mirror/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-03-01 13:13:28 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Move non-function-specific macro outside of function definition

Browse Source 
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
This commit is contained in:
Dave Rodgman 2023-08-21 07:54:11 +01:00
parent 42391b4378
commit 3ab114e3da
1 changed files with 22 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
library/constant_time_impl.h
View File

@ -115,6 +115,28 @@ static inline mbedtls_ct_uint_t mbedtls_ct_compiler_opaque(mbedtls_ct_uint_t x)
#endif
}
/*
* Selecting unified syntax is needed for gcc, and harmless on clang.
*
* This is needed because on Thumb 1, condition flags are always set, so
* e.g. "negs" is supported but "neg" is not (on Thumb 2, both exist).
*
* Under Thumb 1 unified syntax, only the "negs" form is accepted, and
* under divided syntax, only the "neg" form is accepted. clang only
* supports unified syntax.
*
* On Thumb 2 and Arm, both compilers are happy with the "s" suffix,
* although we don't actually care about setting the flags.
*
* For gcc, restore divided syntax afterwards - otherwise old versions of gcc
* seem to apply unified syntax globally, which breaks other asm code.
*/
#if !defined(__clang__)
#define RESTORE_ASM_SYNTAX ".syntax divided \n\t"
#else
#define RESTORE_ASM_SYNTAX
#endif
/* Convert a number into a condition in constant time. */
static inline mbedtls_ct_condition_t mbedtls_ct_bool(mbedtls_ct_uint_t x)
{
@ -140,28 +162,6 @@ static inline mbedtls_ct_condition_t mbedtls_ct_bool(mbedtls_ct_uint_t x)
return (mbedtls_ct_condition_t) x;
#elif defined(MBEDTLS_CT_ARM_ASM) && defined(MBEDTLS_CT_SIZE_32)
uint32_t s;
/*
* Selecting unified syntax is needed for gcc, and harmless on clang.
*
* This is needed because on Thumb 1, condition flags are always set, so
* e.g. "negs" is supported but "neg" is not (on Thumb 2, both exist).
*
* Under Thumb 1 unified syntax, only the "negs" form is accepted, and
* under divided syntax, only the "neg" form is accepted. clang only
* supports unified syntax.
*
* On Thumb 2 and Arm, both compilers are happy with the "s" suffix,
* although we don't actually care about setting the flags.
*
* For gcc, restore divided syntax afterwards - otherwise old versions of gcc
* seem to apply unified syntax globally, which breaks other asm code.
*/
#if !defined(__clang__)
#define RESTORE_ASM_SYNTAX ".syntax divided \n\t"
#else
#define RESTORE_ASM_SYNTAX
#endif
asm volatile (".syntax unified \n\t"
"negs %[s], %[x] \n\t"
"orrs %[x], %[x], %[s] \n\t"