mirror of
https://github.com/ziglang/zig.git
synced 2026-01-11 09:55:12 +00:00
astgen.zig: make switchExpr generate cases in source order to keep source cursor increasing monotonically
This commit is contained in:
Matthew Borkowski
parent
a1c802cbba
commit
a3842cbafd
198
src/AstGen.zig
198
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 = 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_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 = 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.
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user