diff --git a/bins/revm-test/src/bin/analysis.rs b/bins/revm-test/src/bin/analysis.rs index 49fdbc57a7..b8557b6926 100644 --- a/bins/revm-test/src/bin/analysis.rs +++ b/bins/revm-test/src/bin/analysis.rs @@ -25,7 +25,7 @@ fn main() { .with_db(BenchmarkDB::new_bytecode(bytecode_raw)) .build(); - // just to spead up processor. + // Just to warm up the processor. for _ in 0..10000 { let _ = evm.transact().unwrap(); } diff --git a/crates/interpreter/src/instructions/bitwise.rs b/crates/interpreter/src/instructions/bitwise.rs index 3f49dc57eb..d832964214 100644 --- a/crates/interpreter/src/instructions/bitwise.rs +++ b/crates/interpreter/src/instructions/bitwise.rs @@ -5,6 +5,7 @@ use crate::{ Host, Interpreter, }; use core::cmp::Ordering; +use revm_primitives::uint; pub fn lt(interpreter: &mut Interpreter, _host: &mut H) { gas!(interpreter, gas::VERYLOW); @@ -103,7 +104,11 @@ pub fn sar(interpreter: &mut Interpreter, _host: &mut H) { let value_sign = i256_sign_compl(op2); - *op2 = if value_sign == Sign::Zero || op1 >= U256::from(256) { + // If the shift count is 255+, we can short-circuit. This is because shifting by 255 bits is the + // maximum shift that still leaves 1 bit in the original 256-bit number. Shifting by 256 bits or + // more would mean that no original bits remain. The result depends on what the highest bit of + // the value is. + *op2 = if value_sign == Sign::Zero || op1 >= U256::from(255) { match value_sign { // value is 0 or >=1, pushing 0 Sign::Plus | Sign::Zero => U256::ZERO, @@ -111,7 +116,8 @@ pub fn sar(interpreter: &mut Interpreter, _host: &mut H) { Sign::Minus => U256::MAX, } } else { - const ONE: U256 = U256::from_limbs([1, 0, 0, 0]); + const ONE: U256 = uint!(1_U256); + // SAFETY: shift count is checked above; it's less than 255. let shift = usize::try_from(op1).unwrap(); match value_sign { Sign::Plus | Sign::Zero => op2.wrapping_shr(shift), @@ -119,3 +125,278 @@ pub fn sar(interpreter: &mut Interpreter, _host: &mut H) { } }; } + +#[cfg(test)] +mod tests { + use crate::instructions::bitwise::{sar, shl, shr}; + use crate::{Contract, DummyHost, Interpreter}; + use revm_primitives::{uint, Env, LatestSpec, U256}; + + #[test] + fn test_shift_left() { + let mut host = DummyHost::new(Env::default()); + let mut interpreter = Interpreter::new(Contract::default(), u64::MAX, false); + + struct TestCase { + value: U256, + shift: U256, + expected: U256, + } + + uint! { + let test_cases = [ + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x00_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000002_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0xff_U256, + expected: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x0100_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x0101_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x00_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x01_U256, + expected: 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xff_U256, + expected: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x0100_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x01_U256, + expected: 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe_U256, + }, + ]; + } + + for test in test_cases { + host.clear(); + push!(interpreter, test.value); + push!(interpreter, test.shift); + shl::(&mut interpreter, &mut host); + pop!(interpreter, res); + assert_eq!(res, test.expected); + } + } + + #[test] + fn test_logical_shift_right() { + let mut host = DummyHost::new(Env::default()); + let mut interpreter = Interpreter::new(Contract::default(), u64::MAX, false); + + struct TestCase { + value: U256, + shift: U256, + expected: U256, + } + + uint! { + let test_cases = [ + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x00_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x01_U256, + expected: 0x4000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0xff_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x0100_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x0101_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x00_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x01_U256, + expected: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xff_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x0100_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + ]; + } + + for test in test_cases { + host.clear(); + push!(interpreter, test.value); + push!(interpreter, test.shift); + shr::(&mut interpreter, &mut host); + pop!(interpreter, res); + assert_eq!(res, test.expected); + } + } + + #[test] + fn test_arithmetic_shift_right() { + let mut host = DummyHost::new(Env::default()); + let mut interpreter = Interpreter::new(Contract::default(), u64::MAX, false); + + struct TestCase { + value: U256, + shift: U256, + expected: U256, + } + + uint! { + let test_cases = [ + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x00_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x01_U256, + expected: 0xc000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0xff_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x0100_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0x8000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x0101_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x00_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x01_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xff_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x0100_U256, + expected: 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + }, + TestCase { + value: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0x01_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x4000000000000000000000000000000000000000000000000000000000000000_U256, + shift: 0xfe_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xf8_U256, + expected: 0x000000000000000000000000000000000000000000000000000000000000007f_U256, + }, + TestCase { + value: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xfe_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000001_U256, + }, + TestCase { + value: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0xff_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + TestCase { + value: 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff_U256, + shift: 0x0100_U256, + expected: 0x0000000000000000000000000000000000000000000000000000000000000000_U256, + }, + ]; + } + + for test in test_cases { + host.clear(); + push!(interpreter, test.value); + push!(interpreter, test.shift); + sar::(&mut interpreter, &mut host); + pop!(interpreter, res); + assert_eq!(res, test.expected); + } + } +}