Removes the IR consistency checks for conflated memory and marks
instructions that have a conflated result with a percent sign (%)
instead. This avoids reimplementing part of the alias analysis logic
in the consistency check.
This fixes the IR generation for member accesses where the qualifier is a prvalue that is _not_ the load of a `TemporaryObjectExpr`. We synthesize a temporary variable during IR generation instead. It fits into the IR construction code at the same spot as `TranslatedLoad`, since it's basically the opposite of `TranslatedLoad` (prvalue->glvalue instead of vice versa). Note that array prvalues require special treatment.
This fixes some consistency errors in the `syntax-zoo`. It introduces three new ones in `dataflow-ir-consistency.expected`, but those are along the same lines as tons of existing failures.
For historical reasons, the extractor marks the temporary object expression used as the qualifier of a member access as a prvalue(load), even though the current C++ standard says that the temporary object materialization results in a glvalue. Added some special handling to ignore the load for both field accesses and member function calls.
This fixes all of the consistency failures in our regular tests, and all of the related failures in `syntax-zoo` other than the ones that deal with pointers-to-member, which aren't really supported yet anyway.
There was unfortunately a semantic merge conflict between #3419 and
#3587 that caused a performance regression on (at least) OpenJDK.
This reverts commit 982fb38807, reversing
changes made to b841cacb83.
Some of our IR consistency failure query predicates already produced results in the schema as an `@kind problem` query, including `$@` replacements for the enclosing `IRFunction` to make it easier to figure out which function to dump when debugging. This change moves the rest of the query predicates in `IRConsistency.qll` to do the same. In addition, it wraps each call to `getEnclosingIRFunction()` to return an `OptionalIRFunction`, which can be either a real `IRFunction` or a placeholder in case `getEnclosingIRFunction()` returned no results. This exposes a couple new consistency failures in `syntax-zoo`, which will be fixed in a subsequent commit.
This change also deals with consistency failures when the enclosing `IRFunction` has more than one `Function` or `Location`. For multiple `Function`s, we concatenate the function names. For multiple `Location`s, we pick the first one in lexicographical order. This changes the number of results produced in the existing tests, but does't change the actual number of problems.
The conflicts came from how `this` is now a parameter but not a
`Parameter` on `master`.
Conflicts:
cpp/ql/src/semmle/code/cpp/ir/dataflow/internal/DataFlowUtil.qll
cpp/ql/test/library-tests/dataflow/DefaultTaintTracking/defaulttainttracking.cpp
cpp/ql/test/library-tests/dataflow/DefaultTaintTracking/tainted.expected
cpp/ql/test/library-tests/dataflow/DefaultTaintTracking/test_diff.expected
cpp/ql/test/library-tests/dataflow/dataflow-tests/dataflow-ir-consistency.expected
cpp/ql/test/library-tests/dataflow/fields/ir-flow.expected
cpp/ql/test/library-tests/syntax-zoo/dataflow-ir-consistency.expected
