From 25160bfc26cd5ae4b5104625caba41c1533614ba Mon Sep 17 00:00:00 2001 From: Alex Beregszaszi Date: Tue, 25 Oct 2016 12:38:37 +0100 Subject: Add optimiser rule for SUB with 0 --- libevmasm/ExpressionClasses.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'libevmasm/ExpressionClasses.cpp') diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp index e32b2da2..cb327252 100644 --- a/libevmasm/ExpressionClasses.cpp +++ b/libevmasm/ExpressionClasses.cpp @@ -245,17 +245,18 @@ Rules::Rules() // invariants involving known constants {{Instruction::ADD, {X, 0}}, [=]{ return X; }}, + {{Instruction::SUB, {X, 0}}, [=]{ return X; }}, {{Instruction::MUL, {X, 1}}, [=]{ return X; }}, {{Instruction::DIV, {X, 1}}, [=]{ return X; }}, {{Instruction::SDIV, {X, 1}}, [=]{ return X; }}, {{Instruction::OR, {X, 0}}, [=]{ return X; }}, {{Instruction::XOR, {X, 0}}, [=]{ return X; }}, {{Instruction::AND, {X, ~u256(0)}}, [=]{ return X; }}, + {{Instruction::AND, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::MUL, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::DIV, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::MOD, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::MOD, {0, X}}, [=]{ return u256(0); }}, - {{Instruction::AND, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::OR, {X, ~u256(0)}}, [=]{ return ~u256(0); }}, {{Instruction::EQ, {X, 0}}, [=]() -> Pattern { return {Instruction::ISZERO, {X}}; } }, // operations involving an expression and itself -- cgit v1.2.3 From b8bba6622013a6c0969392a4096a3a7384b8cf62 Mon Sep 17 00:00:00 2001 From: Alex Beregszaszi Date: Wed, 9 Nov 2016 02:22:54 +0000 Subject: Replace XOR/ISZERO with EQ --- libevmasm/ExpressionClasses.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'libevmasm/ExpressionClasses.cpp') diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp index cb327252..29fb6dbc 100644 --- a/libevmasm/ExpressionClasses.cpp +++ b/libevmasm/ExpressionClasses.cpp @@ -288,6 +288,10 @@ Rules::Rules() {Instruction::ISZERO, {{Instruction::ISZERO, {{Instruction::ISZERO, {X}}}}}}, [=]() -> Pattern { return {Instruction::ISZERO, {X}}; } }); + m_rules.push_back({ + {Instruction::ISZERO, {{Instruction::XOR, {X, Y}}}}, + [=]() -> Pattern { return { Instruction::EQ, {X, Y} }; } + }); // Associative operations for (auto const& opFun: vector>>{ {Instruction::ADD, plus()}, -- cgit v1.2.3 From 3fdef92911ea1824f7a84ce556fec48e23a314ad Mon Sep 17 00:00:00 2001 From: Alex Beregszaszi Date: Wed, 9 Nov 2016 02:25:44 +0000 Subject: Replace XOR with self with 0 --- libevmasm/ExpressionClasses.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'libevmasm/ExpressionClasses.cpp') diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp index 29fb6dbc..bb71be2e 100644 --- a/libevmasm/ExpressionClasses.cpp +++ b/libevmasm/ExpressionClasses.cpp @@ -262,6 +262,7 @@ Rules::Rules() // operations involving an expression and itself {{Instruction::AND, {X, X}}, [=]{ return X; }}, {{Instruction::OR, {X, X}}, [=]{ return X; }}, + {{Instruction::XOR, {X, X}}, [=]{ return u256(0); }}, {{Instruction::SUB, {X, X}}, [=]{ return u256(0); }}, {{Instruction::EQ, {X, X}}, [=]{ return u256(1); }}, {{Instruction::LT, {X, X}}, [=]{ return u256(0); }}, -- cgit v1.2.3 From df4b405f9c1cd3ebfd2787b5f1f6925cabf789d3 Mon Sep 17 00:00:00 2001 From: Yoichi Hirai Date: Mon, 24 Oct 2016 17:33:57 +0200 Subject: Add more optimization rules --- libevmasm/ExpressionClasses.cpp | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'libevmasm/ExpressionClasses.cpp') diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp index bb71be2e..d5ccd7e3 100644 --- a/libevmasm/ExpressionClasses.cpp +++ b/libevmasm/ExpressionClasses.cpp @@ -255,6 +255,7 @@ Rules::Rules() {{Instruction::AND, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::MUL, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::DIV, {X, 0}}, [=]{ return u256(0); }}, + {{Instruction::DIV, {0, X}}, [=]{ return u256(0); }}, {{Instruction::MOD, {X, 0}}, [=]{ return u256(0); }}, {{Instruction::MOD, {0, X}}, [=]{ return u256(0); }}, {{Instruction::OR, {X, ~u256(0)}}, [=]{ return ~u256(0); }}, @@ -272,6 +273,11 @@ Rules::Rules() {{Instruction::MOD, {X, X}}, [=]{ return u256(0); }}, {{Instruction::NOT, {{Instruction::NOT, {X}}}}, [=]{ return X; }}, + {{Instruction::XOR, {{{X}, {Instruction::XOR, {X, Y}}}}}, [=]{ return Y; }}, + {{Instruction::OR, {{{X}, {Instruction::AND, {X, Y}}}}}, [=]{ return X; }}, + {{Instruction::AND, {{{X}, {Instruction::OR, {X, Y}}}}}, [=]{ return X; }}, + {{Instruction::AND, {{{X}, {Instruction::NOT, {X}}}}}, [=]{ return u256(0); }}, + {{Instruction::OR, {{{X}, {Instruction::NOT, {X}}}}}, [=]{ return ~u256(0); }}, }; // Double negation of opcodes with binary result for (auto const& op: vector{ -- cgit v1.2.3