optimise reading/writing for contiguous arrays

KrisThielemans · KrisThielemans · commit 10f61f03f0a0 · 2024-05-17T13:09:12.000+01:00
diff --git a/src/include/stir/IO/read_data.h b/src/include/stir/IO/read_data.h
@@ -2,6 +2,7 @@
 #define __stir_IO_read_data_H__
 /*
     Copyright (C) 2004- 2007, Hammersmith Imanet Ltd
+    Copyright (C) 2024, University College London
     This file is part of STIR.
 
     SPDX-License-Identifier: Apache-2.0
diff --git a/src/include/stir/IO/read_data.inl b/src/include/stir/IO/read_data.inl
@@ -1,5 +1,6 @@
 /*
     Copyright (C) 2004- 2007, Hammersmith Imanet Ltd
+    Copyright (C) 2024, University College London
     This file is part of STIR.
 
     SPDX-License-Identifier: Apache-2.0
@@ -34,6 +35,10 @@ template <int num_dimensions, class IStreamT, class elemT>
 inline Succeeded
 read_data_help(is_not_1d, IStreamT& s, Array<num_dimensions, elemT>& data, const ByteOrder byte_order)
 {
+  if (data.is_contiguous())
+    return read_data_1d(s, data, byte_order);
+
+  // otherwise, recurse
   for (typename Array<num_dimensions, elemT>::iterator iter = data.begin(); iter != data.end(); ++iter)
     {
       if (read_data(s, *iter, byte_order) == Succeeded::no)
diff --git a/src/include/stir/IO/read_data_1d.h b/src/include/stir/IO/read_data_1d.h
@@ -34,15 +34,15 @@ namespace detail
 
   This function might propagate any exceptions by std::istream::read.
  */
-template <class elemT>
-inline Succeeded read_data_1d(std::istream& s, Array<1, elemT>& data, const ByteOrder byte_order);
+template <int num_dimensions, class elemT>
+inline Succeeded read_data_1d(std::istream& s, Array<num_dimensions, elemT>& data, const ByteOrder byte_order);
 
 /* \ingroup Array_IO_detail
   \brief  This is the (internal) function that does the actual reading from a FILE*.
   \internal
  */
-template <class elemT>
-inline Succeeded read_data_1d(FILE*&, Array<1, elemT>& data, const ByteOrder byte_order);
+template <int num_dimensions, class elemT>
+inline Succeeded read_data_1d(FILE*&, Array<num_dimensions, elemT>& data, const ByteOrder byte_order);
 
 } // end namespace detail
 END_NAMESPACE_STIR
diff --git a/src/include/stir/IO/read_data_1d.inl b/src/include/stir/IO/read_data_1d.inl
@@ -27,9 +27,9 @@ namespace detail
 
 /***************** version for istream *******************************/
 
-template <class elemT>
+template <int num_dimensions, class elemT>
 Succeeded
-read_data_1d(std::istream& s, Array<1, elemT>& data, const ByteOrder byte_order)
+read_data_1d(std::istream& s, Array<num_dimensions, elemT>& data, const ByteOrder byte_order)
 {
   if (!s || (dynamic_cast<std::ifstream*>(&s) != 0 && !dynamic_cast<std::ifstream*>(&s)->is_open())
       || (dynamic_cast<std::fstream*>(&s) != 0 && !dynamic_cast<std::fstream*>(&s)->is_open()))
@@ -41,9 +41,9 @@ read_data_1d(std::istream& s, Array<1, elemT>& data, const ByteOrder byte_order)
   // note: find num_to_read (using size()) outside of s.read() function call
   // otherwise Array::check_state() in size() might abort if
   // get_data_ptr() is called before size() (which is compiler dependent)
-  const std::streamsize num_to_read = static_cast<std::streamsize>(data.size()) * sizeof(elemT);
-  s.read(reinterpret_cast<char*>(data.get_data_ptr()), num_to_read);
-  data.release_data_ptr();
+  const std::streamsize num_to_read = static_cast<std::streamsize>(data.size_all()) * sizeof(elemT);
+  s.read(reinterpret_cast<char*>(data.get_full_data_ptr()), num_to_read);
+  data.release_full_data_ptr();
 
   if (!s)
     {
@@ -53,8 +53,8 @@ read_data_1d(std::istream& s, Array<1, elemT>& data, const ByteOrder byte_order)
 
   if (!byte_order.is_native_order())
     {
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data[i]);
+      for (auto iter = data.begin_all(); iter != data.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   return Succeeded::yes;
@@ -63,9 +63,9 @@ read_data_1d(std::istream& s, Array<1, elemT>& data, const ByteOrder byte_order)
 /***************** version for FILE *******************************/
 // largely a copy of above, but with calls to stdio function
 
-template <class elemT>
+template <int num_dimensions, class elemT>
 Succeeded
-read_data_1d(FILE*& fptr_ref, Array<1, elemT>& data, const ByteOrder byte_order)
+read_data_1d(FILE*& fptr_ref, Array<num_dimensions, elemT>& data, const ByteOrder byte_order)
 {
   FILE* fptr = fptr_ref;
   if (fptr == NULL || ferror(fptr))
@@ -77,9 +77,9 @@ read_data_1d(FILE*& fptr_ref, Array<1, elemT>& data, const ByteOrder byte_order)
   // note: find num_to_read (using size()) outside of s.read() function call
   // otherwise Array::check_state() in size() might abort if
   // get_data_ptr() is called before size() (which is compiler dependent)
-  const std::size_t num_to_read = static_cast<std::size_t>(data.size());
-  const std::size_t num_read = fread(reinterpret_cast<char*>(data.get_data_ptr()), sizeof(elemT), num_to_read, fptr);
-  data.release_data_ptr();
+  const std::size_t num_to_read = static_cast<std::size_t>(data.size_all());
+  const std::size_t num_read = fread(reinterpret_cast<char*>(data.get_full_data_ptr()), sizeof(elemT), num_to_read, fptr);
+  data.release_full_data_ptr();
 
   if (ferror(fptr) || num_to_read != num_read)
     {
@@ -89,8 +89,8 @@ read_data_1d(FILE*& fptr_ref, Array<1, elemT>& data, const ByteOrder byte_order)
 
   if (!byte_order.is_native_order())
     {
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data[i]);
+      for (auto iter = data.begin_all(); iter != data.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   return Succeeded::yes;
diff --git a/src/include/stir/IO/write_data_1d.h b/src/include/stir/IO/write_data_1d.h
@@ -35,19 +35,19 @@ namespace detail
   This function does not throw any exceptions. Exceptions thrown by std::ostream::write
   are caught.
  */
-template <class elemT>
+template <int num_dimensions, class elemT>
 inline Succeeded
-write_data_1d(std::ostream& s, const Array<1, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data);
+write_data_1d(std::ostream& s, const Array<num_dimensions, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data);
 /*! \ingroup Array_IO_detail
   \brief This is an internal function called by \c write_data(). It does the actual writing
    to \c FILE* using stdio functions.
 
   This function does not throw any exceptions.
 
  */
-template <class elemT>
+template <int num_dimensions, class elemT>
 inline Succeeded
-write_data_1d(FILE*& fptr_ref, const Array<1, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data);
+write_data_1d(FILE*& fptr_ref, const Array<num_dimensions, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data);
 } // namespace detail
 
 END_NAMESPACE_STIR
diff --git a/src/include/stir/IO/write_data_1d.inl b/src/include/stir/IO/write_data_1d.inl
@@ -27,9 +27,9 @@ namespace detail
 
 /***************** version for ostream *******************************/
 
-template <class elemT>
+template <int num_dimensions, class elemT>
 inline Succeeded
-write_data_1d(std::ostream& s, const Array<1, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data)
+write_data_1d(std::ostream& s, const Array<num_dimensions, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data)
 {
   if (!s || (dynamic_cast<std::ofstream*>(&s) != 0 && !dynamic_cast<std::ofstream*>(&s)->is_open())
       || (dynamic_cast<std::fstream*>(&s) != 0 && !dynamic_cast<std::fstream*>(&s)->is_open()))
@@ -44,40 +44,40 @@ write_data_1d(std::ostream& s, const Array<1, elemT>& data, const ByteOrder byte
   /*
   if (!byte_order.is_native_order())
   {
-  Array<1, elemT> a_copy(data);
+  Array<num_dimensions, elemT> a_copy(data);
   for(int i=data.get_min_index(); i<=data.get_max_index(); i++)
   ByteOrder::swap_order(a_copy[i]);
   return write_data(s, a_copy, ByteOrder::native, true);
   }
   */
   if (!byte_order.is_native_order())
     {
-      Array<1, elemT>& data_ref = const_cast<Array<1, elemT>&>(data);
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data_ref[i]);
+      Array<num_dimensions, elemT>& data_ref = const_cast<Array<num_dimensions, elemT>&>(data);
+      for (auto iter = data_ref.begin_all(); iter != data_ref.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   // note: find num_to_write (using size()) outside of s.write() function call
   // otherwise Array::check_state() in size() might abort if
   // get_const_data_ptr() is called before size() (which is compiler dependent)
-  const std::streamsize num_to_write = static_cast<std::streamsize>(data.size()) * sizeof(elemT);
+  const std::streamsize num_to_write = static_cast<std::streamsize>(data.size_all()) * sizeof(elemT);
   bool writing_ok = true;
   try
     {
-      s.write(reinterpret_cast<const char*>(data.get_const_data_ptr()), num_to_write);
+      s.write(reinterpret_cast<const char*>(data.get_const_full_data_ptr()), num_to_write);
     }
   catch (...)
     {
       writing_ok = false;
     }
 
-  data.release_const_data_ptr();
+  data.release_const_full_data_ptr();
 
   if (!can_corrupt_data && !byte_order.is_native_order())
     {
-      Array<1, elemT>& data_ref = const_cast<Array<1, elemT>&>(data);
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data_ref[i]);
+      Array<num_dimensions, elemT>& data_ref = const_cast<Array<num_dimensions, elemT>&>(data);
+      for (auto iter = data_ref.begin_all(); iter != data_ref.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   if (!writing_ok || !s)
@@ -92,9 +92,9 @@ write_data_1d(std::ostream& s, const Array<1, elemT>& data, const ByteOrder byte
 /***************** version for FILE *******************************/
 // largely a copy of above, but with calls to stdio function
 
-template <class elemT>
+template <int num_dimensions, class elemT>
 inline Succeeded
-write_data_1d(FILE*& fptr_ref, const Array<1, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data)
+write_data_1d(FILE*& fptr_ref, const Array<num_dimensions, elemT>& data, const ByteOrder byte_order, const bool can_corrupt_data)
 {
   FILE* fptr = fptr_ref;
   if (fptr == 0 || ferror(fptr))
@@ -109,33 +109,33 @@ write_data_1d(FILE*& fptr_ref, const Array<1, elemT>& data, const ByteOrder byte
   /*
   if (!byte_order.is_native_order())
   {
-  Array<1, elemT> a_copy(data);
+  Array<num_dimensions, elemT> a_copy(data);
   for(int i=data.get_min_index(); i<=data.get_max_index(); i++)
   ByteOrder::swap_order(a_copy[i]);
   return write_data(s, a_copy, ByteOrder::native, true);
   }
   */
   if (!byte_order.is_native_order())
     {
-      Array<1, elemT>& data_ref = const_cast<Array<1, elemT>&>(data);
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data_ref[i]);
+      Array<num_dimensions, elemT>& data_ref = const_cast<Array<num_dimensions, elemT>&>(data);
+      for (auto iter = data_ref.begin_all(); iter != data_ref.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   // note: find num_to_write (using size()) outside of s.write() function call
   // otherwise Array::check_state() in size() might abort if
   // get_const_data_ptr() is called before size() (which is compiler dependent)
-  const std::size_t num_to_write = static_cast<std::size_t>(data.size());
+  const std::size_t num_to_write = static_cast<std::size_t>(data.size_all());
   const std::size_t num_written
-      = fwrite(reinterpret_cast<const char*>(data.get_const_data_ptr()), sizeof(elemT), num_to_write, fptr);
+      = fwrite(reinterpret_cast<const char*>(data.get_const_full_data_ptr()), sizeof(elemT), num_to_write, fptr);
 
-  data.release_const_data_ptr();
+  data.release_const_full_data_ptr();
 
   if (!can_corrupt_data && !byte_order.is_native_order())
     {
-      Array<1, elemT>& data_ref = const_cast<Array<1, elemT>&>(data);
-      for (int i = data.get_min_index(); i <= data.get_max_index(); ++i)
-        ByteOrder::swap_order(data_ref[i]);
+      Array<num_dimensions, elemT>& data_ref = const_cast<Array<num_dimensions, elemT>&>(data);
+      for (auto iter = data_ref.begin_all(); iter != data_ref.end_all(); ++iter)
+        ByteOrder::swap_order(*iter);
     }
 
   if (num_written != num_to_write || ferror(fptr))
