Transport debug data through common subexpression eliminator

libyul/optimiser/CommonSubexpressionEliminator.cpp

@@ -120,6 +120,25 @@ void CommonSubexpressionEliminator::visit(Expression& _e)
 				// We check for syntactic equality again because the value might have changed.
 				if (inScope(variable) && SyntacticallyEqual{}(_e, *value->value))
 				{
+					if (debugDataOf(*value->value))
+					{
+						langutil::DebugData::Attributes mergedDebugAttributes;
+						if (debugDataOf(*value->value)->attributes.has_value())
+							mergedDebugAttributes = debugDataOf(*value->value)->attributes;
+						if (debugDataOf(_e) && mergedDebugAttributes.has_value())
+						{
+							for (auto const& i: debugDataOf(_e)->attributes.value())
+								mergedDebugAttributes->emplace_back(i);
+							_e = Identifier{
+								langutil::DebugData::create(
+									debugDataOf(_e)->nativeLocation,
+									debugDataOf(_e)->originLocation,
+									debugDataOf(_e)->astID,
+									mergedDebugAttributes),
+								variable};
+							break;
+						}
+					}
 					_e = Identifier{debugDataOf(_e), variable};
 					break;
 				}

test/libyul/YulOptimizerAssemblyTest.cpp

@@ -19,12 +19,14 @@
 #include <test/libyul/YulOptimizerAssemblyTest.h>
 #include <test/libyul/YulOptimizerTestCommon.h>
 
+#include <test/libsolidity/util/SoltestErrors.h>
 #include <test/libyul/Common.h>
 #include <test/Common.h>
 
 #include <libyul/Object.h>
 #include <libyul/AsmPrinter.h>
 
+#include <liblangutil/CharStreamProvider.h>
 #include <liblangutil/SourceReferenceFormatter.h>
 #include <liblangutil/Scanner.h>
 
@@ -60,6 +62,10 @@ YulOptimizerAssemblyTest::YulOptimizerAssemblyTest(std::string const& _filename)
 	m_optimizerStep = std::prev(std::prev(path.end()))->string();
 
 	m_source = m_reader.source();
+
+	auto dialectName = m_reader.stringSetting("dialect", "evm");
+	m_dialect = &dialect(dialectName, solidity::test::CommonOptions::get().evmVersion());
+
 	m_expectation = m_reader.simpleExpectations();
 }
 
@@ -104,3 +110,26 @@ TestCase::TestResult YulOptimizerAssemblyTest::run(std::ostream& _stream, std::s
 
 	return checkResult(_stream, _linePrefix, _formatted);
 }
+
+std::pair<std::shared_ptr<Object>, std::shared_ptr<AsmAnalysisInfo>> YulOptimizerAssemblyTest::parse(
+	std::ostream& _stream,
+	std::string const& _linePrefix,
+	bool const _formatted,
+	std::string const& _source
+)
+{
+	ErrorList errors;
+	soltestAssert(m_dialect, "");
+	std::shared_ptr<Object> object;
+	std::shared_ptr<AsmAnalysisInfo> analysisInfo;
+	std::tie(object, analysisInfo) = yul::test::parse(_source, *m_dialect, errors);
+	if (!object || !analysisInfo || Error::containsErrors(errors))
+	{
+		AnsiColorized(_stream, _formatted, {formatting::BOLD, formatting::RED}) << _linePrefix << "Error parsing source." << std::endl;
+		CharStream charStream(_source, "");
+		SourceReferenceFormatter{_stream, SingletonCharStreamProvider(charStream), true, false}
+			.printErrorInformation(errors);
+		return {};
+	}
+	return {std::move(object), std::move(analysisInfo)};
+}

test/libyul/YulOptimizerAssemblyTest.h

@@ -48,7 +48,16 @@ class YulOptimizerAssemblyTest: public solidity::frontend::test::EVMVersionRestr
 
 	TestResult run(std::ostream& _stream, std::string const& _linePrefix = "", bool const _formatted = false) override;
 private:
+	std::pair<std::shared_ptr<Object>, std::shared_ptr<AsmAnalysisInfo>> parse(
+		std::ostream& _stream, std::string const& _linePrefix, bool const _formatted, std::string const& _source
+	);
+
 	std::string m_optimizerStep;
+
+	Dialect const* m_dialect = nullptr;
+
+	std::shared_ptr<Object> m_object;
+	std::shared_ptr<AsmAnalysisInfo> m_analysisInfo;
 };
 
 }

test/libyul/yulOptimizerAssemblyTests/commonSubexpressionEliminator/basic.yul

@@ -0,0 +1,24 @@
+{
+    let a := /** @debug.set {"assignment":"a"} */ mul(1, codesize()) /** @debug.set {} */
+    let b := /** @debug.set {"assignment":"b"} */ mul(1, codesize()) /** @debug.set {} */
+}
+// ----
+// step: commonSubexpressionEliminator
+//
+// {
+//     let a := /** @debug.set {"assignment":"a"} */ mul(1, codesize())
+//     let b := a
+// }
+//
+// Assembly:
+//     /* "":59:69   */
+//   codesize   // @debug.set {"assignment":"a"}
+//     /* "":56:57   */
+//   0x01   // @debug.set {"assignment":"a"}
+//     /* "":52:70   */
+//   mul   // @debug.set {"assignment":"a"}
+//     /* "":142:160   */
+//   dup1   // @debug.set [{"assignment":"a"},{"assignment":"b"}]
+//     /* "":0:183   */
+//   pop
+//   pop

test/libyul/yulOptimizerAssemblyTests/commonSubexpressionEliminator/function.yul

@@ -0,0 +1,66 @@
+{
+    function f(a, b)
+    {
+    }
+    let x := /** @debug.set {"id": 0} */ 42 /** @debug.set {} */
+    let y := /** @debug.set {"id":" 1"} */ add(sload(42), calldataload(0)) /** @debug.set {} */
+    let z := /** @debug.set {"id":"2"} */ 42 /** @debug.set {} */
+    f(/** @debug.set {"f": 0} */ 42, /** @debug.set {"f": 1} */add(sload(42), /** @debug.set {"f": 2} */calldataload(0))) /** @debug.set {} */
+}
+// ----
+// step: commonSubexpressionEliminator
+//
+// {
+//     let x := /** @debug.set {"id":0} */ 42
+//     let y := /** @debug.set {"id":" 1"} */ add(sload(x), /** @debug.set {"id":" 1"} */ calldataload(0))
+//     let z := x
+//     f(x, /** @debug.set {"f":1} */ add(sload(x), /** @debug.set {"f":2} */ calldataload(0)))
+//     function f(a, b)
+//     { }
+// }
+//
+// Assembly:
+//     /* "":76:78   */
+//   0x2a   // @debug.set {"id":0}
+//     /* "":171:172   */
+//   0x00   // @debug.set {"id":" 1"}
+//     /* "":158:173   */
+//   calldataload   // @debug.set {"id":" 1"}
+//     /* "":153:155   */
+//   dup2   // @debug.set [{"id":0},{"id":" 1"}]
+//     /* "":147:156   */
+//   sload   // @debug.set {"id":" 1"}
+//     /* "":143:174   */
+//   add   // @debug.set {"id":" 1"}
+//     /* "":238:240   */
+//   dup2   // @debug.set [{"id":0},{"id":"2"}]
+//     /* "":266:383   */
+//   tag_2
+//     /* "":379:380   */
+//   0x00   // @debug.set {"f":2}
+//     /* "":366:381   */
+//   calldataload   // @debug.set {"f":2}
+//     /* "":335:337   */
+//   dup5   // @debug.set [{"id":0},{"f":1}]
+//     /* "":329:338   */
+//   sload   // @debug.set {"f":1}
+//     /* "":325:382   */
+//   add   // @debug.set {"f":1}
+//     /* "":295:297   */
+//   dup5   // @debug.set [{"id":0},{"f":0}]
+//     /* "":266:383   */
+//   tag_1
+//   jump	// in
+// tag_2:
+//     /* "":6:34   */
+//   jump(tag_3)
+// tag_1:
+//   pop
+//   pop
+// tag_4:
+//   jump	// out
+// tag_3:
+//     /* "":0:406   */
+//   pop
+//   pop
+//   pop