Add inlining for old optimizer.

libevmasm/Inliner.h

@@ -0,0 +1,83 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+// SPDX-License-Identifier: GPL-3.0
+/**
+ * @file Inliner.h
+ * Inlines small code snippets by replacing JUMP with a copy of the code jumped to.
+ */
+#pragma once
+
+#include <libsolutil/Common.h>
+#include <libevmasm/AssemblyItem.h>
+#include <liblangutil/EVMVersion.h>
+
+#include <range/v3/view/span.hpp>
+#include <map>
+#include <set>
+#include <vector>
+
+namespace solidity::evmasm
+{
+
+class Inliner
+{
+public:
+	explicit Inliner(
+		AssemblyItems& _items,
+		std::set<size_t> const& _tagsReferencedFromOutside,
+		size_t _runs,
+		bool _isCreation,
+		langutil::EVMVersion _evmVersion
+	):
+	m_items(_items),
+	m_tagsReferencedFromOutside(_tagsReferencedFromOutside),
+	m_runs(_runs),
+	m_isCreation(_isCreation),
+	m_evmVersion(_evmVersion)
+	{
+	}
+	virtual ~Inliner() = default;
+
+	void optimise();
+
+private:
+	struct InlinableBlock
+	{
+		ranges::span<AssemblyItem const> items;
+		uint64_t pushTagCount = 0;
+	};
+
+	/// @returns the exit jump type for the block to be inlined, if a particular jump to it should be inlined, otherwise nullopt.
+	std::optional<AssemblyItem::JumpType> shouldInline(size_t _tag, AssemblyItem const& _jump, InlinableBlock const& _block) const;
+	/// @returns true, if the full function at tag @a _tag with body @a _block that is referenced @a _pushTagCount times
+	/// should be inlined, false otherwise. @a _block should start at the first instruction after the function entry tag
+	/// up to and including the return jump.
+	bool shouldInlineFullFunctionBody(size_t _tag, ranges::span<AssemblyItem const> _block, uint64_t _pushTagCount) const;
+	/// @returns true, if the @a _items at @a _tag are a potential candidate for inlining.
+	bool isInlineCandidate(size_t _tag, ranges::span<AssemblyItem const> _items) const;
+	/// @returns a map from tags that can potentially be inlined to the inlinable item range behind that tag and the
+	/// number of times the tag in question was referenced.
+	std::map<size_t, InlinableBlock> determineInlinableBlocks(AssemblyItems const& _items) const;
+
+	AssemblyItems& m_items;
+	std::set<size_t> const& m_tagsReferencedFromOutside;
+	size_t const m_runs = 200;
+	bool const m_isCreation = false;
+	langutil::EVMVersion const m_evmVersion;
+};
+
+}