Skip to content

C++: Fix handling of unreached instructions in IRGuards #15021

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Dec 6, 2023
Merged

C++: Fix handling of unreached instructions in IRGuards #15021

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
d6e30cd
C++: Add test showing unreachable instructions give spurious blocks i…
jketema Dec 6, 2023
4390e4c
C++: Fix handling of unreached instructions in IRGuards
jketema Dec 6, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 3 additions & 0 deletions cpp/ql/lib/semmle/code/cpp/controlflow/IRGuards.qll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -223,6 +223,9 @@ private class GuardConditionFromIR extends GuardCondition {
or
instr = tce.getInstruction(ConditionValueFalseTempAddressTag())
)
or
// Exclude unreached instructions, as their AST is the whole function and not a block.
instr instanceof UnreachedInstruction
}
}

Expand Down
10 changes: 10 additions & 0 deletions cpp/ql/test/library-tests/controlflow/guards-ir/test.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -174,3 +174,13 @@ int ternary_test(const char *path, int mode)
{
return (foo(path, mode) == 0 ? 1 : 0);
}

void abort(void);

int abort_test(int x) {
if (x) {
x += 1;
} else {
abort();
}
}
7 changes: 7 additions & 0 deletions cpp/ql/test/library-tests/controlflow/guards-ir/tests.expected
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,7 @@ astGuards
| 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 |
Expand Down Expand Up @@ -255,6 +256,9 @@ astGuardsControl
| 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 |
Expand Down Expand Up @@ -470,6 +474,7 @@ irGuards
| test.c:162:9:162:18 | CompareLT: ... < ... |
| test.c:165:9:165:18 | CompareLT: ... < ... |
| test.c:175:13:175:32 | CompareEQ: ... == ... |
| test.c:181:9:181:9 | Load: x |
| test.cpp:18:8:18:12 | CompareNE: (bool)... |
| test.cpp:31:7:31:13 | CompareEQ: ... == ... |
| test.cpp:42:13:42:20 | Call: call to getABool |
Expand Down Expand Up @@ -667,6 +672,8 @@ irGuardsControl
| test.c:165:9:165:18 | CompareLT: ... < ... | true | 165 | 166 |
| test.c:175:13:175:32 | CompareEQ: ... == ... | false | 175 | 175 |
| test.c:175:13:175:32 | CompareEQ: ... == ... | true | 175 | 175 |
| test.c:181:9:181:9 | Load: x | false | 184 | 184 |
| test.c:181:9:181:9 | Load: x | true | 182 | 182 |
| test.cpp:18:8:18:12 | CompareNE: (bool)... | true | 19 | 19 |
| test.cpp:31:7:31:13 | CompareEQ: ... == ... | false | 34 | 34 |
| test.cpp:31:7:31:13 | CompareEQ: ... == ... | true | 30 | 30 |
Expand Down