Summary:
Keeping msan a function pass requires replacing the module level initialization:
That means, don't define a ctor function which calls __msan_init, instead just
declare the init function at the first access, and add that to the global ctors
list.
Changes:
- Pull the actual sanitizer and the wrapper pass apart.
- Add a newpm msan pass. The function pass inserts calls to runtime
library functions, for which it inserts declarations as necessary.
- Update tests.
Caveats:
- There is one test that I dropped, because it specifically tested the
definition of the ctor.
Reviewers: chandlerc, fedor.sergeev, leonardchan, vitalybuka
Subscribers: sdardis, nemanjai, javed.absar, hiraditya, kbarton, bollu, atanasyan, jsji
Differential Revision: https://reviews.llvm.org/D55647
llvm-svn: 350305
Introduce the -msan-kernel flag, which enables the kernel instrumentation.
The main differences between KMSAN and MSan instrumentations are:
- KMSAN implies msan-track-origins=2, msan-keep-going=true;
- there're no explicit accesses to shadow and origin memory.
Shadow and origin values for a particular X-byte memory location are
read and written via pointers returned by
__msan_metadata_ptr_for_load_X(u8 *addr) and
__msan_store_shadow_origin_X(u8 *addr, uptr shadow, uptr origin);
- TLS variables are stored in a single struct in per-task storage. A call
to a function returning that struct is inserted into every instrumented
function before the entry block;
- __msan_warning() takes a 32-bit origin parameter;
- local variables are poisoned with __msan_poison_alloca() upon function
entry and unpoisoned with __msan_unpoison_alloca() before leaving the
function;
- the pass doesn't declare any global variables or add global constructors
to the translation unit.
llvm-svn: 341637
Philip Pfaffe