Hi Joshua: > Does Asan work for RISC-V currently? It seems that '-fsanitize=address' is > still unsupported for RISC-V. If I add '--enable-libsanitizer' in Makefile.in > to reconfigure, there are compiling errors. Is it because # libsanitizer not supported rv32, but it will break the rv64 multi-lib build, so we disable that temporally until rv32 supported# in Makefile.in?
IIUC, you mean the Makefile in riscv-gnu-toolchain instead of upstream GCC, right? I guess we can make a configure option to enable that and check it does not come with multi-lib, or maybe you could fix that on GCC's configure script to make the multi-lib build be ignored for rv32? On Wed, Apr 20, 2022 at 2:13 PM joshua via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > Does Asan work for RISC-V currently? It seems that '-fsanitize=address' is > still unsupported for RISC-V. If I add '--enable-libsanitizer' in Makefile.in > to reconfigure, there are compiling errors. > Is it because # libsanitizer not supported rv32, but it will break the rv64 > multi-lib build, so we disable that temporally until rv32 supported# in > Makefile.in? > > > ------------------------------------------------------------------ > 发件人:Jim Wilson <j...@sifive.com> > 发送时间:2020年10月29日(星期四) 07:59 > 收件人:gcc-patches <gcc-patches@gcc.gnu.org> > 抄 送:cooper.joshua <cooper.jos...@linux.alibaba.com>; Jim Wilson > <j...@sifive.com> > 主 题:[PATCH] Asan changes for RISC-V. > > We have only riscv64 asan support, there is no riscv32 support as yet. So I > need to be able to conditionally enable asan support for the riscv target. I > implemented this by returning zero from the asan_shadow_offset function. This > requires a change to toplev.c and docs in target.def. > > The asan support works on a 5.5 kernel, but does not work on a 4.15 kernel. > The problem is that the asan high memory region is a small wedge below > 0x4000000000. The new kernel puts shared libraries at 0x3fffffffff and going > down which works. But the old kernel puts shared libraries at 0x2000000000 > and going up which does not work, as it isn't in any recognized memory > region. This might be fixable with more asan work, but we don't really need > support for old kernel versions. > > The asan port is curious in that it uses 1<<29 for the shadow offset, but all > other 64-bit targets use a number larger than 1<<32. But what we have is > working OK for now. > > I did a make check RUNTESTFLAGS="asan.exp" on Fedora rawhide image running on > qemu and the results look reasonable. > > === gcc Summary === > > # of expected passes 1905 > # of unexpected failures 11 > # of unsupported tests 224 > > === g++ Summary === > > # of expected passes 2002 > # of unexpected failures 6 > # of unresolved testcases 1 > # of unsupported tests 175 > > OK? > > Jim > > 2020-10-28 Jim Wilson <j...@sifive.com> > > gcc/ > * config/riscv/riscv.c (riscv_asan_shadow_offset): New. > (TARGET_ASAN_SHADOW_OFFSET): New. > * doc/tm.texi: Regenerated. > * target.def (asan_shadow_offset); Mention that it can return zero. > * toplev.c (process_options): Check for and handle zero return from > targetm.asan_shadow_offset call. > > Co-Authored-By: cooper.joshua <cooper.jos...@linux.alibaba.com> > --- > gcc/config/riscv/riscv.c | 16 ++++++++++++++++ > gcc/doc/tm.texi | 3 ++- > gcc/target.def | 3 ++- > gcc/toplev.c | 3 ++- > 4 files changed, 22 insertions(+), 3 deletions(-) > > diff --git a/gcc/config/riscv/riscv.c b/gcc/config/riscv/riscv.c > index 989a9f15250..6909e200de1 100644 > --- a/gcc/config/riscv/riscv.c > +++ b/gcc/config/riscv/riscv.c > @@ -5299,6 +5299,19 @@ riscv_gpr_save_operation_p (rtx op) > return true; > } > > +/* Implement TARGET_ASAN_SHADOW_OFFSET. */ > + > +static unsigned HOST_WIDE_INT > +riscv_asan_shadow_offset (void) > +{ > + /* We only have libsanitizer support for RV64 at present. > + > + This number must match kRiscv*_ShadowOffset* in the file > + libsanitizer/asan/asan_mapping.h which is currently 1<<29 for rv64, > + even though 1<<36 makes more sense. */ > + return TARGET_64BIT ? (HOST_WIDE_INT_1 << 29) : 0; > +} > + > /* Initialize the GCC target structure. */ > #undef TARGET_ASM_ALIGNED_HI_OP > #define TARGET_ASM_ALIGNED_HI_OP "\t.half\t" > @@ -5482,6 +5495,9 @@ riscv_gpr_save_operation_p (rtx op) > #undef TARGET_NEW_ADDRESS_PROFITABLE_P > #define TARGET_NEW_ADDRESS_PROFITABLE_P riscv_new_address_profitable_p > > +#undef TARGET_ASAN_SHADOW_OFFSET > +#define TARGET_ASAN_SHADOW_OFFSET riscv_asan_shadow_offset > + > struct gcc_target targetm = TARGET_INITIALIZER; > > #include "gt-riscv.h" > diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi > index 24c37f655c8..39c596b647a 100644 > --- a/gcc/doc/tm.texi > +++ b/gcc/doc/tm.texi > @@ -12078,7 +12078,8 @@ is zero, which disables this optimization. > @deftypefn {Target Hook} {unsigned HOST_WIDE_INT} TARGET_ASAN_SHADOW_OFFSET > (void) > Return the offset bitwise ored into shifted address to get corresponding > Address Sanitizer shadow memory address. NULL if Address Sanitizer is not > -supported by the target. > +supported by the target. May return 0 if Address Sanitizer is not supported > +by a subtarget. > @end deftypefn > > @deftypefn {Target Hook} {unsigned HOST_WIDE_INT} TARGET_MEMMODEL_CHECK > (unsigned HOST_WIDE_INT @var{val}) > diff --git a/gcc/target.def b/gcc/target.def > index ed2da154e30..268b56b6ebd 100644 > --- a/gcc/target.def > +++ b/gcc/target.def > @@ -4452,7 +4452,8 @@ DEFHOOK > (asan_shadow_offset, > "Return the offset bitwise ored into shifted address to get corresponding\n\ > Address Sanitizer shadow memory address. NULL if Address Sanitizer is not\n\ > -supported by the target.", > +supported by the target. May return 0 if Address Sanitizer is not > supported\n\ > +by a subtarget.", > unsigned HOST_WIDE_INT, (void), > NULL) > > diff --git a/gcc/toplev.c b/gcc/toplev.c > index 20e231f4d2a..cf89598252c 100644 > --- a/gcc/toplev.c > +++ b/gcc/toplev.c > @@ -1834,7 +1834,8 @@ process_options (void) > } > > if ((flag_sanitize & SANITIZE_USER_ADDRESS) > - && targetm.asan_shadow_offset == NULL) > + && ((targetm.asan_shadow_offset == NULL) > + || (targetm.asan_shadow_offset () == 0))) > { > warning_at (UNKNOWN_LOCATION, 0, > "%<-fsanitize=address%> not supported for this target"); > -- > 2.17.1 >