diff options
author | William Casarin <jb55@jb55.com> | 2020-05-01 17:31:38 -0700 |
---|---|---|
committer | William Casarin <jb55@jb55.com> | 2020-05-15 15:26:54 -0700 |
commit | 83a425d25af033086744c1c8c892015014ed46bd (patch) | |
tree | 1fd1094b3c5c37aa900b49b496e0d1c40468b7b6 | |
parent | 844d2070a2c0106bb7a54be5cad7d4da4d9cd55e (diff) | |
download | bitcoin-83a425d25af033086744c1c8c892015014ed46bd.tar.xz |
compressor: use a prevector in compressed script serialization
Use a prevector for stack allocation instead of heap allocation during
script compression and decompression. These functions were doing
millions of unnecessary heap allocations during IBD.
We introduce a CompressedScript type alias for this prevector. It is
size 33 as that is the maximum size of a compressed script.
Fix the DecompressScript header to match the variable name from
compressor.cpp
Signed-off-by: William Casarin <jb55@jb55.com>
-rw-r--r-- | src/compressor.cpp | 4 | ||||
-rw-r--r-- | src/compressor.h | 20 | ||||
-rw-r--r-- | src/test/compress_tests.cpp | 8 | ||||
-rw-r--r-- | src/test/fuzz/script.cpp | 8 |
4 files changed, 27 insertions, 13 deletions
diff --git a/src/compressor.cpp b/src/compressor.cpp index a70306d320..ef3135e7a5 100644 --- a/src/compressor.cpp +++ b/src/compressor.cpp @@ -52,7 +52,7 @@ static bool IsToPubKey(const CScript& script, CPubKey &pubkey) return false; } -bool CompressScript(const CScript& script, std::vector<unsigned char> &out) +bool CompressScript(const CScript& script, CompressedScript& out) { CKeyID keyID; if (IsToKeyID(script, keyID)) { @@ -92,7 +92,7 @@ unsigned int GetSpecialScriptSize(unsigned int nSize) return 0; } -bool DecompressScript(CScript& script, unsigned int nSize, const std::vector<unsigned char> &in) +bool DecompressScript(CScript& script, unsigned int nSize, const CompressedScript& in) { switch(nSize) { case 0x00: diff --git a/src/compressor.h b/src/compressor.h index 478bfff0b6..40b2496f06 100644 --- a/src/compressor.h +++ b/src/compressor.h @@ -6,14 +6,26 @@ #ifndef BITCOIN_COMPRESSOR_H #define BITCOIN_COMPRESSOR_H +#include <prevector.h> #include <primitives/transaction.h> #include <script/script.h> #include <serialize.h> #include <span.h> -bool CompressScript(const CScript& script, std::vector<unsigned char> &out); +/** + * This saves us from making many heap allocations when serializing + * and deserializing compressed scripts. + * + * This prevector size is determined by the largest .resize() in the + * CompressScript function. The largest compressed script format is a + * compressed public key, which is 33 bytes. + */ +using CompressedScript = prevector<33, unsigned char>; + + +bool CompressScript(const CScript& script, CompressedScript& out); unsigned int GetSpecialScriptSize(unsigned int nSize); -bool DecompressScript(CScript& script, unsigned int nSize, const std::vector<unsigned char> &out); +bool DecompressScript(CScript& script, unsigned int nSize, const CompressedScript& in); /** * Compress amount. @@ -51,7 +63,7 @@ struct ScriptCompression template<typename Stream> void Ser(Stream &s, const CScript& script) { - std::vector<unsigned char> compr; + CompressedScript compr; if (CompressScript(script, compr)) { s << MakeSpan(compr); return; @@ -66,7 +78,7 @@ struct ScriptCompression unsigned int nSize = 0; s >> VARINT(nSize); if (nSize < nSpecialScripts) { - std::vector<unsigned char> vch(GetSpecialScriptSize(nSize), 0x00); + CompressedScript vch(GetSpecialScriptSize(nSize), 0x00); s >> MakeSpan(vch); DecompressScript(script, nSize, vch); return; diff --git a/src/test/compress_tests.cpp b/src/test/compress_tests.cpp index df1a119d79..4bc301f583 100644 --- a/src/test/compress_tests.cpp +++ b/src/test/compress_tests.cpp @@ -72,7 +72,7 @@ BOOST_AUTO_TEST_CASE(compress_script_to_ckey_id) CScript script = CScript() << OP_DUP << OP_HASH160 << ToByteVector(pubkey.GetID()) << OP_EQUALVERIFY << OP_CHECKSIG; BOOST_CHECK_EQUAL(script.size(), 25); - std::vector<unsigned char> out; + CompressedScript out; bool done = CompressScript(script, out); BOOST_CHECK_EQUAL(done, true); @@ -89,7 +89,7 @@ BOOST_AUTO_TEST_CASE(compress_script_to_cscript_id) script << OP_HASH160 << ToByteVector(CScriptID(redeemScript)) << OP_EQUAL; BOOST_CHECK_EQUAL(script.size(), 23); - std::vector<unsigned char> out; + CompressedScript out; bool done = CompressScript(script, out); BOOST_CHECK_EQUAL(done, true); @@ -107,7 +107,7 @@ BOOST_AUTO_TEST_CASE(compress_script_to_compressed_pubkey_id) CScript script = CScript() << ToByteVector(key.GetPubKey()) << OP_CHECKSIG; // COMPRESSED_PUBLIC_KEY_SIZE (33) BOOST_CHECK_EQUAL(script.size(), 35); - std::vector<unsigned char> out; + CompressedScript out; bool done = CompressScript(script, out); BOOST_CHECK_EQUAL(done, true); @@ -124,7 +124,7 @@ BOOST_AUTO_TEST_CASE(compress_script_to_uncompressed_pubkey_id) CScript script = CScript() << ToByteVector(key.GetPubKey()) << OP_CHECKSIG; // PUBLIC_KEY_SIZE (65) BOOST_CHECK_EQUAL(script.size(), 67); // 1 char code + 65 char pubkey + OP_CHECKSIG - std::vector<unsigned char> out; + CompressedScript out; bool done = CompressScript(script, out); BOOST_CHECK_EQUAL(done, true); diff --git a/src/test/fuzz/script.cpp b/src/test/fuzz/script.cpp index de82122dd6..63fff7d2ba 100644 --- a/src/test/fuzz/script.cpp +++ b/src/test/fuzz/script.cpp @@ -36,7 +36,7 @@ void test_one_input(const std::vector<uint8_t>& buffer) if (!script_opt) return; const CScript script{*script_opt}; - std::vector<unsigned char> compressed; + CompressedScript compressed; if (CompressScript(script, compressed)) { const unsigned int size = compressed[0]; compressed.erase(compressed.begin()); @@ -94,10 +94,12 @@ void test_one_input(const std::vector<uint8_t>& buffer) { const std::vector<uint8_t> bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider); + CompressedScript compressed_script; + compressed_script.assign(bytes.begin(), bytes.end()); // DecompressScript(..., ..., bytes) is not guaranteed to be defined if the bytes vector is too short - if (bytes.size() >= 32) { + if (compressed_script.size() >= 32) { CScript decompressed_script; - DecompressScript(decompressed_script, fuzzed_data_provider.ConsumeIntegral<unsigned int>(), bytes); + DecompressScript(decompressed_script, fuzzed_data_provider.ConsumeIntegral<unsigned int>(), compressed_script); } } |