flag-types.h (enum sanitize_code): Add SANITIZE_SHIFT_BASE and SANITIZE_SHIFT_EXPONENT...

	* flag-types.h (enum sanitize_code): Add SANITIZE_SHIFT_BASE
	and SANITIZE_SHIFT_EXPONENT, change SANITIZE_SHIFT to bitwise
	or of them, renumber other enumerators.
	* opts.c (sanitizer_opts): Add shift-base and shift-exponent.
	* doc/invoke.texi: Document -fsanitize=shift-base and
	-fsanitize-shift-exponent, document -fsanitize=shift as
	having those 2 suboptions.
c-family/
	* c-ubsan.c (ubsan_instrument_shift): Handle split
	-fsanitize=shift-base and -fsanitize=shift-exponent.
testsuite/
	* gcc.dg/ubsan/c99-shift-3.c: New test.
	* gcc.dg/ubsan/c99-shift-4.c: New test.
	* gcc.dg/ubsan/c99-shift-5.c: New test.
	* gcc.dg/ubsan/c99-shift-6.c: New test.

From-SVN: r242005

1 files changed, 15 insertions, 0 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 17c5c22..76b8540 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -10560,6 +10560,21 @@ at runtime.  Current suboptions are:
 This option enables checking that the result of a shift operation is
 not undefined.  Note that what exactly is considered undefined differs
 slightly between C and C++, as well as between ISO C90 and C99, etc.
+This option has two suboptions, @option{-fsanitize=shift-base} and
+@option{-fsanitize=shift-exponent}.
+
+@item -fsanitize=shift-exponent
+@opindex fsanitize=shift-exponent
+This option enables checking that the second argument of a shift operation
+is not negative and is smaller than the precision of the promoted first
+argument.
+
+@item -fsanitize=shift-base
+@opindex fsanitize=shift-base
+If the second argument of a shift operation is within range, check that the
+result of a shift operation is not undefined.  Note that what exactly is
+considered undefined differs slightly between C and C++, as well as between
+ISO C90 and C99, etc.
 
 @item -fsanitize=integer-divide-by-zero
 @opindex fsanitize=integer-divide-by-zero