diff options
| -rw-r--r-- | networking/tls_sp_c32.c | 84 |
1 files changed, 82 insertions, 2 deletions
diff --git a/networking/tls_sp_c32.c b/networking/tls_sp_c32.c index b999518..e1c4cdd 100644 --- a/networking/tls_sp_c32.c +++ b/networking/tls_sp_c32.c @@ -294,6 +294,85 @@ static int sp_256_sub_8(sp_digit* r, const sp_digit* a, const sp_digit* b) /* Multiply a and b into r. (r = a * b) */ static void sp_256_mul_8(sp_digit* r, const sp_digit* a, const sp_digit* b) { +#if ALLOW_ASM && defined(__GNUC__) && defined(__i386__) + sp_digit rr[15]; /* in case r coincides with a or b */ + int k; + uint32_t accl; + uint32_t acch; + + acch = accl = 0; + for (k = 0; k < 15; k++) { + int i, j; + uint32_t acc_hi; + i = k - 7; + if (i < 0) + i = 0; + j = k - i; + acc_hi = 0; + do { +//////////////////////// +// uint64_t m = ((uint64_t)a[i]) * b[j]; +// acc_hi:acch:accl += m; + asm volatile ( + // a[i] is already loaded in %%eax +"\n mull %7" +"\n addl %%eax, %0" +"\n adcl %%edx, %1" +"\n adcl $0, %2" + : "=rm" (accl), "=rm" (acch), "=rm" (acc_hi) + : "0" (accl), "1" (acch), "2" (acc_hi), "a" (a[i]), "m" (b[j]) + : "cc", "dx" + ); +//////////////////////// + j--; + i++; + } while (i != 8 && i <= k); + rr[k] = accl; + accl = acch; + acch = acc_hi; + } + r[15] = accl; + memcpy(r, rr, sizeof(rr)); +#elif 0 + //TODO: arm assembly (untested) + sp_digit tmp[16]; + + asm volatile ( +"\n mov r5, #0" +"\n mov r6, #0" +"\n mov r7, #0" +"\n mov r8, #0" +"\n 1:" +"\n subs r3, r5, #28" +"\n movcc r3, #0" +"\n sub r4, r5, r3" +"\n 2:" +"\n ldr r14, [%[a], r3]" +"\n ldr r12, [%[b], r4]" +"\n umull r9, r10, r14, r12" +"\n adds r6, r6, r9" +"\n adcs r7, r7, r10" +"\n adc r8, r8, #0" +"\n add r3, r3, #4" +"\n sub r4, r4, #4" +"\n cmp r3, #32" +"\n beq 3f" +"\n cmp r3, r5" +"\n ble 2b" +"\n 3:" +"\n str r6, [%[r], r5]" +"\n mov r6, r7" +"\n mov r7, r8" +"\n mov r8, #0" +"\n add r5, r5, #4" +"\n cmp r5, #56" +"\n ble 1b" +"\n str r6, [%[r], r5]" + : [r] "r" (tmp), [a] "r" (a), [b] "r" (b) + : "memory", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r14", "r12" + ); + memcpy(r, tmp, sizeof(tmp)); +#else sp_digit rr[15]; /* in case r coincides with a or b */ int i, j, k; uint64_t acc; @@ -306,19 +385,20 @@ static void sp_256_mul_8(sp_digit* r, const sp_digit* a, const sp_digit* b) i = 0; j = k - i; acc_hi = 0; - while (i != 8 && i <= k) { + do { uint64_t m = ((uint64_t)a[i]) * b[j]; acc += m; if (acc < m) acc_hi++; j--; i++; - } + } while (i != 8 && i <= k); rr[k] = acc; acc = (acc >> 32) | ((uint64_t)acc_hi << 32); } r[15] = acc; memcpy(r, rr, sizeof(rr)); +#endif } /* Shift number right one bit. Bottom bit is lost. */ |