diff --git a/backprop/optimizer.cc b/backprop/optimizer.cc
index 5890190..93e3efe 100644
--- a/backprop/optimizer.cc
+++ b/backprop/optimizer.cc
@@ -27,6 +27,8 @@ namespace gcpp {
 
 namespace {
 
+using MatPtrF = MatPtrT<float>;
+
 // Split into two classes so that ForEachTensor only requires two "other"
 // arguments. This is anyway useful for locality, because `grad` only feeds
 // into `grad_m` and `grad_v` here.
@@ -40,12 +42,11 @@ class AdamUpdateMV {
         norm1_(1.0 / (1.0 - std::pow(beta1, t))),
         norm2_(1.0 / (1.0 - std::pow(beta2, t))) {}
 
-  void operator()(const MatPtr& grad, const MatPtr& grad_m,
-                  const MatPtr& grad_v) {
+  void operator()(const MatPtrF& grad, MatPtrF& grad_m, MatPtrF& grad_v) {
     for (size_t r = 0; r < grad.Rows(); ++r) {
-      const float* HWY_RESTRICT g = grad.RowT<float>(r);
-      float* HWY_RESTRICT m = grad_m.MutableRowT<float>(r);
-      float* HWY_RESTRICT v = grad_v.MutableRowT<float>(r);
+      const float* HWY_RESTRICT g = grad.Row(r);
+      float* HWY_RESTRICT m = grad_m.Row(r);
+      float* HWY_RESTRICT v = grad_v.Row(r);
       for (size_t c = 0; c < grad.Cols(); ++c) {
         m[c] *= beta1_;
         m[c] += cbeta1_ * g[c];
@@ -73,11 +74,12 @@ class AdamUpdateW {
         norm2_(1.0 / (1.0 - std::pow(beta2, t))),
         epsilon_(epsilon) {}
 
-  void operator()(MatPtr& weights, const MatPtr& grad_m, const MatPtr& grad_v) {
+  void operator()(MatPtrF& weights, const MatPtrF& grad_m,
+                  const MatPtrF& grad_v) {
     for (size_t r = 0; r < weights.Rows(); ++r) {
-      float* HWY_RESTRICT w = weights.RowT<float>(r);
-      const float* HWY_RESTRICT m = grad_m.RowT<float>(r);
-      const float* HWY_RESTRICT v = grad_v.RowT<float>(r);
+      float* HWY_RESTRICT w = weights.Row(r);
+      const float* HWY_RESTRICT m = grad_m.Row(r);
+      const float* HWY_RESTRICT v = grad_v.Row(r);
       for (size_t c = 0; c < weights.Cols(); ++c) {
         const float mhat = m[c] * norm1_;
         const float vhat = v[c] * norm2_;
@@ -100,12 +102,18 @@ void AdamUpdate(ModelWeightsPtrs<float>* grad, float alpha, float beta1,
                 ModelWeightsPtrs<float>* grad_v, hwy::ThreadPool& pool) {
   AdamUpdateMV update_mv(beta1, beta2, t);
   grad->ForEachTensor(grad_m, grad_v, [&update_mv](const TensorArgs& t) {
-    update_mv(t.mat, *t.other_mat1, *t.other_mat2);
+    const MatPtrF grad_f(t.mat);
+    MatPtrF grad_m_f(*t.other_mat1);
+    MatPtrF grad_v_f(*t.other_mat2);
+    update_mv(grad_f, grad_m_f, grad_v_f);
   });
 
   AdamUpdateW update_w(alpha, beta1, beta2, epsilon, t);
   weights->ForEachTensor(grad_m, grad_v, [&update_w](const TensorArgs& t) {
-    update_w(t.mat, *t.other_mat1, *t.other_mat2);
+    MatPtrF weights_f(t.mat);
+    const MatPtrF grad_m_f(*t.other_mat1);
+    const MatPtrF grad_v_f(*t.other_mat2);
+    update_w(weights_f, grad_m_f, grad_v_f);
   });
 }
 
diff --git a/gemma/activations.h b/gemma/activations.h
index 5f19dd8..489d7f4 100644
--- a/gemma/activations.h
+++ b/gemma/activations.h
@@ -33,8 +33,7 @@ struct Activations {
         layer_config(config.layer_configs[0]),
         seq_len(config.seq_len),
         cache_pos_size(config.CachePosSize()),
-        is_griffin(layer_config.type ==
-                   LayerAttentionType::kGriffinRecurrentBlock),
+        is_griffin(config.model == Model::GRIFFIN_2B),
 
         x("x", Extents2D(batch_size, config.model_dim), pad_),
         q("q",
@@ -58,21 +57,18 @@ struct Activations {
         C2("C2", Extents2D(batch_size, layer_config.ff_hidden_dim), pad_),
         ffw_out("ffw_out", Extents2D(batch_size, config.model_dim), pad_),
 
-        // No padding for Griffin because it does not always use Row().
         griffin_x("griffin_x",
                   is_griffin ? Extents2D(batch_size, config.model_dim) : none_,
-                  MatPadding::kPacked),
+                  pad_),
         griffin_y("griffin_y",
                   is_griffin ? Extents2D(batch_size, config.model_dim) : none_,
-                  MatPadding::kPacked),
+                  pad_),
         griffin_gate_x(
             "griffin_gate_x",
-            is_griffin ? Extents2D(batch_size, config.model_dim) : none_,
-            MatPadding::kPacked),
+            is_griffin ? Extents2D(batch_size, config.model_dim) : none_, pad_),
         griffin_multiplier(
             "griffin_mul",
-            is_griffin ? Extents2D(batch_size, config.model_dim) : none_,
-            MatPadding::kPacked),
+            is_griffin ? Extents2D(batch_size, config.model_dim) : none_, pad_),
 
         inv_timescale(CreateInvTimescale(
             ThreadingContext::Get().allocator, layer_config.qkv_dim,
diff --git a/gemma/gemma-inl.h b/gemma/gemma-inl.h
index 255d859..21e388f 100644
--- a/gemma/gemma-inl.h
+++ b/gemma/gemma-inl.h
@@ -21,7 +21,6 @@
 #include <stdio.h>
 
 #include <algorithm>  // std::min
-#include <memory>     // std::make_unique
 #include <vector>
 
 #include "gemma/activations.h"
@@ -69,30 +68,44 @@ namespace HWY_NAMESPACE {
 // Different functions use different naming conventions for the number of
 // tokens. Functions that are query-independent, such as RMSNorm*, call the
 // count `num_interleaved`. Functions that are query-dependent, such as
-// `Attention`, use separate `num_tokens` and `num_queries`.
+// `Attention`, use separate `num_tokens` and `num_queries`. `num_tokens` is the
+// number of tokens from one query: 1 for decode, otherwise prefill_tbatch_size.
 
-// TODO: add batch query support for Griffin (QueriesPos).
 template <typename T>
-HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
-                                   size_t layer, Activations& activations,
+HWY_NOINLINE void GriffinRecurrent(const QueriesPos& queries_pos,
+                                   size_t num_tokens, size_t griffin_layer,
+                                   Activations& activations,
                                    const LayerWeightsPtrs<T>* layer_weights,
                                    const KVCaches& kv_caches) {
   PROFILER_ZONE("Gen.Griffin");
-  KVCache& kv_cache = kv_caches[0];
   hwy::ThreadPool& pool = activations.env->ctx.pools.Pool(0);
   namespace hn = hwy::HWY_NAMESPACE;
   using D = hn::ScalableTag<float>;
+  const D df;
+
   const size_t model_dim = layer_weights->layer_config.model_dim;
-  const size_t conv_1d_width = layer_weights->layer_config.conv1d_width;
+  HWY_DASSERT(model_dim % hn::Lanes(df) == 0);
+
   const size_t heads = layer_weights->layer_config.heads;
+  const size_t conv_1d_width = layer_weights->layer_config.conv1d_width;
+  HWY_ASSERT_M(conv_1d_width % 2 == 0, "Conv width must be even");
+  const size_t kHeadDim = model_dim / heads;
+  const size_t kMatrixSize = kHeadDim * kHeadDim;
+
+  const size_t num_queries = queries_pos.size();
+  const hwy::Divisor div_num_q(static_cast<uint32_t>(num_queries));
+  const size_t num_interleaved = num_tokens * num_queries;
 
   // X / Y linear layers.
-  for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
-    float* HWY_RESTRICT y = activations.griffin_y.Row(batch_idx);
-    float* HWY_RESTRICT x = activations.griffin_x.Row(batch_idx);
+  // TODO: MatMul
+  HWY_DASSERT(activations.griffin_y.Rows() == activations.griffin_x.Rows());
+  HWY_DASSERT(num_interleaved == activations.griffin_y.Rows());
+  for (size_t r = 0; r < num_interleaved; ++r) {
+    float* HWY_RESTRICT y = activations.griffin_y.Row(r);
+    float* HWY_RESTRICT x = activations.griffin_x.Row(r);
     TwoMatVecAdd(layer_weights->griffin.linear_x_w,
                  layer_weights->griffin.linear_y_w, 0, model_dim, model_dim,
-                 activations.pre_att_rms_out.Row(batch_idx),
+                 activations.pre_att_rms_out.Row(r),
                  /*add0=*/layer_weights->griffin.linear_x_biases.PackedScale1(),
                  /*add1=*/layer_weights->griffin.linear_y_biases.PackedScale1(),
                  /*out0=*/x, /*out1=*/y, pool);
@@ -100,18 +113,19 @@ HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
   }
 
   // Conv1D.
-  for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
-    const size_t pos = batch_start + batch_idx;
-    float* HWY_RESTRICT x = activations.griffin_x.Row(batch_idx);
-    HWY_FULL(float) df;
-    HWY_DASSERT(model_dim % hn::Lanes(df) == 0);
+  for (size_t interleaved_idx = 0; interleaved_idx < num_interleaved;
+       ++interleaved_idx) {
+    const size_t query_idx = div_num_q.Remainder(interleaved_idx);
+    const size_t batch_idx = div_num_q.Divide(interleaved_idx);
+    const size_t pos = queries_pos[query_idx] + batch_idx;
+    float* HWY_RESTRICT x = activations.griffin_x.Row(query_idx);
 
     // cache[i] = input at time t-i.
     float* HWY_RESTRICT cache[kMaxConv1DWidth];
     cache[0] = x;
     for (size_t i = 1; i < conv_1d_width; i++) {
       cache[i] =
-          kv_cache.conv1d_cache.Row(layer) +
+          kv_caches[query_idx].conv1d_cache.Row(griffin_layer) +
           ((pos + conv_1d_width - 1 - i) % (conv_1d_width - 1)) * model_dim;
     }
     for (size_t i = 0; i < model_dim; i += hn::Lanes(df)) {
@@ -119,7 +133,6 @@ HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
       auto accum0 =
           hn::Load(df, layer_weights->griffin.conv_biases.PackedScale1() + i);
       auto accum1 = hn::Zero(df);
-      HWY_ASSERT_M(conv_1d_width % 2 == 0, "Conv width must be even");
       for (size_t l = 0; 2 * l < conv_1d_width; l++) {
         auto wv0 =
             hn::Load(df, layer_weights->griffin.conv_w.PackedScale1() +
@@ -136,17 +149,20 @@ HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
   }
 
   // RGLRU
-  for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
-    const size_t pos = batch_start + batch_idx;
-    float* HWY_RESTRICT y = activations.griffin_y.Row(batch_idx);
-    float* HWY_RESTRICT x = activations.griffin_x.Row(batch_idx);
-    float* HWY_RESTRICT gate_x = activations.griffin_gate_x.Row(batch_idx);
-    float* HWY_RESTRICT a = activations.griffin_multiplier.Row(batch_idx);
-    float* HWY_RESTRICT rnn_state = kv_cache.rglru_cache.Row(layer);
+  for (size_t interleaved_idx = 0; interleaved_idx < num_interleaved;
+       ++interleaved_idx) {
+    const size_t query_idx = div_num_q.Remainder(interleaved_idx);
+    const size_t batch_idx = div_num_q.Divide(interleaved_idx);
+    const size_t pos = queries_pos[query_idx] + batch_idx;
+
+    float* HWY_RESTRICT x = activations.griffin_x.Row(query_idx);
+    float* HWY_RESTRICT y = activations.griffin_y.Row(query_idx);
+    float* HWY_RESTRICT gate_x = activations.griffin_gate_x.Row(query_idx);
+    float* HWY_RESTRICT a = activations.griffin_multiplier.Row(query_idx);
+    float* HWY_RESTRICT rnn_state =
+        kv_caches[query_idx].rglru_cache.Row(griffin_layer);
 
     pool.Run(0, heads, [&](const uint64_t head, size_t /*thread*/) HWY_ATTR {
-      const size_t kHeadDim = model_dim / heads;
-      const size_t kMatrixSize = kHeadDim * kHeadDim;
       size_t head_offset = head * kHeadDim;
       TwoOfsMatVecAddLoop(
           layer_weights->griffin.gate_w, kMatrixSize * head,
@@ -166,7 +182,6 @@ HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
       hn::Transform1(D(), x + head_offset, kHeadDim, gate_x + head_offset,
                      fn_mul);
       // RNN scan
-      HWY_FULL(float) df;
       HWY_DASSERT(kHeadDim % hn::Lanes(df) == 0);
       for (size_t i = 0; i < kHeadDim; i += hn::Lanes(df)) {
         auto log_a = hn::Load(df, a + head_offset + i);
@@ -186,17 +201,18 @@ HWY_NOINLINE void GriffinRecurrent(size_t batch_start, size_t num_tokens,
         hn::Store(pre_out, df, x + head_offset + i);
       }
     });
-  }
+  }  // interleaved_idx
 
   // Final linear layer.
-  for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
-    float* HWY_RESTRICT x = activations.griffin_x.Row(batch_idx);
-    float* out_ptr = activations.att_sums.Row(batch_idx);
+  // TODO: MatMul
+  for (size_t r = 0; r < num_interleaved; ++r) {
+    float* HWY_RESTRICT x = activations.griffin_x.Row(r);
+    float* out_ptr = activations.att_sums.Row(r);
     MatVecAdd(layer_weights->griffin.linear_out_w, 0, model_dim, model_dim, x,
               layer_weights->griffin.linear_out_biases.PackedScale1(), out_ptr,
               pool);
   }
-}
+}  // GriffinRecurrent
 
 // Wrapper class; holds arguments in member variables to shorten call sites.
 template <typename T>
@@ -219,11 +235,7 @@ class GemmaAttention {
         activations_.weights_config.attention_window_sizes[layer] ==
         activations_.seq_len;
     // TODO: add a config flag instead of hardcoding the model.
-    if (is_global_layer &&
-        (activations_.weights_config.model == Model::GEMMA3_4B ||
-         activations_.weights_config.model == Model::GEMMA3_12B ||
-         activations_.weights_config.model == Model::GEMMA3_27B ||
-         activations_.weights_config.model == Model::GEMMA3_1B)) {
+    if (is_global_layer && IsVLM(activations_.weights_config.model)) {
       inv_timescale = activations_.inv_timescale_global.Packed();
     }
     // PostQKType::Rope
@@ -454,7 +466,6 @@ class GemmaAttention {
 
                 SingleDotSoftmaxWeightedSum(q, k, v, att, att_out, query_scale,
                                             pos, start_pos, last_pos);
-
               });
   }
 
@@ -587,14 +598,12 @@ HWY_NOINLINE void Attention(
     GemmaAttention<T>(queries_pos, queries_prefix_end, num_tokens, layer,
                       activations, layer_weights, div_seq_len, kv_caches)();
   } else {
-    // Only reached if the model is Griffin.
-    // The kv_caches are allocated only for the griffin layers, so we need to
-    // map the layer index to the griffin layer index.
-    auto type = layer_weights->layer_config.type;
-    size_t layer_of_type =
+    HWY_DASSERT(type == LayerAttentionType::kGriffinRecurrentBlock);
+    // KVCache conv1d_cache and rglru_cache have one row per *Griffin* layer,
+    // so map `layer` to the Griffin layer index.
+    const size_t griffin_layer =
         activations.weights_config.NumLayersOfTypeBefore(type, layer);
-    HWY_ASSERT(queries_pos.size() == 1);
-    GriffinRecurrent(queries_pos[0], num_tokens, layer_of_type, activations,
+    GriffinRecurrent(queries_pos, num_tokens, griffin_layer, activations,
                      layer_weights, kv_caches);
   }
 }
@@ -1056,7 +1065,6 @@ HWY_NOINLINE void Prefill(
   // threads to parallelizing over queries, but for simplicity we assign them
   // all to MatMul.
   const size_t max_tbatch_size = runtime_config.prefill_tbatch_size;
-  HWY_DASSERT(max_tbatch_size <= activations.x.Rows());
 
   // For each query. `qi` is within the batch, not the global query index.
   for (size_t qi = 0; qi < num_queries; ++qi) {
@@ -1397,6 +1405,7 @@ void GenerateT(const ModelStore& model, const ModelWeightsPtrs<T>& weights,
                const QueriesPos& queries_prefix_end,
                const size_t query_idx_start, const KVCaches& kv_caches,
                TimingInfo& timing_info) {
+  HWY_ASSERT(queries_pos_in.size() == kv_caches.size());
   // Griffin assumes that the recurrent block cache is zero-initialized.
   for (size_t i = 0; i < kv_caches.size(); ++i) {
     if (queries_pos_in[i] == 0) {
@@ -1510,17 +1519,10 @@ void GenerateBatchT(const ModelStore& model,
   const size_t num_queries = queries_prompt.size();
   HWY_ASSERT(queries_pos.size() == num_queries);
   HWY_ASSERT(kv_caches.size() >= num_queries);
-  // Griffin does not support query batching.
-  size_t max_qbatch_size = runtime_config.decode_qbatch_size;
-  for (const LayerConfig& layer_config : model.Config().layer_configs) {
-    if (layer_config.type == LayerAttentionType::kGriffinRecurrentBlock) {
-      max_qbatch_size = 1;
-      break;
-    }
-  }
-
+  const size_t max_qbatch_size = runtime_config.decode_qbatch_size;
   const size_t max_batch_size =
       HWY_MAX(max_qbatch_size, runtime_config.prefill_tbatch_size);
+
   Activations activations(model.Config(), max_batch_size, env);
 
   for (size_t qbatch_start = 0; qbatch_start < num_queries;
@@ -1528,7 +1530,6 @@ void GenerateBatchT(const ModelStore& model,
     // Generate one batch of tokens from `qbatch_size` queries.
     const size_t qbatch_size =
         HWY_MIN(num_queries - qbatch_start, max_qbatch_size);
-    activations.SetBatchSize(qbatch_size);
     const QueriesPromptTokens qbatch_prompts(&queries_prompt[qbatch_start],
                                              qbatch_size);
     QueriesPos qbatch_pos(&queries_pos[qbatch_start], qbatch_size);
diff --git a/gemma/kv_cache.cc b/gemma/kv_cache.cc
index 3992270..49dc31c 100644
--- a/gemma/kv_cache.cc
+++ b/gemma/kv_cache.cc
@@ -25,8 +25,9 @@
 namespace gcpp {
 
 void KVCache::ZeroGriffinCache() {
-  if (conv1d_cache.HasPtr()) ZeroInit(conv1d_cache);
-  if (rglru_cache.HasPtr()) ZeroInit(rglru_cache);
+  if (griffin_layers == 0) return;
+  ZeroInit(conv1d_cache);
+  ZeroInit(rglru_cache);
 }
 
 static size_t GriffinConv1dCols(const ModelConfig& config) {
@@ -34,7 +35,9 @@ static size_t GriffinConv1dCols(const ModelConfig& config) {
   for (const auto& layer_config : config.layer_configs) {
     conv1d_width = HWY_MAX(conv1d_width, layer_config.conv1d_width);
   }
-  return conv1d_width == 0 ? 0 : conv1d_width - 1;
+  // The row offset, in blocks of model_dim is computed mod (conv1d_width - 1),
+  // hence allocate conv1d_width * model_dim total columns.
+  return conv1d_width * config.model_dim;
 }
 
 // prefill_tbatch_size is the maximum number of tokens from one query to
@@ -42,12 +45,9 @@ static size_t GriffinConv1dCols(const ModelConfig& config) {
 KVCache::KVCache(const ModelConfig& config, size_t prefill_tbatch_size)
     : griffin_layers(
           config.NumLayersOfType(LayerAttentionType::kGriffinRecurrentBlock)),
-      griffin_conv1d_cols(GriffinConv1dCols(config)),
-      // TODO(patrickms): Add query batching support for Griffin.
-      conv1d_cache(
-          "conv1d_cache",
-          Extents2D(griffin_layers, griffin_conv1d_cols * config.model_dim),
-          MatPadding::kOdd),
+      conv1d_cache("conv1d_cache",
+                   Extents2D(griffin_layers, GriffinConv1dCols(config)),
+                   MatPadding::kOdd),
       rglru_cache("rglru_cache", Extents2D(griffin_layers, config.model_dim),
                   MatPadding::kOdd) {
   // TODO: move to MatStorageT.
diff --git a/gemma/kv_cache.h b/gemma/kv_cache.h
index f9707c8..014e75d 100644
--- a/gemma/kv_cache.h
+++ b/gemma/kv_cache.h
@@ -31,7 +31,6 @@ struct KVCache {
   KVCache Copy(const ModelConfig& weights_config, size_t prefill_tbatch_size);
 
   size_t griffin_layers = 0;
-  size_t griffin_conv1d_cols = 0;
   // griffin_layers, griffin_conv1d_cols * config.model_dim
   MatStorageT<float> conv1d_cache;
   MatStorageT<float> rglru_cache;  // griffin_layers, config.model_dim
diff --git a/gemma/weights.cc b/gemma/weights.cc
index 0269c60..4e8325d 100644
--- a/gemma/weights.cc
+++ b/gemma/weights.cc
@@ -97,21 +97,27 @@ void LayerWeightsPtrs<NuqStream>::Fixup(std::vector<MatOwner>& mat_owners) {
   SplitW1NUQ(layer_config);
 }
 
+struct TensorToRead {
+  MatPtr* mat;
+  BlobRange range;
+  // Some tensors opt out of padding via kNoPad flags.
+  MatPadding padding;
+};
+
 // Allocates multiple in parallel and binds to NUMA nodes.
-static void AllocateAndBindAll(const std::vector<MatPtr*>& mats,
-                               MatPadding padding,
+static void AllocateAndBindAll(const std::vector<TensorToRead>& tensors,
                                std::vector<MatOwner>& owners,
                                hwy::ThreadPool& pool) {
   const size_t start = owners.size();
-  owners.resize(start + mats.size());
+  owners.resize(start + tensors.size());
 
   MMParallel parallel(ThreadingContext::Get());
 
   // Allocate in parallel because faulting in large tensors is slow.
-  pool.Run(0, mats.size(), [&](uint64_t task, size_t /*thread*/) {
-    owners[start + task].AllocateFor(*mats[task], padding);
+  pool.Run(0, tensors.size(), [&](uint64_t task, size_t /*thread*/) {
+    owners[start + task].AllocateFor(*tensors[task].mat, tensors[task].padding);
     // TODO(janwas): MatMul outputs will later also be BF16.
-    BindB(*mats[task], sizeof(float), parallel);
+    BindB(*tensors[task].mat, sizeof(float), parallel);
   });
 }
 
@@ -155,55 +161,54 @@ MapPtr MapFileOrNull(File& file, uint64_t file_bytes) {
   return MapPtr();
 }
 
-static void MapAll(const std::vector<MatPtr*>& mats,
-                   const std::vector<BlobRange>& ranges, const MapPtr& mapped) {
+static void MapAll(const std::vector<TensorToRead>& tensors,
+                   const MapPtr& mapped) {
   PROFILER_ZONE("Startup.Weights.Map");
-  for (size_t i = 0; i < mats.size(); ++i) {
+  for (size_t i = 0; i < tensors.size(); ++i) {
     // SetPtr does not change the stride, but it is expected to be packed
     // because that is what Compress() writes to the file.
-    const size_t mat_bytes = mats[i]->PackedBytes();
+    const size_t mat_bytes = tensors[i].mat->PackedBytes();
     // Ensure blob size matches that computed from metadata.
-    HWY_ASSERT_M(mat_bytes == ranges[i].bytes, mats[i]->Name());
+    HWY_ASSERT_M(mat_bytes == tensors[i].range.bytes, tensors[i].mat->Name());
 
-    mats[i]->SetPtr(const_cast<uint8_t*>(mapped.get() + ranges[i].offset),
-                    mats[i]->Stride());
+    tensors[i].mat->SetPtr(
+        const_cast<uint8_t*>(mapped.get() + tensors[i].range.offset),
+        tensors[i].mat->Stride());
   }
 }
 
-std::vector<IOBatch> MakeBatches(const std::vector<BlobRange>& ranges,
-                                 const std::vector<MatPtr*>& mats,
+std::vector<IOBatch> MakeBatches(const std::vector<TensorToRead>& tensors,
                                  const uint64_t file_bytes) {
   PROFILER_ZONE("Startup.Weights.MakeBatches");
   // Batches must be contiguous but blobs are padded, hence at least one
   // batch per tensor, and more when tensor rows exceed the batch size.
   std::vector<IOBatch> batches;
-  batches.reserve(mats.size());
+  batches.reserve(tensors.size());
 
-  for (size_t i = 0; i < mats.size(); ++i) {
-    uint64_t offset = ranges[i].offset;
-    HWY_ASSERT(ranges[i].End() <= file_bytes);
+  for (size_t i = 0; i < tensors.size(); ++i) {
+    const BlobRange& range = tensors[i].range;
+    MatPtr& mat = *tensors[i].mat;
+    uint64_t offset = range.offset;
+    HWY_ASSERT(range.End() <= file_bytes);
 
-    batches.emplace_back(offset, ranges[i].key_idx);
-    const size_t file_bytes_per_row = mats[i]->Cols() * mats[i]->ElementBytes();
-    // Caution, `RowT` requires knowledge of the actual type. We instead use
-    // the first row, which is the same for any type, and advance the *byte*
-    // pointer by the *byte* stride.
-    const size_t mem_stride_bytes = mats[i]->Stride() * mats[i]->ElementBytes();
-    uint8_t* row = mats[i]->RowT<uint8_t>(0);
-    for (size_t r = 0; r < mats[i]->Rows(); ++r) {
-      if (!batches.back().Add(row, file_bytes_per_row)) {  // Full batch.
-        batches.emplace_back(offset, ranges[i].key_idx);
+    batches.emplace_back(offset, range.key_idx);
+    const size_t file_bytes_per_row = mat.Cols() * mat.ElementBytes();
+    const size_t mem_stride_bytes = mat.Stride() * mat.ElementBytes();
+    uint8_t* row_bytes = mat.RowBytes(0);
+    for (size_t r = 0; r < mat.Rows(); ++r) {
+      if (!batches.back().Add(row_bytes, file_bytes_per_row)) {  // Full batch.
+        batches.emplace_back(offset, range.key_idx);
         // Adding to an empty batch is always successful.
-        HWY_ASSERT(batches.back().Add(row, file_bytes_per_row));
+        HWY_ASSERT(batches.back().Add(row_bytes, file_bytes_per_row));
       }
       offset += file_bytes_per_row;
-      row += mem_stride_bytes;
+      row_bytes += mem_stride_bytes;
       // Keep the in-memory row padding uninitialized so msan detects any use.
     }
-    HWY_ASSERT(offset == ranges[i].End());
+    HWY_ASSERT(offset == range.End());
   }
 
-  HWY_ASSERT(batches.size() >= mats.size());
+  HWY_ASSERT(batches.size() >= tensors.size());
   return batches;
 }
 
@@ -228,16 +233,14 @@ static void ReadBatches(const BlobReader& reader,
 }
 
 // Aborts on error.
-static void MapOrReadAll(const std::vector<MatPtr*>& mats, BlobReader& reader,
-                         const std::vector<BlobRange>& ranges, Tristate map,
+static void MapOrReadAll(const std::vector<TensorToRead>& tensors,
+                         BlobReader& reader, Tristate map,
                          std::vector<MatOwner>& mat_owners,
-                         const MatPadding padding, hwy::ThreadPool& pool) {
-  HWY_ASSERT(mats.size() == ranges.size());
-
+                         hwy::ThreadPool& pool) {
   if (ChooseMode(reader.file_bytes(), map) == Mode::kMap) {
     MapPtr mapped = MapFileOrNull(reader.file(), reader.file_bytes());
     if (mapped) {
-      MapAll(mats, ranges, mapped);
+      MapAll(tensors, mapped);
       return;
     }
   }  // otherwise fall through to read mode
@@ -245,32 +248,32 @@ static void MapOrReadAll(const std::vector<MatPtr*>& mats, BlobReader& reader,
   {
     PROFILER_ZONE("Startup.Weights.Allocate");
     // NOTE: this changes the stride of `mats`!
-    AllocateAndBindAll(mats, padding, mat_owners, pool);
+    AllocateAndBindAll(tensors, mat_owners, pool);
   }
 
   const std::vector<IOBatch> batches =
-      MakeBatches(ranges, mats, reader.file_bytes());
+      MakeBatches(tensors, reader.file_bytes());
   ReadBatches(reader, batches, pool);
 }
 
 void WeightsOwner::ReadFromBlobs(const ModelStore& model, BlobReader& reader,
                                  Tristate map, hwy::ThreadPool& pool) {
   // List of tensors to read/map, and where from.
-  std::vector<MatPtr*> mats;
-  std::vector<BlobRange> ranges;
-
-  // Padding is inserted when reading row by row, except for NUQ tensors.
-  const MatPadding padding = MatPadding::kOdd;
+  std::vector<TensorToRead> tensors;
 
   AllocatePointer(model.Config());
 
   // Enumerate all weights (negligible cost).
   CallT([&](const auto& weights) {
     weights->ForEachTensor(nullptr, nullptr, [&](const TensorArgs& t) {
+      const MatPadding padding = (t.flags & TensorArgs::kNoPad)
+                                     ? MatPadding::kPacked
+                                     : MatPadding::kOdd;
       size_t key_idx;
       if (model.FindAndUpdateMatPtr(t.mat, key_idx)) {
-        mats.push_back(&t.mat);
-        ranges.push_back(reader.Range(key_idx));
+        tensors.push_back({.mat = &t.mat,
+                           .range = reader.Range(key_idx),
+                           .padding = padding});
         return;
       }
       if (t.flags & TensorArgs::kMaybeRead) return;  // optional and not found.
@@ -278,7 +281,7 @@ void WeightsOwner::ReadFromBlobs(const ModelStore& model, BlobReader& reader,
     });
   });
 
-  MapOrReadAll(mats, reader, ranges, map, mat_owners_, padding, pool);
+  MapOrReadAll(tensors, reader, map, mat_owners_, pool);
 
   Fixup(pool);
 }
@@ -338,9 +341,9 @@ void WeightsOwner::LogWeightStatsF32() {
           printf("[scale=%f] ", t.mat.Scale());
         }
         hwy::Stats stats;
-        HWY_ASSERT(t.mat.GetType() == Type::kF32);
+        const MatPtrT<float> mat_f(t.mat);
         for (size_t r = 0; r < t.mat.Rows(); ++r) {
-          const float* HWY_RESTRICT row = t.mat.RowT<float>(r);
+          const float* HWY_RESTRICT row = mat_f.Row(r);
           for (size_t c = 0; c < t.mat.Cols(); ++c) {
             stats.Notify(row[c]);
           }
diff --git a/gemma/weights.h b/gemma/weights.h
index aa184db..b0b24c2 100644
--- a/gemma/weights.h
+++ b/gemma/weights.h
@@ -43,24 +43,27 @@ struct TensorArgs {
   // name/type from another `LayerWeightsPtrs` for iterating over tensor pairs
   // (for copying) or triples (for `AdamUpdateMV`). Set by `TENSOR_ARGS`.
   // `flags` is a combination of zero or more `Flags`.
-  TensorArgs(MatPtr& mat, const MatPtr* other_mat1, const MatPtr* other_mat2,
-             int flags)
+  TensorArgs(MatPtr& mat, MatPtr* other_mat1, MatPtr* other_mat2, int flags)
       : mat(mat),
         other_mat1(other_mat1),
         other_mat2(other_mat2),
         flags(flags) {}
 
   MatPtr& mat;
-  const MatPtr* other_mat1;  // either/both can be nullptr.
-  const MatPtr* other_mat2;
+  MatPtr* other_mat1;  // either/both can be nullptr.
+  MatPtr* other_mat2;
 
-  // TODO: freestanding enum class instead? These are mutually exclusive.
   enum Flags {
-    // Read the tensor from the file and abort if it is not found.
+    // Default: Read the tensor from the file and abort if it is not found.
     kMustRead = 0,
+
     // Not an error if the tensor is not present in the file. For example,
     // the _w1/_w2 tensors are not always present.
     kMaybeRead = 1,
+
+    // Avoid padding tensor rows when reading. Used for some Griffin tensors
+    // whose index computations do not use Row() accessors.
+    kNoPad = 2,
   };
   const int flags;
 };
@@ -214,8 +217,8 @@ struct LayerWeightsPtrs {
   // can also iterate over pairs or triples of tensors for `AdamUpdateMV`.
   // Public because also called by `WeightsPtrs`.
   template <class Func>
-  void ForEachTensor(const LayerWeightsPtrs<Weight>* other1,
-                     const LayerWeightsPtrs<Weight>* other2, Func func) {
+  void ForEachTensor(LayerWeightsPtrs<Weight>* other1,
+                     LayerWeightsPtrs<Weight>* other2, Func func) {
     if (layer_config.type == LayerAttentionType::kVit) {
       // MHA.
       func(TENSOR_ARGS(vit.attn_out_w, kMustRead));
@@ -248,9 +251,9 @@ struct LayerWeightsPtrs {
       func(TENSOR_ARGS(griffin.linear_y_biases, kMustRead));
       func(TENSOR_ARGS(griffin.linear_out_w, kMustRead));
       func(TENSOR_ARGS(griffin.linear_out_biases, kMustRead));
-      func(TENSOR_ARGS(griffin.conv_w, kMustRead));
+      func(TENSOR_ARGS(griffin.conv_w, kMustRead | TensorArgs::kNoPad));
       func(TENSOR_ARGS(griffin.conv_biases, kMustRead));
-      func(TENSOR_ARGS(griffin.gate_w, kMustRead));
+      func(TENSOR_ARGS(griffin.gate_w, kMustRead | TensorArgs::kNoPad));
       func(TENSOR_ARGS(griffin.gate_biases, kMustRead));
       func(TENSOR_ARGS(griffin.a, kMustRead));
     }
@@ -363,8 +366,8 @@ struct LayerWeightsPtrs {
 
   // For FFN. Fast, only updates pointers.
   void SplitW1() {
-    // We only use this tensor for Gemma layers.
-    if (layer_config.type != LayerAttentionType::kGemma) return;
+    // Used for Gemma and Griffin layers; FFWVit uses different tensors.
+    if (layer_config.type == LayerAttentionType::kVit) return;
 
     // Files have both or neither of w1 and w2, and backprop/ allocates both.
     HWY_ASSERT(gating_einsum_w1.HasPtr() == gating_einsum_w2.HasPtr());
@@ -514,10 +517,10 @@ struct ModelWeightsPtrs {
   // used to copy from another set of weights. Public because called by tests
   // and `WeightsOwner`.
   template <class Func>
-  void ForEachTensor(const ModelWeightsPtrs<Weight>* other1,
-                     const ModelWeightsPtrs<Weight>* other2, Func func) {
-    const LayerWeightsPtrs<Weight>* other_layer1 = nullptr;
-    const LayerWeightsPtrs<Weight>* other_layer2 = nullptr;
+  void ForEachTensor(ModelWeightsPtrs<Weight>* other1,
+                     ModelWeightsPtrs<Weight>* other2, Func func) {
+    LayerWeightsPtrs<Weight>* other_layer1 = nullptr;
+    LayerWeightsPtrs<Weight>* other_layer2 = nullptr;
     func(TENSOR_ARGS(embedder_input_embedding, kMustRead));
     func(TENSOR_ARGS(final_norm_scale, kMustRead));
 
@@ -569,11 +572,12 @@ struct ModelWeightsPtrs {
 
   // Copies only the allocated tensors in `*this` from tensors in `other`.
   void CopyFrom(const ModelWeightsPtrs<Weight>& other) {
-    ForEachTensor(&other, nullptr, [](const TensorArgs& t) {
-      if (!t.mat.HasPtr()) return;
-      HWY_ASSERT(t.other_mat1 && t.other_mat1->HasPtr());
-      CopyMat(*t.other_mat1, t.mat);
-    });
+    ForEachTensor(const_cast<ModelWeightsPtrs<Weight>*>(&other), nullptr,
+                  [](const TensorArgs& t) {
+                    if (!t.mat.HasPtr()) return;
+                    HWY_ASSERT(t.other_mat1 && t.other_mat1->HasPtr());
+                    CopyMat(*t.other_mat1, t.mat);
+                  });
   }
 
   // Instead of reading, only allocates memory for all tensors. Used by
diff --git a/io/blob_store.cc b/io/blob_store.cc
index d0a0edb..6328a87 100644
--- a/io/blob_store.cc
+++ b/io/blob_store.cc
@@ -84,6 +84,14 @@ struct Header {             // standard layout class
 static_assert(sizeof(Header) == 16);
 }  // namespace
 
+// A write I/O request, each serviced by one thread in a pool.
+struct BlobIO {
+  BlobIO(BlobRange range, void* data) : range(range), data(data) {}
+
+  BlobRange range;
+  void* data;  // Read-only for writes.
+};
+
 // Little-endian on-disk representation: a fixed-size `Header`, then a padded
 // variable-length 'directory' of blob keys and their offset/sizes, then the
 // 'payload' of each blob's data with padding in between, followed by padding to
@@ -238,11 +246,11 @@ class BlobStore {
     return true;  // all OK
   }
 
-  void EnqueueWriteForHeaderAndDirectory(std::vector<BlobIO2>& writes) const {
+  void EnqueueWriteForHeaderAndDirectory(std::vector<BlobIO>& writes) const {
     const size_t key_idx = 0;  // not actually associated with a key/blob
     writes.emplace_back(
         BlobRange{.offset = 0, .bytes = sizeof(header_), .key_idx = key_idx},
-        // members are const and BlobIO2 requires non-const pointers, and they
+        // members are const and BlobIO requires non-const pointers, and they
         // are not modified by file writes.
         const_cast<Header*>(&header_));
     writes.emplace_back(
@@ -314,7 +322,7 @@ BlobReader::BlobReader(const Path& blob_path)
 
 // Split into chunks for load-balancing even if blob sizes vary.
 static void EnqueueChunks(size_t key_idx, uint64_t offset, uint64_t bytes,
-                          uint8_t* data, std::vector<BlobIO2>& writes) {
+                          uint8_t* data, std::vector<BlobIO>& writes) {
   constexpr size_t kChunkBytes = 4 * 1024 * 1024;
   const uint64_t end = offset + bytes;
   // Split into whole chunks and possibly one remainder.
@@ -336,7 +344,7 @@ static void EnqueueChunks(size_t key_idx, uint64_t offset, uint64_t bytes,
 static void EnqueueWritesForBlobs(const BlobStore& bs,
                                   const hwy::Span<const uint8_t> blobs[],
                                   std::vector<uint8_t>& zeros,
-                                  std::vector<BlobIO2>& writes) {
+                                  std::vector<BlobIO>& writes) {
   // All-zero buffer used to write padding to the file without copying the
   // input blobs.
   static constexpr uint8_t kZeros[kBlobAlign] = {0};
@@ -388,7 +396,7 @@ void BlobWriter::WriteAll(hwy::ThreadPool& pool, const Path& filename) {
   HWY_ASSERT(num_blobs != 0);
   HWY_ASSERT(num_blobs == blobs_.size());
 
-  std::vector<BlobIO2> writes;
+  std::vector<BlobIO> writes;
   writes.reserve(16384);
 
   const BlobStore bs(num_blobs, keys_.data(), blobs_.data());
diff --git a/io/blob_store.h b/io/blob_store.h
index 78bc08e..19c6639 100644
--- a/io/blob_store.h
+++ b/io/blob_store.h
@@ -44,16 +44,6 @@ struct BlobRange {
   size_t key_idx;
 };
 
-// A read or write I/O request, each serviced by one thread in a pool.
-struct BlobIO2 {
-  BlobIO2(BlobRange range, void* data) : range(range), data(data) {}
-
-  BlobRange range;
-  void* data;  // Modified only if a read request. Read-only for writes.
-};
-
-class BlobStore;
-
 // Reads `BlobStore` header, converts keys to strings and creates a hash map for
 // faster lookups.
 // TODO(janwas): rename to BlobFinder or similar.
diff --git a/ops/matmul.cc b/ops/matmul.cc
index 2f2f795..18af14e 100644
--- a/ops/matmul.cc
+++ b/ops/matmul.cc
@@ -425,7 +425,7 @@ MatMulEnv::MatMulEnv(ThreadingContext& ctx)
   have_timer_stop = hwy::platform::HaveTimerStop(cpu100);
 }
 
-void BindB(const MatPtr& B, size_t sizeof_TC, MMParallel& parallel) {
+void BindB(MatPtr& B, size_t sizeof_TC, MMParallel& parallel) {
   Allocator& allocator = parallel.allocator();
   if (!allocator.ShouldBind()) return;
   if (B.Rows() == 1) return;
@@ -437,8 +437,7 @@ void BindB(const MatPtr& B, size_t sizeof_TC, MMParallel& parallel) {
   for (size_t pkg_idx = 0; pkg_idx < ranges_np.NumTasks(); ++pkg_idx) {
     const IndexRange& rows_b = ranges_np.Range(pkg_idx);
     const size_t node = parallel.Node(pkg_idx);
-    uintptr_t begin =
-        reinterpret_cast<uintptr_t>(B.RowT<uint8_t>(rows_b.begin()));
+    uintptr_t begin = reinterpret_cast<uintptr_t>(B.RowBytes(rows_b.begin()));
     uintptr_t end = begin + rows_b.Num() * B.Stride() * B.ElementBytes();
     // B row padding is less than the page size, so only bind the subset that
     // is page-aligned.
@@ -451,7 +450,7 @@ void BindB(const MatPtr& B, size_t sizeof_TC, MMParallel& parallel) {
 }
 
 // C is BF16/float, or double for partial
-void BindC(const MatPtr& C, MMParallel& parallel) {
+void BindC(MatPtr& C, MMParallel& parallel) {
   Allocator& allocator = parallel.allocator();
   if (!allocator.ShouldBind()) return;
 
@@ -470,8 +469,7 @@ void BindC(const MatPtr& C, MMParallel& parallel) {
 
     const size_t node = parallel.Node(pkg_idx);
     for (size_t im = 0; im < C.Rows(); ++im) {
-      ok &= allocator.BindMemory(C.MutableRowT<uint8_t>(im) + begin,
-                                 end - begin, node);
+      ok &= allocator.BindMemory(C.RowBytes(im) + begin, end - begin, node);
     }
   }
   if (HWY_UNLIKELY(!ok)) {
diff --git a/ops/matmul.h b/ops/matmul.h
index fc4e8c1..c2474cb 100644
--- a/ops/matmul.h
+++ b/ops/matmul.h
@@ -172,9 +172,9 @@ class MMParallel {
   ThreadingContext& ctx_;
 };
 
-void BindB(const MatPtr& B, size_t sizeof_TC, MMParallel& parallel);
+void BindB(MatPtr& B, size_t sizeof_TC, MMParallel& parallel);
 // C is BF16/float, or double for partial.
-void BindC(const MatPtr& C, MMParallel& parallel);
+void BindC(MatPtr& C, MMParallel& parallel);
 
 // Per-package storage for packed A, and one global C-shaped `partial` for
 // accumulating partial dot products (sections of K).
diff --git a/util/mat.cc b/util/mat.cc
index 86baaee..28763ba 100644
--- a/util/mat.cc
+++ b/util/mat.cc
@@ -41,8 +41,8 @@ void CopyMat(const MatPtr& from, MatPtr& to) {
   }
   const size_t row_bytes = to.Cols() * to.ElementBytes();
   for (size_t r = 0; r < to.Rows(); ++r) {
-    const uint8_t* from_row = from.RowT<uint8_t>(r);
-    uint8_t* to_row = to.RowT<uint8_t>(r);
+    const uint8_t* from_row = from.RowBytes(r);
+    uint8_t* to_row = to.RowBytes(r);
     hwy::CopyBytes(from_row, to_row, row_bytes);
   }
 }
@@ -58,7 +58,7 @@ void ZeroInit(MatPtr& mat) {
   }
   const size_t row_bytes = mat.Cols() * mat.ElementBytes();
   for (size_t r = 0; r < mat.Rows(); ++r) {
-    hwy::ZeroBytes(mat.RowT<uint8_t>(r), row_bytes);
+    hwy::ZeroBytes(mat.RowBytes(r), row_bytes);
   }
 }
 
@@ -71,15 +71,19 @@ void RandInit(MatPtr& mat, float stddev, std::mt19937& gen) {
 
   std::normal_distribution<float> dist(0.0, stddev);
   if (mat.GetType() == Type::kF32) {
+    MatPtrT<float> mat_f(mat);
+
     for (size_t r = 0; r < mat.Rows(); ++r) {
-      float* HWY_RESTRICT row = mat.RowT<float>(r);
+      float* HWY_RESTRICT row = mat_f.Row(r);
       for (size_t c = 0; c < mat.Cols(); ++c) {
         row[c] = dist(gen);
       }
     }
   } else {
+    MatPtrT<double> mat_d(mat);
+
     for (size_t r = 0; r < mat.Rows(); ++r) {
-      double* HWY_RESTRICT row = mat.RowT<double>(r);
+      double* HWY_RESTRICT row = mat_d.Row(r);
       for (size_t c = 0; c < mat.Cols(); ++c) {
         row[c] = dist(gen);
       }
diff --git a/util/mat.h b/util/mat.h
index da662c9..0314e20 100644
--- a/util/mat.h
+++ b/util/mat.h
@@ -91,21 +91,14 @@ class MatPtr : public IFields {
     return num_elements_ * element_bytes_;
   }
 
-  // Works for any kind of padding.
-  template <typename T>
-  T* MutableRowT(size_t row) const {
+  // Works for any kind of padding and element type.
+  uint8_t* RowBytes(size_t row) {
     HWY_DASSERT(row < Rows());
-    return HWY_RCAST_ALIGNED(T*, ptr_) + row * stride_;
+    return static_cast<uint8_t*>(ptr_) + row * (stride_ * element_bytes_);
   }
-  template <typename T>
-  T* RowT(size_t row) {
+  const uint8_t* RowBytes(size_t row) const {
     HWY_DASSERT(row < Rows());
-    return HWY_RCAST_ALIGNED(T*, ptr_) + row * stride_;
-  }
-  template <typename T>
-  const T* RowT(size_t row) const {
-    HWY_DASSERT(row < Rows());
-    return HWY_RCAST_ALIGNED(const T*, ptr_) + row * stride_;
+    return static_cast<const uint8_t*>(ptr_) + row * (stride_ * element_bytes_);
   }
 
   Type GetType() const { return type_; }
@@ -209,9 +202,8 @@ class MatPtr : public IFields {
   float scale_ = 1.0f;  // multiplier for each value, for MatMul.
 };
 
-// Non-type erased version of `MatPtr`. Although `MatPtr` also provides
-// type-aware accessors (`RowT`), this class is more convenient when accessing
-// elements, and ensures the template argument and `Type` are consistent.
+// Non-type erased version of `MatPtr`: provides type-safe `Row()` and ensures
+// the template argument and `Type` are consistent.
 template <typename MatT>
 class MatPtrT : public MatPtr {
  public:
@@ -227,7 +219,9 @@ class MatPtrT : public MatPtr {
       : MatPtrT<MatT>(name.c_str(), ExtentsFromInfo(info.Find(name))) {}
 
   // Copying allowed because the metadata is small.
-  MatPtrT(const MatPtr& other) : MatPtr(other) {}
+  MatPtrT(const MatPtr& other) : MatPtr(other) {
+    HWY_ASSERT(other.GetType() == TypeEnum<MatT>());
+  }
   MatPtrT& operator=(const MatPtr& other) {
     MatPtr::operator=(other);
     return *this;
@@ -252,22 +246,24 @@ class MatPtrT : public MatPtr {
     return Packed();
   }
 
-  const MatT* Row(size_t row) const { return this->RowT<MatT>(row); }
-  MatT* Row(size_t row) { return this->RowT<MatT>(row); }
+  MatT* Row(size_t row) { return HWY_RCAST_ALIGNED(T*, RowBytes(row)); }
+  const MatT* Row(size_t row) const {
+    return HWY_RCAST_ALIGNED(const T*, RowBytes(row));
+  }
 
   PackedSpan<const MatT> PaddedSpan() const {
-    return MakeConstSpan(Row(0), Rows() * Stride());
+    return MakeConstSpan(HWY_RCAST_ALIGNED(MatT*, ptr_), Rows() * Stride());
   }
 
   // For `compress-inl.h` functions, which assume contiguous streams and thus
   // require packed layout.
-  PackedSpan<const MatT> Span() const {
-    HWY_ASSERT(IsPacked());
-    return MakeConstSpan(Row(0), num_elements_);
-  }
   PackedSpan<MatT> Span() {
     HWY_ASSERT(IsPacked());
-    return MakeSpan(Row(0), num_elements_);
+    return MakeSpan(HWY_RCAST_ALIGNED(MatT*, ptr_), num_elements_);
+  }
+  PackedSpan<const MatT> Span() const {
+    HWY_ASSERT(IsPacked());
+    return MakeConstSpan(HWY_RCAST_ALIGNED(MatT*, ptr_), num_elements_);
   }
 };