hexagon: enable support for NORM op (ggml-org#23319)

Author: aparmp-quic

ggml/src/ggml-hexagon/ggml-hexagon.cpp

@@ -2870,6 +2870,7 @@ static htp_op_code op_remap_to_htp(const ggml_tensor * t) {
         case GGML_OP_SET_ROWS:        return HTP_OP_SET_ROWS;
         case GGML_OP_SUM_ROWS:        return HTP_OP_SUM_ROWS;
         case GGML_OP_ARGSORT:         return HTP_OP_ARGSORT;
+        case GGML_OP_NORM:            return HTP_OP_NORM;
         case GGML_OP_L2_NORM:         return HTP_OP_L2_NORM;
         case GGML_OP_RMS_NORM:        return HTP_OP_RMS_NORM;
         case GGML_OP_SCALE:           return HTP_OP_SCALE;
@@ -3338,10 +3339,8 @@ static bool ggml_backend_hexagon_device_supports_op(ggml_backend_dev_t dev, cons
             supp = ggml_hexagon_supported_add_id(sess, op);
             break;
 
+        case GGML_OP_NORM:
         case GGML_OP_L2_NORM:
-            supp = ggml_hexagon_supported_unary(sess, op);
-            break;
-
         case GGML_OP_RMS_NORM:
         case GGML_OP_SCALE:
             supp = ggml_hexagon_supported_unary(sess, op);

ggml/src/ggml-hexagon/htp/htp-ops.h

@@ -88,6 +88,7 @@ enum htp_op_code {
     HTP_OP_GATED_DELTA_NET,
     HTP_OP_TRI,
     HTP_OP_PAD,
+    HTP_OP_NORM,
 
     HTP_OP_INVALID
 };

ggml/src/ggml-hexagon/htp/main.c

@@ -534,6 +534,7 @@ static int execute_op(struct htp_ops_context * octx) {
         case HTP_OP_ADD_ID:
             return op_binary(octx);
 
+        case HTP_OP_NORM:
         case HTP_OP_RMS_NORM:
         case HTP_OP_SCALE:
         case HTP_OP_SQR:

ggml/src/ggml-hexagon/htp/unary-ops.c

@@ -158,6 +158,79 @@ static void hvx_fast_rms_norm_f32(const uint8_t * restrict src,
     }
 }
 
+static void hvx_fast_norm_f32(const uint8_t * restrict src,
+                                  uint8_t * restrict dst,
+                                  uint8_t * restrict pad,
+                                  const int num_elems,
+                                  float     epsilon) {
+    (void)pad;
+
+    const HVX_Vector * restrict v_src = (HVX_Vector *) src;
+    HVX_Vector * restrict v_dst       = (HVX_Vector *) dst;
+
+    const int nvec = num_elems / VLEN_FP32;    // number of full vectors
+    const int nloe = num_elems % VLEN_FP32;    // leftover elements
+
+    // Compute sum of squares and sum of values for full vectors
+    HVX_Vector sum_sq_v = Q6_V_vsplat_R(0x00000000);
+    HVX_Vector sum_x_v  = Q6_V_vsplat_R(0x00000000);
+    HVX_Vector epsilon_v = hvx_vec_splat_f32(epsilon);
+
+    #pragma unroll(4)
+    for (int i = 0; i < nvec; i++) {
+        HVX_Vector v1 = v_src[i];
+        HVX_Vector v2 = Q6_Vqf32_vmpy_VsfVsf(v1, v1);
+        sum_sq_v = Q6_Vqf32_vadd_Vqf32Vqf32(sum_sq_v, v2);
+        sum_x_v  = Q6_Vqf32_vadd_Vqf32Vqf32(sum_x_v,  Q6_Vqf32_vadd_VsfVsf(v1, Q6_V_vzero()));
+    }
+
+    // Handle tail elements using vectorized ops with masking
+    if (nloe > 0) {
+        HVX_VectorPred bmask = Q6_Q_vsetq_R(nloe * 4);
+        HVX_Vector v1 = Q6_V_vand_QV(bmask, v_src[nvec]);
+        HVX_Vector v2 = Q6_Vqf32_vmpy_VsfVsf(v1, v1);
+        sum_sq_v = Q6_Vqf32_vadd_Vqf32Vqf32(sum_sq_v, v2);
+        sum_x_v  = Q6_Vqf32_vadd_Vqf32Vqf32(sum_x_v,  Q6_Vqf32_vadd_VsfVsf(v1, Q6_V_vzero()));
+    }
+
+    // Reduce HVX sums
+    sum_sq_v = hvx_vec_reduce_sum_f32(Q6_Vsf_equals_Vqf32(sum_sq_v));
+    sum_x_v  = hvx_vec_reduce_sum_f32(Q6_Vsf_equals_Vqf32(sum_x_v));
+
+    HVX_Vector t_v            = hvx_vec_splat_f32((float) num_elems);
+    HVX_Vector denom_v        = hvx_vec_inverse_f32(t_v);
+    HVX_Vector mean_sq_v      = Q6_Vqf32_vmpy_VsfVsf(sum_sq_v, denom_v);
+    HVX_Vector mean_x_v       = Q6_Vqf32_vmpy_VsfVsf(sum_x_v,  denom_v);
+    HVX_Vector mean_x_sq_v    = Q6_Vqf32_vmpy_VsfVsf(Q6_Vsf_equals_Vqf32(mean_x_v), Q6_Vsf_equals_Vqf32(mean_x_v));
+    HVX_Vector var_v          = Q6_Vqf32_vsub_Vqf32Vqf32(mean_sq_v, mean_x_sq_v);
+    HVX_Vector var_epsilon_v  = Q6_Vqf32_vadd_Vqf32Vsf(var_v, epsilon_v);
+
+    // scale = rsqrt(variance + epsilon),  mean_x broadcast for subtraction
+    HVX_Vector scale_v  = hvx_vec_rsqrt_f32(Q6_Vsf_equals_Vqf32(var_epsilon_v));
+    HVX_Vector mean_x_b = hvx_vec_splat_f32(hvx_vec_get_f32(Q6_Vsf_equals_Vqf32(mean_x_v)));
+
+    #pragma unroll(4)
+    for (int i = 0; i < nvec; i++) {
+        HVX_Vector v1 = v_src[i];
+        HVX_Vector v2 = Q6_Vqf32_vsub_VsfVsf(v1, mean_x_b);
+        HVX_Vector v3 = Q6_Vqf32_vmpy_VsfVsf(Q6_Vsf_equals_Vqf32(v2), scale_v);
+        v_dst[i] = Q6_Vsf_equals_Vqf32(v3);
+    }
+
+    // Handle tail elements using vectorized ops with masking
+    if (nloe > 0) {
+
+        HVX_VectorPred bmask = Q6_Q_vsetq_R(nloe * 4);
+        HVX_Vector v1 = Q6_V_vand_QV(bmask, v_src[nvec]);
+        HVX_Vector v2 = Q6_Vqf32_vsub_VsfVsf(v1, mean_x_b);
+        HVX_Vector v3 = Q6_Vqf32_vmpy_VsfVsf(Q6_Vsf_equals_Vqf32(v2), scale_v);
+        HVX_Vector result = Q6_Vsf_equals_Vqf32(v3);
+
+        // Store with masking to avoid overwriting memory beyond the tensor
+        hvx_vec_store_a(&v_dst[nvec], nloe * 4, result);
+    }
+}
+
 static void scale_f32(const float * restrict src,
                       float * restrict dst,
                       uint8_t * restrict spad,
@@ -196,6 +269,24 @@ static void rms_norm_f32(const float * restrict src,
     }
 }
 
+static void norm_f32(const float * restrict src,
+                         float * restrict dst,
+                         uint8_t * restrict spad,
+                         const uint32_t num_rows,
+                         const uint32_t row_elems,
+                         const size_t   row_size,
+                         int32_t *      op_params) {
+    float epsilon = 0.f;
+    memcpy(&epsilon, op_params, sizeof(float));
+
+    for (uint32_t ir = 0; ir < num_rows; ir++) {
+        const uint8_t * restrict src_local = (const uint8_t *)src + (ir * row_size);
+        uint8_t * restrict dst_local       = (uint8_t *)dst + (ir * row_size);
+
+        hvx_fast_norm_f32((const uint8_t *) src_local, (uint8_t *) dst_local, spad, row_elems, epsilon);
+    }
+}
+
 static void sqr_f32(const float * restrict src,
                     float * restrict dst,
                     uint8_t * restrict spad,
@@ -556,6 +647,9 @@ static void unary_job_f32_per_thread(unsigned int nth, unsigned int ith, void *
 
         // Process block in VTCM
         switch (htp_op) {
+            case HTP_OP_NORM:
+                norm_f32(src0_spad, dst_spad, NULL, block_size, ne0, src0_row_size_aligned, op_params);
+                break;
             case HTP_OP_RMS_NORM:
                 rms_norm_f32(src0_spad, dst_spad, NULL, block_size, ne0, src0_row_size_aligned, op_params);
                 break;
@@ -632,6 +726,9 @@ static int execute_op_unary_f32(struct htp_ops_context * octx) {
     const char * op_type = NULL;
 
     switch (octx->op) {
+        case HTP_OP_NORM:
+            op_type = "norm-f32";
+            break;
         case HTP_OP_RMS_NORM:
             op_type = "rmsnorm-f32";
             break;