Commit Graph

9 Commits

Author SHA1 Message Date
Richard Trieu
639d7b68d6 [ODRHash] static_cast and Stmt hashing.
Add support for static_cast in classes.  Add pointer-independent profiling for
Stmt's, sharing most of the logic with Stmt::Profile.  This is the first of the
deep sub-Decl diffing for error messages.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295890
2017-02-22 22:22:42 +00:00
Simon Pilgrim
732d6eb166 Fix -Wunused-private-field warning by removing unused ODRHash reference field from ODRDeclVisitor
llvm-svn: 295828
2017-02-22 13:19:24 +00:00
Richard Trieu
e7f7ed2be7 Add more ODR checking.
Add the basics for the ODRHash class, which will only process Decl's from
a whitelist, which currently only has AccessSpecDecl.  Different access
specifiers in merged classes can now be detected.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295800
2017-02-22 01:11:25 +00:00
Richard Trieu
dc4cb02470 Revert r295421, new ODR checker for modules, to fix build bot.
llvm-svn: 295427
2017-02-17 07:19:24 +00:00
Richard Trieu
cb6b72628e Add better ODR checking for modules.
A slightly weaker form of ODR checking than previous attempts, but hopefully
won't break the modules build bot.  Future work will be needed to catch all
cases.

When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295421
2017-02-17 05:54:30 +00:00
Richard Trieu
e55fb7f6f1 Revert r295284: Add better ODR checking for modules.
Fix modules build bot.

llvm-svn: 295293
2017-02-16 07:09:18 +00:00
Richard Trieu
f351ac8987 Add better ODR checking for modules.
Recommit r293585 that was reverted in r293611 with new fixes.  The previous
issue was determined to be an overly aggressive AST visitor from forward
declared objects.  The visitor will now only deeply visit certain Decl's and
only do a shallow information extraction from all other Decl's.

When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295284
2017-02-16 04:53:40 +00:00
Sam McCall
61e29aafa7 Revert r293585 "Add better ODR checking for modules."
We're seeing what we believe are false positives. (It's hard to tell with the
available diagnostics, and I'm not sure how to reduce them yet).
I'll send Richard reproduction details offline.

djasper/chandlerc suggested this should be a warning for now, to make rolling it
out feasible.

llvm-svn: 293611
2017-01-31 08:24:40 +00:00
Richard Trieu
fa3d93a148 Add better ODR checking for modules.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taked from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 293585
2017-01-31 01:44:15 +00:00