Support `for in` loops for `map`

src/llvm_backend_stmt.cpp

@@ -402,6 +402,22 @@ void lb_map_kvh_data_static(lbProcedure *p, lbValue map_value, lbValue *ks_, lbV
 	if (hs_) *hs_ = hs;
 }
 
+lbValue lb_map_hash_is_valid(lbProcedure *p, lbValue hash) {
+	// N :: size_of(uintptr)*8 - 1
+	// (hash != 0) & (hash>>N == 0)
+
+	u64 top_bit_index = cast(u64)(type_size_of(t_uintptr)*8 - 1);
+	lbValue shift_amount = lb_const_int(p->module, t_uintptr, top_bit_index);
+	lbValue zero = lb_const_int(p->module, t_uintptr, 0);
+
+	lbValue not_empty = lb_emit_comp(p, Token_NotEq, hash, zero);
+
+	lbValue not_deleted = lb_emit_arith(p, Token_Shr, hash, shift_amount, t_uintptr);
+	not_deleted = lb_emit_comp(p, Token_CmpEq, not_deleted, zero);
+
+	return lb_emit_arith(p, Token_And, not_deleted, not_empty, t_uintptr);
+}
+
 void lb_build_range_map(lbProcedure *p, lbValue expr, Type *val_type,
                         lbValue *val_, lbValue *key_, lbBlock **loop_, lbBlock **done_) {
 	lbModule *m = p->module;
@@ -442,19 +458,19 @@ void lb_build_range_map(lbProcedure *p, lbValue expr, Type *val_type,
 	lbValue vs = lb_map_cell_index_static(p, type->Map.key, ks, capacity);
 	lbValue hs = lb_map_cell_index_static(p, type->Map.value, vs, capacity);
 
+	// NOTE(bill): no need to use lb_map_cell_index_static for that hashes
+	// since it will always be packed without padding into the cells
 	lbValue hash = lb_emit_load(p, lb_emit_ptr_offset(p, hs, idx));
 
-	lbValue hash_cond = lb_emit_comp(p, Token_CmpEq, hash, lb_const_int(m, t_uintptr, 0));
+	lbValue hash_cond = lb_map_hash_is_valid(p, hash);
 	lb_emit_if(p, hash_cond, body, loop);
 	lb_start_block(p, body);
 
-	// lbValue entries = lb_map_entries_ptr(p, expr);
-	// lbValue elem = lb_emit_struct_ep(p, entries, 0);
-	// elem = lb_emit_load(p, elem);
-	// lbValue entry = lb_emit_ptr_offset(p, elem, idx);
-	lbValue key = lb_const_nil(m, type->Map.key);
-	lbValue val = lb_const_nil(m, type->Map.value);
 
+	lbValue key_ptr = lb_map_cell_index_static(p, type->Map.key, ks, idx);
+	lbValue val_ptr = lb_map_cell_index_static(p, type->Map.value, vs, idx);
+	lbValue key = lb_emit_load(p, key_ptr);
+	lbValue val = lb_emit_load(p, val_ptr);
 
 	if (val_)  *val_  = val;
 	if (key_)  *key_  = key;

src/llvm_backend_utility.cpp

@@ -1464,7 +1464,13 @@ lbValue lb_map_cap(lbProcedure *p, lbValue value) {
 lbValue lb_map_data_uintptr(lbProcedure *p, lbValue value) {
 	GB_ASSERT(is_type_map(value.type));
 	lbValue data = lb_emit_struct_ev(p, value, 0);
-	lbValue mask = lb_const_int(p->module, t_uintptr, MAP_CACHE_LINE_SIZE-1);
+	u64 mask_value = 0;
+	if (build_context.word_size == 4) {
+		mask_value = 0xfffffffful & ~(MAP_CACHE_LINE_SIZE-1);
+	} else {
+		mask_value = 0xffffffffffffffffull & ~(MAP_CACHE_LINE_SIZE-1);
+	}
+	lbValue mask = lb_const_int(p->module, t_uintptr, mask_value);
 	return lb_emit_arith(p, Token_And, data, mask, t_uintptr);
 }