The end result is now we eagarly constant-fold symbols in the analyzer that are perfectly constrained
to be a constant value. This allows us to recover some path-sensitivity in some cases by lowering
the required level of reasoning power needed to evaluate some expressions.
The net win from this change is that the false positive in PR 8015 is fixed, and we also
find more idempotent operations bugs.
We do, however, regress with the BugReporterVisitors, which need to be modified to understand
this constant folding (and look past it). This causes some diagnostic regressions in plist-output.m
which will get addressed in a future patch. plist-output.m is now marked XFAIL, while
plist-output-alternate.m now tests that the plist output is working, but with the suboptimal
diagnostics. This second test file will eventually be removed.
llvm-svn: 113477
- Added wasReferenced function to PseudoConstantAnalysis to determine if a variable was ever referenced in a function (outside of a self-assignment)
- BlockDeclRefExpr referenced variables are now explicitly added to the non-constant list
- Remove unnecessary ignore of implicit casts
- Generalized parameter self-assign detection to detect deliberate self-assigns of variables to avoid unused variable warnings
- Updated test cases with deliberate self-assignments
- Fixed bug with C++ references and pseudoconstants
- Added test case for C++ references and pseudoconstants
llvm-svn: 111965
- Unfinished analysis may still report valid warnings if the path was completely analyzed
- New 'CanVary' heuristic to recursively determine if a subexpression has a varying element
- Updated test cases, including one known bug
- Exposed GRCoreEngine through GRExprEngine
llvm-svn: 110970
- Added checks for static local variables, self assigned parameters, and truncating/extending self assignments
- Removed command line option (now default with --analyze)
- Updated test cases to pass with idempotent operation warnings
llvm-svn: 108550
As a bonus, fix the warning for || and && operators; it was emitted even if one of the operands had side effects, e.g:
x || test_logical_foo1();
emitted a bogus "expression result unused" for 'x'.
llvm-svn: 107274
a scalar variable with a scalar parameter. This is a
form of defensive programming. If the variable is unused,
it will be caused by -Wunused-variable.
llvm-svn: 98795
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
and replace the 'clang-cc' option '-analyzer-store=basic-new-cast' with
'-analyzer-store=basic-old-cast'. We'll keep the old CastRegion implementation
around for a little while for regression testing.
llvm-svn: 75209
GRTransferFuncs had the conflated role of both constructing SVals (symbolic
expressions) as well as handling checker-specific logic. Now SValuator has the
role of constructing SVals from expressions and GRTransferFuncs just handles
checker-specific logic. The motivation is by separating these two concepts we
will be able to much more easily create richer constraint-generating logic
without coupling it to the main checker transfer function logic.
We now have one implementation of SValuator: SimpleSValuator.
SimpleSValuator is essentially the SVal-related logic that was in GRSimpleVals
(which is removed in this patch). This includes the logic for EvalBinOp,
EvalCast, etc. Because SValuator has a narrower role than the old
GRTransferFuncs, the interfaces are much simpler, and so is the implementation
of SimpleSValuator compared to GRSimpleVals. I also did a line-by-line review of
SVal-related logic in GRSimpleVals and cleaned it up while moving it over to
SimpleSValuator.
As a consequence of removing GRSimpleVals, there is no longer a
'-checker-simple' option. The '-checker-cfref' did everything that option did
but also ran the retain/release checker. Of course a user may not always wish to
run the retain/release checker, nor do we wish core analysis logic buried in the
checker-specific logic. The next step is to refactor the logic in CFRefCount.cpp
to separate out these pieces into the core analysis engine.
llvm-svn: 74229
printf-like functions, both builtin functions and those in the
C library. The function-call checker now queries this attribute do
determine if we have a printf-like function, rather than scanning
through the list of "known functions IDs". However, there are 5
functions they are not yet "builtins", so the function-call checker
handles them specifically still:
- fprintf and vfprintf: the builtins mechanism cannot (yet)
express FILE* arguments, so these can't be encoded.
- NSLog: the builtins mechanism cannot (yet) express NSString*
arguments, so this (and NSLogv) can't be encoded.
- asprintf and vasprintf: these aren't part of the C99 standard
library, so we really shouldn't be defining them as builtins in
the general case (and we don't seem to have the machinery to make
them builtins only on certain targets and depending on whether
extensions are enabled).
llvm-svn: 64512
Argyrios Kyrtzidis