aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--libevmasm/RuleList.h11
1 files changed, 11 insertions, 0 deletions
diff --git a/libevmasm/RuleList.h b/libevmasm/RuleList.h
index 2312d673..da522cec 100644
--- a/libevmasm/RuleList.h
+++ b/libevmasm/RuleList.h
@@ -153,6 +153,17 @@ std::vector<SimplificationRule<Pattern>> simplificationRuleList(
{{Instruction::OR, {{Instruction::NOT, {X}}, X}}, [=]{ return ~u256(0); }, true},
};
+ // Replace MOD X, <power-of-two> with AND X, <power-of-two> - 1
+ for (size_t i = 0; i < 256; ++i)
+ {
+ u256 value = u256(1) << i;
+ rules.push_back({
+ {Instruction::MOD, {X, value}},
+ [=]() -> Pattern { return {Instruction::AND, {X, value - 1}}; },
+ false
+ });
+ }
+
// Double negation of opcodes with boolean result
for (auto const& op: std::vector<Instruction>{
Instruction::EQ,