From 727e3f24bc57b9470b7972fe882d60117625afe5 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Wed, 7 Nov 2018 23:52:13 +0100
Subject: Do not perform cleanup on unsigned integers when loading from
 calldata.

---
 Changelog.md                          | 1 +
 libsolidity/codegen/CompilerUtils.cpp | 9 ++++++++-
 test/libsolidity/Assembly.cpp         | 2 +-
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/Changelog.md b/Changelog.md
index b5e7eed8..b2b03ae4 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -5,6 +5,7 @@ Language Features:
 
 Compiler Features:
  * Build System: LLL is not built anymore by default. Must configure it with CMake as `-DLLL=ON`.
+ * Code generator: Do not perform redundant double cleanup on unsigned integers when loading from calldata.
 
 
 Bugfixes:
diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index 90eb74fe..a0d11017 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -1236,6 +1236,7 @@ unsigned CompilerUtils::loadFromMemoryHelper(Type const& _type, bool _fromCallda
 	}
 	solAssert(numBytes <= 32, "Static memory load of more than 32 bytes requested.");
 	m_context << (_fromCalldata ? Instruction::CALLDATALOAD : Instruction::MLOAD);
+	bool cleanupNeeded = true;
 	if (isExternalFunctionType)
 		splitExternalFunctionType(true);
 	else if (numBytes != 32)
@@ -1245,10 +1246,16 @@ unsigned CompilerUtils::loadFromMemoryHelper(Type const& _type, bool _fromCallda
 		int shiftFactor = (32 - numBytes) * 8;
 		rightShiftNumberOnStack(shiftFactor);
 		if (leftAligned)
+		{
 			leftShiftNumberOnStack(shiftFactor);
+			cleanupNeeded = false;
+		}
+		else if (IntegerType const* intType = dynamic_cast<IntegerType const*>(&_type))
+			if (!intType->isSigned())
+				cleanupNeeded = false;
 	}
 	if (_fromCalldata)
-		convertType(_type, _type, true, false, true);
+		convertType(_type, _type, cleanupNeeded, false, true);
 
 	return numBytes;
 }
diff --git a/test/libsolidity/Assembly.cpp b/test/libsolidity/Assembly.cpp
index e815d7d5..5e157678 100644
--- a/test/libsolidity/Assembly.cpp
+++ b/test/libsolidity/Assembly.cpp
@@ -160,7 +160,7 @@ BOOST_AUTO_TEST_CASE(location_test)
 	AssemblyItems items = compileContract(sourceCode);
 	bool hasShifts = dev::test::Options::get().evmVersion().hasBitwiseShifting();
 	vector<SourceLocation> locations =
-		vector<SourceLocation>(hasShifts ? 23 : 24, SourceLocation(2, 82, make_shared<string>(""))) +
+		vector<SourceLocation>(hasShifts ? 21 : 22, SourceLocation(2, 82, make_shared<string>(""))) +
 		vector<SourceLocation>(2, SourceLocation(20, 79, make_shared<string>(""))) +
 		vector<SourceLocation>(1, SourceLocation(8, 17, make_shared<string>("--CODEGEN--"))) +
 		vector<SourceLocation>(3, SourceLocation(5, 7, make_shared<string>("--CODEGEN--"))) +
-- 
cgit