The new format requires to specify both the type of the access
and its size. This patch fixes setting access sizes for TBAA tags
that denote accesses to structure members. This fix affects all
future TBAA metadata tests for the new format, so I guess we
don't need any special tests for this fix.
Differential Revision: https://reviews.llvm.org/D41452
llvm-svn: 321250
Diagnose 'unreachable' UB when a noreturn function returns.
1. Insert a check at the end of functions marked noreturn.
2. A decl may be marked noreturn in the caller TU, but not marked in
the TU where it's defined. To diagnose this scenario, strip away the
noreturn attribute on the callee and insert check after calls to it.
Testing: check-clang, check-ubsan, check-ubsan-minimal, D40700
rdar://33660464
Differential Revision: https://reviews.llvm.org/D40698
llvm-svn: 321231
At least <http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-android/
builds/6013/steps/annotate/logs/stdio> complains about
__ubsan::__ubsan_handle_function_type_mismatch_abort (compiler-rt
lib/ubsan/ubsan_handlers.cc) returning now despite being declared 'noreturn', so
looks like a different approach is needed for the function_type_mismatch check
to be called also in cases that may ultimately succeed.
llvm-svn: 320982
As discussed in the mail thread <https://groups.google.com/a/isocpp.org/forum/
#!topic/std-discussion/T64_dW3WKUk> "Calling noexcept function throug non-
noexcept pointer is undefined behavior?", such a call should not be UB.
However, Clang currently warns about it.
There is no cheap check whether two function type_infos only differ in noexcept,
so pass those two type_infos as additional data to the function_type_mismatch
handler (with the optimization of passing a null "static callee type" info when
that is already noexcept, so the additional check can be avoided anyway). For
the Itanium ABI (which appears to be the only one that happens to be used on
platforms that support -fsanitize=function, and which appears to only record
noexcept information for pointer-to-function type_infos, not for function
type_infos themselves), we then need to check the mangled names for occurrence
of "Do" representing "noexcept".
This is the cfe part of a patch covering both cfe and compiler-rt.
Differential Revision: https://reviews.llvm.org/D40720
llvm-svn: 320978
Most of the -Wsign-compare warnings are due to the fact that
enums are signed by default in the MS ABI, while the
tautological comparison warnings trigger on x86 builds where
sizeof(size_t) is 4 bytes, so N > numeric_limits<unsigned>::max()
is always false.
Differential Revision: https://reviews.llvm.org/D41256
llvm-svn: 320750
This is a follow-up to r320128. Eli pointed out that there is some gray
area in the language standard about whether the constant size is exact,
or a lower bound.
https://reviews.llvm.org/D40940
llvm-svn: 320185
The basic idea behind this patch is that since in strict aliasing
mode all accesses to union members require their outermost
enclosing union objects to be specified explicitly, then for a
couple given accesses to union members of the form
p->a.b.c...
q->x.y.z...
it is known they can only alias if both p and q point to the same
union type and offset ranges of members a.b.c... and x.y.z...
overlap. Note that the actual types of the members do not matter.
Specifically, in this patch we do the following:
* Make unions to be valid TBAA base access types. This enables
generation of TBAA type descriptors for unions.
* Encode union types as structures with a single member of a
special "union member" type. Currently we do not encode
information about sizes of types, but conceptually such union
members are considered to be of the size of the whole union.
* Encode accesses to direct and indirect union members, including
member arrays, as accesses to these special members. All
accesses to members of a union thus get the same offset, which
is the offset of the union they are part of. This means the
existing LLVM TBAA machinery is able to handle such accesses
with no changes.
While this is already an improvement comparing to the current
situation, that is, representing all union accesses as may-alias
ones, there are further changes planned to complete the support
for unions. One of them is storing information about access sizes
so we can distinct accesses to non-overlapping union members,
including accesses to different elements of member arrays.
Another change is encoding type sizes in order to make it
possible to compute offsets within constant-indexed array
elements. These enhancements will be addressed with separate
patches.
Differential Revision: https://reviews.llvm.org/D39455
llvm-svn: 319413
Summary:
This change allows generalizing pointers in type signatures used for
cfi-icall by enabling the -fsanitize-cfi-icall-generalize-pointers flag.
This works by 1) emitting an additional generalized type signature
metadata node for functions and 2) llvm.type.test()ing for the
generalized type for translation units with the flag specified.
This flag is incompatible with -fsanitize-cfi-cross-dso because it would
require emitting twice as many type hashes which would increase artifact
size.
Reviewers: pcc, eugenis
Reviewed By: pcc
Subscribers: kcc
Differential Revision: https://reviews.llvm.org/D39358
llvm-svn: 317044
This patch fixes various places in clang to propagate may-alias
TBAA access descriptors during construction of lvalues, thus
eliminating the need for the LValueBaseInfo::MayAlias flag.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D39008
llvm-svn: 316988
For non-zero alloca addr space, alloca is usually casted to default addr
space immediately.
For non-vla, alloca is inserted at AllocaInsertPt, therefore the addr
space cast should also be insterted at AllocaInsertPt. However,
for vla, alloca is inserted at the current insertion point of IRBuilder,
therefore the addr space cast should also inserted at the current
insertion point of IRBuilder.
Currently clang always insert addr space cast at AllocaInsertPt, which
causes invalid IR.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D39374
llvm-svn: 316909
Builder save/restores insertion pointer when emitting addr space cast
for alloca, but does not save/restore debug loc, which causes verifier
failure for certain call instructions.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D39069
llvm-svn: 316484
The main change is that now we generate TBAA info before
constructing the resulting lvalue instead of constructing lvalue
with some default TBAA info and fixing it as necessary
afterwards. We also keep the TBAA info close to lvalue base info,
which is supposed to simplify their future merging.
This patch should not bring in any functional changes.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38947
llvm-svn: 315989
This patch addresses the rest of the cases where we pass lvalue
base info, but do not provide corresponding TBAA info.
This patch should not bring in any functional changes.
This is part of D38126 reworked to be a separate patch to make
reviewing easier.
Differential Revision: https://reviews.llvm.org/D38945
llvm-svn: 315986
Ivan A. Kosarev
Vedant Kumar
Stephan Bergmann
Zachary Turner
Hal Finkel
Vlad Tsyrklevich
Yaxun Liu