aboutsummaryrefslogtreecommitdiff
path: root/pocs/vdot/vdot.cpp
blob: 26bf50c9ac2e46891a98d8a20473b77b6efb0c80 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
#include <cstdio>
#include <vector>
#include <random>
#include <chrono>
#include <cstdlib>
#include <cmath>
#include <cassert>
#include <cstring>
#include <array>

#include <ggml.h>

constexpr int kVecSize = 1 << 18;

float drawFromGaussianPdf(std::mt19937& rndm) {
    constexpr double kScale = 1./(1. + std::mt19937::max());
    constexpr double kTwoPiTimesScale = 6.28318530717958647692*kScale;
    static float lastX;
    static bool haveX = false;
    if (haveX) { haveX = false; return lastX; }
    auto r = sqrt(-2*log(1 - kScale*rndm()));
    auto phi = kTwoPiTimesScale * rndm();
    lastX = r*sin(phi);
    haveX = true;
    return r*cos(phi);
}
void fillRandomGaussianFloats(std::vector<float>& values, std::mt19937& rndm, float mean = 0) {
    for (auto& v : values) v = mean + drawFromGaussianPdf(rndm);
}

// Copy-pasted from ggml.c
#define QK4_0 32
typedef struct {
    float   d;          // delta
    uint8_t qs[QK4_0 / 2];  // nibbles / quants
} block_q4_0;
static_assert(sizeof(block_q4_0) == sizeof(float) + QK4_0 / 2, "wrong q4_0 block size/padding");

#define QK4_1 32
typedef struct {
    float   d;          // delta
    float   m;          // min
    uint8_t qs[QK4_1 / 2];  // nibbles / quants
} block_q4_1;
static_assert(sizeof(block_q4_1) == sizeof(float) * 2 + QK4_1 / 2, "wrong q4_1 block size/padding");

// Copy-pasted from ggml.c
#define QK8_0 32
typedef struct {
    float   d;          // delta
    int8_t  qs[QK8_0];  // quants
} block_q8_0;
static_assert(sizeof(block_q8_0) == sizeof(float) + QK8_0, "wrong q8_0 block size/padding");

// "Scalar" dot product between the quantized vector x and float vector y
inline double dot(int n, const block_q4_0* x, const float* y) {
    const static float kValues[16] = {-8.f, -7.f, -6.f, -5.f, -4.f, -3.f, -2.f, -1.f, 0.f, 1.f, 2.f, 3.f, 4.f, 5.f, 6.f, 7.f};
    constexpr uint32_t kMask1 = 0x0f0f0f0f;
    uint32_t u1, u2;
    auto q1 = (const uint8_t*)&u1;
    auto q2 = (const uint8_t*)&u2;
    double sum = 0;
    for (int i=0; i<n; ++i) {
        float d = x->d;
        auto u = (const uint32_t*)x->qs;
        float s = 0;
        for (int k=0; k<4; ++k) {
            u1 = u[k] & kMask1;
            u2 = (u[k] >> 4) & kMask1;
            s += y[0]*kValues[q1[0]] + y[1]*kValues[q2[0]] +
                 y[2]*kValues[q1[1]] + y[3]*kValues[q2[1]] +
                 y[4]*kValues[q1[2]] + y[5]*kValues[q2[2]] +
                 y[6]*kValues[q1[3]] + y[7]*kValues[q2[3]];
            y += 8;
        }
        sum += s*d;
        ++x;
    }
    return sum;
}
// Alternative version of the above. Faster on my Mac (~45 us vs ~55 us per dot product),
// but about the same on X86_64 (Ryzen 7950X CPU).
inline double dot3(int n, const block_q4_0* x, const float* y) {
    const static std::pair<float,float> kValues[256] = {
        {-8.f, -8.f}, {-7.f, -8.f}, {-6.f, -8.f}, {-5.f, -8.f}, {-4.f, -8.f}, {-3.f, -8.f}, {-2.f, -8.f}, {-1.f, -8.f},
        { 0.f, -8.f}, { 1.f, -8.f}, { 2.f, -8.f}, { 3.f, -8.f}, { 4.f, -8.f}, { 5.f, -8.f}, { 6.f, -8.f}, { 7.f, -8.f},
        {-8.f, -7.f}, {-7.f, -7.f}, {-6.f, -7.f}, {-5.f, -7.f}, {-4.f, -7.f}, {-3.f, -7.f}, {-2.f, -7.f}, {-1.f, -7.f},
        { 0.f, -7.f}, { 1.f, -7.f}, { 2.f, -7.f}, { 3.f, -7.f}, { 4.f, -7.f}, { 5.f, -7.f}, { 6.f, -7.f}, { 7.f, -7.f},
        {-8.f, -6.f}, {-7.f, -6.f}, {-6.f, -6.f}, {-5.f, -6.f}, {-4.f, -6.f}, {-3.f, -6.f}, {-2.f, -6.f}, {-1.f, -6.f},
        { 0.f, -6.f}, { 1.f, -6.f}, { 2.f, -6.f}, { 3.f, -6.f}, { 4.f, -6.f}, { 5.f, -6.f}, { 6.f, -6.f}, { 7.f, -6.f},
        {-8.f, -5.f}, {-7.f, -5.f}, {-6.f, -5.f}, {-5.f, -5.f}, {-4.f, -5.f}, {-3.f, -5.f}, {-2.f, -5.f}, {-1.f, -5.f},
        { 0.f, -5.f}, { 1.f, -5.f}, { 2.f, -5.f}, { 3.f, -5.f}, { 4.f, -5.f}, { 5.f, -5.f}, { 6.f, -5.f}, { 7.f, -5.f},
        {-8.f, -4.f}, {-7.f, -4.f}, {-6.f, -4.f}, {-5.f, -4.f}, {-4.f, -4.f}, {-3.f, -4.f}, {-2.f, -4.f}, {-1.f, -4.f},
        { 0.f, -4.f}, { 1.f, -4.f}, { 2.f, -4.f}, { 3.f, -4.f}, { 4.f, -4.f}, { 5.f, -4.f}, { 6.f, -4.f}, { 7.f, -4.f},
        {-8.f, -3.f}, {-7.f, -3.f}, {-6.f, -3.f}, {-5.f, -3.f}, {-4.f, -3.f}, {-3.f, -3.f}, {-2.f, -3.f}, {-1.f, -3.f},
        { 0.f, -3.f}, { 1.f, -3.f}, { 2.f, -3.f}, { 3.f, -3.f}, { 4.f, -3.f}, { 5.f, -3.f}, { 6.f, -3.f}, { 7.f, -3.f},
        {-8.f, -2.f}, {-7.f, -2.f}, {-6.f, -2.f}, {-5.f, -2.f}, {-4.f, -2.f}, {-3.f, -2.f}, {-2.f, -2.f}, {-1.f, -2.f},
        { 0.f, -2.f}, { 1.f, -2.f}, { 2.f, -2.f}, { 3.f, -2.f}, { 4.f, -2.f}, { 5.f, -2.f}, { 6.f, -2.f}, { 7.f, -2.f},
        {-8.f, -1.f}, {-7.f, -1.f}, {-6.f, -1.f}, {-5.f, -1.f}, {-4.f, -1.f}, {-3.f, -1.f}, {-2.f, -1.f}, {-1.f, -1.f},
        { 0.f, -1.f}, { 1.f, -1.f}, { 2.f, -1.f}, { 3.f, -1.f}, { 4.f, -1.f}, { 5.f, -1.f}, { 6.f, -1.f}, { 7.f, -1.f},
        {-8.f,  0.f}, {-7.f,  0.f}, {-6.f,  0.f}, {-5.f,  0.f}, {-4.f,  0.f}, {-3.f,  0.f}, {-2.f,  0.f}, {-1.f,  0.f},
        { 0.f,  0.f}, { 1.f,  0.f}, { 2.f,  0.f}, { 3.f,  0.f}, { 4.f,  0.f}, { 5.f,  0.f}, { 6.f,  0.f}, { 7.f,  0.f},
        {-8.f,  1.f}, {-7.f,  1.f}, {-6.f,  1.f}, {-5.f,  1.f}, {-4.f,  1.f}, {-3.f,  1.f}, {-2.f,  1.f}, {-1.f,  1.f},
        { 0.f,  1.f}, { 1.f,  1.f}, { 2.f,  1.f}, { 3.f,  1.f}, { 4.f,  1.f}, { 5.f,  1.f}, { 6.f,  1.f}, { 7.f,  1.f},
        {-8.f,  2.f}, {-7.f,  2.f}, {-6.f,  2.f}, {-5.f,  2.f}, {-4.f,  2.f}, {-3.f,  2.f}, {-2.f,  2.f}, {-1.f,  2.f},
        { 0.f,  2.f}, { 1.f,  2.f}, { 2.f,  2.f}, { 3.f,  2.f}, { 4.f,  2.f}, { 5.f,  2.f}, { 6.f,  2.f}, { 7.f,  2.f},
        {-8.f,  3.f}, {-7.f,  3.f}, {-6.f,  3.f}, {-5.f,  3.f}, {-4.f,  3.f}, {-3.f,  3.f}, {-2.f,  3.f}, {-1.f,  3.f},
        { 0.f,  3.f}, { 1.f,  3.f}, { 2.f,  3.f}, { 3.f,  3.f}, { 4.f,  3.f}, { 5.f,  3.f}, { 6.f,  3.f}, { 7.f,  3.f},
        {-8.f,  4.f}, {-7.f,  4.f}, {-6.f,  4.f}, {-5.f,  4.f}, {-4.f,  4.f}, {-3.f,  4.f}, {-2.f,  4.f}, {-1.f,  4.f},
        { 0.f,  4.f}, { 1.f,  4.f}, { 2.f,  4.f}, { 3.f,  4.f}, { 4.f,  4.f}, { 5.f,  4.f}, { 6.f,  4.f}, { 7.f,  4.f},
        {-8.f,  5.f}, {-7.f,  5.f}, {-6.f,  5.f}, {-5.f,  5.f}, {-4.f,  5.f}, {-3.f,  5.f}, {-2.f,  5.f}, {-1.f,  5.f},
        { 0.f,  5.f}, { 1.f,  5.f}, { 2.f,  5.f}, { 3.f,  5.f}, { 4.f,  5.f}, { 5.f,  5.f}, { 6.f,  5.f}, { 7.f,  5.f},
        {-8.f,  6.f}, {-7.f,  6.f}, {-6.f,  6.f}, {-5.f,  6.f}, {-4.f,  6.f}, {-3.f,  6.f}, {-2.f,  6.f}, {-1.f,  6.f},
        { 0.f,  6.f}, { 1.f,  6.f}, { 2.f,  6.f}, { 3.f,  6.f}, { 4.f,  6.f}, { 5.f,  6.f}, { 6.f,  6.f}, { 7.f,  6.f},
        {-8.f,  7.f}, {-7.f,  7.f}, {-6.f,  7.f}, {-5.f,  7.f}, {-4.f,  7.f}, {-3.f,  7.f}, {-2.f,  7.f}, {-1.f,  7.f},
        { 0.f,  7.f}, { 1.f,  7.f}, { 2.f,  7.f}, { 3.f,  7.f}, { 4.f,  7.f}, { 5.f,  7.f}, { 6.f,  7.f}, { 7.f,  7.f}
    };
    double sum = 0;
    for (int i=0; i<n; ++i) {
        float d = x->d;
        auto q = x->qs;
        float s = 0;
        for (int k=0; k<4; ++k) {
            s += y[0]*kValues[q[0]].first + y[1]*kValues[q[0]].second +
                 y[2]*kValues[q[1]].first + y[3]*kValues[q[1]].second +
                 y[4]*kValues[q[2]].first + y[5]*kValues[q[2]].second +
                 y[6]*kValues[q[3]].first + y[7]*kValues[q[3]].second;
            y += 8; q += 4;
        }
        sum += s*d;
        ++x;
    }
    return sum;
}

inline double dot41(int n, const block_q4_1* x, const float* y) {
    const static float kValues[16] = {0.f, 1.f, 2.f, 3.f, 4.f, 5.f, 6.f, 7.f, 8.f, 9.f, 10.f, 11.f, 12.f, 13.f, 14.f, 15.f};
    constexpr uint32_t kMask1 = 0x0f0f0f0f;
    uint32_t u1, u2;
    auto q1 = (const uint8_t*)&u1;
    auto q2 = (const uint8_t*)&u2;
    double sum = 0;
    for (int i=0; i<n; ++i) {
        auto u = (const uint32_t*)x->qs;
        float s = 0, s1 = 0;
        for (int k=0; k<4; ++k) {
            u1 = u[k] & kMask1;
            u2 = (u[k] >> 4) & kMask1;
            s += y[0]*kValues[q1[0]] + y[1]*kValues[q2[0]] +
                 y[2]*kValues[q1[1]] + y[3]*kValues[q2[1]] +
                 y[4]*kValues[q1[2]] + y[5]*kValues[q2[2]] +
                 y[6]*kValues[q1[3]] + y[7]*kValues[q2[3]];
            s1 += y[0] + y[1] + y[2] + y[3] + y[4] + y[5] + y[6] + y[7];
            y += 8;
        }
        sum += s*x->d + s1*x->m;
        ++x;
    }
    return sum;
}

// Copy-pasted from ggml.c
static void quantize_row_q8_0_reference(const float *x, block_q8_0 *y, int k) {
    assert(k % QK8_0 == 0);
    const int nb = k / QK8_0;

    for (int i = 0; i < nb; i++) {
        float amax = 0.0f; // absolute max

        for (int l = 0; l < QK8_0; l++) {
            const float v = x[i*QK8_0 + l];
            amax = std::max(amax, fabsf(v));
        }

        const float d = amax / ((1 << 7) - 1);
        const float id = d ? 1.0f/d : 0.0f;

        y[i].d = d;

        for (int l = 0; l < QK8_0; ++l) {
            const float   v  = x[i*QK8_0 + l]*id;
            y[i].qs[l] = roundf(v);
        }
    }
}

// Copy-pasted from ggml.c
static void dot_q4_q8(const int n, float* s, const void* vx, const void* vy) {
    const int nb = n / QK8_0;
    const block_q4_0* x = (const block_q4_0*)vx;
    const block_q8_0* y = (const block_q8_0*)vy;
    float sumf = 0;
    for (int i = 0; i < nb; i++) {
        const float d0 = x[i].d;
        const float d1 = y[i].d;

        const uint8_t * p0 = x[i].qs;
        const  int8_t * p1 = y[i].qs;

        int sumi = 0;
        for (int j = 0; j < QK8_0/2; j++) {
            const uint8_t v0 = p0[j];

            const int i0 = (int8_t) (v0 & 0xf) - 8;
            const int i1 = (int8_t) (v0 >> 4)  - 8;

            const int i2 = p1[2*j + 0];
            const int i3 = p1[2*j + 1];

            sumi += i0*i2 + i1*i3;
        }
        sumf += d0*d1*sumi;
    }
    *s = sumf;
}

int main(int argc, char** argv) {

    int nloop = argc > 1 ? atoi(argv[1]) : 10;
    bool scalar = argc > 2 ? atoi(argv[2]) : false;
    bool useQ4_1 = argc > 3 ? atoi(argv[3]) : false;

    if (scalar && useQ4_1) {
        printf("It is not possible to use Q4_1 quantization and scalar implementations\n");
        return 1;
    }

    std::mt19937 rndm(1234);

    std::vector<float> x1(kVecSize), y1(kVecSize);
    int n4 = useQ4_1 ? kVecSize / QK4_1 : kVecSize / QK4_0; n4 = 64*((n4 + 63)/64);
    int n8 = kVecSize / QK8_0; n8 = 64*((n8 + 63)/64);

    auto funcs = useQ4_1 ? ggml_internal_get_quantize_fn(GGML_TYPE_Q4_1) : ggml_internal_get_quantize_fn(GGML_TYPE_Q4_0);

    std::vector<block_q4_0> q40;
    std::vector<block_q4_1> q41;
    if (useQ4_1) q41.resize(n4);
    else q40.resize(n4);
    std::vector<block_q8_0> q8(n8);
    std::vector<int64_t> H(16, 0);
    double sumt = 0, sumt2 = 0, maxt = 0;
    double sumqt = 0, sumqt2 = 0, maxqt = 0;
    double sum = 0, sumq = 0, exactSum = 0;
    for (int iloop=0; iloop<nloop; ++iloop) {

        // Fill vector x with random numbers
        fillRandomGaussianFloats(x1, rndm);

        // Fill vector y with random numbers
        fillRandomGaussianFloats(y1, rndm);

        // Compute the exact dot product
        for (int k=0; k<kVecSize; ++k) exactSum += x1[k]*y1[k];

        // quantize x.
        // Note, we do not include this in the timing as in practical application
        // we already have the quantized model weights.
        if (useQ4_1) {
            funcs.quantize_row_q(x1.data(), q41.data(), kVecSize);
        } else {
            funcs.quantize_row_q(x1.data(), q40.data(), kVecSize);
        }

        // Now measure time the dot product needs using the "scalar" version above
        auto t1 = std::chrono::high_resolution_clock::now();
        if (useQ4_1) sum += dot41(kVecSize / QK4_1, q41.data(), y1.data());
        else sum += dot(kVecSize / QK4_0, q40.data(), y1.data());
        auto t2 = std::chrono::high_resolution_clock::now();
        auto t = 1e-3*std::chrono::duration_cast<std::chrono::nanoseconds>(t2-t1).count();
        sumt += t; sumt2 += t*t; maxt = std::max(maxt, t);

        // And now measure the time needed to quantize y and perform the dot product with the quantized y
        t1 = std::chrono::high_resolution_clock::now();
        float result;
        if (scalar) {
            quantize_row_q8_0_reference(y1.data(), q8.data(), kVecSize);
            dot_q4_q8(kVecSize, &result, q40.data(), q8.data());
        }
        else {
            funcs.quantize_row_q_dot(y1.data(), q8.data(), kVecSize);
            if (useQ4_1) funcs.vec_dot_q(kVecSize, &result, q41.data(), q8.data());
            else funcs.vec_dot_q(kVecSize, &result, q40.data(), q8.data());
        }
        sumq += result;
        t2 = std::chrono::high_resolution_clock::now();
        t = 1e-3*std::chrono::duration_cast<std::chrono::nanoseconds>(t2-t1).count();
        sumqt += t; sumqt2 += t*t; maxqt = std::max(maxqt, t);

    }

    // Report the time (and the average of the dot products so the compiler does not come up with the idea
    // of optimizing away the function calls after figuring that the result is not used).
    sum /= nloop; sumq /= nloop;
    exactSum /= nloop;
    printf("Exact result: <dot> = %g\n",exactSum);
    printf("<dot> = %g, %g\n",sum,sumq);
    sumt /= nloop; sumt2 /= nloop; sumt2 -= sumt*sumt;
    if (sumt2 > 0) sumt2 = sqrt(sumt2);
    printf("time = %g +/- %g us. maxt = %g us\n",sumt,sumt2,maxt);
    sumqt /= nloop; sumqt2 /= nloop; sumqt2 -= sumqt*sumqt;
    if (sumqt2 > 0) sumqt2 = sqrt(sumqt2);
    printf("timeq = %g +/- %g us. maxt = %g us\n",sumqt,sumqt2,maxqt);
    return 0;
}