[luci/pass] Introduce FuseMulWithFullyConnectedPass

compiler/luci/pass/include/luci/CircleOptimizer.h

@@ -49,6 +49,7 @@ class CircleOptimizer final
       FuseMeanWithMean,
       FuseMulWithConv,
       FuseMulWithDiv,
+      FuseMulWithFullyConnected,
       FuseTransposeWithMean,
       ResolveCustomOpAdd,
       ResolveCustomOpBatchMatMul,

compiler/luci/pass/include/luci/Pass/FuseMulWithFullyConnectedPass.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2024 Samsung Electronics Co., Ltd. All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LUCI_FUSE_MUL_WITH_FULLYCONNECTED_PASS_H__
+#define __LUCI_FUSE_MUL_WITH_FULLYCONNECTED_PASS_H__
+
+#include <logo/Pass.h>
+
+namespace luci
+{
+
+/**
+ * @brief  Class to fuse Mul into CircleFullyConnected
+ */
+struct FuseMulWithFullyConnectedPass final : public logo::Pass
+{
+  const char *name(void) const final { return "luci::FuseMulWithFullyConnectedPass"; }
+
+  bool run(loco::Graph *g) final;
+};
+
+} // namespace luci
+
+#endif // __LUCI_FUSE_MUL_WITH_FULLYCONNECTED_PASS_H__

compiler/luci/pass/src/CircleOptimizer.cpp

@@ -48,6 +48,7 @@
 #include "luci/Pass/FuseMeanWithMeanPass.h"
 #include "luci/Pass/FuseMulWithConvPass.h"
 #include "luci/Pass/FuseMulWithDivPass.h"
+#include "luci/Pass/FuseMulWithFullyConnectedPass.h"
 #include "luci/Pass/FusePreActivationBatchNormPass.h"
 #include "luci/Pass/FusePReluPass.h"
 #include "luci/Pass/FuseGeluPass.h"
@@ -310,6 +311,10 @@ void CircleOptimizer::optimize(loco::Graph *g) const
   {
     phase.emplace_back(std::make_unique<FuseMulWithDivPass>());
   }
+  if (_options->query(Options::Algorithm::FuseMulWithFullyConnected))
+  {
+    phase.emplace_back(std::make_unique<FuseMulWithFullyConnectedPass>());
+  }
   if (_options->query(Options::Algorithm::ResolveCustomOpMaxPoolWithArgmax))
   {
     phase.emplace_back(std::make_unique<luci::ResolveCustomOpMaxPoolWithArgmaxPass>());

compiler/luci/pass/src/FuseMulWithFullyConnectedPass.cpp

@@ -0,0 +1,242 @@
+/*
+ * Copyright (c) 2024 Samsung Electronics Co., Ltd. All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "luci/Pass/FuseMulWithFullyConnectedPass.h"
+
+#include "helpers/NodeFiller.h"
+
+#include <luci/IR/CircleNodes.h>
+#include <luci/Service/Nodes/CircleConst.h>
+#include <luci/Profile/CircleNodeOrigin.h>
+
+namespace
+{
+
+#define RETURN_FALSE_UNLESS(cond) \
+  if (not(cond))                  \
+    return false;
+
+inline bool is_single_element(const luci::CircleConst *node)
+{
+  return ((node->rank() == 1 || node->rank() == 0) && node->size<loco::DataType::FLOAT32>() == 1);
+}
+
+inline void update_with_single_element(luci::CircleConst *fused_node,
+                                       const luci::CircleConst *multiplication)
+{
+  for (uint32_t i = 0; i < fused_node->size<loco::DataType::FLOAT32>(); i++)
+  {
+    fused_node->at<loco::DataType::FLOAT32>(i) *= multiplication->at<loco::DataType::FLOAT32>(0);
+  }
+}
+
+luci::CircleConst *gen_fused_weights(luci::CircleConst *weights,
+                                     const luci::CircleConst *multiplication)
+{
+  auto fused_weights = luci::clone(weights);
+  // Single element multiplication:
+  if (is_single_element(multiplication))
+  {
+    update_with_single_element(fused_weights, multiplication);
+  }
+  // N-size multiplication:
+  else
+  {
+    // Go along channels, multiplication size is ensured to be compatible with channels.
+    auto count = fused_weights->dim(0).value();
+    auto size = fused_weights->dim(fused_weights->rank() - 1).value();
+    float val;
+    for (uint32_t c = 0; c < count; c++)
+    {
+      val = multiplication->at<loco::DataType::FLOAT32>(c);
+      for (uint32_t i = 0; i < size; i++)
+      {
+        fused_weights->at<loco::DataType::FLOAT32>(c * size + i) *= val;
+      }
+    }
+  }
+  return fused_weights;
+}
+
+luci::CircleConst *gen_fused_bias(luci::CircleConst *bias, const luci::CircleConst *multiplication)
+{
+  auto fused_bias = luci::clone(bias);
+  // Single element multiplication:
+  if (is_single_element(multiplication))
+  {
+    update_with_single_element(fused_bias, multiplication);
+  }
+  // N-size multiplication:
+  else
+  {
+    // Go along channels, multiplication size is ensured to be compatible with channels.
+    for (uint32_t i = 0; i < fused_bias->size<loco::DataType::FLOAT32>(); i++)
+    {
+      fused_bias->at<loco::DataType::FLOAT32>(i) *= multiplication->at<loco::DataType::FLOAT32>(i);
+    }
+  }
+  return fused_bias;
+}
+
+/**
+ *  Fuse Mul to FullyConnected if the multiplied value is a channel(last dimension)-wise constant
+ *
+ *  BEFORE
+ *                |
+ *      [CircleFullyConnected]
+ *                |
+ *           [CircleMul]
+ *                |
+ *
+ *  AFTER
+ *                |
+ *       [CircleFullyConnected]   [CircleMul] (dead)
+ *                |
+ *
+ */
+bool fuse_mul_with_fc(luci::CircleMul *mul)
+{
+  // Sanity check:
+  RETURN_FALSE_UNLESS(mul);
+  // Allow Mul node only with FLOAT32 data type:
+  RETURN_FALSE_UNLESS(mul->dtype() == loco::DataType::FLOAT32);
+  // Check if any FC node connects to Mul.
+  // Find the pattern of Mul(FC, CircleConst):
+  luci::CircleFullyConnected *fc = nullptr;
+  luci::CircleConst *multiplication = nullptr;
+  RETURN_FALSE_UNLESS(luci::fill(&fc, &multiplication).with_commutative_args_of(mul));
+  /**
+   *  Make sure that FullyConnected has only one successor.
+   *
+   *  If the FullyConnected output is connected to more nodes,
+   *  this pass will replace node with new fused FullyConnected.
+   *  Thus pass success will only introduce extra FullyConnected
+   *  without reducing overall number of nodes.
+   *  Which tends to increase model's size and degrades model's performance.
+   *  Thus one successor is required to benefit from this pass.
+   *
+   *  Example graph that illustrates the described scenario:
+   *
+   *  BEFORE
+   *                |
+   *      [CircleFullyConnected]
+   *                |
+   *        +-------+----------------+
+   *        |                        |
+   *        |                        |
+   *  [Other Node]              [CircleMul]
+   *        |                        |
+   *
+   *  AFTER
+   *                |
+   *                +-----------------------+
+   *                |                       |
+   *                |                       |
+   *      [CircleFullyConnected]            |
+   *                |                       |
+   *        +-------+                       |
+   *        |                               |
+   *        |                               |
+   *  [Other Node]       [New CircleFullyConnected Fused with Mul]
+   *        |                               |
+   *
+   */
+  RETURN_FALSE_UNLESS(loco::succs(fc).size() == 1);
+  // Allow only FLOAT32 data type:
+  RETURN_FALSE_UNLESS(fc->dtype() == loco::DataType::FLOAT32);
+  // Allow only without activation functions as values are going to
+  // be multiplied before activation function.
+  RETURN_FALSE_UNLESS(fc->fusedActivationFunction() == luci::FusedActFunc::NONE);
+  // Check for weights being Constant:
+  auto weights = dynamic_cast<luci::CircleConst *>(fc->weights());
+  RETURN_FALSE_UNLESS(weights);
+  // Get rank of multiplication:
+  auto rank = multiplication->rank();
+  // Check that all dimensions are ones, checks broadcast capabilites.
+  // Last dimesion of multiplication must be compatible with FC.
+  // N-D case (N>1):
+  if (multiplication->rank() > 1)
+  {
+    // Check channel-wise broadcasting:
+    for (uint32_t i = 0; i < rank - 1; i++)
+      RETURN_FALSE_UNLESS(multiplication->dim(i).value() == 1);
+    // Check the last dimesion of Mul is the same with the first dimension of FullyConnected
+    RETURN_FALSE_UNLESS(multiplication->dim(rank - 1) == weights->dim(0));
+  }
+  // 1-D or scalar case:
+  else if (multiplication->rank() == 1)
+  {
+    RETURN_FALSE_UNLESS(multiplication->size<loco::DataType::FLOAT32>() == 1 ||
+                        multiplication->size<loco::DataType::FLOAT32>() == weights->dim(0));
+  }
+  else if (multiplication->rank() == 0)
+  {
+    RETURN_FALSE_UNLESS(multiplication->size<loco::DataType::FLOAT32>() == 1);
+  }
+
+  // Only supports:
+  // (1) constant bias
+  // (2) no bias
+  auto bias = loco::must_cast<luci::CircleNode *>(fc->bias());
+  if (bias->opcode() == luci::CircleOpcode::CIRCLECONST)
+  {
+    // Create new bias to be updated with values:
+    auto const_bias = dynamic_cast<luci::CircleConst *>(fc->bias());
+    RETURN_FALSE_UNLESS(const_bias)
+    RETURN_FALSE_UNLESS(const_bias->dtype() == loco::DataType::FLOAT32);
+    // Create new bias with updated values and replace:
+    auto fused_bias = gen_fused_bias(const_bias, multiplication);
+    fc->bias(fused_bias);
+  }
+  else if (bias->opcode() != luci::CircleOpcode::CIRCLEOUTPUTEXCLUDE)
+  {
+    return false;
+  }
+
+  // Create new weights with updated values and replace:
+  auto fused_weights = gen_fused_weights(weights, multiplication);
+  fc->weights(fused_weights);
+
+  // Set origin and copy Activation Function if exisitng:
+  fc->fusedActivationFunction(mul->fusedActivationFunction());
+  luci::add_origin(fc, luci::get_origin(mul));
+
+  replace(mul).with(fc);
+
+  return true;
+}
+
+} // namespace
+
+namespace luci
+{
+
+bool FuseMulWithFullyConnectedPass::run(loco::Graph *g)
+{
+  bool changed = false;
+  for (auto node : loco::active_nodes(loco::output_nodes(g)))
+  {
+    if (auto mul = dynamic_cast<luci::CircleMul *>(node))
+    {
+      if (fuse_mul_with_fc(mul))
+        changed = true;
+    }
+  }
+
+  return changed;
+}
+
+} // namespace luci