Merge pull request #1631 from evoskuil/master

Optimize siphash and chain to_data() stream readers.

Author: evoskuil

include/bitcoin/system/impl/stream/iostream/istream.ipp

@@ -28,6 +28,7 @@ namespace system {
 
 // Allowed here for low level performance benefit.
 BC_PUSH_WARNING(NO_POINTER_ARITHMETIC)
+BC_PUSH_WARNING(NO_UNSAFE_COPY_N)
 
 template <typename Character>
 template <typename Buffer>
@@ -150,18 +151,19 @@ template <typename Character>
 void
 istream<Character>::read(char_type* data, std::streamsize count) NOEXCEPT
 {
-    const auto bytes = possible_narrow_sign_cast<size_t>(count);
+    auto bytes = possible_narrow_sign_cast<size_t>(count);
 
     if (is_overflow(bytes))
     {
+        if (state_ != goodbit)
+            return;
+
+        // Allow read to end if state was good (std::istream behavior).
+        bytes = end_ - position_;
         setstate(badbit);
-        return;
     }
 
-    BC_PUSH_WARNING(NO_UNSAFE_COPY_N)
     std::copy_n(position_, bytes, data);
-    BC_POP_WARNING()
-
     position_ += bytes;
 }
 
@@ -181,6 +183,7 @@ istream<Character>::is_overflow(pos_type size) const NOEXCEPT
     return (state_ != goodbit) || (size > (end_ - position_));
 }
 
+BC_POP_WARNING()
 BC_POP_WARNING()
 
 } // namespace system

src/chain/block.cpp

@@ -167,8 +167,9 @@ size_t block::get_allocation() const NOEXCEPT
 data_chunk block::to_data(bool witness) const NOEXCEPT
 {
     data_chunk data(serialized_size(witness));
-    stream::out::copy ostream(data);
-    to_data(ostream, witness);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out, witness);
     return data;
 }
 

src/chain/header.cpp

@@ -165,12 +165,9 @@ void header::assign_data(reader& source) NOEXCEPT
 data_chunk header::to_data() const NOEXCEPT
 {
     data_chunk data(serialized_size());
-
-    BC_PUSH_WARNING(NO_THROW_IN_NOEXCEPT)
-    stream::out::copy ostream(data);
-    BC_POP_WARNING()
-
-    to_data(ostream);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out);
     return data;
 }
 

src/chain/input.cpp

@@ -243,8 +243,9 @@ bool operator!=(const cref_point& left, const cref_point& right) NOEXCEPT
 data_chunk input::to_data() const NOEXCEPT
 {
     data_chunk data(serialized_size(false));
-    stream::out::copy ostream(data);
-    to_data(ostream);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out);
     return data;
 }
 

src/chain/operation.cpp

@@ -397,12 +397,9 @@ operation operation::from_string(const std::string& mnemonic) NOEXCEPT
 data_chunk operation::to_data() const NOEXCEPT
 {
     data_chunk data(serialized_size());
-
-    BC_PUSH_WARNING(NO_THROW_IN_NOEXCEPT)
-    stream::out::copy ostream(data);
-    BC_POP_WARNING()
-
-    to_data(ostream);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out);
     return data;
 }
 

src/chain/output.cpp

@@ -131,8 +131,9 @@ bool output::operator!=(const output& other) const NOEXCEPT
 data_chunk output::to_data() const NOEXCEPT
 {
     data_chunk data(serialized_size());
-    stream::out::copy ostream(data);
-    to_data(ostream);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out);
     return data;
 }
 

src/chain/point.cpp

@@ -156,12 +156,9 @@ void point::assign_data(reader& source) NOEXCEPT
 data_chunk point::to_data() const NOEXCEPT
 {
     data_chunk data(serialized_size());
-
-    BC_PUSH_WARNING(NO_THROW_IN_NOEXCEPT)
-    stream::out::copy ostream(data);
-    BC_POP_WARNING()
-
-    to_data(ostream);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out);
     return data;
 }
 

src/chain/script.cpp

@@ -307,8 +307,9 @@ script script::from_string(const std::string& mnemonic) NOEXCEPT
 data_chunk script::to_data(bool prefix) const NOEXCEPT
 {
     data_chunk data(serialized_size(prefix));
-    stream::out::copy ostream(data);
-    to_data(ostream, prefix);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out, prefix);
     return data;
 }
 

src/chain/transaction.cpp

@@ -243,8 +243,9 @@ data_chunk transaction::to_data(bool witness) const NOEXCEPT
     witness &= segregated_;
 
     data_chunk data(serialized_size(witness));
-    stream::out::copy ostream(data);
-    to_data(ostream, witness);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out, witness);
     return data;
 }
 

src/chain/witness.cpp

@@ -246,8 +246,9 @@ witness witness::from_string(const std::string& mnemonic) NOEXCEPT
 data_chunk witness::to_data(bool prefix) const NOEXCEPT
 {
     data_chunk data(serialized_size(prefix));
-    stream::out::copy ostream(data);
-    to_data(ostream, prefix);
+    stream::out::fast ostream(data);
+    write::bytes::fast out(ostream);
+    to_data(out, prefix);
     return data;
 }
 

src/hash/siphash.cpp

@@ -83,14 +83,16 @@ uint64_t siphash(const siphash_key& key,
 
     constexpr auto eight = sizeof(uint64_t);
     const auto bytes = message.size();
-    read::bytes::copy source(message);
+    stream::in::fast stream(message);
+    read::bytes::fast source(stream);
 
     for (size_t index = eight; index <= bytes; index += eight)
-        compression_round(v0, v1, v2, v3,
-            source.read_8_bytes_little_endian());
+        compression_round(v0, v1, v2, v3, source.read_8_bytes_little_endian());
 
-    auto last = is_zero(bytes % eight) ? 0_u64 :
-        source.read_8_bytes_little_endian();
+    // Read zero to seven remainder bytes (zero padded, fails stream).
+    BC_ASSERT(source);
+    auto last = source.read_8_bytes_little_endian();
+    BC_ASSERT(!source);
 
     last ^= ((bytes % max_encoded_byte_count) << to_bits(sub1(eight)));
     compression_round(v0, v1, v2, v3, last);