Commit Graph

4 Commits

Author SHA1 Message Date
Balazs Benics 881b6a009f [analyzer][NFC] Re-enable skipped SValTests by relaxing expectations
Some tests were skipped in D114454 to resolve test failures on some
platforms, where the pointers have different bitwidth than expected.
This patch re-enables these tests, by relaxing the requirements on the
types of the SVal.

The issue:
There is no way to reconstruct the type of the `SVal` perfectly
accurately, since there could be multiple types having the required
bitwidth and signedness.
Consider platforms where `int` and `long` have the same bitwidth.
Additionally, we need to be careful about casting a pointer to an
integral representation, because we don't know what smallest integral
type can represent that.

To workaround these issues, I propose enforcing a type that has the
same signedness and bitwidth as the expected type, instead of perfect
equality.

In the `GetLocAsIntType` test, in case of pointer-to-integral casts
I'm using the widest standard integral type (long long) to make sure
that the pointer can be represented by the type without losing
precision. This won't affect the test in any meaningful way, since the
type of the `lvalue` remained the same.

In one case, I had to replace `getUIntPtrType()` with `UnsignedLongTy`
because on some platforms `getUIntPtrType()` is different then `long
int`.

In this patch, I also enforce that the tests must compile without
errors, to prevent narrowing conversions in the future.

Reviewed By: stevewan

Differential Revision: https://reviews.llvm.org/D115349
2022-01-19 15:16:18 +01:00
Steven Wan 9c4d194f44 [analyzer]Skip unstable CSA tests failing on several platforms
Clang static analyzer uses bitwidth to infer the integer value type, that is, any 32-bit integer is considered of type `int`, and any 64-bit integer is considered of type `long`. This isn't always true, for instance, in ILP32 (e.g., 32-bit AIX), 32-bit could be `long`, and in LP64 (e.g., 64-bit wasm64), 64-bit could be `long long`.

Reviewed By: steakhal

Differential Revision: https://reviews.llvm.org/D114454
2021-12-02 18:30:14 -05:00
Valeriy Savchenko b2842298ce [analyzer] Fix SValTest for LocAsInt test 2021-06-29 13:01:41 +03:00
Valeriy Savchenko 159024ce23 [analyzer] Implement getType for SVal
This commit adds a function to the top-class of SVal hierarchy to
provide type information about the value.  That can be extremely
useful when this is the only piece of information that the user is
actually caring about.

Additionally, this commit introduces a testing framework for writing
unit-tests for symbolic values.

Differential Revision: https://reviews.llvm.org/D104550
2021-06-29 12:11:19 +03:00