diff options
| -rw-r--r-- | src/mir/from_hir.hpp | 10 | ||||
| -rw-r--r-- | src/mir/mir_builder.cpp | 141 |
2 files changed, 105 insertions, 46 deletions
diff --git a/src/mir/from_hir.hpp b/src/mir/from_hir.hpp index c33ba274..0dfc9e50 100644 --- a/src/mir/from_hir.hpp +++ b/src/mir/from_hir.hpp @@ -91,9 +91,11 @@ TAGGED_UNION(ScopeType, Variables, ::std::vector<SplitArm> arms; }), (Loop, struct { - ::std::set<unsigned int> changed_vars; - ::std::set<unsigned int> changed_tmps; - ::std::vector<SplitArm> exit_states; + // NOTE: This contains the original state for variables changed after `exit_state_valid` is true + ::std::map<unsigned int,VarState> changed_vars; + ::std::map<unsigned int,VarState> changed_tmps; + bool exit_state_valid; + SplitEnd exit_state; }) ); @@ -225,6 +227,8 @@ private: const VarState& get_temp_state(const Span& sp, unsigned int idx, unsigned int skip_count=0) const; VarState& get_temp_state_mut(const Span& sp, unsigned int idx); + void terminate_loop_early(const Span& sp, ScopeType::Data_Loop& sd_loop); + void drop_value_from_state(const Span& sp, const VarState& vs, ::MIR::LValue lv); void drop_scope_values(const ScopeDef& sd); void complete_scope(ScopeDef& sd); diff --git a/src/mir/mir_builder.cpp b/src/mir/mir_builder.cpp index 62f8e9c3..197d2518 100644 --- a/src/mir/mir_builder.cpp +++ b/src/mir/mir_builder.cpp @@ -625,6 +625,7 @@ void MirBuilder::terminate_scope(const Span& sp, ScopeHandle scope, bool emit_cl complete_scope(scope_def); } + void MirBuilder::terminate_scope_early(const Span& sp, const ScopeHandle& scope, bool loop_exit/*=false*/) { TRACE_FUNCTION_F("EARLY scope " << scope.idx); @@ -647,17 +648,7 @@ void MirBuilder::terminate_scope_early(const Span& sp, const ScopeHandle& scope, // If this is exiting a loop, save the state so the variable state after the loop is known. if( loop_exit && scope_def.data.is_Loop() ) { - auto& e = scope_def.data.as_Loop(); - SplitArm sa; - for(const auto& i : e.changed_vars) - { - sa.var_states.insert( ::std::make_pair(i, get_variable_state(sp, i).clone()) ); - } - for(const auto& i : e.changed_tmps) - { - sa.tmp_states.insert( ::std::make_pair(i, get_temp_state(sp, i).clone()) ); - } - e.exit_states.push_back( mv$(sa) ); + terminate_loop_early(sp, scope_def.data.as_Loop()); } } @@ -900,6 +891,48 @@ namespace } } +void MirBuilder::terminate_loop_early(const Span& sp, ScopeType::Data_Loop& sd_loop) +{ + if( sd_loop.exit_state_valid ) + { + // Insert copies of parent state for newly changed values + // and Merge all changed values + for(const auto& ent : sd_loop.changed_vars) + { + auto idx = ent.first; + if( sd_loop.exit_state.var_states.count(idx) == 0 ) { + sd_loop.exit_state.var_states.insert(::std::make_pair( idx, ent.second.clone() )); + } + auto& old_state = sd_loop.exit_state.var_states.at(idx); + merge_state(sp, *this, ::MIR::LValue::make_Variable(idx), old_state, get_variable_state(sp, idx)); + } + for(const auto& ent : sd_loop.changed_tmps) + { + auto idx = ent.first; + if( sd_loop.exit_state.tmp_states.count(idx) == 0 ) { + sd_loop.exit_state.tmp_states.insert(::std::make_pair( idx, ent.second.clone() )); + } + auto& old_state = sd_loop.exit_state.tmp_states.at(idx); + merge_state(sp, *this, ::MIR::LValue::make_Temporary({idx}), old_state, get_temp_state(sp, idx)); + } + } + else + { + // Obtain states of changed variables/temporaries + for(const auto& ent : sd_loop.changed_vars) + { + auto idx = ent.first; + sd_loop.exit_state.var_states.insert(::std::make_pair( idx, get_variable_state(sp, idx).clone() )); + } + for(const auto& ent : sd_loop.changed_tmps) + { + auto idx = ent.first; + sd_loop.exit_state.tmp_states.insert(::std::make_pair( idx, get_temp_state(sp, idx).clone() )); + } + sd_loop.exit_state_valid = true; + } +} + void MirBuilder::end_split_arm(const Span& sp, const ScopeHandle& handle, bool reachable) { ASSERT_BUG(sp, handle.idx < m_scopes.size(), ""); @@ -955,6 +988,10 @@ void MirBuilder::end_split_arm(const Span& sp, const ScopeHandle& handle, bool r merge_state(sp, *this, ::MIR::LValue::make_Temporary({idx}), out_state, src_state); } } + else + { + DEBUG("Unreachable, not merging"); + } } else { @@ -986,14 +1023,17 @@ void MirBuilder::end_split_arm_early(const Span& sp) complete_scope(scope_def); } - if( !m_scope_stack.empty() && m_scopes.at( m_scope_stack.back() ).data.is_Split() ) + if( !m_scope_stack.empty() ) { - DEBUG("Early terminate split scope " << m_scope_stack.back()); - auto& sd = m_scopes[ m_scope_stack.back() ]; - auto& sd_split = sd.data.as_Split(); - sd_split.arms.back().has_early_terminated = true; + if( m_scopes.at( m_scope_stack.back() ).data.is_Split() ) + { + DEBUG("Early terminate split scope " << m_scope_stack.back()); + auto& sd = m_scopes[ m_scope_stack.back() ]; + auto& sd_split = sd.data.as_Split(); + sd_split.arms.back().has_early_terminated = true; - // TODO: Create drop flags if required? + // TODO: Create drop flags if required? + } } } void MirBuilder::complete_scope(ScopeDef& sd) @@ -1013,16 +1053,40 @@ void MirBuilder::complete_scope(ScopeDef& sd) (Split, ) ) + + struct H { + static void apply_end_state(const Span& sp, MirBuilder& builder, SplitEnd& end_state) + { + for(auto& ent : end_state.var_states) + { + auto& vs = builder.get_variable_state_mut(sp, ent.first); + if( vs != ent.second ) + { + DEBUG(::MIR::LValue::make_Variable(ent.first) << " " << vs << " => " << ent.second); + vs = ::std::move(ent.second); + } + } + for(auto& ent : end_state.tmp_states) + { + auto& vs = builder.get_temp_state_mut(sp, ent.first); + if( vs != ent.second ) + { + DEBUG(::MIR::LValue::make_Temporary({ent.first}) << " " << vs << " => " << ent.second); + vs = ::std::move(ent.second); + } + } + } + }; + // No macro for better debug output. if( sd.data.is_Loop() ) { - #if 0 auto& e = sd.data.as_Loop(); - TRACE_FUNCTION_F("Loop - " << e.exit_states.size() << " breaks"); - - // Merge all exit states and apply to output - H::apply_split_arms(*this, sd.span, e.exit_states); - #endif + TRACE_FUNCTION_F("Loop"); + if( e.exit_state_valid ) + { + H::apply_end_state(sd.span, *this, e.exit_state); + } } else if( sd.data.is_Split() ) { @@ -1030,24 +1094,7 @@ void MirBuilder::complete_scope(ScopeDef& sd) TRACE_FUNCTION_F("Split - " << (e.arms.size() - 1) << " arms"); ASSERT_BUG(sd.span, e.end_state_valid, ""); - for(auto& ent : e.end_state.var_states) - { - auto& vs = get_variable_state_mut(sd.span, ent.first); - if( vs != ent.second ) - { - DEBUG(::MIR::LValue::make_Variable(ent.first) << " " << vs << " => " << ent.second); - vs = ::std::move(ent.second); - } - } - for(auto& ent : e.end_state.tmp_states) - { - auto& vs = get_temp_state_mut(sd.span, ent.first); - if( vs != ent.second ) - { - DEBUG(::MIR::LValue::make_Temporary({ent.first}) << " " << vs << " => " << ent.second); - vs = ::std::move(ent.second); - } - } + H::apply_end_state(sd.span, *this, e.end_state); } } @@ -1291,7 +1338,11 @@ VarState& MirBuilder::get_variable_state_mut(const Span& sp, unsigned int idx) else if( scope_def.data.is_Loop() ) { auto& e = scope_def.data.as_Loop(); - e.changed_vars.insert( idx ); + if( e.changed_vars.count(idx) == 0 ) + { + auto state = e.exit_state_valid ? get_variable_state(sp, idx).clone() : VarState::make_Valid({}); + e.changed_vars.insert(::std::make_pair( idx, mv$(state) )); + } } else { @@ -1357,7 +1408,11 @@ VarState& MirBuilder::get_temp_state_mut(const Span& sp, unsigned int idx) else if( scope_def.data.is_Loop() ) { auto& e = scope_def.data.as_Loop(); - e.changed_tmps.insert( idx ); + if( e.changed_tmps.count(idx) == 0 ) + { + auto state = e.exit_state_valid ? get_temp_state(sp, idx).clone() : VarState::make_Valid({}); + e.changed_tmps.insert(::std::make_pair( idx, mv$(state) )); + } } else { |