Remove obsolete main function yul optimiser step.

libyul/CMakeLists.txt

@@ -128,8 +128,6 @@ add_library(yul
 	optimiser/LoadResolver.h
 	optimiser/LoopInvariantCodeMotion.cpp
 	optimiser/LoopInvariantCodeMotion.h
-	optimiser/MainFunction.cpp
-	optimiser/MainFunction.h
 	optimiser/Metrics.cpp
 	optimiser/Metrics.h
 	optimiser/NameCollector.cpp

libyul/optimiser/MainFunction.cpp

@@ -1,54 +0,0 @@
-/*
-	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
-/**
- * Changes the topmost block to be a function with a specific name ("main") which has no
- * inputs nor outputs.
- */
-
-#include <libyul/optimiser/MainFunction.h>
-
-#include <libyul/optimiser/NameCollector.h>
-#include <libyul/Exceptions.h>
-
-#include <libyul/AST.h>
-
-#include <libsolutil/CommonData.h>
-
-using namespace std;
-using namespace solidity;
-using namespace solidity::yul;
-
-void MainFunction::operator()(Block& _block)
-{
-	assertThrow(_block.statements.size() >= 1, OptimizerException, "");
-	assertThrow(holds_alternative<Block>(_block.statements[0]), OptimizerException, "");
-	for (size_t i = 1; i < _block.statements.size(); ++i)
-		assertThrow(holds_alternative<FunctionDefinition>(_block.statements.at(i)), OptimizerException, "");
-	/// @todo this should handle scopes properly and instead of an assertion it should rename the conflicting function
-	assertThrow(NameCollector(_block).names().count("main"_yulstring) == 0, OptimizerException, "");
-
-	Block& block = std::get<Block>(_block.statements[0]);
-	FunctionDefinition main{
-		block.debugData,
-		"main"_yulstring,
-		{},
-		{},
-		std::move(block)
-	};
-	_block.statements[0] = std::move(main);
-}

libyul/optimiser/MainFunction.h

@@ -1,47 +0,0 @@
-/*
-	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
-/**
- * Changes the topmost block to be a function with a specific name ("main") which has no
- * inputs nor outputs.
- */
-
-#pragma once
-
-#include <libyul/ASTForward.h>
-
-namespace solidity::yul
-{
-
-struct OptimiserStepContext;
-
-/**
- * Prerequisites: Function Grouper
- */
-class MainFunction
-{
-public:
-	static constexpr char const* name{"MainFunction"};
-	static void run(OptimiserStepContext&, Block& _ast) { MainFunction{}(_ast); }
-
-	void operator()(Block& _block);
-
-private:
-	MainFunction() = default;
-};
-
-}

test/libyul/YulOptimizerTestCommon.cpp

@@ -40,7 +40,6 @@
 #include <libyul/optimiser/ForLoopInitRewriter.h>
 #include <libyul/optimiser/LoadResolver.h>
 #include <libyul/optimiser/LoopInvariantCodeMotion.h>
-#include <libyul/optimiser/MainFunction.h>
 #include <libyul/optimiser/StackLimitEvader.h>
 #include <libyul/optimiser/NameDisplacer.h>
 #include <libyul/optimiser/Rematerialiser.h>
@@ -174,11 +173,6 @@ YulOptimizerTestCommon::YulOptimizerTestCommon(
 			FunctionGrouper::run(*m_context, *m_ast);
 			FullInliner::run(*m_context, *m_ast);
 		}},
-		{"mainFunction", [&]() {
-			disambiguate();
-			FunctionGrouper::run(*m_context, *m_ast);
-			MainFunction::run(*m_context, *m_ast);
-		}},
 		{"rematerialiser", [&]() {
 			disambiguate();
 			ForLoopInitRewriter::run(*m_context, *m_ast);

test/libyul/yulOptimizerTests/mainFunction/empty_block.yul

@@ -1,28 +0,0 @@
-{
-    let a:u256
-    { }
-    function f() -> x:bool {
-        let b:u256 := 4:u256
-        {}
-        for {} f() {} {}
-    }
-}
-// ====
-// dialect: yul
-// ----
-// step: mainFunction
-//
-// {
-//     function main()
-//     {
-//         let a
-//         { }
-//     }
-//     function f() -> x:bool
-//     {
-//         let b := 4
-//         { }
-//         for { } f() { }
-//         { }
-//     }
-// }

test/libyul/yulOptimizerTests/mainFunction/multi_fun_mixed.yul

@@ -1,24 +0,0 @@
-{
-    let a:u256
-    function f() { let b:u256 }
-    let c:u256
-    function g() { let d:u256 }
-    let e:u256
-}
-// ====
-// dialect: yul
-// ----
-// step: mainFunction
-//
-// {
-//     function main()
-//     {
-//         let a
-//         let c
-//         let e
-//     }
-//     function f()
-//     { let b }
-//     function g()
-//     { let d }
-// }

test/libyul/yulOptimizerTests/mainFunction/nested_fun.yul

@@ -1,24 +0,0 @@
-{
-    let a:u256
-    function f() {
-        let b:u256
-        function g() { let c:u256}
-        let d:u256
-    }
-}
-// ====
-// dialect: yul
-// ----
-// step: mainFunction
-//
-// {
-//     function main()
-//     { let a }
-//     function f()
-//     {
-//         let b
-//         function g()
-//         { let c }
-//         let d
-//     }
-// }

test/libyul/yulOptimizerTests/mainFunction/single_fun.yul

@@ -1,15 +0,0 @@
-{
-    let a:u256
-    function f() {}
-}
-// ====
-// dialect: yul
-// ----
-// step: mainFunction
-//
-// {
-//     function main()
-//     { let a }
-//     function f()
-//     { }
-// }

test/libyul/yulOptimizerTests/mainFunction/smoke.yul

@@ -1,10 +0,0 @@
-{}
-// ====
-// dialect: yul
-// ----
-// step: mainFunction
-//
-// {
-//     function main()
-//     { }
-// }