|
| 1 | +// SPDX-License-Identifier: Apache-2.0 |
| 2 | + |
| 3 | +// smoelius: This file is a slight variant of ../polkadot.rs. |
| 4 | + |
| 5 | +use std::vec; |
| 6 | + |
| 7 | +use crate::codegen::cfg::{ControlFlowGraph, Instr}; |
| 8 | +use crate::codegen::encoding::abi_encode; |
| 9 | +use crate::codegen::events::EventEmitter; |
| 10 | +use crate::codegen::expression::expression; |
| 11 | +use crate::codegen::vartable::Vartable; |
| 12 | +use crate::codegen::{Builtin, Expression, Options}; |
| 13 | +use crate::sema::ast::{self, Function, Namespace, RetrieveType, Type}; |
| 14 | +use ink_env::hash::{CryptoHash, Keccak256}; |
| 15 | +use solang_parser::pt; |
| 16 | + |
| 17 | +/// Implements [EventEmitter] to handle the emission of events on Stylus. |
| 18 | +pub(super) struct StylusEventEmitter<'a> { |
| 19 | + /// Arguments passed to the event |
| 20 | + pub(super) args: &'a [ast::Expression], |
| 21 | + pub(super) ns: &'a Namespace, |
| 22 | + pub(super) event_no: usize, |
| 23 | +} |
| 24 | + |
| 25 | +impl EventEmitter for StylusEventEmitter<'_> { |
| 26 | + fn selector(&self, _emitting_contract_no: usize) -> Vec<u8> { |
| 27 | + let signature = self.ns.events[self.event_no].signature.as_bytes(); |
| 28 | + let mut buf = [0; 32]; |
| 29 | + <Keccak256 as CryptoHash>::hash(signature, &mut buf); |
| 30 | + buf.into() |
| 31 | + } |
| 32 | + |
| 33 | + fn emit( |
| 34 | + &self, |
| 35 | + contract_no: usize, |
| 36 | + func: &Function, |
| 37 | + cfg: &mut ControlFlowGraph, |
| 38 | + vartab: &mut Vartable, |
| 39 | + opt: &Options, |
| 40 | + ) { |
| 41 | + let loc = pt::Loc::Builtin; |
| 42 | + let event = &self.ns.events[self.event_no]; |
| 43 | + let hash_len = Box::new(Expression::NumberLiteral { |
| 44 | + loc, |
| 45 | + ty: Type::Uint(32), |
| 46 | + value: 32.into(), |
| 47 | + }); |
| 48 | + let (mut data, mut topics) = (Vec::new(), Vec::new()); |
| 49 | + |
| 50 | + // Events that are not anonymous always have themselves as a topic. |
| 51 | + // This is static and can be calculated at compile time. |
| 52 | + if !event.anonymous { |
| 53 | + topics.push(Expression::AllocDynamicBytes { |
| 54 | + loc, |
| 55 | + ty: Type::Slice(Type::Uint(8).into()), |
| 56 | + size: hash_len.clone(), |
| 57 | + initializer: self.selector(contract_no).into(), |
| 58 | + }); |
| 59 | + }; |
| 60 | + |
| 61 | + for (ast_exp, field) in self.args.iter().zip(event.fields.iter()) { |
| 62 | + let value_exp = expression(ast_exp, cfg, contract_no, Some(func), self.ns, vartab, opt); |
| 63 | + let value_var = vartab.temp_anonymous(&value_exp.ty()); |
| 64 | + let value = Expression::Variable { |
| 65 | + loc, |
| 66 | + ty: value_exp.ty(), |
| 67 | + var_no: value_var, |
| 68 | + }; |
| 69 | + cfg.add( |
| 70 | + vartab, |
| 71 | + Instr::Set { |
| 72 | + loc, |
| 73 | + res: value_var, |
| 74 | + expr: value_exp, |
| 75 | + }, |
| 76 | + ); |
| 77 | + data.push(value.clone()); |
| 78 | + |
| 79 | + if !field.indexed { |
| 80 | + continue; |
| 81 | + } |
| 82 | + |
| 83 | + let (value_encoded, size) = abi_encode(&loc, vec![value], self.ns, vartab, cfg, false); |
| 84 | + |
| 85 | + vartab.new_dirty_tracker(); |
| 86 | + let var_buffer = vartab.temp_anonymous(&Type::DynamicBytes); |
| 87 | + cfg.add( |
| 88 | + vartab, |
| 89 | + Instr::Set { |
| 90 | + loc, |
| 91 | + res: var_buffer, |
| 92 | + expr: value_encoded, |
| 93 | + }, |
| 94 | + ); |
| 95 | + let buffer = Expression::Variable { |
| 96 | + loc, |
| 97 | + ty: Type::DynamicBytes, |
| 98 | + var_no: var_buffer, |
| 99 | + }; |
| 100 | + |
| 101 | + let hash_topic_block = cfg.new_basic_block("hash_topic".into()); |
| 102 | + let done_block = cfg.new_basic_block("done".into()); |
| 103 | + let size_is_greater_than_hash_length = Expression::More { |
| 104 | + loc, |
| 105 | + signed: false, |
| 106 | + left: size.clone().into(), |
| 107 | + right: hash_len.clone(), |
| 108 | + }; |
| 109 | + cfg.add( |
| 110 | + vartab, |
| 111 | + Instr::BranchCond { |
| 112 | + cond: size_is_greater_than_hash_length, |
| 113 | + true_block: hash_topic_block, |
| 114 | + false_block: done_block, |
| 115 | + }, |
| 116 | + ); |
| 117 | + |
| 118 | + cfg.set_basic_block(hash_topic_block); |
| 119 | + cfg.add( |
| 120 | + vartab, |
| 121 | + Instr::WriteBuffer { |
| 122 | + buf: buffer.clone(), |
| 123 | + offset: Expression::NumberLiteral { |
| 124 | + loc, |
| 125 | + ty: Type::Uint(32), |
| 126 | + value: 0.into(), |
| 127 | + }, |
| 128 | + value: Expression::Builtin { |
| 129 | + loc, |
| 130 | + tys: vec![Type::Bytes(32)], |
| 131 | + kind: Builtin::Keccak256, |
| 132 | + args: vec![buffer.clone()], |
| 133 | + }, |
| 134 | + }, |
| 135 | + ); |
| 136 | + vartab.set_dirty(var_buffer); |
| 137 | + cfg.add(vartab, Instr::Branch { block: done_block }); |
| 138 | + |
| 139 | + cfg.set_basic_block(done_block); |
| 140 | + cfg.set_phis(done_block, vartab.pop_dirty_tracker()); |
| 141 | + |
| 142 | + topics.push(buffer); |
| 143 | + } |
| 144 | + |
| 145 | + let data = self |
| 146 | + .args |
| 147 | + .iter() |
| 148 | + .map(|e| expression(e, cfg, contract_no, Some(func), self.ns, vartab, opt)) |
| 149 | + .collect::<Vec<_>>(); |
| 150 | + let encoded_data = if data.is_empty() { |
| 151 | + Expression::AllocDynamicBytes { |
| 152 | + loc, |
| 153 | + ty: Type::DynamicBytes, |
| 154 | + size: Expression::NumberLiteral { |
| 155 | + loc, |
| 156 | + ty: Type::Uint(32), |
| 157 | + value: 0.into(), |
| 158 | + } |
| 159 | + .into(), |
| 160 | + initializer: Vec::new().into(), |
| 161 | + } |
| 162 | + } else { |
| 163 | + abi_encode(&loc, data, self.ns, vartab, cfg, false).0 |
| 164 | + }; |
| 165 | + |
| 166 | + cfg.add( |
| 167 | + vartab, |
| 168 | + Instr::EmitEvent { |
| 169 | + event_no: self.event_no, |
| 170 | + data: encoded_data, |
| 171 | + topics, |
| 172 | + }, |
| 173 | + ); |
| 174 | + } |
| 175 | +} |
0 commit comments