Summary:
So far we used a value of 10 which was useful for testing but produces many false-positives in real programs. The usual suspicious clones we find seem to be at around a complexity value of 70 and for normal clone-reporting everything above 50 seems to be a valid normal clone for users, so let's just go with 50 for now and set this as the new default value.
This patch also explicitly sets the complexity value for the regression tests as they serve more of a regression testing/debugging purpose and shouldn't really be reported by default in real programs. I'll add more tests that reflect actual found bugs that then need to pass with the default setting in the future.
Reviewers: NoQ
Subscribers: cfe-commits, javed.absar, xazax.hun, v.g.vassilev
Differential Revision: https://reviews.llvm.org/D34178
llvm-svn: 312468
Highlight code clones referenced by the warning message with the help of
the extra notes feature recently introduced in r283092.
Change warning text to more clang-ish. Remove suggestions from the copy-paste
error checker diagnostics, because currently our suggestions are strictly 50%
wrong (we do not know which of the two code clones contains the error), and
for that reason we should not sound as if we're actually suggesting this.
Hopefully a better solution would bring them back.
Make sure the suspicious clone pair structure always mentions
the correct variable for the second clone.
Differential Revision: https://reviews.llvm.org/D24916
llvm-svn: 283094
If a call expression represents a method call of a class template,
and the method itself isn't templated, then the method may be considered
to be a template instantiation without template specialization arguments.
No longer crash when we could not find template specialization arguments.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23780
llvm-svn: 279529
So far macro-generated code was treated by the CloneDetector as normal code.
This caused that some macros where reported as false-positive clones because
large chunks of code coming from otherwise concise macro expansions were treated
as copy-pasted code.
This patch ensures that macros are treated in the same way as literals/function
calls. This prevents macros that expand into multiple statements
from being reported as clones.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23316
llvm-svn: 279367
For example, code samples `isa<Stmt>(S)' and `isa<Expr>(S)'
are no longer considered to be clones.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23555
llvm-svn: 279366
The original clone checker tries to find copy-pasted code that is exactly
identical to the original code, up to minor details.
As an example, if the copy-pasted code has all references to variable 'a'
replaced with references to variable 'b', it is still considered to be
an exact clone.
The new check finds copy-pasted code in which exactly one variable seems
out of place compared to the original code, which likely indicates
a copy-paste error (a variable was forgotten to be renamed in one place).
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23314
llvm-svn: 279056
CallExpr may have a null direct callee when the callee function is not
known in compile-time. Do not try to take callee name in this case.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23320
llvm-svn: 278238
CloneDetector should be able to detect clones with renamed variables.
However, if variables are referenced multiple times around the code sample,
the usage patterns need to be recognized.
For example, (x < y ? y : x) and (y < x ? y : x) are no longer clones,
however (a < b ? b : a) is still a clone of the former.
Variable patterns are computed and compared during a separate filtering pass.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D22982
llvm-svn: 277757
If a target triple is not specified, the default host triple is used,
which is not good for compiling inline assembler code.
Patch by Raphael Isemann!
llvm-svn: 277473
So far the CloneDetector only respected the kind of each statement when
searching for clones. This patch refines the way the CloneDetector collects data
from each statement by providing methods for each statement kind,
that will read the kind-specific attributes.
For example, statements 'a < b' and 'a > b' are no longer considered to be
clones, because they are different in operation code, which is an attribute
specific to the BinaryOperator statement kind.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D22514
llvm-svn: 277449
This patch adds the CloneDetector class which allows searching source code
for clones.
For every statement or group of statements within a compound statement,
CloneDetector computes a hash value, and finds clones by detecting
identical hash values.
This initial patch only provides a simple hashing mechanism
that hashes the kind of each sub-statement.
This patch also adds CloneChecker - a simple static analyzer checker
that uses CloneDetector to report copy-pasted code.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D20795
llvm-svn: 276782
Raphael Isemann