PSA global data: move fields around to save code size
Move fields around to have fewer accesses outside the 128-element Thumb
direct access window.
In psa_crypto.c's global_data, put the state fields first (-20).
In psa_crypto_slot_management.c's global_data, keep the key slots first
(otherwise it's +24).
In mbedtls_psa_random_context_t, swapping entropy and drbg makes no
difference (at least when the DRBG is mbedtls_ctr_drbg_context).
Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/psa_crypto.o: 16166 -> 16146 (diff: 20)
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 406e6c4..e85bbb8 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -108,9 +108,9 @@
typedef struct
{
- mbedtls_psa_random_context_t rng;
unsigned initialized : 1;
unsigned rng_state : 2;
+ mbedtls_psa_random_context_t rng;
} psa_global_data_t;
static psa_global_data_t global_data;