/* Exactness test for the integer-dot kernels: dot_i8i8 and dot_i4i8 must return
 * EXACTLY the same value as a plain-C reference, whatever SIMD path was compiled
 * in (avx512-vnni / avx2 / neon / vsx / scalar). Integer arithmetic has no
 * rounding, so any mismatch is a kernel bug, not noise.
 *
 * Covers: odd sizes (scalar tail), sizes below one vector, the w=-128 edge
 * (sign-trick kernels must treat |−128| as 128 unsigned, not saturate to 127),
 * and random data at qrow_i8's contract (|x| <= 127, w full int8 range). */
#define main coli_glm_main_unused
#include "../glm.c"
#undef main

static uint32_t rng_state=0x12345678u;
static uint32_t xr(void){ rng_state^=rng_state<<13; rng_state^=rng_state>>17; rng_state^=rng_state<<5; return rng_state; }

static int32_t ref_i8i8(const int8_t *w, const int8_t *x, int I){
    int64_t s=0; for(int i=0;i<I;i++) s+=(int32_t)w[i]*x[i]; return (int32_t)s;
}
static int32_t ref_i4i8(const uint8_t *w4, const int8_t *x, int I){
    int64_t s=0;
    for(int i=0;i<I;i++){ uint8_t b=w4[i>>1]; int v=(i&1)?((int)(b>>4)-8):((int)(b&0xF)-8); s+=v*x[i]; }
    return (int32_t)s;
}

int main(void){
    static const int sizes[]={1,2,15,16,17,31,32,33,63,64,65,100,127,128,1408,4096,4097};
    static int8_t w[8192], x[8192]; static uint8_t w4[4096];
    for(unsigned t=0;t<sizeof(sizes)/sizeof(sizes[0]);t++){
        int I=sizes[t];
        for(int rep=0;rep<64;rep++){
            for(int i=0;i<I;i++) x[i]=(int8_t)((int)(xr()%255)-127);      /* [-127,127]: contratto di qrow_i8 */
            for(int i=0;i<I;i++) w[i]=(int8_t)((int)(xr()%256)-128);      /* [-128,127]: range pieno */
            if(rep==0) for(int i=0;i<I;i++) w[i]=-128;                    /* caso limite del trucco del segno */
            if(rep==1) for(int i=0;i<I;i++){ w[i]=127; x[i]=(int8_t)(i&1?-127:127); }
            for(int i=0;i<(I+1)/2;i++) w4[i]=(uint8_t)(xr()&0xFF);
            int32_t got=dot_i8i8(w,x,I), want=ref_i8i8(w,x,I);
            if(got!=want){ fprintf(stderr,"FAIL dot_i8i8 I=%d rep=%d: %d != %d\n",I,rep,got,want); return 1; }
            got=dot_i4i8(w4,x,I); want=ref_i4i8(w4,x,I);
            if(got!=want){ fprintf(stderr,"FAIL dot_i4i8 I=%d rep=%d: %d != %d\n",I,rep,got,want); return 1; }
        }
    }
    printf("idot kernel exactness (%s): ok\n", IDOT_KERNEL);
    return 0;
}