Commit a3842cbafd
Changed files (1)
src
src/AstGen.zig
@@ -5936,10 +5936,11 @@ fn switchExpr(
const operand_ty_inst = try parent_gz.addUnNode(typeof_tag, operand, operand_node);
const item_rl: ResultLoc = .{ .ty = operand_ty_inst };
- // Contains the data that goes into the `extra` array for the SwitchBlock/SwitchBlockMulti.
- // This is the header as well as the optional else prong body, as well as all the
- // scalar cases.
- // At the end we will memcpy this into place.
+ // These contain the data that goes into the `extra` array for the SwitchBlock/SwitchBlockMulti.
+ // This is the optional else prong body.
+ var special_case_payload = ArrayListUnmanaged(u32){};
+ defer special_case_payload.deinit(gpa);
+ // This is all the scalar cases.
var scalar_cases_payload = ArrayListUnmanaged(u32){};
defer scalar_cases_payload.deinit(gpa);
// Same deal, but this is only the `extra` data for the multi cases.
@@ -5957,86 +5958,10 @@ fn switchExpr(
var case_scope = parent_gz.makeSubBlock(&block_scope.base);
defer case_scope.instructions.deinit(gpa);
- // Do the else/`_` first because it goes first in the payload.
- var capture_val_scope: Scope.LocalVal = undefined;
- if (special_node != 0) {
- const case = switch (node_tags[special_node]) {
- .switch_case_one => tree.switchCaseOne(special_node),
- .switch_case => tree.switchCase(special_node),
- else => unreachable,
- };
- const sub_scope = blk: {
- const payload_token = case.payload_token orelse break :blk &case_scope.base;
- const ident = if (token_tags[payload_token] == .asterisk)
- payload_token + 1
- else
- payload_token;
- const is_ptr = ident != payload_token;
- if (mem.eql(u8, tree.tokenSlice(ident), "_")) {
- if (is_ptr) {
- return astgen.failTok(payload_token, "pointer modifier invalid on discard", .{});
- }
- break :blk &case_scope.base;
- }
- const capture_tag: Zir.Inst.Tag = if (is_ptr)
- .switch_capture_else_ref
- else
- .switch_capture_else;
- const capture = try case_scope.add(.{
- .tag = capture_tag,
- .data = .{ .switch_capture = .{
- .switch_inst = switch_block,
- .prong_index = undefined,
- } },
- });
- const capture_name = try astgen.identAsString(payload_token);
- capture_val_scope = .{
- .parent = &case_scope.base,
- .gen_zir = &case_scope,
- .name = capture_name,
- .inst = capture,
- .token_src = payload_token,
- .id_cat = .@"capture",
- };
- break :blk &capture_val_scope.base;
- };
- const case_result = try expr(&case_scope, sub_scope, block_scope.break_result_loc, case.ast.target_expr);
- try checkUsed(parent_gz, &case_scope.base, sub_scope);
- if (!parent_gz.refIsNoReturn(case_result)) {
- block_scope.break_count += 1;
- _ = try case_scope.addBreak(.@"break", switch_block, case_result);
- }
- // Documentation for this: `Zir.Inst.SwitchBlock` and `Zir.Inst.SwitchBlockMulti`.
- try scalar_cases_payload.ensureUnusedCapacity(gpa, case_scope.instructions.items.len +
- 3 + // operand, scalar_cases_len, else body len
- @boolToInt(multi_cases_len != 0));
- scalar_cases_payload.appendAssumeCapacity(@enumToInt(operand));
- scalar_cases_payload.appendAssumeCapacity(scalar_cases_len);
- if (multi_cases_len != 0) {
- scalar_cases_payload.appendAssumeCapacity(multi_cases_len);
- }
- scalar_cases_payload.appendAssumeCapacity(@intCast(u32, case_scope.instructions.items.len));
- scalar_cases_payload.appendSliceAssumeCapacity(case_scope.instructions.items);
- } else {
- // Documentation for this: `Zir.Inst.SwitchBlock` and `Zir.Inst.SwitchBlockMulti`.
- try scalar_cases_payload.ensureUnusedCapacity(
- gpa,
- @as(usize, 2) + // operand, scalar_cases_len
- @boolToInt(multi_cases_len != 0),
- );
- scalar_cases_payload.appendAssumeCapacity(@enumToInt(operand));
- scalar_cases_payload.appendAssumeCapacity(scalar_cases_len);
- if (multi_cases_len != 0) {
- scalar_cases_payload.appendAssumeCapacity(multi_cases_len);
- }
- }
-
- // In this pass we generate all the item and prong expressions except the special case.
+ // In this pass we generate all the item and prong expressions.
var multi_case_index: u32 = 0;
var scalar_case_index: u32 = 0;
for (case_nodes) |case_node| {
- if (case_node == special_node)
- continue;
const case = switch (node_tags[case_node]) {
.switch_case_one => tree.switchCaseOne(case_node),
.switch_case => tree.switchCase(case_node),
@@ -6046,9 +5971,10 @@ fn switchExpr(
// Reset the scope.
case_scope.instructions.shrinkRetainingCapacity(0);
- const is_multi_case = case.ast.values.len != 1 or
- node_tags[case.ast.values[0]] == .switch_range;
+ const is_multi_case = case.ast.values.len > 1 or
+ (case.ast.values.len == 1 and node_tags[case.ast.values[0]] == .switch_range);
+ var capture_val_scope: Scope.LocalVal = undefined;
const sub_scope = blk: {
const payload_token = case.payload_token orelse break :blk &case_scope.base;
const ident = if (token_tags[payload_token] == .asterisk)
@@ -6062,28 +5988,42 @@ fn switchExpr(
}
break :blk &case_scope.base;
}
- const is_multi_case_bits: u2 = @boolToInt(is_multi_case);
- const is_ptr_bits: u2 = @boolToInt(is_ptr);
- const capture_tag: Zir.Inst.Tag = switch ((is_multi_case_bits << 1) | is_ptr_bits) {
- 0b00 => .switch_capture,
- 0b01 => .switch_capture_ref,
- 0b10 => .switch_capture_multi,
- 0b11 => .switch_capture_multi_ref,
- };
- const capture_index = if (is_multi_case) ci: {
- multi_case_index += 1;
- break :ci multi_case_index - 1;
- } else ci: {
- scalar_case_index += 1;
- break :ci scalar_case_index - 1;
+ const capture = if (case_node == special_node) capture: {
+ const capture_tag: Zir.Inst.Tag = if (is_ptr)
+ .switch_capture_else_ref
+ else
+ .switch_capture_else;
+ break :capture try case_scope.add(.{
+ .tag = capture_tag,
+ .data = .{ .switch_capture = .{
+ .switch_inst = switch_block,
+ .prong_index = undefined,
+ } },
+ });
+ } else capture: {
+ const is_multi_case_bits: u2 = @boolToInt(is_multi_case);
+ const is_ptr_bits: u2 = @boolToInt(is_ptr);
+ const capture_tag: Zir.Inst.Tag = switch ((is_multi_case_bits << 1) | is_ptr_bits) {
+ 0b00 => .switch_capture,
+ 0b01 => .switch_capture_ref,
+ 0b10 => .switch_capture_multi,
+ 0b11 => .switch_capture_multi_ref,
+ };
+ const capture_index = if (is_multi_case) ci: {
+ multi_case_index += 1;
+ break :ci multi_case_index - 1;
+ } else ci: {
+ scalar_case_index += 1;
+ break :ci scalar_case_index - 1;
+ };
+ break :capture try case_scope.add(.{
+ .tag = capture_tag,
+ .data = .{ .switch_capture = .{
+ .switch_inst = switch_block,
+ .prong_index = capture_index,
+ } },
+ });
};
- const capture = try case_scope.add(.{
- .tag = capture_tag,
- .data = .{ .switch_capture = .{
- .switch_inst = switch_block,
- .prong_index = capture_index,
- } },
- });
const capture_name = try astgen.identAsString(ident);
capture_val_scope = .{
.parent = &case_scope.base,
@@ -6135,6 +6075,17 @@ fn switchExpr(
multi_cases_payload.items[header_index + 1] = ranges_len;
multi_cases_payload.items[header_index + 2] = @intCast(u32, case_scope.instructions.items.len);
try multi_cases_payload.appendSlice(gpa, case_scope.instructions.items);
+ } else if (case_node == special_node) {
+ const case_result = try expr(&case_scope, sub_scope, block_scope.break_result_loc, case.ast.target_expr);
+ try checkUsed(parent_gz, &case_scope.base, sub_scope);
+ if (!parent_gz.refIsNoReturn(case_result)) {
+ block_scope.break_count += 1;
+ _ = try case_scope.addBreak(.@"break", switch_block, case_result);
+ }
+ try special_case_payload.ensureUnusedCapacity(gpa, 1 + // body_len
+ case_scope.instructions.items.len);
+ special_case_payload.appendAssumeCapacity(@intCast(u32, case_scope.instructions.items.len));
+ special_case_payload.appendSliceAssumeCapacity(case_scope.instructions.items);
} else {
const item_node = case.ast.values[0];
const item_inst = try comptimeExpr(parent_gz, scope, item_rl, item_node);
@@ -6144,7 +6095,7 @@ fn switchExpr(
block_scope.break_count += 1;
_ = try case_scope.addBreak(.@"break", switch_block, case_result);
}
- try scalar_cases_payload.ensureUnusedCapacity(gpa, 2 +
+ try scalar_cases_payload.ensureUnusedCapacity(gpa, 2 + // item + body_len
case_scope.instructions.items.len);
scalar_cases_payload.appendAssumeCapacity(@enumToInt(item_inst));
scalar_cases_payload.appendAssumeCapacity(@intCast(u32, case_scope.instructions.items.len));
@@ -6181,8 +6132,18 @@ fn switchExpr(
const payload_index = astgen.extra.items.len;
const zir_datas = astgen.instructions.items(.data);
zir_datas[switch_block].pl_node.payload_index = @intCast(u32, payload_index);
- try astgen.extra.ensureUnusedCapacity(gpa, scalar_cases_payload.items.len +
+ // Documentation for this: `Zir.Inst.SwitchBlock` and `Zir.Inst.SwitchBlockMulti`.
+ try astgen.extra.ensureUnusedCapacity(gpa,
+ @as(usize, 2) + // operand, scalar_cases_len
+ @boolToInt(multi_cases_len != 0) +
+ special_case_payload.items.len +
+ scalar_cases_payload.items.len +
multi_cases_payload.items.len);
+ astgen.extra.appendAssumeCapacity(@enumToInt(operand));
+ astgen.extra.appendAssumeCapacity(scalar_cases_len);
+ if (multi_cases_len != 0) {
+ astgen.extra.appendAssumeCapacity(multi_cases_len);
+ }
const strat = rl.strategy(&block_scope);
switch (strat.tag) {
.break_operand => {
@@ -6190,6 +6151,7 @@ fn switchExpr(
// `elide_store_to_block_ptr_instructions` will either be true,
// or all prongs are noreturn.
if (!strat.elide_store_to_block_ptr_instructions) {
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items);
astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items);
astgen.extra.appendSliceAssumeCapacity(multi_cases_payload.items);
return indexToRef(switch_block);
@@ -6205,32 +6167,30 @@ fn switchExpr(
// it as the break operand.
var extra_index: usize = 0;
- extra_index += 2;
- extra_index += @boolToInt(multi_cases_len != 0);
if (special_prong != .none) special_prong: {
const body_len_index = extra_index;
- const body_len = scalar_cases_payload.items[extra_index];
+ const body_len = special_case_payload.items[extra_index];
extra_index += 1;
if (body_len < 2) {
extra_index += body_len;
- astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items[0..extra_index]);
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items[0..extra_index]);
break :special_prong;
}
extra_index += body_len - 2;
- const store_inst = scalar_cases_payload.items[extra_index];
+ const store_inst = special_case_payload.items[extra_index];
if (zir_tags[store_inst] != .store_to_block_ptr or
zir_datas[store_inst].bin.lhs != block_scope.rl_ptr)
{
extra_index += 2;
- astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items[0..extra_index]);
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items[0..extra_index]);
break :special_prong;
}
assert(zir_datas[store_inst].bin.lhs == block_scope.rl_ptr);
if (block_scope.rl_ty_inst != .none) {
extra_index += 1;
- const break_inst = scalar_cases_payload.items[extra_index];
+ const break_inst = special_case_payload.items[extra_index];
extra_index += 1;
- astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items[0..extra_index]);
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items[0..extra_index]);
zir_tags[store_inst] = .as;
zir_datas[store_inst].bin = .{
.lhs = block_scope.rl_ty_inst,
@@ -6238,15 +6198,16 @@ fn switchExpr(
};
zir_datas[break_inst].@"break".operand = indexToRef(store_inst);
} else {
- scalar_cases_payload.items[body_len_index] -= 1;
- astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items[0..extra_index]);
+ special_case_payload.items[body_len_index] -= 1;
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items[0..extra_index]);
extra_index += 1;
- astgen.extra.appendAssumeCapacity(scalar_cases_payload.items[extra_index]);
+ astgen.extra.appendAssumeCapacity(special_case_payload.items[extra_index]);
extra_index += 1;
}
} else {
- astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items[0..extra_index]);
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items[0..extra_index]);
}
+ extra_index = 0;
var scalar_i: u32 = 0;
while (scalar_i < scalar_cases_len) : (scalar_i += 1) {
const start_index = extra_index;
@@ -6343,6 +6304,7 @@ fn switchExpr(
},
.break_void => {
assert(!strat.elide_store_to_block_ptr_instructions);
+ astgen.extra.appendSliceAssumeCapacity(special_case_payload.items);
astgen.extra.appendSliceAssumeCapacity(scalar_cases_payload.items);
astgen.extra.appendSliceAssumeCapacity(multi_cases_payload.items);
// Modify all the terminating instruction tags to become `break` variants.