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[TG-2717] Generic inheritance with pointer replacement #2051

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Merged
merged 3 commits into from
Apr 17, 2018

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majakusber
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@majakusber majakusber commented Apr 12, 2018

When initiliazing a pointer and it is replaced by a different pointer (due to inheritance) we make sure that the generic parameter specialization map is updated too. For example, if we see a pointer to Interface<Integer> and there exists a class A<T> implements Interface<T> then we will be replacing the pointer with a pointer to A<Integer>. This PR makes sure that the generic type A::T is mapped to Integer.

Since CBMC does not construct replacement pointers, this change has no effect in CBMC itself (hence no unit tests or regression tests). The change is utilized in test generator: https://github.com/diffblue/test-gen/pull/1695.

{
for(const auto &b : bases())
{
if(to_symbol_type(b.type()).get(ID_identifier) == id)
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Use get_identifier() instead of get(ID_identifier). Looking at the code, has_base should actually also be amended in this way. With that looking-at-code done, I'm wondering whether this duplicate iteration over bases is a good idea? Can get_base actually be implemented by just doing the loop and has_base by doing return bool(get_base(id));?

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Or rather get_base(id).has_value()?

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Sure, that's likely the proper way of doing it!

@@ -766,6 +766,13 @@ void java_object_factoryt::gen_nondet_pointer_init(
// for java types, technical debt TG-2707
if(!equal_java_types(replacement_pointer_type, pointer_type))
{
// update generic_parameter_specialization_map if needed
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Consider elaborating this comment with an example. E.g.:

// if replacement_pointer_type is Implementation<T> implements I<T, Float>
// then this inserts pairs:
//   I::T -> Implementation::T, 
//   I::U -> java.lang.Float

Assuming my understanding is correct?

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Not quite. Here is an example of what happens here:

  1. Assume we see a pointer to I<Integer>.
  2. convert_pointer_type finds a class Impl<T,U> implements I<T> and builds a replacement pointer Impl<Integer, U> (note that CBMC does not build these replacement pointers, only test generator).
  3. Below we simply input the pairs for the replacement pointer to the map (nothing inheritance-specific): Impl::T -> Integer (the second parameter is unspecialized).

/// in the vector of generic types.
/// \param type The type we are looking for.
/// \return The index of the type in the vector of generic types.
optionalt<size_t> generic_type(const reference_typet &type) const
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Is there a reason to return an index (not yet looked at TG PR)? It seems like this code at least would be simpler to just return a optionalt<reference_typet>

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I will need the index later on in test generator so I thought a separate function for it would be useful. Would changing the name of the function make it more clear?

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Just a minor readability comment, to fix if you have time.

{
const size_t &index =
std::find(generic_types().begin(), generic_types().end(), type) -
generic_types().begin();
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NIT: I think this would be easier to read if the result of std::find was assigned to a temporary variable and checked against generic_types().end() in the if statement below, with the subtraction only done inside the if statement.

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@thk123 Ready for re-review.

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thk123 commented Apr 16, 2018

LGTM - just waiting on TG pointer approval

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@thk123 TG pointer passed CI, I rebased and squashed this PR.

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Looks like mostly transient problems, but if you could fix the clang format error then will merge once CI goes green

svorenova added 3 commits April 17, 2018 09:29
When initiliazing a pointer and it is replaced by a different pointer due to inheritence make sure that the generic parameter
specialization map is updated too.
These will be used in test generator to convert generic pointer types.
Now simply calls a function for base retrieval
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majakusber commented Apr 17, 2018

Fixed, waiting for CI.

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@tautschnig Just noticed we need one more review for this from a code owner, would you mind taking a look at it again?

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LGTM

@thk123 thk123 merged commit 00b9bf6 into diffblue:develop Apr 17, 2018
@majakusber majakusber deleted the generics_tg2717 branch April 18, 2018 16:27
smowton added a commit to smowton/cbmc that referenced this pull request May 9, 2018
ad62682 Merge pull request diffblue#2071 from thk123/refactor/split-string-unit-tests
fc8ba88 Revert to aborting precondition for function inputs
3e2ab6f Merge pull request diffblue#2080 from diffblue/java-bytecode-dependency
6ff1eec cbmc: remove dependency on java_bytecode
0bff19b Merge pull request diffblue#2049 from karkhaz/kk-factor-goto-model-processing
79e3b25 Merge pull request diffblue#2084 from tautschnig/has_subtype-test
cd45b0b Test has_subtype on recursive data types
85ac315 Merge pull request diffblue#2082 from thomasspriggs/default_dstring_hash
28c2e8b Merge pull request diffblue#2065 from tautschnig/be-constructor
afa6023 Merge pull request diffblue#2061 from tautschnig/simplify-extractbits
014d151 Factor out getting & processing goto-model
06b3adc Merge pull request diffblue#2077 from peterschrammel/stable-tmp-var-names
0b3170d Stabilize clinit wrapper function type parameters
3cd8bf4 Temporary vars tests for goto-diff
9f0626c  Prefix temporary var names with function id
ca678aa More permissive regression tests regarding tmp var suffixes
47951ca Merge pull request diffblue#2079 from romainbrenguier/bugfix/has-subtype-recursion
dd73b1a Specify default hash function of `dstringt` to STL.
fe8e589 Avoid infinite recursion in has_subtype
00b9bf6 Merge pull request diffblue#2051 from svorenova/generics_tg2717
cd4bfc3 Merge pull request diffblue#2078 from romainbrenguier/bool-literal-in-while-loop
67ea889 Use bool literal in while loop
d229ad9 Merge pull request diffblue#2056 from diffblue/fix-regression-cbmc-memcpy1
506faf0 Refactor a function for base existence
617d388 Utility functions for generic types
c07e6ca Update generic specialization map when replacing pointers
ed26d0a Merge pull request diffblue#2058 from peterschrammel/stable-disjuncts
b663734 Simplify extractbits(concatenation(...))
b091560 Typing and refactoring of simplify_extractbits
49ad1bd Merge pull request diffblue#974 from tautschnig/fix-assert-encoding
16e9599 Merge pull request diffblue#2063 from tautschnig/has-subtype
950f58b Merge pull request diffblue#2060 from tautschnig/opt-local-map
4222a94 Regression tests for unstable instanceof and virtual method disjuncts
b44589e Make disjuncts in instanceof removal independent of class loading
3afff86 Make disjuncts in virtual method removal independent of class loading
a385d9b Allowed split_string to be used on whitespace if not also trying to strip
fe4a642 Merge pull request diffblue#2062 from tautschnig/no-has-deref
145f474 Adding tests for empty string edge cases
07009d4 Refactored test to run all combinations
252c24c Migrate old string utils unit tests
e87edbf Removing wrong elements from the make file
b165c52 make test work on 32-bit Linux
b804570 Merge pull request diffblue#2048 from JohnDumbell/improvement/adding_null_object_id
61f14d8 Merge pull request diffblue#1962 from owen-jones-diffblue/owen-jones-diffblue/simplify-replace-java-nondet
fdee7e8 Merge pull request diffblue#2059 from tautschnig/generalise-test
4625cc5 Extend global has_subexpr to take a predicate as has_subtype does
e9ebd59 has_subtype(type, pred, ns) to search for contained type matching pred
1f1f67f Merge pull request diffblue#1889 from hannes-steffenhagen-diffblue/develop-feature_generate_function_bodies
048c188 Add unit test for java_replace_nondet
0fe48c9 Make remove_java_nondet work before remove_returns
bcc4dc4 Use byte_extract_exprt constructor
a1814a3 Get rid of thin (and duplicate) has_dereference wrapper
4122a28 Test to demonstrate assert bug on alpine
d44bfd3 Also simplify assert structure found on alpine linux
c5cde18 Do not generate redundant if statements in assert expansions
4fb0603 Make is_skip publicly available and use constant argument
5832ffd Negative numbers should also pass the test
3c23b28 Consistently disable simplify_exprt::local_replace_map
da63652 Merge pull request diffblue#2054 from romainbrenguier/bugfix/clear-equations
d77f6a2 Merge pull request diffblue#1831 from NathanJPhillips/feature/class-annotations
60c8296 Clear string_refinement equations (not dependencies)
314ed53 Correcting the value of ID_null_object
751a882 Factor out default CBMC options to static method
6f24009 Can now test for an option being set in optionst
9a8d937 Add to_annotated_type and enable type_checked_cast for annotated_typet
ca77b4e Add test for added annotations
b06a27d Introduce abstract qualifierst base class
e6fb3bf Pretty printing of java_class_typet
e22b95b Fix spurious virtual function related keywords
3ac6d17 Add type_dynamic_cast and friends for java_class_typet
ce1f4d2 Add annotations to java_class_typet, its methods and fields
f84753d Merge pull request diffblue#2042 from hannes-steffenhagen-diffblue/add_deprecate_macro
7a38669 Merge pull request diffblue#2017 from NathanJPhillips/feature/overlay-classes
75a4aec Revert "the deprecation will need to wait until codebase is clean"
67735b5 Disable deprecation warnings by default
0764f77 Merge pull request diffblue#2036 from romainbrenguier/id_array_list
690b606 Merge pull request diffblue#2039 from peterschrammel/fix-duplicate-msg-json-ui
bba17d9 the deprecation will need to wait until codebase is clean
822c757 Regression test for redundant JSON message output
de0644d Only force end of previous message if there actually is one.
5a637bf Merge pull request diffblue#2037 from hannes-steffenhagen-diffblue/add_deprecate_macro
bff456a Merge pull request diffblue#2040 from tautschnig/remove-swp
87ebe90 Remove vim temp file
228c019 Fix duplicate message output in json-ui
0a2c43e Add DEPRECATED to functions documented as \deprecated
47f4b35 interval_sparse_arrayt constructor from array-list
026c4ca Declare an array_list_exprt class
50a2696 Define ID_array_list
513b67a Merge pull request diffblue#2038 from romainbrenguier/bugfix/assign-at-malloc-site
c207106 Test with array of strings
60183a3 Assign string at malloc site
116fffd Add DEPRECATED macro to mark deprecated functions and variables
7952f2c Add option to generate function body to goto-instrument
3d4183a Add ability to overlay classes with new definitions of existing methods
dbc2f71 Improve code and error message in infer_opaque_type_fields
7c0ea4d Tidied up java_class_loader_limitt

git-subtree-dir: cbmc
git-subtree-split: ad62682
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5 participants