 | 19 | 19 |