gcc/
	* doc/invoke.texi: Document the options.
	* flag-types.h (enum sanitize_code): Add
	SANITIZE_POINTER_COMPARE and SANITIZE_POINTER_SUBTRACT.
	* ipa-inline.c (sanitize_attrs_match_for_inline_p): Add handling
	of SANITIZE_POINTER_COMPARE and SANITIZE_POINTER_SUBTRACT.
	* opts.c: Define new sanitizer options.
	* sanitizer.def (BUILT_IN_ASAN_POINTER_COMPARE): Likewise.
	(BUILT_IN_ASAN_POINTER_SUBTRACT): Likewise.
gcc/c/
	* c-typeck.c (pointer_diff): Add new argument and instrument
	pointer subtraction.
	(build_binary_op): Similar for pointer comparison.
gcc/cp/
	* typeck.c (pointer_diff): Add new argument and instrument
	pointer subtraction.
	(cp_build_binary_op): Create compound expression if doing an
	instrumentation.
gcc/testsuite/
	* c-c++-common/asan/pointer-compare-1.c: New test.
	* c-c++-common/asan/pointer-compare-2.c: New test.
	* c-c++-common/asan/pointer-subtract-1.c: New test.
	* c-c++-common/asan/pointer-subtract-2.c: New test.
	* c-c++-common/asan/pointer-subtract-3.c: New test.
	* c-c++-common/asan/pointer-subtract-4.c: New test.
libsanitizer/
	* asan/asan_descriptions.cc: Cherry-pick upstream r319668.
	* asan/asan_descriptions.h: Likewise.
	* asan/asan_report.cc: Likewise.
	* asan/asan_thread.cc: Likewise.
	* asan/asan_thread.h: Likewise.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r255404