Shadow checks are disabled and memory loads always produce fully initialized
values in functions that don't have a sanitize_memory attribute. Value and
argument shadow is propagated as usual.
This change also updates blacklist behaviour to match the above.
llvm-svn: 176247
These are two related changes (one in llvm, one in clang).
LLVM:
- rename address_safety => sanitize_address (the enum value is the same, so we preserve binary compatibility with old bitcode)
- rename thread_safety => sanitize_thread
- rename no_uninitialized_checks -> sanitize_memory
CLANG:
- add __attribute__((no_sanitize_address)) as a synonym for __attribute__((no_address_safety_analysis))
- add __attribute__((no_sanitize_thread))
- add __attribute__((no_sanitize_memory))
for S in address thread memory
If -fsanitize=S is present and __attribute__((no_sanitize_S)) is not
set llvm attribute sanitize_S
llvm-svn: 176075
This patch makes asan instrument memory accesses with unusual sizes (e.g. 5 bytes or 10 bytes), e.g. long double or
packed structures.
Instrumentation is done with two 1-byte checks
(first and last bytes) and if the error is found
__asan_report_load_n(addr, real_size) or
__asan_report_store_n(addr, real_size)
is called.
Also, call these two new functions in memset/memcpy
instrumentation.
asan-rt part will follow.
llvm-svn: 175507
It is way too slow. Change the default option value to 0.
Always do exact shadow propagation for unsigned ICmp with constants, it is
cheap (under 1% cpu time) and required for correctness.
llvm-svn: 173682
Only for integers, pointers, and vectors of those. No floats.
Instrumentation seems very heavy, and may need to be replaced
with some approximation in the future.
llvm-svn: 173452
This fixes va_start/va_copy of a va_list field which happens to not
be laid out at a 16-byte boundary.
Differential Revision: http://llvm-reviews.chandlerc.com/D276
llvm-svn: 172128
This changes adds shadow and origin propagation for unknown intrinsics
by examining the arguments and ModRef behaviour. For now, only 3 classes
of intrinsics are handled:
- those that look like simple SIMD store
- those that look like simple SIMD load
- those that don't have memory effects and look like arithmetic/logic/whatever
operation on simple types.
llvm-svn: 170530
When ASan replaces <alloca instruction> with
<offset into a common large alloca>, it should also patch
llvm.dbg.declare calls and replace debug info descriptors to mark
that we've replaced alloca with a value that stores an address
of the user variable, not the user variable itself.
See PR11818 for more context.
llvm-svn: 169984
Instead of unconditionally storing origin with every application store,
only do this when the shadow of the stored value is != 0.
This change also delays instrumentation of stores until after the walk over
function's instructions, because adding new basic blocks confuses InstVisitor.
We only keep 1 origin value per 4 bytes of application memory. This change
fixes the bug when a store of a single clean byte wiped the origin for the
whole 4-byte area.
Since stores of uninitialized values are relatively uncommon, this change
improves performance of track-origins mode by 5% median and by up to 47% on
specs.
llvm-svn: 169490
