diff options
Diffstat (limited to 'src/mir/from_hir_match.cpp')
| -rw-r--r-- | src/mir/from_hir_match.cpp | 52 |
1 files changed, 46 insertions, 6 deletions
diff --git a/src/mir/from_hir_match.cpp b/src/mir/from_hir_match.cpp index 058bf2ab..d1a93b0f 100644 --- a/src/mir/from_hir_match.cpp +++ b/src/mir/from_hir_match.cpp @@ -13,6 +13,7 @@ void MIR_LowerHIR_Match( MirBuilder& builder, MirConverter& conv, ::HIR::ExprNode_Match& node, ::MIR::LValue match_val ); #define FIELD_DEREF 255 +#define FIELD_INDEX_MAX 128 struct field_path_t { @@ -1374,6 +1375,7 @@ void PatternRulesetBuilder::append_from(const Span& sp, const ::HIR::Pattern& pa PatternRulesetBuilder sub_builder { this->m_resolve }; sub_builder.m_field_path = m_field_path; sub_builder.m_field_path.push_back(0); + ASSERT_BUG(sp, pe.sub_patterns.size() < FIELD_INDEX_MAX, "Too many slice rules to fit encodng"); for(const auto& subpat : pe.sub_patterns) { sub_builder.append_from( sp, subpat, *e.inner ); @@ -1386,6 +1388,7 @@ void PatternRulesetBuilder::append_from(const Span& sp, const ::HIR::Pattern& pa (SplitSlice, PatternRulesetBuilder sub_builder { this->m_resolve }; sub_builder.m_field_path = m_field_path; + ASSERT_BUG(sp, pe.leading.size() < FIELD_INDEX_MAX, "Too many leading slice rules to fit encodng"); sub_builder.m_field_path.push_back(0); for(const auto& subpat : pe.leading) { @@ -1394,11 +1397,17 @@ void PatternRulesetBuilder::append_from(const Span& sp, const ::HIR::Pattern& pa } auto leading = mv$(sub_builder.m_rules); - sub_builder.m_field_path.back() = 0; if( pe.trailing.size() ) { // Needs a way of encoding the negative offset in the field path - TODO(sp, "SplitSlice on [T] with trailing - " << pat); + // - For now, just use a very high number (and assert that it's not more than 128) + ASSERT_BUG(sp, pe.trailing.size() < FIELD_INDEX_MAX, "Too many trailing slice rules to fit encodng"); + sub_builder.m_field_path.back() = FIELD_INDEX_MAX + (FIELD_INDEX_MAX - pe.trailing.size()); + for(const auto& subpat : pe.trailing) + { + sub_builder.append_from( sp, subpat, *e.inner ); + sub_builder.m_field_path.back() ++; + } } auto trailing = mv$(sub_builder.m_rules); @@ -1838,11 +1847,32 @@ namespace { (Array, assert(idx < e.size_val); cur_ty = &*e.inner; - lval = ::MIR::LValue::make_Field({ box$(lval), idx }); + if( idx < FIELD_INDEX_MAX ) + lval = ::MIR::LValue::make_Field({ box$(lval), idx }); + else { + idx -= FIELD_INDEX_MAX; + idx = FIELD_INDEX_MAX - idx; + TODO(sp, "Index " << idx << " from end of array " << lval); + } ), (Slice, cur_ty = &*e.inner; - lval = ::MIR::LValue::make_Field({ box$(lval), idx }); + if( idx < FIELD_INDEX_MAX ) + lval = ::MIR::LValue::make_Field({ box$(lval), idx }); + else { + idx -= FIELD_INDEX_MAX; + idx = FIELD_INDEX_MAX - idx; + TODO(sp, "Index " << idx << " from end of slice " << lval); + // 1. Create an LValue containing the size of this slice subtract `idx` + // TODO: Requires access to the MIR generator +#if 0 + auto len_lval = m_builder.lvalue_or_temp(sp, ::HIR::CoreType::Usize, ::MIR::RValue::make_DstMeta({ m_builder.get_ptr_to_dst(sp, lval).clone() })); + auto sub_val = ::MIR::Param(::MIR::Constant::make_Uint({ idx, ::HIR::CoreType::Usize })); + auto ofs_val = m_builder.lvalue_or_temp(sp, ::HIR::CoreType::Usize, ::MIR::RValue::make_BinOp({ mv$(len_lval), ::MIR::eBinOp::SUB, mv$(sub_val) }) ); + // Return _Index with that value + lval = ::MIR::LValue::make_Index({ box$(lval), box$(ofs_val) }); +#endif + } ), (Borrow, ASSERT_BUG(sp, idx == FIELD_DEREF, "Destructure of borrow doesn't correspond to a deref in the path"); @@ -2506,7 +2536,10 @@ namespace { for(auto& sr : leading) push_flat_rules(out_rules, mv$(sr)); // TODO: the trailing rules need a special path format. - ASSERT_BUG(Span(), trailing.size() == 0, "TODO: Handle SplitSlice with trailing"); + if( !e.trailing.empty() ) + { + TODO(Span(), "Handle SplitSlice with trailing"); + } for(auto& sr : trailing) push_flat_rules(out_rules, mv$(sr)); ), @@ -3290,9 +3323,16 @@ void MatchGenGrouped::gen_dispatch_splitslice(const field_path_t& field_path, co m_builder.set_cur_block(next); } + // 3. Recurse into trailing patterns if( e.trailing_len != 0 ) { - TODO(sp, "Handle trailing rules in SplitSlice - " << e.trailing); + auto next = m_builder.new_bb_unlinked(); + auto inner_set = t_rules_subset { 1, /*is_arm_indexes=*/false }; + inner_set.push_bb( e.trailing, next ); + auto inst = MatchGenGrouped { m_builder, sp, ty, val, {}, field_path.size() }; + inst.gen_for_slice(inner_set, 0, def_blk); + + m_builder.set_cur_block(next); } } |