diff options
| author | Peter Collingbourne <pcc-at-google.com@ffmpeg.org> | 2019-08-21 11:55:25 -0700 |
|---|---|---|
| committer | Carl Eugen Hoyos <ceffmpeg@gmail.com> | 2019-08-22 11:22:07 +0200 |
| commit | 9bcb1cb6ed50e66e0489beb871eed83533b3de97 (patch) | |
| tree | 503f7d90ff784af838a56a93ecd6ce0a17a89be3 /libavutil/aarch64 | |
| parent | c87237d10511a28a3cfb7bb88ed2af1907dc8f66 (diff) | |
| download | ffmpeg-9bcb1cb6ed50e66e0489beb871eed83533b3de97.tar.gz | |
Add assembly support for -fsanitize=hwaddress tagged globals.
As of LLVM r368102, Clang will set a pointer tag in bits 56-63 of the
address of a global when compiling with -fsanitize=hwaddress. This requires
an adjustment to assembly code that takes the address of such globals: the
code cannot use the regular R_AARCH64_ADR_PREL_PG_HI21 relocation to refer
to the global, since the tag would take the address out of range. Instead,
the code must use the non-checking (_NC) variant of the relocation (the
link-time check is substituted by a runtime check).
This change makes the necessary adjustment in the movrel macro, where it is
needed when compiling with -fsanitize=hwaddress.
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Martin Storsjö
Reviewed-by: Janne Grunau
Diffstat (limited to 'libavutil/aarch64')
| -rw-r--r-- | libavutil/aarch64/asm.S | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/libavutil/aarch64/asm.S b/libavutil/aarch64/asm.S index 5c329430fd..3ac2ba0d52 100644 --- a/libavutil/aarch64/asm.S +++ b/libavutil/aarch64/asm.S @@ -32,6 +32,10 @@ # define FUNC # #endif +#ifndef __has_feature +# define __has_feature(x) 0 +#endif + .macro function name, export=0, align=2 .macro endfunc ELF .size \name, . - \name @@ -94,7 +98,11 @@ ELF .size \name, . - \name add \rd, \rd, :lo12:\val+(\offset) .endif #elif CONFIG_PIC +# if __has_feature(hwaddress_sanitizer) + adrp \rd, :pg_hi21_nc:\val+(\offset) +# else adrp \rd, \val+(\offset) +# endif add \rd, \rd, :lo12:\val+(\offset) #else ldr \rd, =\val+\offset |