ggml : use full range for Q4_0 and Q4_2 quantization (#729)

* Use full range for q4_0 quantization

By keeping the sign of the highest magnitude, we can make sure the
highest value maps to -8, which is currently unused.
This is a bit of a freebie since it is fully backwards compatible with
the current format.

* Update quantize_row_q4_0 for AVX/AVX2

* Update quantize_row_q4_0 for WASM

Untested

* Update quantize_row_q4_0 for Arm NEON

* Update quantize_row_q4_0 for PowerPC

Untested

* Use full range for q4_2 quantization

examples/CMakeLists.txt

@@ -34,4 +34,5 @@ else()
     add_subdirectory(quantize-stats)
     add_subdirectory(perplexity)
     add_subdirectory(embedding)
+    add_subdirectory(save-load-state)
 endif()

examples/save-load-state/CMakeLists.txt

@@ -0,0 +1,4 @@
+set(TARGET save-load-state)
+add_executable(${TARGET} save-load-state.cpp)
+target_link_libraries(${TARGET} PRIVATE common llama ${CMAKE_THREAD_LIBS_INIT})
+target_compile_features(${TARGET} PRIVATE cxx_std_11)

examples/save-load-state/save-load-state.cpp

@@ -0,0 +1,128 @@
+#include <vector>
+#include <cstdio>
+#include <chrono>
+
+#include "common.h"
+#include "llama.h"
+#include "llama.cpp"
+
+using namespace std;
+
+int main(int argc, char ** argv) {
+    gpt_params params;
+    params.model = "models/llama-7B/ggml-model.bin";
+    params.seed = 42;
+    params.n_threads = 4;
+    params.repeat_last_n = 64;
+    params.prompt = "The quick brown fox";
+
+    if (gpt_params_parse(argc, argv, params) == false) {
+        return 1;
+    }
+
+    auto lparams = llama_context_default_params();
+
+    lparams.n_ctx      = params.n_ctx;
+    lparams.n_parts    = params.n_parts;
+    lparams.seed       = params.seed;
+    lparams.f16_kv     = params.memory_f16;
+    lparams.use_mmap   = params.use_mmap;
+    lparams.use_mlock  = params.use_mlock;
+
+    auto n_past = 0;
+    auto last_n_tokens_data = vector<llama_token>(params.repeat_last_n, 0);
+
+    // init
+    auto ctx = llama_init_from_file(params.model.c_str(), lparams);
+    auto tokens = vector<llama_token>(params.n_ctx);
+    auto n_prompt_tokens = llama_tokenize(ctx, params.prompt.c_str(), tokens.data(), tokens.size(), true);
+
+    if (n_prompt_tokens < 1) {
+        fprintf(stderr, "%s : failed to tokenize prompt\n", __func__);
+        return 1;
+    }
+
+    // evaluate prompt
+
+    llama_eval(ctx, tokens.data(), n_prompt_tokens, n_past, params.n_threads);
+
+    last_n_tokens_data.insert(last_n_tokens_data.end(), tokens.data(), tokens.data() + n_prompt_tokens);
+    n_past += n_prompt_tokens;
+
+    // Save state (rng, logits, embedding and kv_cache) to file
+    FILE *fp_write = fopen("dump_state.bin", "wb");
+    auto state_size = llama_get_state_size(ctx);
+    auto state_mem = new uint8_t[state_size];
+    llama_copy_state_data(ctx, state_mem); // could also copy directly to memory mapped file
+    fwrite(state_mem, 1, state_size, fp_write);
+    fclose(fp_write);
+
+    // save state (last tokens)
+    auto last_n_tokens_data_saved = vector<llama_token>(last_n_tokens_data);
+    auto n_past_saved = n_past;
+
+    // first run
+    printf("\n%s", params.prompt.c_str());
+    for (auto i = 0; i < params.n_predict; i++) {
+        auto next_token = llama_sample_top_p_top_k(
+            ctx,
+            &last_n_tokens_data.back() - params.repeat_last_n,
+            params.repeat_last_n,
+            40,
+            1.0,
+            1.0,
+            1.1);
+        auto next_token_str = llama_token_to_str(ctx, next_token);
+        last_n_tokens_data.push_back(next_token);
+        printf("%s", next_token_str);
+        if (llama_eval(ctx, &next_token, 1, n_past, params.n_threads)) {
+            fprintf(stderr, "\n%s : failed to evaluate\n", __func__);
+            return 1;
+        }
+        n_past += 1;
+    }
+    printf("\n\n");
+
+    // free old model
+    llama_free(ctx);
+
+    // load new model
+
+    auto ctx2 = llama_init_from_file(params.model.c_str(), lparams);
+
+    // Load state (rng, logits, embedding and kv_cache) from file
+    FILE *fp_read = fopen("dump_state.bin", "rb");
+    auto state_size2 = llama_get_state_size(ctx2);
+    if (state_size != state_size2) {
+        fprintf(stderr, "\n%s : failed to validate state size\n", __func__);
+    }
+    fread(state_mem, 1, state_size, fp_read);
+    llama_set_state_data(ctx2, state_mem);  // could also read directly from memory mapped file
+    fclose(fp_read);
+
+    // restore state (last tokens)
+    last_n_tokens_data = last_n_tokens_data_saved;
+    n_past = n_past_saved;
+
+    // second run
+    for (auto i = 0; i < params.n_predict; i++) {
+        auto next_token = llama_sample_top_p_top_k(
+            ctx2,
+            &last_n_tokens_data.back() - params.repeat_last_n,
+            params.repeat_last_n,
+            40,
+            1.0,
+            1.0,
+            1.1);
+        auto next_token_str = llama_token_to_str(ctx2, next_token);
+        last_n_tokens_data.push_back(next_token);
+        printf("%s", next_token_str);
+        if (llama_eval(ctx2, &next_token, 1, n_past, params.n_threads)) {
+            fprintf(stderr, "\n%s : failed to evaluate\n", __func__);
+            return 1;
+        }
+        n_past += 1;
+    }
+    printf("\n\n");
+    return 0;
+}

ggml.c

@@ -692,13 +692,17 @@ static void quantize_row_q4_0_reference(const float * restrict x, block_q4_0 * r
 
     for (int i = 0; i < nb; i++) {
         float amax = 0.0f; // absolute max
+        float max = 0.0f;
 
         for (int l = 0; l < QK4_0; l++) {
             const float v = x[i*QK4_0 + l];
-            amax = MAX(amax, fabsf(v));
+            if (amax < fabsf(v)) {
+                amax = fabsf(v);
+                max = v;
+            }
         }
 
-        const float d = amax / ((1 << 3) - 1);
+        const float d = max / -8;
         const float id = d ? 1.0f/d : 0.0f;
 
         y[i].d = d;
@@ -707,8 +711,8 @@ static void quantize_row_q4_0_reference(const float * restrict x, block_q4_0 * r
             const float v0 = x[i*QK4_0 + l + 0]*id;
             const float v1 = x[i*QK4_0 + l + 1]*id;
 
-            const uint8_t vi0 = (int8_t)roundf(v0) + 8;
-            const uint8_t vi1 = (int8_t)roundf(v1) + 8;
+            const uint8_t vi0 = MIN(15, (int8_t)roundf(v0) + 8);
+            const uint8_t vi1 = MIN(15, (int8_t)roundf(v1) + 8);
 
             assert(vi0 < 16);
             assert(vi1 < 16);
@@ -728,28 +732,42 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
 
 #if defined(__POWER9_VECTOR__)
     const vector float v85 = vec_splats(8.5f);
+    const vector signed int v15 = vec_splats(15);
     for (int i = 0; i < nb; i++) {
-        float amax = 0.0f; // absolute max
+        float max = 0.0f;
+        float min = 0.0f;
 
         vector float srcv [8];
-        vector float asrcv[8];
-        vector float amaxv[8];
+        vector float maxv[8];
+        vector float minv[8];
 
         for (int l = 0; l < 8; l++) srcv[l]  = *(vector float *)(x + i*32 + 4*l);
-        for (int l = 0; l < 8; l++) asrcv[l] = vec_abs(srcv[l]);
+        //for (int l = 0; l < 8; l++) asrcv[l] = vec_abs(srcv[l]);
 
-        for (int l = 0; l < 4; l++) amaxv[2*l] = vec_max(asrcv[2*l], asrcv[2*l+1]);
-        //for (int l = 0; l < 2; l++) amaxv[4*l] = vec_max(amaxv[4*l], amaxv[4*l+2]);
-        amaxv[0] = vec_max(amaxv[0], amaxv[2]);
-        amaxv[4] = vec_max(amaxv[4], amaxv[6]);
-        //for (int l = 0; l < 1; l++) amaxv[8*l] = vec_max(amaxv[8*l], amaxv[8*l+4]);
-        amaxv[0] = vec_max(amaxv[0], amaxv[4]);
+        for (int l = 0; l < 4; l++) maxv[2*l] = vec_max(asrcv[2*l], asrcv[2*l+1]);
+        //for (int l = 0; l < 2; l++) maxv[4*l] = vec_max(maxv[4*l], maxv[4*l+2]);
+        maxv[0] = vec_max(maxv[0], maxv[2]);
+        maxv[4] = vec_max(maxv[4], maxv[6]);
+        //for (int l = 0; l < 1; l++) maxv[8*l] = vec_max(maxv[8*l], maxv[8*l+4]);
+        maxv[0] = vec_max(maxv[0], maxv[4]);
 
-        amax = MAX(
-                MAX(vec_extract(amaxv[0], 0), vec_extract(amaxv[0], 1)),
-                MAX(vec_extract(amaxv[0], 2), vec_extract(amaxv[0], 3)));
+        for (int l = 0; l < 4; l++) minv[2*l] = vec_min(asrcv[2*l], asrcv[2*l+1]);
+        //for (int l = 0; l < 2; l++) minv[4*l] = vec_min(minv[4*l], minv[4*l+2]);
+        minv[0] = vec_min(minv[0], minv[2]);
+        minv[4] = vec_min(minv[4], minv[6]);
+        //for (int l = 0; l < 1; l++) minv[8*l] = vec_min(minv[8*l], minv[8*l+4]);
+        minv[0] = vec_min(minv[0], minv[4]);
 
-        const float d = amax / ((1 << 3) - 1);
+
+        max = MAX(
+                MAX(vec_extract(maxv[0], 0), vec_extract(maxv[0], 1)),
+                MAX(vec_extract(maxv[0], 2), vec_extract(maxv[0], 3)));
+        min = MIN(
+                MIN(vec_extract(minv[0], 0), vec_extract(minv[0], 1)),
+                MIN(vec_extract(minv[0], 2), vec_extract(minv[0], 3)));
+
+        const float magnitude = max >= fabsf(min) ? max : min;
+        const float d = magnitude / -8;
         const float id = d ? 1.0/d : 0.0;
 
         y[i].d = d;
@@ -759,27 +777,33 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
         for (int l = 0; l < 8; l++) {
             const vector float vf  = vec_madd(srcv[l], vid, v85);
             const vector signed int vi = vec_signed(vf);
+            const vector signed int vc = vec_min(vi, v15);
 
-            pb[2*l + 0] = vec_extract(vi, 0) | (vec_extract(vi, 1) << 4);
-            pb[2*l + 1] = vec_extract(vi, 2) | (vec_extract(vi, 3) << 4);
+            pb[2*l + 0] = vec_extract(vc, 0) | (vec_extract(vc, 1) << 4);
+            pb[2*l + 1] = vec_extract(vc, 2) | (vec_extract(vc, 3) << 4);
         }
     }
 #elif __ARM_NEON
     for (int i = 0; i < nb; i++) {
         float32x4_t srcv [8];
-        float32x4_t asrcv[8];
-        float32x4_t amaxv[8];
+        float32x4_t maxv[8];
+        float32x4_t minv[8];
 
         for (int l = 0; l < 8; l++) srcv[l]  = vld1q_f32(x + i*32 + 4*l);
-        for (int l = 0; l < 8; l++) asrcv[l] = vabsq_f32(srcv[l]);
 
-        for (int l = 0; l < 4; l++) amaxv[2*l] = vmaxq_f32(asrcv[2*l], asrcv[2*l+1]);
-        for (int l = 0; l < 2; l++) amaxv[4*l] = vmaxq_f32(amaxv[4*l], amaxv[4*l+2]);
-        for (int l = 0; l < 1; l++) amaxv[8*l] = vmaxq_f32(amaxv[8*l], amaxv[8*l+4]);
+        for (int l = 0; l < 4; l++) maxv[2*l] = vmaxq_f32(srcv[2*l], srcv[2*l+1]);
+        for (int l = 0; l < 2; l++) maxv[4*l] = vmaxq_f32(maxv[4*l], maxv[4*l+2]);
+        for (int l = 0; l < 1; l++) maxv[8*l] = vmaxq_f32(maxv[8*l], maxv[8*l+4]);
 
-        const float amax = vmaxvq_f32(amaxv[0]);
+        for (int l = 0; l < 4; l++) minv[2*l] = vminq_f32(srcv[2*l], srcv[2*l+1]);
+        for (int l = 0; l < 2; l++) minv[4*l] = vminq_f32(minv[4*l], minv[4*l+2]);
+        for (int l = 0; l < 1; l++) minv[8*l] = vminq_f32(minv[8*l], minv[8*l+4]);
 
-        const float d = amax / ((1 << 3) - 1);
+        const float max = vmaxvq_f32(maxv[0]);
+        const float min = vminvq_f32(minv[0]);
+
+        const float magnitude = max >= fabsf(min) ? max : min;
+        const float d = magnitude / -8;
         const float id = d ? 1.0f/d : 0.0f;
 
         y[i].d = d;
@@ -788,9 +812,10 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
             const float32x4_t v  = vmulq_n_f32(srcv[l], id);
             const float32x4_t vf = vaddq_f32(v, vdupq_n_f32(8.5f));
             const int32x4_t   vi = vcvtq_s32_f32(vf);
+            const int32x4_t   vc = vminq_s32(vi, vdupq_n_s32(15));
 
-            y[i].qs[2*l + 0] = vgetq_lane_s32(vi, 0) | (vgetq_lane_s32(vi, 1) << 4);
-            y[i].qs[2*l + 1] = vgetq_lane_s32(vi, 2) | (vgetq_lane_s32(vi, 3) << 4);
+            y[i].qs[2*l + 0] = vgetq_lane_s32(vc, 0) | (vgetq_lane_s32(vc, 1) << 4);
+            y[i].qs[2*l + 1] = vgetq_lane_s32(vc, 2) | (vgetq_lane_s32(vc, 3) << 4);
         }
     }
 #elif defined(__AVX2__)
@@ -802,22 +827,31 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
         __m256 v3 = _mm256_loadu_ps( x + 24 );
         x += 32;
 
-        // Compute max(abs(e)) for the block
-        const __m256 signBit = _mm256_set1_ps( -0.0f );
-        __m256 maxAbs = _mm256_andnot_ps( signBit, v0 );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v1 ) );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v2 ) );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v3 ) );
+        // Compute max for the block
+        __m256 max  = _mm256_max_ps( v0, v1 );
+        __m256 maxTmp = _mm256_max_ps( v2, v3 );
+        max = _mm256_max_ps( max, maxTmp );
 
-        __m128 max4 = _mm_max_ps( _mm256_extractf128_ps( maxAbs, 1 ), _mm256_castps256_ps128( maxAbs ) );
+        __m128 max4 = _mm_max_ps( _mm256_extractf128_ps( max, 1 ), _mm256_castps256_ps128( max ) );
         max4 = _mm_max_ps( max4, _mm_movehl_ps( max4, max4 ) );
         max4 = _mm_max_ss( max4, _mm_movehdup_ps( max4 ) );
         const float maxScalar = _mm_cvtss_f32( max4 );
 
+        // Compute min for the block
+        __m256 min  = _mm256_min_ps( v0, v1 );
+        __m256 minTmp = _mm256_min_ps( v2, v3 );
+        min = _mm256_min_ps( min, minTmp );
+
+        __m128 min4 = _mm_min_ps( _mm256_extractf128_ps( min, 1 ), _mm256_castps256_ps128( min ) );
+        min4 = _mm_min_ps( min4, _mm_movehl_ps( min4, min4 ) );
+        min4 = _mm_min_ss( min4, _mm_movehdup_ps( min4 ) );
+        const float minScalar = _mm_cvtss_f32( min4 );
+
         // Quantize these floats
-        const float d = maxScalar / 7.0f;
+        const float magnitude = maxScalar >= fabsf(minScalar) ? maxScalar : minScalar;
+        const float d = magnitude / -8.0f;
         y[i].d = d;
-        const float id = ( maxScalar != 0.0f ) ? 7.0f / maxScalar : 0.0f;
+        const float id = ( magnitude != 0.0f ) ? -8.0f / magnitude : 0.0f;
         const __m256 mul = _mm256_set1_ps( id );
 
         // Apply the multiplier
@@ -850,9 +884,11 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
         const __m256i perm = _mm256_setr_epi32( 0, 4, 1, 5, 2, 6, 3, 7 );
         i0 = _mm256_permutevar8x32_epi32( i0, perm );
 
-        // Apply offset to translate the range from [ -7 .. +7 ] into [ +1 .. +15 ]
+        // Apply offset and clamp to translate the range from [ -8 .. +8 ] into [ +0 .. +15 ]
         const __m256i off = _mm256_set1_epi8( 8 );
         i0 = _mm256_add_epi8( i0, off );
+        const __m256i maxNibble = _mm256_set1_epi8( 15 );
+        i0 = _mm256_min_epi8( i0, maxNibble );
 
         // Compress the vector into 4 bit/value, and store
         __m128i res = packNibbles( i0 );
@@ -867,22 +903,31 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
         __m256 v3 = _mm256_loadu_ps( x + 24 );
         x += 32;
 
-        // Compute max(abs(e)) for the block
-        const __m256 signBit = _mm256_set1_ps( -0.0f );
-        __m256 maxAbs = _mm256_andnot_ps( signBit, v0 );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v1 ) );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v2 ) );
-        maxAbs = _mm256_max_ps( maxAbs, _mm256_andnot_ps( signBit, v3 ) );
+        // Compute max for the block
+        __m256 max  = _mm256_max_ps( v0, v1 );
+        __m256 maxTmp = _mm256_max_ps( v2, v3 );
+        max = _mm256_max_ps( max, maxTmp );
 
-        __m128 max4 = _mm_max_ps( _mm256_extractf128_ps( maxAbs, 1 ), _mm256_castps256_ps128( maxAbs ) );
+        __m128 max4 = _mm_max_ps( _mm256_extractf128_ps( max, 1 ), _mm256_castps256_ps128( max ) );
         max4 = _mm_max_ps( max4, _mm_movehl_ps( max4, max4 ) );
         max4 = _mm_max_ss( max4, _mm_movehdup_ps( max4 ) );
         const float maxScalar = _mm_cvtss_f32( max4 );
 
+        // Compute min for the block
+        __m256 min  = _mm256_min_ps( v0, v1 );
+        __m256 minTmp = _mm256_min_ps( v2, v3 );
+        min = _mm256_min_ps( min, minTmp );
+
+        __m128 min4 = _mm_min_ps( _mm256_extractf128_ps( min, 1 ), _mm256_castps256_ps128( min ) );
+        min4 = _mm_min_ps( min4, _mm_movehl_ps( min4, min4 ) );
+        min4 = _mm_min_ss( min4, _mm_movehdup_ps( min4 ) );
+        const float minScalar = _mm_cvtss_f32( min4 );
+
         // Quantize these floats
-        const float d = maxScalar / 7.0f;
+        const float magnitude = maxScalar >= fabsf(minScalar) ? maxScalar : minScalar;
+        const float d = magnitude / -8.0f;
         y[i].d = d;
-        const float id = ( maxScalar != 0.0f ) ? 7.0f / maxScalar : 0.0f;
+        const float id = ( magnitude != 0.0f ) ? -8.0f / magnitude : 0.0f;
         const __m256 mul = _mm256_set1_ps( id );
 
         // Apply the multiplier
@@ -923,10 +968,13 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
         ni0 = _mm_packs_epi16( ni0, ni2 );
         ni4 = _mm_packs_epi16( ni4, ni6 );
 
-        // Apply offset to translate the range from [ -7 .. +7 ] into [ +1 .. +15 ]
-        const __m128i off = _mm_set1_epi8( 8);
+        // Apply offset and clamp to translate the range from [ -8 .. +8 ] into [ +0 .. +15 ]
+        const __m128i off = _mm_set1_epi8( 8 );
         ni0 = _mm_add_epi8( ni0, off );
         ni4 = _mm_add_epi8( ni4, off );
+        const __m128i maxNibble = _mm_set1_epi8( 15 );
+        ni0 = _mm_min_epi8( ni0, maxNibble );
+        ni4 = _mm_min_epi8( ni4, maxNibble );
 
         // Compress the vector into 4 bit/value, and store
         __m128i res = packNibbles( ni0, ni4 );
@@ -934,24 +982,32 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
     }
 #elif defined(__wasm_simd128__)
     for (int i = 0; i < nb; i++) {
-        float amax = 0.0f; // absolute max
+        float max = 0.0f;
+        float min = 0.0f;
 
         v128_t srcv [8];
-        v128_t asrcv[8];
-        v128_t amaxv[8];
+        v128_t maxv[8];
+        v128_t minv[8];
 
         for (int l = 0; l < 8; l++) srcv[l]  = wasm_v128_load(x + i*32 + 4*l);
-        for (int l = 0; l < 8; l++) asrcv[l] = wasm_f32x4_abs(srcv[l]);
 
-        for (int l = 0; l < 4; l++) amaxv[2*l] = wasm_f32x4_max(asrcv[2*l], asrcv[2*l+1]);
-        for (int l = 0; l < 2; l++) amaxv[4*l] = wasm_f32x4_max(amaxv[4*l], amaxv[4*l+2]);
-        for (int l = 0; l < 1; l++) amaxv[8*l] = wasm_f32x4_max(amaxv[8*l], amaxv[8*l+4]);
+        for (int l = 0; l < 4; l++) maxv[2*l] = wasm_f32x4_max(srcv[2*l], srcv[2*l+1]);
+        for (int l = 0; l < 2; l++) maxv[4*l] = wasm_f32x4_max(maxv[4*l], maxv[4*l+2]);
+        for (int l = 0; l < 1; l++) maxv[8*l] = wasm_f32x4_max(maxv[8*l], maxv[8*l+4]);
 
-        amax = MAX(
-                MAX(wasm_f32x4_extract_lane(amaxv[0], 0), wasm_f32x4_extract_lane(amaxv[0], 1)),
-                MAX(wasm_f32x4_extract_lane(amaxv[0], 2), wasm_f32x4_extract_lane(amaxv[0], 3)));
+        for (int l = 0; l < 4; l++) minv[2*l] = wasm_f32x4_min(srcv[2*l], srcv[2*l+1]);
+        for (int l = 0; l < 2; l++) minv[4*l] = wasm_f32x4_min(minv[4*l], minv[4*l+2]);
+        for (int l = 0; l < 1; l++) minv[8*l] = wasm_f32x4_min(minv[8*l], minv[8*l+4]);
 
-        const float d = amax / ((1 << 3) - 1);
+        max = MAX(
+                MAX(wasm_f32x4_extract_lane(maxv[0], 0), wasm_f32x4_extract_lane(maxv[0], 1)),
+                MAX(wasm_f32x4_extract_lane(maxv[0], 2), wasm_f32x4_extract_lane(maxv[0], 3)));
+        min = MIN(
+                MIN(wasm_f32x4_extract_lane(minv[0], 0), wasm_f32x4_extract_lane(minv[0], 1)),
+                MIN(wasm_f32x4_extract_lane(minv[0], 2), wasm_f32x4_extract_lane(minv[0], 3)));
+
+        const float magnitude = max >= fabsf(min) ? max : min;
+        const float d = magnitude / -8;
         const float id = d ? 1.0/d : 0.0;
 
         y[i].d = d;
@@ -960,9 +1016,10 @@ static void quantize_row_q4_0(const float * restrict x, void * restrict vy, int
             const v128_t v  = wasm_f32x4_mul(srcv[l], wasm_f32x4_splat(id));
             const v128_t vf = wasm_f32x4_add(v, wasm_f32x4_splat(8.5f));
             const v128_t vi = wasm_i32x4_trunc_sat_f32x4(vf);
+            const v128_t vc = wasm_i32x4_min_u(vi, wasm_i32x4_splat(15));
 
-            y[i].qs[2*l + 0] = wasm_i32x4_extract_lane(vi, 0) | (wasm_i32x4_extract_lane(vi, 1) << 4);
-            y[i].qs[2*l + 1] = wasm_i32x4_extract_lane(vi, 2) | (wasm_i32x4_extract_lane(vi, 3) << 4);
+            y[i].qs[2*l + 0] = wasm_i32x4_extract_lane(vc, 0) | (wasm_i32x4_extract_lane(vc, 1) << 4);
+            y[i].qs[2*l + 1] = wasm_i32x4_extract_lane(vc, 2) | (wasm_i32x4_extract_lane(vc, 3) << 4);
         }
     }
 #else
@@ -1143,13 +1200,17 @@ static void quantize_row_q4_2_reference(const float * restrict x, block_q4_2 * r
 
     for (int i = 0; i < nb; i++) {
         float amax = 0.0f; // absolute max
+        float max = 0.0f;
 
         for (int l = 0; l < QK4_2; l++) {
             const float v = x[i*QK4_2 + l];
-            amax = MAX(amax, fabsf(v));
+            if (amax < fabsf(v)) {
+                amax = fabsf(v);
+                max = v;
+            }
         }
 
-        const float d = amax / ((1 << 3) - 1);
+        const float d = max / -8;
 
         const float id = d ? 1.0f/d : 0.0f;
 
@@ -1159,8 +1220,8 @@ static void quantize_row_q4_2_reference(const float * restrict x, block_q4_2 * r
             const float v0 = x[i*QK4_2 + l + 0]*id;
             const float v1 = x[i*QK4_2 + l + 1]*id;
 
-            const uint8_t vi0 = (uint8_t)(v0 + 8.5f);
-            const uint8_t vi1 = (uint8_t)(v1 + 8.5f);
+            const uint8_t vi0 = MIN(15, (uint8_t)(v0 + 8.5f));
+            const uint8_t vi1 = MIN(15, (uint8_t)(v1 + 8.5f));
 
             assert(vi0 < 16);
             assert(vi1 < 16);
@@ -1254,9 +1315,7 @@ static void quantize_row_q4_2(const float * restrict x, void * restrict vy, int
 
     block_q4_2 * restrict y = vy;
 
-    //quantize_row_q4_2_reference(x, y, k);
-    // This produces the exact same format, just better match to the input floats ("better" as measured by RMSE)
-    quantize_row_q4_2_rmse(x, y, k);
+    quantize_row_q4_2_reference(x, y, k);
 }
 
 static void quantize_row_q4_3_reference(const float * restrict x, block_q4_3 * restrict y, int k) {
@@ -1807,7 +1866,7 @@ static const quantize_fns_t quantize_fns[GGML_TYPE_COUNT] = {
     [GGML_TYPE_Q4_2] = {
         .dequantize_row_q         = dequantize_row_q4_2,
         .quantize_row_q           = quantize_row_q4_2,
-        .quantize_row_q_reference = (quantize_row_q_t) quantize_row_q4_2_rmse, //quantize_row_q4_2_reference,
+        .quantize_row_q_reference = (quantize_row_q_t) quantize_row_q4_2_reference,
         .quantize_row_q_dot       = quantize_row_q8_0,
         .vec_dot_q                = ggml_vec_dot_q4_2_q8_0,
     },
@@ -6779,15 +6838,20 @@ static void ggml_compute_forward_sum_f32(
     const size_t nb02 = src0->nb[2];
     const size_t nb03 = src0->nb[3];
 
+    ggml_float sum     = 0;
+    float      row_sum = 0;
+
     for (int64_t i03 = 0; i03 < ne03; i03++) {
         for (int64_t i02 = 0; i02 < ne02; i02++) {
             for (int64_t i01 = 0; i01 < ne01; i01++) {
                 ggml_vec_sum_f32(ne00,
-                        (float *) (dst->data),
+                        &row_sum,
                         (float *) ((char *) src0->data + i01*nb01 + i02*nb02 + i03*nb03));
+                sum += row_sum;
             }
         }
     }
+    ((float *) dst->data)[0] = sum;
 }
 
 static void ggml_compute_forward_sum(
@@ -12139,8 +12203,7 @@ size_t ggml_quantize_q4_2(const float * src, void * dst, int n, int k, int64_t *
     for (int j = 0; j < n; j += k) {
         block_q4_2 * restrict y = (block_q4_2 *)dst + j/QK4_2;
 
-        //quantize_row_q4_2_reference(src + j, y, k);
-        quantize_row_q4_2_rmse(src + j, y, k);
+        quantize_row_q4_2_reference(src + j, y, k);
 
         for (int i = 0; i < nb; i++) {
             for (int l = 0; l < QK4_2; l += 2) {

llama.cpp

@@ -54,7 +54,7 @@ static const std::map<e_model, size_t> & MEM_REQ_SCRATCH0()
         { MODEL_7B,    512ull * MB },
         { MODEL_13B,   512ull * MB },
         { MODEL_30B,   512ull * MB },
-        { MODEL_65B,   512ull * MB },
+        { MODEL_65B,  1024ull * MB },
     };
     return _MEM_REQ_SCRATCH0;
 }
@@ -65,7 +65,7 @@ static const std::map<e_model, size_t> & MEM_REQ_SCRATCH1()
         { MODEL_7B,    512ull * MB },
         { MODEL_13B,   512ull * MB },
         { MODEL_30B,   512ull * MB },
-        { MODEL_65B,   512ull * MB },
+        { MODEL_65B,  1024ull * MB },
     };
     return _MEM_REQ_SCRATCH1;
 }