Commit Graph

20 Commits

Author SHA1 Message Date
Matheus Izvekov 15f3cd6bfc
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could expose a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-27 11:10:54 +02:00
Jonas Devlieghere 888673b6e3
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit 7c51f02eff because it
stills breaks the LLDB tests. This was  re-landed without addressing the
issue or even agreement on how to address the issue. More details and
discussion in https://reviews.llvm.org/D112374.
2022-07-14 21:17:48 -07:00
Matheus Izvekov 7c51f02eff
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could exposed a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-15 04:16:55 +02:00
Jonas Devlieghere 3968936b92
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit bdc6974f92 because it
breaks all the LLDB tests that import the std module.

  import-std-module/array.TestArrayFromStdModule.py
  import-std-module/deque-basic.TestDequeFromStdModule.py
  import-std-module/deque-dbg-info-content.TestDbgInfoContentDequeFromStdModule.py
  import-std-module/forward_list.TestForwardListFromStdModule.py
  import-std-module/forward_list-dbg-info-content.TestDbgInfoContentForwardListFromStdModule.py
  import-std-module/list.TestListFromStdModule.py
  import-std-module/list-dbg-info-content.TestDbgInfoContentListFromStdModule.py
  import-std-module/queue.TestQueueFromStdModule.py
  import-std-module/stack.TestStackFromStdModule.py
  import-std-module/vector.TestVectorFromStdModule.py
  import-std-module/vector-bool.TestVectorBoolFromStdModule.py
  import-std-module/vector-dbg-info-content.TestDbgInfoContentVectorFromStdModule.py
  import-std-module/vector-of-vectors.TestVectorOfVectorsFromStdModule.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45301/
2022-07-13 09:20:30 -07:00
Matheus Izvekov bdc6974f92
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-13 02:10:09 +02:00
Balazs Benics 5ce7050f70 [analyzer] Allow exploded graph dumps in release builds
Historically, exploded graph dumps were disabled in non-debug builds.
It was done so probably because a regular user should not dump the
internal representation of the analyzer anyway and the dump methods
might introduce unnecessary binary size overhead.

It turns out some of the users actually want to dump this.

Note that e.g. `LiveExpressionsDumper`, `LiveVariablesDumper`,
`ControlDependencyTreeDumper` etc. worked previously, and they are
unaffected by this change.
However, `CFGViewer` and `CFGDumper` still won't work for a similar
reason. AFAIK only these two won't work after this change.

Addresses #53873

---

**baseline**

| binary | size | size after strip |
| clang | 103M | 83M |
| clang-tidy | 67M | 54M |

**after this change**

| binary | size | size after strip |
| clang | 103M | 84M |
| clang-tidy | 67M | 54M |

CMake configuration:
```
cmake -S llvm -GNinja -DBUILD_SHARED_LIBS=OFF -DCMAKE_BUILD_TYPE=Release
-DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang
-DLLVM_ENABLE_ASSERTIONS=OFF -DLLVM_USE_LINKER=lld
-DLLVM_ENABLE_DUMP=OFF -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra"
-DLLVM_ENABLE_Z3_SOLVER=ON -DLLVM_TARGETS_TO_BUILD="X86"
```
Built by `clang-14.0.0`.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D124442
2022-05-02 11:42:08 +02:00
Artem Dergachev 2b4f6df917 [analyzer] Fix FieldRegion dumps.
The '->' thing has always been confusing; the actual operation '->'
translates to a pointer dereference together with adding a FieldRegion,
but FieldRegion on its own doesn't imply an additional pointer
dereference.

llvm-svn: 375281
2019-10-18 20:15:39 +00:00
Csaba Dabis 0202c3596c [analyzer] CastValueChecker: Store the dynamic types and casts
Summary:
This patch introduces `DynamicCastInfo` similar to `DynamicTypeInfo` which
is stored in `CastSets` which are storing the dynamic cast informations of
objects based on memory regions. It could be used to store and check the
casts and prevent infeasible paths.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66325

llvm-svn: 369605
2019-08-22 00:20:36 +00:00
Artem Dergachev ed035ff826 [analyzer] exploded-graph-rewriter: Improve source location dumps.
- Correctly display macro expansion and spelling locations.
- Use the same procedure to display location context call site locations.
- Display statement IDs for program points.

llvm-svn: 365861
2019-07-12 02:10:33 +00:00
Artem Dergachev 064c8c689a [analyzer] Fix JSON dumps for store clusters.
Include a unique pointer so that it was possible to figure out if it's
the same cluster in different program states. This allows comparing
dumps of different states against each other.

Differential Revision: https://reviews.llvm.org/D63362

llvm-svn: 363896
2019-06-19 23:33:51 +00:00
Artem Dergachev f9f6cdb1a8 [analyzer] Fix JSON dumps for location contexts.
Location context ID is a property of the location context, not of an item
within it. It's useful to know the id even when there are no items
in the context, eg. for the purposes of figuring out how did contents
of the Environment for the same location context changed across states.

Differential Revision: https://reviews.llvm.org/D62754

llvm-svn: 363895
2019-06-19 23:33:48 +00:00
Artem Dergachev 3bb7b2ec7f [analyzer] Fix JSON dumps for dynamic type information.
They're now valid JSON.

Differential Revision: https://reviews.llvm.org/D62716

llvm-svn: 363894
2019-06-19 23:33:45 +00:00
Csaba Dabis 32d545f930 [analyzer] print() JSONify chain: Fix possible build-bot breaks
Summary:
Printing constructing_objects could be non-deterministic as it is a map.

llvm-svn: 362101
2019-05-30 15:15:57 +00:00
Csaba Dabis 17604c3486 [analyzer] print() JSONify chain: Fix build-bot breaks
Summary:
Printing out a map structure different in different environments so that
this patch generalize the test-case to check for the 'no stmt'-case
anywhere in the Store.

llvm-svn: 362098
2019-05-30 14:48:43 +00:00
Csaba Dabis ee37e28fd1 [analyzer] print() JSONify chain: Generic stmt_id
Summary: Some environment create less statements so make them generic.
llvm-svn: 362011
2019-05-29 18:58:41 +00:00
Csaba Dabis 13e491cca5 [analyzer] print() JSONify: getNodeLabel implementation
Summary: This patch also rewrites the ProgramPoint printing.

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: cfe-commits, szepet, rnkovacs, a.sidorin, mikhail.ramalho,
             donat.nagy, dkrupp

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62346

llvm-svn: 361997
2019-05-29 18:05:53 +00:00
Csaba Dabis df0a42127c [analyzer] print() JSONify: Program state implementation
Summary: -

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: szepet, rnkovacs, a.sidorin, mikhail.ramalho, donat.nagy,
             dkrupp

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62087

llvm-svn: 361983
2019-05-29 16:22:21 +00:00
Csaba Dabis 35e54eb31e [analyzer] print() JSONify: Constructing objects implementation
Summary: -

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: szepet, rnkovacs, a.sidorin, mikhail.ramalho, donat.nagy,
             dkrupp

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62085

llvm-svn: 361980
2019-05-29 15:58:26 +00:00
Artem Dergachev ca3ace55dc [analyzer] Dump stable identifiers for objects under construction.
This continues the work that was started in r342313, which now gets applied to
object-under-construction tracking in C++. Makes it possible to debug
temporaries by dumping exploded graphs again.

Differential Revision: https://reviews.llvm.org/D54459

llvm-svn: 348200
2018-12-03 22:23:21 +00:00
Artem Dergachev 7e4edbdd1b [analyzer] Fix dumping for SymbolConjured conjured at no particular statement.
llvm-svn: 344944
2018-10-22 20:11:10 +00:00