Within the M-profile of the Arm architecture, some instructions
admit both a 16-bit and a 32-bit encoding. For those instructions,
some assemblers support the use of the .n (narrow) and .w (wide)
suffixes to force a choice of instruction encoding width.
Forcing the size of encodings may be useful to ensure alignment
of code, which can have a significant performance impact on some
microarchitectures.
It is for this reason that a previous commit introduced explicit
.w suffixes into what was believed to be M-profile only assembly
in library/bn_mul.h.
This change, however, introduced two issues:
- First, the assembly block in question is used also for Armv7-A
systems, on which the .n/.w distinction is not meaningful
(all instructions are 32-bit).
- Second, compiler support for .n/.w suffixes appears patchy,
leading to compilation failures even when building for M-profile
targets.
This commit removes the .w annotations in order to restore working
code, deferring controlled re-introduction for the sake of performance.
Fixes#6089.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
The variable is a local variable for the i386 bignum assembly only;
introduce it as part of the start/finish macros.
It can be noted that the variable is initialize to 0 within MULADDC_INIT,
so there are no data dependencies across blocks of MULADDC_INIT/CORE/STOP.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Add memory constraints to the aarch64 inline assembly in MULADDC_STOP.
This fixes an issue where Clang 12 and 13 were generating
non-functional code on aarch64 platforms. See #4962, #4943
for further details.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
MULADDC_CORE reads from (%%rsi) and writes to (%%rdi). This fragment is
repeated up to 16 times, and %%rsi and %%rdi are s and d on entry
respectively. Hence the complete asm statement reads 16 64-bit words
from memory starting at s, and writes 16 64-bit words starting at d.
Without any declaration of modified memory, Clang 12 and Clang 13 generated
non-working code for mbedtls_mpi_mod_exp. The constraints make the unit
tests pass with Clang 12.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Also remove preprocessor logic for MBEDTLS_CONFIG_FILE, since
build_info.h alreadyy handles it.
This commit was generated using the following script:
# ========================
#!/bin/sh
git ls-files | grep -v '^include/mbedtls/build_info\.h$' | xargs sed -b -E -i '
/^#if !?defined\(MBEDTLS_CONFIG_FILE\)/i#include "mbedtls/build_info.h"
//,/^#endif/d
'
# ========================
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
These macros were moved into a header and now check-names.sh is failing.
Add an MBEDTL_ prefix to the macro names to make it pass.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Move `include/mbedtls/bn_mul.h` to `library/bn_mul.h`.
Update includes and references to `bn_mul.h` to new location.
Also remove internal headers from `cpp_dummy_build.cpp` as it should only
test public headers in the library.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
