[yul-phaser] ProgramCache::calculateTotalCachedCodeSize(): Replace de…

…fault weights with ones that better correlate with memory usage
sunxunxunxun · May 20, 2020 · 1fa689e · 1fa689e
1 parent bff012c
commit 1fa689e
Show file tree

Hide file tree

Showing 3 changed files with 31 additions and 6 deletions.
diff --git a/test/yulPhaser/ProgramCache.cpp b/test/yulPhaser/ProgramCache.cpp
@@ -214,11 +214,11 @@ BOOST_FIXTURE_TEST_CASE(startRound_should_remove_entries_older_than_two_rounds,
 
 BOOST_FIXTURE_TEST_CASE(gatherStats_should_return_cache_statistics, ProgramCacheFixture)
 {
-	size_t sizeI = optimisedProgram(m_program, "I").codeSize(CodeWeights{});
-	size_t sizeIu = optimisedProgram(m_program, "Iu").codeSize(CodeWeights{});
-	size_t sizeIuO = optimisedProgram(m_program, "IuO").codeSize(CodeWeights{});
-	size_t sizeL = optimisedProgram(m_program, "L").codeSize(CodeWeights{});
-	size_t sizeLT = optimisedProgram(m_program, "LT").codeSize(CodeWeights{});
+	size_t sizeI = optimisedProgram(m_program, "I").codeSize(CacheStats::StorageWeights);
+	size_t sizeIu = optimisedProgram(m_program, "Iu").codeSize(CacheStats::StorageWeights);
+	size_t sizeIuO = optimisedProgram(m_program, "IuO").codeSize(CacheStats::StorageWeights);
+	size_t sizeL = optimisedProgram(m_program, "L").codeSize(CacheStats::StorageWeights);
+	size_t sizeLT = optimisedProgram(m_program, "LT").codeSize(CacheStats::StorageWeights);
 
 	m_programCache.optimiseProgram("L");
 	m_programCache.optimiseProgram("Iu");

diff --git a/tools/yulPhaser/ProgramCache.cpp b/tools/yulPhaser/ProgramCache.cpp
@@ -135,7 +135,7 @@ size_t ProgramCache::calculateTotalCachedCodeSize() const
 {
 	size_t size = 0;
 	for (auto const& pair: m_entries)
-		size += pair.second.program.codeSize(CodeWeights{});
+		size += pair.second.program.codeSize(CacheStats::StorageWeights);
 
 	return size;
 }

diff --git a/tools/yulPhaser/ProgramCache.h b/tools/yulPhaser/ProgramCache.h
@@ -19,6 +19,8 @@
 
 #include <tools/yulPhaser/Program.h>
 
+#include <libyul/optimiser/Metrics.h>
+
 #include <map>
 #include <string>
 
@@ -44,6 +46,29 @@ struct CacheEntry
  */
 struct CacheStats
 {
+	/// Weights used to compute totalCodeSize.
+	/// The goal here is to get a result proportional to the amount of memory taken by the AST.
+	/// Each statement/expression gets 1 just for existing. We add more if it contains any extra
+	/// data that won't be visited separately by ASTWalker.
+	static yul::CodeWeights constexpr StorageWeights = {
+		/* expressionStatementCost = */ 1,
+		/* assignmentCost = */ 1,
+		/* variableDeclarationCost = */ 1,
+		/* functionDefinitionCost = */ 1,
+		/* ifCost = */ 1,
+		/* switchCost = */ 1,
+		/* caseCost = */ 1,
+		/* forLoopCost = */ 1,
+		/* breakCost = */ 1,
+		/* continueCost = */ 1,
+		/* leaveCost = */ 1,
+		/* blockCost = */ 1,
+
+		/* functionCallCost = */ 1,
+		/* identifierCost = */ 1,
+		/* literalCost = */ 1,
+	};
+
 	size_t hits;
 	size_t misses;
 	size_t totalCodeSize;