| /* Copyright 2015, Kenneth MacKay. Licensed under the BSD 2-clause license. */ |
| |
| #ifndef _UECC_ASM_ARM_H_ |
| #define _UECC_ASM_ARM_H_ |
| |
| #if (uECC_SUPPORTS_secp256r1 || uECC_SUPPORTS_secp256k1) |
| #define uECC_MIN_WORDS 8 |
| #endif |
| #if uECC_SUPPORTS_secp224r1 |
| #undef uECC_MIN_WORDS |
| #define uECC_MIN_WORDS 7 |
| #endif |
| #if uECC_SUPPORTS_secp192r1 |
| #undef uECC_MIN_WORDS |
| #define uECC_MIN_WORDS 6 |
| #endif |
| #if uECC_SUPPORTS_secp160r1 |
| #undef uECC_MIN_WORDS |
| #define uECC_MIN_WORDS 5 |
| #endif |
| |
| #if (uECC_PLATFORM == uECC_arm_thumb) |
| #define REG_RW "+l" |
| #define REG_WRITE "=l" |
| #else |
| #define REG_RW "+r" |
| #define REG_WRITE "=r" |
| #endif |
| |
| #if (uECC_PLATFORM == uECC_arm_thumb || uECC_PLATFORM == uECC_arm_thumb2) |
| #define REG_RW_LO "+l" |
| #define REG_WRITE_LO "=l" |
| #else |
| #define REG_RW_LO "+r" |
| #define REG_WRITE_LO "=r" |
| #endif |
| |
| #if (uECC_PLATFORM == uECC_arm_thumb2) |
| #define RESUME_SYNTAX |
| #else |
| #define RESUME_SYNTAX ".syntax divided \n\t" |
| #endif |
| |
| #if (uECC_OPTIMIZATION_LEVEL >= 2) |
| |
| uECC_VLI_API uECC_word_t uECC_vli_add(uECC_word_t *result, |
| const uECC_word_t *left, |
| const uECC_word_t *right, |
| wordcount_t num_words) { |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| #if (uECC_PLATFORM == uECC_arm_thumb) || (uECC_PLATFORM == uECC_arm_thumb2) |
| uint32_t jump = (uECC_MAX_WORDS - num_words) * 4 * 2 + 1; |
| #else /* ARM */ |
| uint32_t jump = (uECC_MAX_WORDS - num_words) * 4 * 4; |
| #endif |
| #endif |
| uint32_t carry; |
| uint32_t left_word; |
| uint32_t right_word; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "movs %[carry], #0 \n\t" |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| "adr %[left], 1f \n\t" |
| ".align 4 \n\t" |
| "adds %[jump], %[left] \n\t" |
| #endif |
| |
| "ldmia %[lptr]!, {%[left]} \n\t" |
| "ldmia %[rptr]!, {%[right]} \n\t" |
| "adds %[left], %[right] \n\t" |
| "stmia %[dptr]!, {%[left]} \n\t" |
| |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| "bx %[jump] \n\t" |
| #endif |
| "1: \n\t" |
| REPEAT(DEC(uECC_MAX_WORDS), |
| "ldmia %[lptr]!, {%[left]} \n\t" |
| "ldmia %[rptr]!, {%[right]} \n\t" |
| "adcs %[left], %[right] \n\t" |
| "stmia %[dptr]!, {%[left]} \n\t") |
| |
| "adcs %[carry], %[carry] \n\t" |
| RESUME_SYNTAX |
| : [dptr] REG_RW_LO (result), [lptr] REG_RW_LO (left), [rptr] REG_RW_LO (right), |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| [jump] REG_RW_LO (jump), |
| #endif |
| [carry] REG_WRITE_LO (carry), [left] REG_WRITE_LO (left_word), |
| [right] REG_WRITE_LO (right_word) |
| : |
| : "cc", "memory" |
| ); |
| return carry; |
| } |
| #define asm_add 1 |
| |
| uECC_VLI_API uECC_word_t uECC_vli_sub(uECC_word_t *result, |
| const uECC_word_t *left, |
| const uECC_word_t *right, |
| wordcount_t num_words) { |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| #if (uECC_PLATFORM == uECC_arm_thumb) || (uECC_PLATFORM == uECC_arm_thumb2) |
| uint32_t jump = (uECC_MAX_WORDS - num_words) * 4 * 2 + 1; |
| #else /* ARM */ |
| uint32_t jump = (uECC_MAX_WORDS - num_words) * 4 * 4; |
| #endif |
| #endif |
| uint32_t carry; |
| uint32_t left_word; |
| uint32_t right_word; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "movs %[carry], #0 \n\t" |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| "adr %[left], 1f \n\t" |
| ".align 4 \n\t" |
| "adds %[jump], %[left] \n\t" |
| #endif |
| |
| "ldmia %[lptr]!, {%[left]} \n\t" |
| "ldmia %[rptr]!, {%[right]} \n\t" |
| "subs %[left], %[right] \n\t" |
| "stmia %[dptr]!, {%[left]} \n\t" |
| |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| "bx %[jump] \n\t" |
| #endif |
| "1: \n\t" |
| REPEAT(DEC(uECC_MAX_WORDS), |
| "ldmia %[lptr]!, {%[left]} \n\t" |
| "ldmia %[rptr]!, {%[right]} \n\t" |
| "sbcs %[left], %[right] \n\t" |
| "stmia %[dptr]!, {%[left]} \n\t") |
| |
| "adcs %[carry], %[carry] \n\t" |
| RESUME_SYNTAX |
| : [dptr] REG_RW_LO (result), [lptr] REG_RW_LO (left), [rptr] REG_RW_LO (right), |
| #if (uECC_MAX_WORDS != uECC_MIN_WORDS) |
| [jump] REG_RW_LO (jump), |
| #endif |
| [carry] REG_WRITE_LO (carry), [left] REG_WRITE_LO (left_word), |
| [right] REG_WRITE_LO (right_word) |
| : |
| : "cc", "memory" |
| ); |
| return !carry; /* Note that on ARM, carry flag set means "no borrow" when subtracting |
| (for some reason...) */ |
| } |
| #define asm_sub 1 |
| |
| #endif /* (uECC_OPTIMIZATION_LEVEL >= 2) */ |
| |
| #if (uECC_OPTIMIZATION_LEVEL >= 3) |
| |
| #if (uECC_PLATFORM != uECC_arm_thumb) |
| |
| #if uECC_ARM_USE_UMAAL |
| #include "asm_arm_mult_square_umaal.inc" |
| #else |
| #include "asm_arm_mult_square.inc" |
| #endif |
| |
| #if (uECC_OPTIMIZATION_LEVEL == 3) |
| |
| uECC_VLI_API void uECC_vli_mult(uint32_t *result, |
| const uint32_t *left, |
| const uint32_t *right, |
| wordcount_t num_words) { |
| register uint32_t *r0 __asm__("r0") = result; |
| register const uint32_t *r1 __asm__("r1") = left; |
| register const uint32_t *r2 __asm__("r2") = right; |
| register uint32_t r3 __asm__("r3") = num_words; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| #if (uECC_MIN_WORDS == 5) |
| FAST_MULT_ASM_5 |
| #if (uECC_MAX_WORDS > 5) |
| FAST_MULT_ASM_5_TO_6 |
| #endif |
| #if (uECC_MAX_WORDS > 6) |
| FAST_MULT_ASM_6_TO_7 |
| #endif |
| #if (uECC_MAX_WORDS > 7) |
| FAST_MULT_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 6) |
| FAST_MULT_ASM_6 |
| #if (uECC_MAX_WORDS > 6) |
| FAST_MULT_ASM_6_TO_7 |
| #endif |
| #if (uECC_MAX_WORDS > 7) |
| FAST_MULT_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 7) |
| FAST_MULT_ASM_7 |
| #if (uECC_MAX_WORDS > 7) |
| FAST_MULT_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 8) |
| FAST_MULT_ASM_8 |
| #endif |
| "1: \n\t" |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1), "+r" (r2) |
| : "r" (r3) |
| : "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| } |
| #define asm_mult 1 |
| |
| #if uECC_SQUARE_FUNC |
| uECC_VLI_API void uECC_vli_square(uECC_word_t *result, |
| const uECC_word_t *left, |
| wordcount_t num_words) { |
| register uint32_t *r0 __asm__("r0") = result; |
| register const uint32_t *r1 __asm__("r1") = left; |
| register uint32_t r2 __asm__("r2") = num_words; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| #if (uECC_MIN_WORDS == 5) |
| FAST_SQUARE_ASM_5 |
| #if (uECC_MAX_WORDS > 5) |
| FAST_SQUARE_ASM_5_TO_6 |
| #endif |
| #if (uECC_MAX_WORDS > 6) |
| FAST_SQUARE_ASM_6_TO_7 |
| #endif |
| #if (uECC_MAX_WORDS > 7) |
| FAST_SQUARE_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 6) |
| FAST_SQUARE_ASM_6 |
| #if (uECC_MAX_WORDS > 6) |
| FAST_SQUARE_ASM_6_TO_7 |
| #endif |
| #if (uECC_MAX_WORDS > 7) |
| FAST_SQUARE_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 7) |
| FAST_SQUARE_ASM_7 |
| #if (uECC_MAX_WORDS > 7) |
| FAST_SQUARE_ASM_7_TO_8 |
| #endif |
| #elif (uECC_MIN_WORDS == 8) |
| FAST_SQUARE_ASM_8 |
| #endif |
| |
| "1: \n\t" |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1) |
| : "r" (r2) |
| : "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| } |
| #define asm_square 1 |
| #endif /* uECC_SQUARE_FUNC */ |
| |
| #else /* (uECC_OPTIMIZATION_LEVEL > 3) */ |
| |
| uECC_VLI_API void uECC_vli_mult(uint32_t *result, |
| const uint32_t *left, |
| const uint32_t *right, |
| wordcount_t num_words) { |
| register uint32_t *r0 __asm__("r0") = result; |
| register const uint32_t *r1 __asm__("r1") = left; |
| register const uint32_t *r2 __asm__("r2") = right; |
| register uint32_t r3 __asm__("r3") = num_words; |
| |
| #if uECC_SUPPORTS_secp160r1 |
| if (num_words == 5) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_MULT_ASM_5 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1), "+r" (r2) |
| : "r" (r3) |
| : "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if uECC_SUPPORTS_secp192r1 |
| if (num_words == 6) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_MULT_ASM_6 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1), "+r" (r2) |
| : "r" (r3) |
| : "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if uECC_SUPPORTS_secp224r1 |
| if (num_words == 7) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_MULT_ASM_7 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1), "+r" (r2) |
| : "r" (r3) |
| : "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if (uECC_SUPPORTS_secp256r1 || uECC_SUPPORTS_secp256k1) |
| if (num_words == 8) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_MULT_ASM_8 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1), "+r" (r2) |
| : "r" (r3) |
| : "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| } |
| #define asm_mult 1 |
| |
| #if uECC_SQUARE_FUNC |
| uECC_VLI_API void uECC_vli_square(uECC_word_t *result, |
| const uECC_word_t *left, |
| wordcount_t num_words) { |
| register uint32_t *r0 __asm__("r0") = result; |
| register const uint32_t *r1 __asm__("r1") = left; |
| register uint32_t r2 __asm__("r2") = num_words; |
| |
| #if uECC_SUPPORTS_secp160r1 |
| if (num_words == 5) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_SQUARE_ASM_5 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1) |
| : "r" (r2) |
| : "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if uECC_SUPPORTS_secp192r1 |
| if (num_words == 6) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_SQUARE_ASM_6 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1) |
| : "r" (r2) |
| : "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if uECC_SUPPORTS_secp224r1 |
| if (num_words == 7) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_SQUARE_ASM_7 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1) |
| : "r" (r2) |
| : "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| #if (uECC_SUPPORTS_secp256r1 || uECC_SUPPORTS_secp256k1) |
| if (num_words == 8) { |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| FAST_SQUARE_ASM_8 |
| RESUME_SYNTAX |
| : "+r" (r0), "+r" (r1) |
| : "r" (r2) |
| : "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| return; |
| } |
| #endif |
| } |
| #define asm_square 1 |
| #endif /* uECC_SQUARE_FUNC */ |
| |
| #endif /* (uECC_OPTIMIZATION_LEVEL > 3) */ |
| |
| #endif /* uECC_PLATFORM != uECC_arm_thumb */ |
| |
| #endif /* (uECC_OPTIMIZATION_LEVEL >= 3) */ |
| |
| /* ---- "Small" implementations ---- */ |
| |
| #if !asm_add |
| uECC_VLI_API uECC_word_t uECC_vli_add(uECC_word_t *result, |
| const uECC_word_t *left, |
| const uECC_word_t *right, |
| wordcount_t num_words) { |
| uint32_t carry = 0; |
| uint32_t left_word; |
| uint32_t right_word; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "1: \n\t" |
| "ldmia %[lptr]!, {%[left]} \n\t" /* Load left word. */ |
| "ldmia %[rptr]!, {%[right]} \n\t" /* Load right word. */ |
| "lsrs %[carry], #1 \n\t" /* Set up carry flag (carry = 0 after this). */ |
| "adcs %[left], %[left], %[right] \n\t" /* Add with carry. */ |
| "adcs %[carry], %[carry], %[carry] \n\t" /* Store carry bit. */ |
| "stmia %[dptr]!, {%[left]} \n\t" /* Store result word. */ |
| "subs %[ctr], #1 \n\t" /* Decrement counter. */ |
| "bne 1b \n\t" /* Loop until counter == 0. */ |
| RESUME_SYNTAX |
| : [dptr] REG_RW (result), [lptr] REG_RW (left), [rptr] REG_RW (right), |
| [ctr] REG_RW (num_words), [carry] REG_RW (carry), |
| [left] REG_WRITE (left_word), [right] REG_WRITE (right_word) |
| : |
| : "cc", "memory" |
| ); |
| return carry; |
| } |
| #define asm_add 1 |
| #endif |
| |
| #if !asm_sub |
| uECC_VLI_API uECC_word_t uECC_vli_sub(uECC_word_t *result, |
| const uECC_word_t *left, |
| const uECC_word_t *right, |
| wordcount_t num_words) { |
| uint32_t carry = 1; /* carry = 1 initially (means don't borrow) */ |
| uint32_t left_word; |
| uint32_t right_word; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "1: \n\t" |
| "ldmia %[lptr]!, {%[left]} \n\t" /* Load left word. */ |
| "ldmia %[rptr]!, {%[right]} \n\t" /* Load right word. */ |
| "lsrs %[carry], #1 \n\t" /* Set up carry flag (carry = 0 after this). */ |
| "sbcs %[left], %[left], %[right] \n\t" /* Subtract with borrow. */ |
| "adcs %[carry], %[carry], %[carry] \n\t" /* Store carry bit. */ |
| "stmia %[dptr]!, {%[left]} \n\t" /* Store result word. */ |
| "subs %[ctr], #1 \n\t" /* Decrement counter. */ |
| "bne 1b \n\t" /* Loop until counter == 0. */ |
| RESUME_SYNTAX |
| : [dptr] REG_RW (result), [lptr] REG_RW (left), [rptr] REG_RW (right), |
| [ctr] REG_RW (num_words), [carry] REG_RW (carry), |
| [left] REG_WRITE (left_word), [right] REG_WRITE (right_word) |
| : |
| : "cc", "memory" |
| ); |
| return !carry; |
| } |
| #define asm_sub 1 |
| #endif |
| |
| #if !asm_mult |
| uECC_VLI_API void uECC_vli_mult(uECC_word_t *result, |
| const uECC_word_t *left, |
| const uECC_word_t *right, |
| wordcount_t num_words) { |
| #if (uECC_PLATFORM != uECC_arm_thumb) |
| uint32_t c0 = 0; |
| uint32_t c1 = 0; |
| uint32_t c2 = 0; |
| uint32_t k = 0; |
| uint32_t i; |
| uint32_t t0, t1; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| |
| "1: \n\t" /* outer loop (k < num_words) */ |
| "movs %[i], #0 \n\t" /* i = 0 */ |
| "b 3f \n\t" |
| |
| "2: \n\t" /* outer loop (k >= num_words) */ |
| "movs %[i], %[k] \n\t" /* i = k */ |
| "subs %[i], %[last_word] \n\t" /* i = k - (num_words - 1) (times 4) */ |
| |
| "3: \n\t" /* inner loop */ |
| "subs %[t0], %[k], %[i] \n\t" /* t0 = k-i */ |
| |
| "ldr %[t1], [%[right], %[t0]] \n\t" /* t1 = right[k - i] */ |
| "ldr %[t0], [%[left], %[i]] \n\t" /* t0 = left[i] */ |
| |
| "umull %[t0], %[t1], %[t0], %[t1] \n\t" /* (t0, t1) = left[i] * right[k - i] */ |
| |
| "adds %[c0], %[c0], %[t0] \n\t" /* add low word to c0 */ |
| "adcs %[c1], %[c1], %[t1] \n\t" /* add high word to c1, including carry */ |
| "adcs %[c2], %[c2], #0 \n\t" /* add carry to c2 */ |
| |
| "adds %[i], #4 \n\t" /* i += 4 */ |
| "cmp %[i], %[last_word] \n\t" /* i > (num_words - 1) (times 4)? */ |
| "bgt 4f \n\t" /* if so, exit the loop */ |
| "cmp %[i], %[k] \n\t" /* i <= k? */ |
| "ble 3b \n\t" /* if so, continue looping */ |
| |
| "4: \n\t" /* end inner loop */ |
| |
| "str %[c0], [%[result], %[k]] \n\t" /* result[k] = c0 */ |
| "mov %[c0], %[c1] \n\t" /* c0 = c1 */ |
| "mov %[c1], %[c2] \n\t" /* c1 = c2 */ |
| "movs %[c2], #0 \n\t" /* c2 = 0 */ |
| "adds %[k], #4 \n\t" /* k += 4 */ |
| "cmp %[k], %[last_word] \n\t" /* k <= (num_words - 1) (times 4) ? */ |
| "ble 1b \n\t" /* if so, loop back, start with i = 0 */ |
| "cmp %[k], %[last_word], lsl #1 \n\t" /* k <= (num_words * 2 - 2) (times 4) ? */ |
| "ble 2b \n\t" /* if so, loop back, start with i = (k + 1) - num_words */ |
| /* end outer loop */ |
| |
| "str %[c0], [%[result], %[k]] \n\t" /* result[num_words * 2 - 1] = c0 */ |
| RESUME_SYNTAX |
| : [c0] "+r" (c0), [c1] "+r" (c1), [c2] "+r" (c2), |
| [k] "+r" (k), [i] "=&r" (i), [t0] "=&r" (t0), [t1] "=&r" (t1) |
| : [result] "r" (result), [left] "r" (left), [right] "r" (right), |
| [last_word] "r" ((num_words - 1) * 4) |
| : "cc", "memory" |
| ); |
| |
| #else /* Thumb-1 */ |
| uint32_t r4, r5, r6, r7; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "subs %[r3], #1 \n\t" /* r3 = num_words - 1 */ |
| "lsls %[r3], #2 \n\t" /* r3 = (num_words - 1) * 4 */ |
| "mov r8, %[r3] \n\t" /* r8 = (num_words - 1) * 4 */ |
| "lsls %[r3], #1 \n\t" /* r3 = (num_words - 1) * 8 */ |
| "mov r9, %[r3] \n\t" /* r9 = (num_words - 1) * 8 */ |
| "movs %[r3], #0 \n\t" /* c0 = 0 */ |
| "movs %[r4], #0 \n\t" /* c1 = 0 */ |
| "movs %[r5], #0 \n\t" /* c2 = 0 */ |
| "movs %[r6], #0 \n\t" /* k = 0 */ |
| |
| "push {%[r0]} \n\t" /* keep result on the stack */ |
| |
| "1: \n\t" /* outer loop (k < num_words) */ |
| "movs %[r7], #0 \n\t" /* r7 = i = 0 */ |
| "b 3f \n\t" |
| |
| "2: \n\t" /* outer loop (k >= num_words) */ |
| "movs %[r7], %[r6] \n\t" /* r7 = k */ |
| "mov %[r0], r8 \n\t" /* r0 = (num_words - 1) * 4 */ |
| "subs %[r7], %[r0] \n\t" /* r7 = i = k - (num_words - 1) (times 4) */ |
| |
| "3: \n\t" /* inner loop */ |
| "mov r10, %[r3] \n\t" |
| "mov r11, %[r4] \n\t" |
| "mov r12, %[r5] \n\t" |
| "mov r14, %[r6] \n\t" |
| "subs %[r0], %[r6], %[r7] \n\t" /* r0 = k - i */ |
| |
| "ldr %[r4], [%[r2], %[r0]] \n\t" /* r4 = right[k - i] */ |
| "ldr %[r0], [%[r1], %[r7]] \n\t" /* r0 = left[i] */ |
| |
| "lsrs %[r3], %[r0], #16 \n\t" /* r3 = a1 */ |
| "uxth %[r0], %[r0] \n\t" /* r0 = a0 */ |
| |
| "lsrs %[r5], %[r4], #16 \n\t" /* r5 = b1 */ |
| "uxth %[r4], %[r4] \n\t" /* r4 = b0 */ |
| |
| "movs %[r6], %[r3] \n\t" /* r6 = a1 */ |
| "muls %[r6], %[r5], %[r6] \n\t" /* r6 = a1 * b1 */ |
| "muls %[r3], %[r4], %[r3] \n\t" /* r3 = b0 * a1 */ |
| "muls %[r5], %[r0], %[r5] \n\t" /* r5 = a0 * b1 */ |
| "muls %[r0], %[r4], %[r0] \n\t" /* r0 = a0 * b0 */ |
| |
| /* Add middle terms */ |
| "lsls %[r4], %[r3], #16 \n\t" |
| "lsrs %[r3], %[r3], #16 \n\t" |
| "adds %[r0], %[r4] \n\t" |
| "adcs %[r6], %[r3] \n\t" |
| |
| "lsls %[r4], %[r5], #16 \n\t" |
| "lsrs %[r5], %[r5], #16 \n\t" |
| "adds %[r0], %[r4] \n\t" |
| "adcs %[r6], %[r5] \n\t" |
| |
| "mov %[r3], r10\n\t" |
| "mov %[r4], r11\n\t" |
| "mov %[r5], r12\n\t" |
| "adds %[r3], %[r0] \n\t" /* add low word to c0 */ |
| "adcs %[r4], %[r6] \n\t" /* add high word to c1, including carry */ |
| "movs %[r0], #0 \n\t" /* r0 = 0 (does not affect carry bit) */ |
| "adcs %[r5], %[r0] \n\t" /* add carry to c2 */ |
| |
| "mov %[r6], r14\n\t" /* r6 = k */ |
| |
| "adds %[r7], #4 \n\t" /* i += 4 */ |
| "cmp %[r7], r8 \n\t" /* i > (num_words - 1) (times 4)? */ |
| "bgt 4f \n\t" /* if so, exit the loop */ |
| "cmp %[r7], %[r6] \n\t" /* i <= k? */ |
| "ble 3b \n\t" /* if so, continue looping */ |
| |
| "4: \n\t" /* end inner loop */ |
| |
| "ldr %[r0], [sp, #0] \n\t" /* r0 = result */ |
| |
| "str %[r3], [%[r0], %[r6]] \n\t" /* result[k] = c0 */ |
| "mov %[r3], %[r4] \n\t" /* c0 = c1 */ |
| "mov %[r4], %[r5] \n\t" /* c1 = c2 */ |
| "movs %[r5], #0 \n\t" /* c2 = 0 */ |
| "adds %[r6], #4 \n\t" /* k += 4 */ |
| "cmp %[r6], r8 \n\t" /* k <= (num_words - 1) (times 4) ? */ |
| "ble 1b \n\t" /* if so, loop back, start with i = 0 */ |
| "cmp %[r6], r9 \n\t" /* k <= (num_words * 2 - 2) (times 4) ? */ |
| "ble 2b \n\t" /* if so, loop back, with i = (k + 1) - num_words */ |
| /* end outer loop */ |
| |
| "str %[r3], [%[r0], %[r6]] \n\t" /* result[num_words * 2 - 1] = c0 */ |
| "pop {%[r0]} \n\t" /* pop result off the stack */ |
| |
| ".syntax divided \n\t" |
| : [r3] "+l" (num_words), [r4] "=&l" (r4), |
| [r5] "=&l" (r5), [r6] "=&l" (r6), [r7] "=&l" (r7) |
| : [r0] "l" (result), [r1] "l" (left), [r2] "l" (right) |
| : "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| #endif |
| } |
| #define asm_mult 1 |
| #endif |
| |
| #if uECC_SQUARE_FUNC |
| #if !asm_square |
| uECC_VLI_API void uECC_vli_square(uECC_word_t *result, |
| const uECC_word_t *left, |
| wordcount_t num_words) { |
| #if (uECC_PLATFORM != uECC_arm_thumb) |
| uint32_t c0 = 0; |
| uint32_t c1 = 0; |
| uint32_t c2 = 0; |
| uint32_t k = 0; |
| uint32_t i, tt; |
| uint32_t t0, t1; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| |
| "1: \n\t" /* outer loop (k < num_words) */ |
| "movs %[i], #0 \n\t" /* i = 0 */ |
| "b 3f \n\t" |
| |
| "2: \n\t" /* outer loop (k >= num_words) */ |
| "movs %[i], %[k] \n\t" /* i = k */ |
| "subs %[i], %[last_word] \n\t" /* i = k - (num_words - 1) (times 4) */ |
| |
| "3: \n\t" /* inner loop */ |
| "subs %[tt], %[k], %[i] \n\t" /* tt = k-i */ |
| |
| "ldr %[t1], [%[left], %[tt]] \n\t" /* t1 = left[k - i] */ |
| "ldr %[t0], [%[left], %[i]] \n\t" /* t0 = left[i] */ |
| |
| "umull %[t0], %[t1], %[t0], %[t1] \n\t" /* (t0, t1) = left[i] * right[k - i] */ |
| |
| "cmp %[i], %[tt] \n\t" /* (i < k - i) ? */ |
| "bge 4f \n\t" /* if i >= k - i, skip */ |
| "adds %[c0], %[c0], %[t0] \n\t" /* add low word to c0 */ |
| "adcs %[c1], %[c1], %[t1] \n\t" /* add high word to c1, including carry */ |
| "adcs %[c2], %[c2], #0 \n\t" /* add carry to c2 */ |
| |
| "4: \n\t" |
| "adds %[c0], %[c0], %[t0] \n\t" /* add low word to c0 */ |
| "adcs %[c1], %[c1], %[t1] \n\t" /* add high word to c1, including carry */ |
| "adcs %[c2], %[c2], #0 \n\t" /* add carry to c2 */ |
| |
| "adds %[i], #4 \n\t" /* i += 4 */ |
| "cmp %[i], %[k] \n\t" /* i >= k? */ |
| "bge 5f \n\t" /* if so, exit the loop */ |
| "subs %[tt], %[k], %[i] \n\t" /* tt = k - i */ |
| "cmp %[i], %[tt] \n\t" /* i <= k - i? */ |
| "ble 3b \n\t" /* if so, continue looping */ |
| |
| "5: \n\t" /* end inner loop */ |
| |
| "str %[c0], [%[result], %[k]] \n\t" /* result[k] = c0 */ |
| "mov %[c0], %[c1] \n\t" /* c0 = c1 */ |
| "mov %[c1], %[c2] \n\t" /* c1 = c2 */ |
| "movs %[c2], #0 \n\t" /* c2 = 0 */ |
| "adds %[k], #4 \n\t" /* k += 4 */ |
| "cmp %[k], %[last_word] \n\t" /* k <= (num_words - 1) (times 4) ? */ |
| "ble 1b \n\t" /* if so, loop back, start with i = 0 */ |
| "cmp %[k], %[last_word], lsl #1 \n\t" /* k <= (num_words * 2 - 2) (times 4) ? */ |
| "ble 2b \n\t" /* if so, loop back, start with i = (k + 1) - num_words */ |
| /* end outer loop */ |
| |
| "str %[c0], [%[result], %[k]] \n\t" /* result[num_words * 2 - 1] = c0 */ |
| RESUME_SYNTAX |
| : [c0] "+r" (c0), [c1] "+r" (c1), [c2] "+r" (c2), |
| [k] "+r" (k), [i] "=&r" (i), [tt] "=&r" (tt), [t0] "=&r" (t0), [t1] "=&r" (t1) |
| : [result] "r" (result), [left] "r" (left), [last_word] "r" ((num_words - 1) * 4) |
| : "cc", "memory" |
| ); |
| |
| #else |
| uint32_t r3, r4, r5, r6, r7; |
| |
| __asm__ volatile ( |
| ".syntax unified \n\t" |
| "subs %[r2], #1 \n\t" /* r2 = num_words - 1 */ |
| "lsls %[r2], #2 \n\t" /* r2 = (num_words - 1) * 4 */ |
| "mov r8, %[r2] \n\t" /* r8 = (num_words - 1) * 4 */ |
| "lsls %[r2], #1 \n\t" /* r2 = (num_words - 1) * 8 */ |
| "mov r9, %[r2] \n\t" /* r9 = (num_words - 1) * 8 */ |
| "movs %[r2], #0 \n\t" /* c0 = 0 */ |
| "movs %[r3], #0 \n\t" /* c1 = 0 */ |
| "movs %[r4], #0 \n\t" /* c2 = 0 */ |
| "movs %[r5], #0 \n\t" /* k = 0 */ |
| |
| "push {%[r0]} \n\t" /* keep result on the stack */ |
| |
| "1: \n\t" /* outer loop (k < num_words) */ |
| "movs %[r6], #0 \n\t" /* r6 = i = 0 */ |
| "b 3f \n\t" |
| |
| "2: \n\t" /* outer loop (k >= num_words) */ |
| "movs %[r6], %[r5] \n\t" /* r6 = k */ |
| "mov %[r0], r8 \n\t" /* r0 = (num_words - 1) * 4 */ |
| "subs %[r6], %[r0] \n\t" /* r6 = i = k - (num_words - 1) (times 4) */ |
| |
| "3: \n\t" /* inner loop */ |
| "mov r10, %[r2] \n\t" |
| "mov r11, %[r3] \n\t" |
| "mov r12, %[r4] \n\t" |
| "mov r14, %[r5] \n\t" |
| "subs %[r7], %[r5], %[r6] \n\t" /* r7 = k - i */ |
| |
| "ldr %[r3], [%[r1], %[r7]] \n\t" /* r3 = left[k - i] */ |
| "ldr %[r0], [%[r1], %[r6]] \n\t" /* r0 = left[i] */ |
| |
| "lsrs %[r2], %[r0], #16 \n\t" /* r2 = a1 */ |
| "uxth %[r0], %[r0] \n\t" /* r0 = a0 */ |
| |
| "lsrs %[r4], %[r3], #16 \n\t" /* r4 = b1 */ |
| "uxth %[r3], %[r3] \n\t" /* r3 = b0 */ |
| |
| "movs %[r5], %[r2] \n\t" /* r5 = a1 */ |
| "muls %[r5], %[r4], %[r5] \n\t" /* r5 = a1 * b1 */ |
| "muls %[r2], %[r3], %[r2] \n\t" /* r2 = b0 * a1 */ |
| "muls %[r4], %[r0], %[r4] \n\t" /* r4 = a0 * b1 */ |
| "muls %[r0], %[r3], %[r0] \n\t" /* r0 = a0 * b0 */ |
| |
| /* Add middle terms */ |
| "lsls %[r3], %[r2], #16 \n\t" |
| "lsrs %[r2], %[r2], #16 \n\t" |
| "adds %[r0], %[r3] \n\t" |
| "adcs %[r5], %[r2] \n\t" |
| |
| "lsls %[r3], %[r4], #16 \n\t" |
| "lsrs %[r4], %[r4], #16 \n\t" |
| "adds %[r0], %[r3] \n\t" |
| "adcs %[r5], %[r4] \n\t" |
| |
| /* Add to acc, doubling if necessary */ |
| "mov %[r2], r10\n\t" |
| "mov %[r3], r11\n\t" |
| "mov %[r4], r12\n\t" |
| |
| "cmp %[r6], %[r7] \n\t" /* (i < k - i) ? */ |
| "bge 4f \n\t" /* if i >= k - i, skip */ |
| "movs %[r7], #0 \n\t" /* r7 = 0 */ |
| "adds %[r2], %[r0] \n\t" /* add low word to c0 */ |
| "adcs %[r3], %[r5] \n\t" /* add high word to c1, including carry */ |
| "adcs %[r4], %[r7] \n\t" /* add carry to c2 */ |
| "4: \n\t" |
| "movs %[r7], #0 \n\t" /* r7 = 0 */ |
| "adds %[r2], %[r0] \n\t" /* add low word to c0 */ |
| "adcs %[r3], %[r5] \n\t" /* add high word to c1, including carry */ |
| "adcs %[r4], %[r7] \n\t" /* add carry to c2 */ |
| |
| "mov %[r5], r14\n\t" /* r5 = k */ |
| |
| "adds %[r6], #4 \n\t" /* i += 4 */ |
| "cmp %[r6], %[r5] \n\t" /* i >= k? */ |
| "bge 5f \n\t" /* if so, exit the loop */ |
| "subs %[r7], %[r5], %[r6] \n\t" /* r7 = k - i */ |
| "cmp %[r6], %[r7] \n\t" /* i <= k - i? */ |
| "ble 3b \n\t" /* if so, continue looping */ |
| |
| "5: \n\t" /* end inner loop */ |
| |
| "ldr %[r0], [sp, #0] \n\t" /* r0 = result */ |
| |
| "str %[r2], [%[r0], %[r5]] \n\t" /* result[k] = c0 */ |
| "mov %[r2], %[r3] \n\t" /* c0 = c1 */ |
| "mov %[r3], %[r4] \n\t" /* c1 = c2 */ |
| "movs %[r4], #0 \n\t" /* c2 = 0 */ |
| "adds %[r5], #4 \n\t" /* k += 4 */ |
| "cmp %[r5], r8 \n\t" /* k <= (num_words - 1) (times 4) ? */ |
| "ble 1b \n\t" /* if so, loop back, start with i = 0 */ |
| "cmp %[r5], r9 \n\t" /* k <= (num_words * 2 - 2) (times 4) ? */ |
| "ble 2b \n\t" /* if so, loop back, with i = (k + 1) - num_words */ |
| /* end outer loop */ |
| |
| "str %[r2], [%[r0], %[r5]] \n\t" /* result[num_words * 2 - 1] = c0 */ |
| "pop {%[r0]} \n\t" /* pop result off the stack */ |
| |
| ".syntax divided \n\t" |
| : [r2] "+l" (num_words), [r3] "=&l" (r3), [r4] "=&l" (r4), |
| [r5] "=&l" (r5), [r6] "=&l" (r6), [r7] "=&l" (r7) |
| : [r0] "l" (result), [r1] "l" (left) |
| : "r8", "r9", "r10", "r11", "r12", "r14", "cc", "memory" |
| ); |
| #endif |
| } |
| #define asm_square 1 |
| #endif |
| #endif /* uECC_SQUARE_FUNC */ |
| |
| #endif /* _UECC_ASM_ARM_H_ */ |
