Optimize the encoding of "covered" metadata by:
1. Reducing feature mask from 4 bytes to 1 byte (needs increase once we
reach more than 8 features).
2. Only emitting UAR stack args size if it is non-zero, saving 4 bytes
in the common case.
One caveat is that the emitted metadata for function PC (offset), size,
and UAR size (if enabled) are no longer aligned to 4 bytes.
SanitizerBinaryMetadata version base is increased to 2, since the change
is backwards incompatible.
Reviewed By: dvyukov
Differential Revision: https://reviews.llvm.org/D143482
There are no intrinsic functions that leak arguments.
If the called function does not return, the current function
does not return as well, so no possibility of use-after-return.
Sanitizer function also don't leak or don't return.
It's safe to both pass pointers to local variables to them
and to tail-call them.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D142190
There are no intrinsic functions that leak arguments.
If the called function does not return, the current function
does not return as well, so no possibility of use-after-return.
Sanitizer function also don't leak or don't return.
It's safe to both pass pointers to local variables to them
and to tail-call them.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D142190
Only mark functions that have address-taken locals
as requiring UAR checking.
On a large internal app this reduces number of marked functions
from 78441 to 66618. Mostly small, trivial getter/setter-type
functions are unmarked, but also some amount of larger
number-crunching-type functions are unmarked as well.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D139811
Currently per-function metadata consists of:
(start-pc, size, features)
This adds a new UAR feature and if it's set an additional element:
(start-pc, size, features, stack-args-size)
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D136078
