I have this functions, the result is correct but the compiler don't vectorize this.How can I achive that the compiler vectorize this and how can I optimize this codes?
void LongNumSet( char *L, unsigned N, char digit ){ for (int i = 0; i < N; ++i){ L[i] = digit; }}void LongNumCopy( char *Vin, char *Vout, unsigned N ){ for ( int i=0; i< N; ++i ) { Vout[i] = Vin[i]; }}char LongNumAddition( char *__restrict Vin1, char * __restrict Vin2, char * __restrict Vout, unsigned N ){ char CARRY = 0,R,aux; Vin1 = (char*)__builtin_assume_aligned (Vin1, 1); Vin2 = (char*)__builtin_assume_aligned (Vin2, 1); for ( int i=0; i< N; ++i ) { char R = Vin1[i] + Vin2[i] + CARRY; aux = R <= 9; Vout[i] = (aux) ? R:R-ten; CARRY = (aux) ? 0:1; } return CARRY;}char LongNumAddDigit( char *V, char digit, unsigned N ){ int i=0; char R = V[0] + digit; if ( R < ten){ V[0] = R; return 0; } V[0] = R-ten; // add carry, maybe iteratively for all digits char CARRY = 1; i = 1; while ( CARRY && i < N ) { if ( V[i] < 9 ) { V[i]++; CARRY = 0; } else { V[i] = 0; i++; // CARRY remains set to 1 } } return CARRY;}I use the comand gcc -O3 -ffast-math -msse -funroll-all-loops -ftree-vectorizer-verbose=25 -lm -g $1 -o ${2}.O3 and I executate the program in 55 s.This is all of code:
#include <stdio.h>#include <stdlib.h>#include <stdint.h>// Variable used to generate pseudo-random numbersunsigned int seed;unsigned int temp;unsigned int var1 = 214013;unsigned int var2 = 2531011;#define val13 13#define ten 10// Function to generate pseudo-random numbersinline int myRandom() { temp = var1*seed; seed = temp + var2; return (seed>>val13);}void LongNumInit( char *L, unsigned N ){ for ( int i=0; i<N;++i ) { L[i] = myRandom() % ten; // digito decimal }}void LongNumPrint( char *L, unsigned N, char *Name ){ printf("%s:", Name); for ( int i=N; i>0; i-- ) { printf("%d", L[i-1]); } printf("\n");}void LongNumSet( char *L, unsigned N, char digit ){ for (int i = 0; i < N; ++i){ L[i] = digit; }}void LongNumCopy( char *Vin, char *Vout, unsigned N ){ for ( int i=0; i< N; ++i ) { Vout[i] = Vin[i]; }}char LongNumAddition( char *__restrict Vin1, char * __restrict Vin2, char * __restrict Vout, unsigned N ){ char CARRY = 0,R,aux; Vin1 = (char*)__builtin_assume_aligned (Vin1, 1); Vin2 = (char*)__builtin_assume_aligned (Vin2, 1); for ( int i=0; i< N; ++i ) { char R = Vin1[i] + Vin2[i] + CARRY; aux = R <= 9; Vout[i] = (aux) ? R:R-ten; CARRY = (aux) ? 0:1; } return CARRY;}char LongNumAddDigit( char *V, char digit, unsigned N ){ int i=0; char R = V[0] + digit; if ( R < ten){ V[0] = R; return 0; } V[0] = R-ten; // add carry, maybe iteratively for all digits char CARRY = 1; i = 1; while ( CARRY && i < N ) { if ( V[i] < 9 ) { V[i]++; CARRY = 0; } else { V[i] = 0; i++; // CARRY remains set to 1 } } return CARRY;}char LongNumHorizAdd( char *Vin, char *Vout, unsigned N ){ char CARRY = 0; LongNumSet ( Vout, N, 0 ); for ( int i=0; i< N; ++i ) { LongNumAddDigit ( Vout, Vin[i], N ); } return 0; // CARRY can never be set}char LongNumConstMult( char *V, unsigned N, char digit ){ char CARRY = 0; char ja = 0; for ( int i=0; i< N; ++i ) { char aux = V[i] * digit; char R = aux + CARRY; CARRY = ((u_int32_t)R * (u_int32_t)0xCCCD) >> 19; ja = (CARRY << 3) + 2*CARRY; R -= ja; V[i] = R; } return CARRY; // may be from 0 to 9}void LongNumMultiply( char *Vin1, char *Vin2, char *VoutH, char *VoutL, unsigned N ){ // Create Temporal Long Integer with double size unsigned char *TEMP = (unsigned char*) calloc(2*N,sizeof(unsigned char)); unsigned char *RES = (unsigned char*) calloc( 2*N,sizeof(unsigned char) ); LongNumSet ( RES, 2*N, 0 ); // Set RES to 0 for ( int i=0; i<N; ++i ) { LongNumSet ( TEMP, 2*N, 0 ); // Set TEMP to 0 LongNumCopy ( Vin1, TEMP+i, N ); // Copy Vin1 -> TEMP, with offset i LongNumConstMult( TEMP, 2*N, Vin2[i] ); // TEMP * Vin2[i] -> TEMP LongNumAddition ( TEMP, RES, RES, 2*N ); // TEMP + RES -> RES } // Result goes to VoutH-VoutL LongNumCopy ( RES, VoutL, N ); // Copy RES -> VoutL LongNumCopy ( RES+N, VoutH, N ); // Copy RES+N -> VoutH}int main (int argc, char **argv){ int i, sum1, sum2, sum3, N=10000, Rep=50; seed = 12345; // obtain parameters at run time if (argc>1) { N = atoi(argv[1]); } if (argc>2) { Rep = atoi(argv[2]); } printf("Challenge #3: Vector size is %d. Repeat %d times\n", N, Rep); // Create Long Nums unsigned char *V1= (unsigned char*) malloc( N*sizeof(unsigned char) ); unsigned char *V2= (unsigned char*) malloc( N*sizeof(unsigned char) ); unsigned char *V3= (unsigned char*) malloc( N*sizeof(unsigned char) ); unsigned char *V4= (unsigned char*) malloc( N*sizeof(unsigned char) ); LongNumInit ( V1, N ); LongNumInit ( V2, N ); LongNumInit ( V3, N ); // Repeat for (i=0; i<Rep; i++) { LongNumAddition ( V1, V2, V4, N ); LongNumMultiply ( V3, V4, V2, V1, N ); LongNumHorizAdd ( V1, V2, N ); LongNumAddDigit ( V3, V2[0], N ); } // Print last 32 digits of Long Numbers LongNumPrint( V1, 32, "V1" ); LongNumPrint( V2, 32, "V2" ); LongNumPrint( V3, 32, "V3" ); LongNumPrint( V4, 32, "V4" ); free(V1); free(V2); free(V3); free(V4); return 0;}