linux/lib/mpi
Nathan Chancellor 18f1ca4685 lib/mpi: Fix 64-bit MIPS build with Clang
When building 64r6_defconfig with CONFIG_MIPS32_O32 disabled and
CONFIG_CRYPTO_RSA enabled:

lib/mpi/generic_mpih-mul1.c:37:24: error: invalid use of a cast in a
inline asm context requiring an l-value: remove the cast
or build with -fheinous-gnu-extensions
                umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb);
                ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/mpi/longlong.h:664:22: note: expanded from macro 'umul_ppmm'
                 : "=d" ((UDItype)(w0))
                         ~~~~~~~~~~^~~
lib/mpi/generic_mpih-mul1.c:37:13: error: invalid use of a cast in a
inline asm context requiring an l-value: remove the cast
or build with -fheinous-gnu-extensions
                umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb);
                ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/mpi/longlong.h:668:22: note: expanded from macro 'umul_ppmm'
                 : "=d" ((UDItype)(w1))
                         ~~~~~~~~~~^~~
2 errors generated.

This special case for umul_ppmm for MIPS64r6 was added in
commit bbc25bee37 ("lib/mpi: Fix umul_ppmm() for MIPS64r6"), due to
GCC being inefficient and emitting a __multi3 intrinsic.

There is no such issue with clang; with this patch applied, I can build
this configuration without any problems and there are no link errors
like mentioned in the commit above (which I can still reproduce with
GCC 9.3.0 when that commit is reverted). Only use this definition when
GCC is being used.

This really should have been caught by commit b0c091ae04 ("lib/mpi:
Eliminate unused umul_ppmm definitions for MIPS") when I was messing
around in this area but I was not testing 64-bit MIPS at the time.

Link: https://github.com/ClangBuiltLinux/linux/issues/885
Reported-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-04-30 15:19:33 +10:00
..
generic_mpih-add1.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-lshift.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-mul1.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-mul2.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-mul3.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-rshift.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
generic_mpih-sub1.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
longlong.h lib/mpi: Fix 64-bit MIPS build with Clang 2020-04-30 15:19:33 +10:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mpi-bit.c MPILIB: Provide count_leading/trailing_zeros() based on arch functions 2012-10-08 13:50:11 +10:30
mpi-cmp.c MPILIB: Fix comparison of negative MPIs 2015-01-14 16:10:12 +00:00
mpi-inline.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
mpi-internal.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
mpi-pow.c Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-05 13:31:19 +09:00
mpicoder.c lib/mpi: kunmap after finishing accessing buffer 2017-08-22 14:45:01 +08:00
mpih-cmp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
mpih-div.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
mpih-mul.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26 2019-05-24 17:27:10 +02:00
mpiutil.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00