Commit 121d995fcb061272202649a964f4788a3c9c8305 | zig

author	Meghan Denny <hello@nektro.net> 2023-11-24 17:09:08-08:00
committer	Meghan Denny <hello@nektro.net> 2023-11-24 17:09:08-08:00
log	121d995fcb061272202649a964f4788a3c9c8305
tree	197f5ff8d36fef30457a3566e6791719be723c29
parent	84d58aaa1fc8508cb6ec9a455e8127ff13f17e16

frontend: move AstRlAnnotate to std.zig namespace

4 files changed, 1107 insertions(+), 1106 deletions(-)

lib
- std
  - zig.zig
  - zig
    AstRlAnnotate.zig
src
- AstGen.zig
- AstRlAnnotate.zig

lib/std/zig.zig+1

...	@@ -18,6 +18,7 @@ pub const Ast = @import("zig/Ast.zig");	...	@@ -18,6 +18,7 @@ pub const Ast = @import("zig/Ast.zig");
18	pub const system = @import("zig/system.zig");	18	pub const system = @import("zig/system.zig");
19	pub const CrossTarget = @import("zig/CrossTarget.zig");	19	pub const CrossTarget = @import("zig/CrossTarget.zig");
20	pub const BuiltinFn = @import("zig/BuiltinFn.zig");	20	pub const BuiltinFn = @import("zig/BuiltinFn.zig");
		21	pub const AstRlAnnotate = @import("zig/AstRlAnnotate.zig");
21		22
22	// Character literal parsing	23	// Character literal parsing
23	pub const ParsedCharLiteral = string_literal.ParsedCharLiteral;	24	pub const ParsedCharLiteral = string_literal.ParsedCharLiteral;

lib/std/zig/AstRlAnnotate.zig created+1105

...	@@ -0,0 +1,1105 @@
1	//! AstRlAnnotate is a simple pass which runs over the AST before AstGen to
2	//! determine which expressions require result locations.
3	//!
4	//! In some cases, AstGen can choose whether to provide a result pointer or to
5	//! just use standard `break` instructions from a block. The latter choice can
6	//! result in more efficient ZIR and runtime code, but does not allow for RLS to
7	//! occur. Thus, we want to provide a real result pointer (from an alloc) only
8	//! when necessary.
9	//!
10	//! To achive this, we need to determine which expressions require a result
11	//! pointer. This pass is reponsible for analyzing all syntax forms which may
12	//! provide a result location and, if sub-expressions consume this result
13	//! pointer non-trivially (e.g. writing through field pointers), marking the
14	//! node as requiring a result location.
15
16	const std = @import("std");
17	const AstRlAnnotate = @This();
18	const Ast = std.zig.Ast;
19	const Allocator = std.mem.Allocator;
20	const AutoHashMapUnmanaged = std.AutoHashMapUnmanaged;
21	const BuiltinFn = std.zig.BuiltinFn;
22	const assert = std.debug.assert;
23
24	gpa: Allocator,
25	arena: Allocator,
26	tree: *const Ast,
27
28	/// Certain nodes are placed in this set under the following conditions:
29	/// * if-else: either branch consumes the result location
30	/// * labeled block: any break consumes the result location
31	/// * switch: any prong consumes the result location
32	/// * orelse/catch: the RHS expression consumes the result location
33	/// * while/for: any break consumes the result location
34	/// * @as: the second operand consumes the result location
35	/// * const: the init expression consumes the result location
36	/// * return: the return expression consumes the result location
37	nodes_need_rl: RlNeededSet = .{},
38
39	pub const RlNeededSet = AutoHashMapUnmanaged(Ast.Node.Index, void);
40
41	const ResultInfo = packed struct {
42	/// Do we have a known result type?
43	have_type: bool,
44	/// Do we (potentially) have a result pointer? Note that this pointer's type
45	/// may not be known due to it being an inferred alloc.
46	have_ptr: bool,
47
48	const none: ResultInfo = .{ .have_type = false, .have_ptr = false };
49	const typed_ptr: ResultInfo = .{ .have_type = true, .have_ptr = true };
50	const inferred_ptr: ResultInfo = .{ .have_type = false, .have_ptr = true };
51	const type_only: ResultInfo = .{ .have_type = true, .have_ptr = false };
52	};
53
54	/// A labeled block or a loop. When this block is broken from, `consumes_res_ptr`
55	/// should be set if the break expression consumed the result pointer.
56	const Block = struct {
57	parent: ?*Block,
58	label: ?[]const u8,
59	is_loop: bool,
60	ri: ResultInfo,
61	consumes_res_ptr: bool,
62	};
63
64	pub fn annotate(gpa: Allocator, arena: Allocator, tree: Ast) Allocator.Error!RlNeededSet {
65	var astrl: AstRlAnnotate = .{
66	.gpa = gpa,
67	.arena = arena,
68	.tree = &tree,
69	};
70	defer astrl.deinit(gpa);
71
72	if (tree.errors.len != 0) {
73	// We can't perform analysis on a broken AST. AstGen will not run in
74	// this case.
75	return .{};
76	}
77
78	for (tree.containerDeclRoot().ast.members) \|member_node\| {
79	_ = try astrl.expr(member_node, null, ResultInfo.none);
80	}
81
82	return astrl.nodes_need_rl.move();
83	}
84
85	fn deinit(astrl: *AstRlAnnotate, gpa: Allocator) void {
86	astrl.nodes_need_rl.deinit(gpa);
87	}
88
89	fn containerDecl(
90	astrl: *AstRlAnnotate,
91	block: ?*Block,
92	full: Ast.full.ContainerDecl,
93	) !void {
94	const tree = astrl.tree;
95	const token_tags = tree.tokens.items(.tag);
96	switch (token_tags[full.ast.main_token]) {
97	.keyword_struct => {
98	if (full.ast.arg != 0) {
99	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
100	}
101	for (full.ast.members) \|member_node\| {
102	_ = try astrl.expr(member_node, block, ResultInfo.none);
103	}
104	},
105	.keyword_union => {
106	if (full.ast.arg != 0) {
107	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
108	}
109	for (full.ast.members) \|member_node\| {
110	_ = try astrl.expr(member_node, block, ResultInfo.none);
111	}
112	},
113	.keyword_enum => {
114	if (full.ast.arg != 0) {
115	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
116	}
117	for (full.ast.members) \|member_node\| {
118	_ = try astrl.expr(member_node, block, ResultInfo.none);
119	}
120	},
121	.keyword_opaque => {
122	for (full.ast.members) \|member_node\| {
123	_ = try astrl.expr(member_node, block, ResultInfo.none);
124	}
125	},
126	else => unreachable,
127	}
128	}
129
130	/// Returns true if `rl` provides a result pointer and the expression consumes it.
131	fn expr(astrl: AstRlAnnotate, node: Ast.Node.Index, block: ?Block, ri: ResultInfo) Allocator.Error!bool {
132	const tree = astrl.tree;
133	const token_tags = tree.tokens.items(.tag);
134	const node_datas = tree.nodes.items(.data);
135	const node_tags = tree.nodes.items(.tag);
136	switch (node_tags[node]) {
137	.root,
138	.switch_case_one,
139	.switch_case_inline_one,
140	.switch_case,
141	.switch_case_inline,
142	.switch_range,
143	.for_range,
144	.asm_output,
145	.asm_input,
146	=> unreachable,
147
148	.@"errdefer", .@"defer" => {
149	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
150	return false;
151	},
152
153	.container_field_init,
154	.container_field_align,
155	.container_field,
156	=> {
157	const full = tree.fullContainerField(node).?;
158	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.type_only);
159	if (full.ast.align_expr != 0) {
160	_ = try astrl.expr(full.ast.align_expr, block, ResultInfo.type_only);
161	}
162	if (full.ast.value_expr != 0) {
163	_ = try astrl.expr(full.ast.value_expr, block, ResultInfo.type_only);
164	}
165	return false;
166	},
167	.@"usingnamespace" => {
168	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
169	return false;
170	},
171	.test_decl => {
172	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
173	return false;
174	},
175	.global_var_decl,
176	.local_var_decl,
177	.simple_var_decl,
178	.aligned_var_decl,
179	=> {
180	const full = tree.fullVarDecl(node).?;
181	const init_ri = if (full.ast.type_node != 0) init_ri: {
182	_ = try astrl.expr(full.ast.type_node, block, ResultInfo.type_only);
183	break :init_ri ResultInfo.typed_ptr;
184	} else ResultInfo.inferred_ptr;
185	if (full.ast.init_node == 0) {
186	// No init node, so we're done.
187	return false;
188	}
189	switch (token_tags[full.ast.mut_token]) {
190	.keyword_const => {
191	const init_consumes_rl = try astrl.expr(full.ast.init_node, block, init_ri);
192	if (init_consumes_rl) {
193	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
194	}
195	return false;
196	},
197	.keyword_var => {
198	// We'll create an alloc either way, so don't care if the
199	// result pointer is consumed.
200	_ = try astrl.expr(full.ast.init_node, block, init_ri);
201	return false;
202	},
203	else => unreachable,
204	}
205	},
206	.assign_destructure => {
207	const lhs_count = tree.extra_data[node_datas[node].lhs];
208	const all_lhs = tree.extra_data[node_datas[node].lhs + 1 ..][0..lhs_count];
209	for (all_lhs) \|lhs\| {
210	_ = try astrl.expr(lhs, block, ResultInfo.none);
211	}
212	// We don't need to gather any meaningful data here, because destructures always use RLS
213	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
214	return false;
215	},
216	.assign => {
217	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
218	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.typed_ptr);
219	return false;
220	},
221	.assign_shl,
222	.assign_shl_sat,
223	.assign_shr,
224	.assign_bit_and,
225	.assign_bit_or,
226	.assign_bit_xor,
227	.assign_div,
228	.assign_sub,
229	.assign_sub_wrap,
230	.assign_sub_sat,
231	.assign_mod,
232	.assign_add,
233	.assign_add_wrap,
234	.assign_add_sat,
235	.assign_mul,
236	.assign_mul_wrap,
237	.assign_mul_sat,
238	=> {
239	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
240	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
241	return false;
242	},
243	.shl, .shr => {
244	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
245	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
246	return false;
247	},
248	.add,
249	.add_wrap,
250	.add_sat,
251	.sub,
252	.sub_wrap,
253	.sub_sat,
254	.mul,
255	.mul_wrap,
256	.mul_sat,
257	.div,
258	.mod,
259	.shl_sat,
260	.bit_and,
261	.bit_or,
262	.bit_xor,
263	.bang_equal,
264	.equal_equal,
265	.greater_than,
266	.greater_or_equal,
267	.less_than,
268	.less_or_equal,
269	.array_cat,
270	=> {
271	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
272	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
273	return false;
274	},
275	.array_mult => {
276	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
277	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
278	return false;
279	},
280	.error_union, .merge_error_sets => {
281	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
282	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
283	return false;
284	},
285	.bool_and,
286	.bool_or,
287	=> {
288	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
289	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
290	return false;
291	},
292	.bool_not => {
293	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
294	return false;
295	},
296	.bit_not, .negation, .negation_wrap => {
297	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
298	return false;
299	},
300
301	// These nodes are leaves and never consume a result location.
302	.identifier,
303	.string_literal,
304	.multiline_string_literal,
305	.number_literal,
306	.unreachable_literal,
307	.asm_simple,
308	.@"asm",
309	.enum_literal,
310	.error_value,
311	.anyframe_literal,
312	.@"continue",
313	.char_literal,
314	.error_set_decl,
315	=> return false,
316
317	.builtin_call_two, .builtin_call_two_comma => {
318	if (node_datas[node].lhs == 0) {
319	return astrl.builtinCall(block, ri, node, &.{});
320	} else if (node_datas[node].rhs == 0) {
321	return astrl.builtinCall(block, ri, node, &.{node_datas[node].lhs});
322	} else {
323	return astrl.builtinCall(block, ri, node, &.{ node_datas[node].lhs, node_datas[node].rhs });
324	}
325	},
326	.builtin_call, .builtin_call_comma => {
327	const params = tree.extra_data[node_datas[node].lhs..node_datas[node].rhs];
328	return astrl.builtinCall(block, ri, node, params);
329	},
330
331	.call_one,
332	.call_one_comma,
333	.async_call_one,
334	.async_call_one_comma,
335	.call,
336	.call_comma,
337	.async_call,
338	.async_call_comma,
339	=> {
340	var buf: [1]Ast.Node.Index = undefined;
341	const full = tree.fullCall(&buf, node).?;
342	_ = try astrl.expr(full.ast.fn_expr, block, ResultInfo.none);
343	for (full.ast.params) \|param_node\| {
344	_ = try astrl.expr(param_node, block, ResultInfo.type_only);
345	}
346	return switch (node_tags[node]) {
347	.call_one,
348	.call_one_comma,
349	.call,
350	.call_comma,
351	=> false, // TODO: once function calls are passed result locations this will change
352	.async_call_one,
353	.async_call_one_comma,
354	.async_call,
355	.async_call_comma,
356	=> ri.have_ptr, // always use result ptr for frames
357	else => unreachable,
358	};
359	},
360
361	.@"return" => {
362	if (node_datas[node].lhs != 0) {
363	const ret_val_consumes_rl = try astrl.expr(node_datas[node].lhs, block, ResultInfo.typed_ptr);
364	if (ret_val_consumes_rl) {
365	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
366	}
367	}
368	return false;
369	},
370
371	.field_access => {
372	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
373	return false;
374	},
375
376	.if_simple, .@"if" => {
377	const full = tree.fullIf(node).?;
378	if (full.error_token != null or full.payload_token != null) {
379	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.none);
380	} else {
381	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.type_only); // bool
382	}
383
384	if (full.ast.else_expr == 0) {
385	_ = try astrl.expr(full.ast.then_expr, block, ResultInfo.none);
386	return false;
387	} else {
388	const then_uses_rl = try astrl.expr(full.ast.then_expr, block, ri);
389	const else_uses_rl = try astrl.expr(full.ast.else_expr, block, ri);
390	const uses_rl = then_uses_rl or else_uses_rl;
391	if (uses_rl) try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
392	return uses_rl;
393	}
394	},
395
396	.while_simple, .while_cont, .@"while" => {
397	const full = tree.fullWhile(node).?;
398	const label: ?[]const u8 = if (full.label_token) \|label_token\| label: {
399	break :label try astrl.identString(label_token);
400	} else null;
401	if (full.error_token != null or full.payload_token != null) {
402	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.none);
403	} else {
404	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.type_only); // bool
405	}
406	var new_block: Block = .{
407	.parent = block,
408	.label = label,
409	.is_loop = true,
410	.ri = ri,
411	.consumes_res_ptr = false,
412	};
413	if (full.ast.cont_expr != 0) {
414	_ = try astrl.expr(full.ast.cont_expr, &new_block, ResultInfo.none);
415	}
416	_ = try astrl.expr(full.ast.then_expr, &new_block, ResultInfo.none);
417	const else_consumes_rl = if (full.ast.else_expr != 0) else_rl: {
418	break :else_rl try astrl.expr(full.ast.else_expr, block, ri);
419	} else false;
420	if (new_block.consumes_res_ptr or else_consumes_rl) {
421	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
422	return true;
423	} else {
424	return false;
425	}
426	},
427
428	.for_simple, .@"for" => {
429	const full = tree.fullFor(node).?;
430	const label: ?[]const u8 = if (full.label_token) \|label_token\| label: {
431	break :label try astrl.identString(label_token);
432	} else null;
433	for (full.ast.inputs) \|input\| {
434	if (node_tags[input] == .for_range) {
435	_ = try astrl.expr(node_datas[input].lhs, block, ResultInfo.type_only);
436	if (node_datas[input].rhs != 0) {
437	_ = try astrl.expr(node_datas[input].rhs, block, ResultInfo.type_only);
438	}
439	} else {
440	_ = try astrl.expr(input, block, ResultInfo.none);
441	}
442	}
443	var new_block: Block = .{
444	.parent = block,
445	.label = label,
446	.is_loop = true,
447	.ri = ri,
448	.consumes_res_ptr = false,
449	};
450	_ = try astrl.expr(full.ast.then_expr, &new_block, ResultInfo.none);
451	const else_consumes_rl = if (full.ast.else_expr != 0) else_rl: {
452	break :else_rl try astrl.expr(full.ast.else_expr, block, ri);
453	} else false;
454	if (new_block.consumes_res_ptr or else_consumes_rl) {
455	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
456	return true;
457	} else {
458	return false;
459	}
460	},
461
462	.slice_open => {
463	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
464	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
465	return false;
466	},
467	.slice => {
468	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.Slice);
469	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
470	_ = try astrl.expr(extra.start, block, ResultInfo.type_only);
471	_ = try astrl.expr(extra.end, block, ResultInfo.type_only);
472	return false;
473	},
474	.slice_sentinel => {
475	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SliceSentinel);
476	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
477	_ = try astrl.expr(extra.start, block, ResultInfo.type_only);
478	if (extra.end != 0) {
479	_ = try astrl.expr(extra.end, block, ResultInfo.type_only);
480	}
481	_ = try astrl.expr(extra.sentinel, block, ResultInfo.none);
482	return false;
483	},
484	.deref => {
485	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
486	return false;
487	},
488	.address_of => {
489	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
490	return false;
491	},
492	.optional_type => {
493	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
494	return false;
495	},
496	.grouped_expression,
497	.@"try",
498	.@"await",
499	.@"nosuspend",
500	.unwrap_optional,
501	=> return astrl.expr(node_datas[node].lhs, block, ri),
502
503	.block_two, .block_two_semicolon => {
504	if (node_datas[node].lhs == 0) {
505	return astrl.blockExpr(block, ri, node, &.{});
506	} else if (node_datas[node].rhs == 0) {
507	return astrl.blockExpr(block, ri, node, &.{node_datas[node].lhs});
508	} else {
509	return astrl.blockExpr(block, ri, node, &.{ node_datas[node].lhs, node_datas[node].rhs });
510	}
511	},
512	.block, .block_semicolon => {
513	const statements = tree.extra_data[node_datas[node].lhs..node_datas[node].rhs];
514	return astrl.blockExpr(block, ri, node, statements);
515	},
516	.anyframe_type => {
517	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
518	return false;
519	},
520	.@"catch", .@"orelse" => {
521	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
522	const rhs_consumes_rl = try astrl.expr(node_datas[node].rhs, block, ri);
523	if (rhs_consumes_rl) {
524	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
525	}
526	return rhs_consumes_rl;
527	},
528
529	.ptr_type_aligned,
530	.ptr_type_sentinel,
531	.ptr_type,
532	.ptr_type_bit_range,
533	=> {
534	const full = tree.fullPtrType(node).?;
535	_ = try astrl.expr(full.ast.child_type, block, ResultInfo.type_only);
536	if (full.ast.sentinel != 0) {
537	_ = try astrl.expr(full.ast.sentinel, block, ResultInfo.type_only);
538	}
539	if (full.ast.addrspace_node != 0) {
540	_ = try astrl.expr(full.ast.addrspace_node, block, ResultInfo.type_only);
541	}
542	if (full.ast.align_node != 0) {
543	_ = try astrl.expr(full.ast.align_node, block, ResultInfo.type_only);
544	}
545	if (full.ast.bit_range_start != 0) {
546	assert(full.ast.bit_range_end != 0);
547	_ = try astrl.expr(full.ast.bit_range_start, block, ResultInfo.type_only);
548	_ = try astrl.expr(full.ast.bit_range_end, block, ResultInfo.type_only);
549	}
550	return false;
551	},
552
553	.container_decl,
554	.container_decl_trailing,
555	.container_decl_arg,
556	.container_decl_arg_trailing,
557	.container_decl_two,
558	.container_decl_two_trailing,
559	.tagged_union,
560	.tagged_union_trailing,
561	.tagged_union_enum_tag,
562	.tagged_union_enum_tag_trailing,
563	.tagged_union_two,
564	.tagged_union_two_trailing,
565	=> {
566	var buf: [2]Ast.Node.Index = undefined;
567	try astrl.containerDecl(block, tree.fullContainerDecl(&buf, node).?);
568	return false;
569	},
570
571	.@"break" => {
572	if (node_datas[node].rhs == 0) {
573	// Breaks with void are not interesting
574	return false;
575	}
576
577	var opt_cur_block = block;
578	if (node_datas[node].lhs == 0) {
579	// No label - we're breaking from a loop.
580	while (opt_cur_block) \|cur_block\| : (opt_cur_block = cur_block.parent) {
581	if (cur_block.is_loop) break;
582	}
583	} else {
584	const break_label = try astrl.identString(node_datas[node].lhs);
585	while (opt_cur_block) \|cur_block\| : (opt_cur_block = cur_block.parent) {
586	const block_label = cur_block.label orelse continue;
587	if (std.mem.eql(u8, block_label, break_label)) break;
588	}
589	}
590
591	if (opt_cur_block) \|target_block\| {
592	const consumes_break_rl = try astrl.expr(node_datas[node].rhs, block, target_block.ri);
593	if (consumes_break_rl) target_block.consumes_res_ptr = true;
594	} else {
595	// No corresponding scope to break from - AstGen will emit an error.
596	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
597	}
598
599	return false;
600	},
601
602	.array_type => {
603	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
604	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
605	return false;
606	},
607	.array_type_sentinel => {
608	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.ArrayTypeSentinel);
609	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
610	_ = try astrl.expr(extra.elem_type, block, ResultInfo.type_only);
611	_ = try astrl.expr(extra.sentinel, block, ResultInfo.type_only);
612	return false;
613	},
614	.array_access => {
615	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
616	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
617	return false;
618	},
619	.@"comptime" => {
620	// AstGen will emit an error if the scope is already comptime, so we can assume it is
621	// not. This means the result location is not forwarded.
622	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
623	return false;
624	},
625	.@"switch", .switch_comma => {
626	const operand_node = node_datas[node].lhs;
627	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SubRange);
628	const case_nodes = tree.extra_data[extra.start..extra.end];
629
630	_ = try astrl.expr(operand_node, block, ResultInfo.none);
631
632	var any_prong_consumed_rl = false;
633	for (case_nodes) \|case_node\| {
634	const case = tree.fullSwitchCase(case_node).?;
635	for (case.ast.values) \|item_node\| {
636	if (node_tags[item_node] == .switch_range) {
637	_ = try astrl.expr(node_datas[item_node].lhs, block, ResultInfo.none);
638	_ = try astrl.expr(node_datas[item_node].rhs, block, ResultInfo.none);
639	} else {
640	_ = try astrl.expr(item_node, block, ResultInfo.none);
641	}
642	}
643	if (try astrl.expr(case.ast.target_expr, block, ri)) {
644	any_prong_consumed_rl = true;
645	}
646	}
647	if (any_prong_consumed_rl) {
648	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
649	}
650	return any_prong_consumed_rl;
651	},
652	.@"suspend" => {
653	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
654	return false;
655	},
656	.@"resume" => {
657	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
658	return false;
659	},
660
661	.array_init_one,
662	.array_init_one_comma,
663	.array_init_dot_two,
664	.array_init_dot_two_comma,
665	.array_init_dot,
666	.array_init_dot_comma,
667	.array_init,
668	.array_init_comma,
669	=> {
670	var buf: [2]Ast.Node.Index = undefined;
671	const full = tree.fullArrayInit(&buf, node).?;
672
673	if (full.ast.type_expr != 0) {
674	// Explicitly typed init does not participate in RLS
675	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.none);
676	for (full.ast.elements) \|elem_init\| {
677	_ = try astrl.expr(elem_init, block, ResultInfo.type_only);
678	}
679	return false;
680	}
681
682	if (ri.have_type) {
683	// Always forward type information
684	// If we have a result pointer, we use and forward it
685	for (full.ast.elements) \|elem_init\| {
686	_ = try astrl.expr(elem_init, block, ri);
687	}
688	return ri.have_ptr;
689	} else {
690	// Untyped init does not consume result location
691	for (full.ast.elements) \|elem_init\| {
692	_ = try astrl.expr(elem_init, block, ResultInfo.none);
693	}
694	return false;
695	}
696	},
697
698	.struct_init_one,
699	.struct_init_one_comma,
700	.struct_init_dot_two,
701	.struct_init_dot_two_comma,
702	.struct_init_dot,
703	.struct_init_dot_comma,
704	.struct_init,
705	.struct_init_comma,
706	=> {
707	var buf: [2]Ast.Node.Index = undefined;
708	const full = tree.fullStructInit(&buf, node).?;
709
710	if (full.ast.type_expr != 0) {
711	// Explicitly typed init does not participate in RLS
712	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.none);
713	for (full.ast.fields) \|field_init\| {
714	_ = try astrl.expr(field_init, block, ResultInfo.type_only);
715	}
716	return false;
717	}
718
719	if (ri.have_type) {
720	// Always forward type information
721	// If we have a result pointer, we use and forward it
722	for (full.ast.fields) \|field_init\| {
723	_ = try astrl.expr(field_init, block, ri);
724	}
725	return ri.have_ptr;
726	} else {
727	// Untyped init does not consume result location
728	for (full.ast.fields) \|field_init\| {
729	_ = try astrl.expr(field_init, block, ResultInfo.none);
730	}
731	return false;
732	}
733	},
734
735	.fn_proto_simple,
736	.fn_proto_multi,
737	.fn_proto_one,
738	.fn_proto,
739	.fn_decl,
740	=> {
741	var buf: [1]Ast.Node.Index = undefined;
742	const full = tree.fullFnProto(&buf, node).?;
743	const body_node = if (node_tags[node] == .fn_decl) node_datas[node].rhs else 0;
744	{
745	var it = full.iterate(tree);
746	while (it.next()) \|param\| {
747	if (param.anytype_ellipsis3 == null) {
748	_ = try astrl.expr(param.type_expr, block, ResultInfo.type_only);
749	}
750	}
751	}
752	if (full.ast.align_expr != 0) {
753	_ = try astrl.expr(full.ast.align_expr, block, ResultInfo.type_only);
754	}
755	if (full.ast.addrspace_expr != 0) {
756	_ = try astrl.expr(full.ast.addrspace_expr, block, ResultInfo.type_only);
757	}
758	if (full.ast.section_expr != 0) {
759	_ = try astrl.expr(full.ast.section_expr, block, ResultInfo.type_only);
760	}
761	if (full.ast.callconv_expr != 0) {
762	_ = try astrl.expr(full.ast.callconv_expr, block, ResultInfo.type_only);
763	}
764	_ = try astrl.expr(full.ast.return_type, block, ResultInfo.type_only);
765	if (body_node != 0) {
766	_ = try astrl.expr(body_node, block, ResultInfo.none);
767	}
768	return false;
769	},
770	}
771	}
772
773	fn identString(astrl: *AstRlAnnotate, token: Ast.TokenIndex) ![]const u8 {
774	const tree = astrl.tree;
775	const token_tags = tree.tokens.items(.tag);
776	assert(token_tags[token] == .identifier);
777	const ident_name = tree.tokenSlice(token);
778	if (!std.mem.startsWith(u8, ident_name, "@")) {
779	return ident_name;
780	}
781	return std.zig.string_literal.parseAlloc(astrl.arena, ident_name[1..]) catch \|err\| switch (err) {
782	error.OutOfMemory => error.OutOfMemory,
783	error.InvalidLiteral => "", // This pass can safely return garbage on invalid AST
784	};
785	}
786
787	fn blockExpr(astrl: AstRlAnnotate, parent_block: ?Block, ri: ResultInfo, node: Ast.Node.Index, statements: []const Ast.Node.Index) !bool {
788	const tree = astrl.tree;
789	const token_tags = tree.tokens.items(.tag);
790	const main_tokens = tree.nodes.items(.main_token);
791
792	const lbrace = main_tokens[node];
793	if (token_tags[lbrace - 1] == .colon and
794	token_tags[lbrace - 2] == .identifier)
795	{
796	// Labeled block
797	var new_block: Block = .{
798	.parent = parent_block,
799	.label = try astrl.identString(lbrace - 2),
800	.is_loop = false,
801	.ri = ri,
802	.consumes_res_ptr = false,
803	};
804	for (statements) \|statement\| {
805	_ = try astrl.expr(statement, &new_block, ResultInfo.none);
806	}
807	if (new_block.consumes_res_ptr) {
808	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
809	}
810	return new_block.consumes_res_ptr;
811	} else {
812	// Unlabeled block
813	for (statements) \|statement\| {
814	_ = try astrl.expr(statement, parent_block, ResultInfo.none);
815	}
816	return false;
817	}
818	}
819
820	fn builtinCall(astrl: AstRlAnnotate, block: ?Block, ri: ResultInfo, node: Ast.Node.Index, args: []const Ast.Node.Index) !bool {
821	_ = ri; // Currently, no builtin consumes its result location.
822
823	const tree = astrl.tree;
824	const main_tokens = tree.nodes.items(.main_token);
825	const builtin_token = main_tokens[node];
826	const builtin_name = tree.tokenSlice(builtin_token);
827	const info = BuiltinFn.list.get(builtin_name) orelse return false;
828	if (info.param_count) \|expected\| {
829	if (expected != args.len) return false;
830	}
831	switch (info.tag) {
832	.import => return false,
833	.compile_log, .TypeOf => {
834	for (args) \|arg_node\| {
835	_ = try astrl.expr(arg_node, block, ResultInfo.none);
836	}
837	return false;
838	},
839	.as => {
840	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
841	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
842	return false;
843	},
844	.bit_cast => {
845	_ = try astrl.expr(args[0], block, ResultInfo.none);
846	return false;
847	},
848	.union_init => {
849	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
850	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
851	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
852	return false;
853	},
854	.c_import => {
855	_ = try astrl.expr(args[0], block, ResultInfo.none);
856	return false;
857	},
858	.min, .max => {
859	for (args) \|arg_node\| {
860	_ = try astrl.expr(arg_node, block, ResultInfo.none);
861	}
862	return false;
863	},
864	.@"export" => {
865	_ = try astrl.expr(args[0], block, ResultInfo.none);
866	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
867	return false;
868	},
869	.@"extern" => {
870	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
871	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
872	return false;
873	},
874	// These builtins take no args and do not consume the result pointer.
875	.src,
876	.This,
877	.return_address,
878	.error_return_trace,
879	.frame,
880	.breakpoint,
881	.in_comptime,
882	.panic,
883	.trap,
884	.c_va_start,
885	=> return false,
886	// TODO: this is a workaround for llvm/llvm-project#68409
887	// Zig tracking issue: #16876
888	.frame_address => return true,
889	// These builtins take a single argument with a known result type, but do not consume their
890	// result pointer.
891	.size_of,
892	.bit_size_of,
893	.align_of,
894	.compile_error,
895	.set_eval_branch_quota,
896	.int_from_bool,
897	.int_from_error,
898	.error_from_int,
899	.embed_file,
900	.error_name,
901	.set_runtime_safety,
902	.Type,
903	.c_undef,
904	.c_include,
905	.wasm_memory_size,
906	.splat,
907	.fence,
908	.set_float_mode,
909	.set_align_stack,
910	.set_cold,
911	.type_info,
912	.work_item_id,
913	.work_group_size,
914	.work_group_id,
915	=> {
916	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
917	return false;
918	},
919	// These builtins take a single argument with no result information and do not consume their
920	// result pointer.
921	.int_from_ptr,
922	.int_from_enum,
923	.sqrt,
924	.sin,
925	.cos,
926	.tan,
927	.exp,
928	.exp2,
929	.log,
930	.log2,
931	.log10,
932	.abs,
933	.floor,
934	.ceil,
935	.trunc,
936	.round,
937	.tag_name,
938	.type_name,
939	.Frame,
940	.frame_size,
941	.int_from_float,
942	.float_from_int,
943	.ptr_from_int,
944	.enum_from_int,
945	.float_cast,
946	.int_cast,
947	.truncate,
948	.error_cast,
949	.ptr_cast,
950	.align_cast,
951	.addrspace_cast,
952	.const_cast,
953	.volatile_cast,
954	.clz,
955	.ctz,
956	.pop_count,
957	.byte_swap,
958	.bit_reverse,
959	=> {
960	_ = try astrl.expr(args[0], block, ResultInfo.none);
961	return false;
962	},
963	.div_exact,
964	.div_floor,
965	.div_trunc,
966	.mod,
967	.rem,
968	=> {
969	_ = try astrl.expr(args[0], block, ResultInfo.none);
970	_ = try astrl.expr(args[1], block, ResultInfo.none);
971	return false;
972	},
973	.shl_exact, .shr_exact => {
974	_ = try astrl.expr(args[0], block, ResultInfo.none);
975	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
976	return false;
977	},
978	.bit_offset_of,
979	.offset_of,
980	.field_parent_ptr,
981	.has_decl,
982	.has_field,
983	.field,
984	=> {
985	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
986	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
987	return false;
988	},
989	.wasm_memory_grow => {
990	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
991	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
992	return false;
993	},
994	.c_define => {
995	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
996	_ = try astrl.expr(args[1], block, ResultInfo.none);
997	return false;
998	},
999	.reduce => {
1000	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1001	_ = try astrl.expr(args[1], block, ResultInfo.none);
1002	return false;
1003	},
1004	.add_with_overflow, .sub_with_overflow, .mul_with_overflow, .shl_with_overflow => {
1005	_ = try astrl.expr(args[0], block, ResultInfo.none);
1006	_ = try astrl.expr(args[1], block, ResultInfo.none);
1007	return false;
1008	},
1009	.atomic_load => {
1010	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1011	_ = try astrl.expr(args[1], block, ResultInfo.none);
1012	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1013	return false;
1014	},
1015	.atomic_rmw => {
1016	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1017	_ = try astrl.expr(args[1], block, ResultInfo.none);
1018	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1019	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1020	_ = try astrl.expr(args[4], block, ResultInfo.type_only);
1021	return false;
1022	},
1023	.atomic_store => {
1024	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1025	_ = try astrl.expr(args[1], block, ResultInfo.none);
1026	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1027	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1028	return false;
1029	},
1030	.mul_add => {
1031	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1032	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1033	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1034	return false;
1035	},
1036	.call => {
1037	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1038	_ = try astrl.expr(args[1], block, ResultInfo.none);
1039	_ = try astrl.expr(args[2], block, ResultInfo.none);
1040	return false;
1041	},
1042	.memcpy => {
1043	_ = try astrl.expr(args[0], block, ResultInfo.none);
1044	_ = try astrl.expr(args[1], block, ResultInfo.none);
1045	return false;
1046	},
1047	.memset => {
1048	_ = try astrl.expr(args[0], block, ResultInfo.none);
1049	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1050	return false;
1051	},
1052	.shuffle => {
1053	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1054	_ = try astrl.expr(args[1], block, ResultInfo.none);
1055	_ = try astrl.expr(args[2], block, ResultInfo.none);
1056	_ = try astrl.expr(args[3], block, ResultInfo.none);
1057	return false;
1058	},
1059	.select => {
1060	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1061	_ = try astrl.expr(args[1], block, ResultInfo.none);
1062	_ = try astrl.expr(args[2], block, ResultInfo.none);
1063	_ = try astrl.expr(args[3], block, ResultInfo.none);
1064	return false;
1065	},
1066	.async_call => {
1067	_ = try astrl.expr(args[0], block, ResultInfo.none);
1068	_ = try astrl.expr(args[1], block, ResultInfo.none);
1069	_ = try astrl.expr(args[2], block, ResultInfo.none);
1070	_ = try astrl.expr(args[3], block, ResultInfo.none);
1071	return false; // buffer passed as arg for frame data
1072	},
1073	.Vector => {
1074	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1075	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1076	return false;
1077	},
1078	.prefetch => {
1079	_ = try astrl.expr(args[0], block, ResultInfo.none);
1080	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1081	return false;
1082	},
1083	.c_va_arg => {
1084	_ = try astrl.expr(args[0], block, ResultInfo.none);
1085	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1086	return false;
1087	},
1088	.c_va_copy => {
1089	_ = try astrl.expr(args[0], block, ResultInfo.none);
1090	return false;
1091	},
1092	.c_va_end => {
1093	_ = try astrl.expr(args[0], block, ResultInfo.none);
1094	return false;
1095	},
1096	.cmpxchg_strong, .cmpxchg_weak => {
1097	_ = try astrl.expr(args[0], block, ResultInfo.none);
1098	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1099	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1100	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1101	_ = try astrl.expr(args[4], block, ResultInfo.type_only);
1102	return false;
1103	},
1104	}
1105	}

src/AstGen.zig+1-1

...	@@ -14,7 +14,7 @@ const isPrimitive = std.zig.primitives.isPrimitive;	...	@@ -14,7 +14,7 @@ const isPrimitive = std.zig.primitives.isPrimitive;
14		14
15	const Zir = @import("Zir.zig");	15	const Zir = @import("Zir.zig");
16	const BuiltinFn = std.zig.BuiltinFn;	16	const BuiltinFn = std.zig.BuiltinFn;
17	const AstRlAnnotate = @import("AstRlAnnotate.zig");	17	const AstRlAnnotate = std.zig.AstRlAnnotate;
18		18
19	gpa: Allocator,	19	gpa: Allocator,
20	tree: *const Ast,	20	tree: *const Ast,

src/AstRlAnnotate.zig deleted-1105

...	@@ -1,1105 +0,0 @@
1	//! AstRlAnnotate is a simple pass which runs over the AST before AstGen to
2	//! determine which expressions require result locations.
3	//!
4	//! In some cases, AstGen can choose whether to provide a result pointer or to
5	//! just use standard `break` instructions from a block. The latter choice can
6	//! result in more efficient ZIR and runtime code, but does not allow for RLS to
7	//! occur. Thus, we want to provide a real result pointer (from an alloc) only
8	//! when necessary.
9	//!
10	//! To achive this, we need to determine which expressions require a result
11	//! pointer. This pass is reponsible for analyzing all syntax forms which may
12	//! provide a result location and, if sub-expressions consume this result
13	//! pointer non-trivially (e.g. writing through field pointers), marking the
14	//! node as requiring a result location.
15
16	const std = @import("std");
17	const AstRlAnnotate = @This();
18	const Ast = std.zig.Ast;
19	const Allocator = std.mem.Allocator;
20	const AutoHashMapUnmanaged = std.AutoHashMapUnmanaged;
21	const BuiltinFn = std.zig.BuiltinFn;
22	const assert = std.debug.assert;
23
24	gpa: Allocator,
25	arena: Allocator,
26	tree: *const Ast,
27
28	/// Certain nodes are placed in this set under the following conditions:
29	/// * if-else: either branch consumes the result location
30	/// * labeled block: any break consumes the result location
31	/// * switch: any prong consumes the result location
32	/// * orelse/catch: the RHS expression consumes the result location
33	/// * while/for: any break consumes the result location
34	/// * @as: the second operand consumes the result location
35	/// * const: the init expression consumes the result location
36	/// * return: the return expression consumes the result location
37	nodes_need_rl: RlNeededSet = .{},
38
39	pub const RlNeededSet = AutoHashMapUnmanaged(Ast.Node.Index, void);
40
41	const ResultInfo = packed struct {
42	/// Do we have a known result type?
43	have_type: bool,
44	/// Do we (potentially) have a result pointer? Note that this pointer's type
45	/// may not be known due to it being an inferred alloc.
46	have_ptr: bool,
47
48	const none: ResultInfo = .{ .have_type = false, .have_ptr = false };
49	const typed_ptr: ResultInfo = .{ .have_type = true, .have_ptr = true };
50	const inferred_ptr: ResultInfo = .{ .have_type = false, .have_ptr = true };
51	const type_only: ResultInfo = .{ .have_type = true, .have_ptr = false };
52	};
53
54	/// A labeled block or a loop. When this block is broken from, `consumes_res_ptr`
55	/// should be set if the break expression consumed the result pointer.
56	const Block = struct {
57	parent: ?*Block,
58	label: ?[]const u8,
59	is_loop: bool,
60	ri: ResultInfo,
61	consumes_res_ptr: bool,
62	};
63
64	pub fn annotate(gpa: Allocator, arena: Allocator, tree: Ast) Allocator.Error!RlNeededSet {
65	var astrl: AstRlAnnotate = .{
66	.gpa = gpa,
67	.arena = arena,
68	.tree = &tree,
69	};
70	defer astrl.deinit(gpa);
71
72	if (tree.errors.len != 0) {
73	// We can't perform analysis on a broken AST. AstGen will not run in
74	// this case.
75	return .{};
76	}
77
78	for (tree.containerDeclRoot().ast.members) \|member_node\| {
79	_ = try astrl.expr(member_node, null, ResultInfo.none);
80	}
81
82	return astrl.nodes_need_rl.move();
83	}
84
85	fn deinit(astrl: *AstRlAnnotate, gpa: Allocator) void {
86	astrl.nodes_need_rl.deinit(gpa);
87	}
88
89	fn containerDecl(
90	astrl: *AstRlAnnotate,
91	block: ?*Block,
92	full: Ast.full.ContainerDecl,
93	) !void {
94	const tree = astrl.tree;
95	const token_tags = tree.tokens.items(.tag);
96	switch (token_tags[full.ast.main_token]) {
97	.keyword_struct => {
98	if (full.ast.arg != 0) {
99	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
100	}
101	for (full.ast.members) \|member_node\| {
102	_ = try astrl.expr(member_node, block, ResultInfo.none);
103	}
104	},
105	.keyword_union => {
106	if (full.ast.arg != 0) {
107	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
108	}
109	for (full.ast.members) \|member_node\| {
110	_ = try astrl.expr(member_node, block, ResultInfo.none);
111	}
112	},
113	.keyword_enum => {
114	if (full.ast.arg != 0) {
115	_ = try astrl.expr(full.ast.arg, block, ResultInfo.type_only);
116	}
117	for (full.ast.members) \|member_node\| {
118	_ = try astrl.expr(member_node, block, ResultInfo.none);
119	}
120	},
121	.keyword_opaque => {
122	for (full.ast.members) \|member_node\| {
123	_ = try astrl.expr(member_node, block, ResultInfo.none);
124	}
125	},
126	else => unreachable,
127	}
128	}
129
130	/// Returns true if `rl` provides a result pointer and the expression consumes it.
131	fn expr(astrl: AstRlAnnotate, node: Ast.Node.Index, block: ?Block, ri: ResultInfo) Allocator.Error!bool {
132	const tree = astrl.tree;
133	const token_tags = tree.tokens.items(.tag);
134	const node_datas = tree.nodes.items(.data);
135	const node_tags = tree.nodes.items(.tag);
136	switch (node_tags[node]) {
137	.root,
138	.switch_case_one,
139	.switch_case_inline_one,
140	.switch_case,
141	.switch_case_inline,
142	.switch_range,
143	.for_range,
144	.asm_output,
145	.asm_input,
146	=> unreachable,
147
148	.@"errdefer", .@"defer" => {
149	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
150	return false;
151	},
152
153	.container_field_init,
154	.container_field_align,
155	.container_field,
156	=> {
157	const full = tree.fullContainerField(node).?;
158	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.type_only);
159	if (full.ast.align_expr != 0) {
160	_ = try astrl.expr(full.ast.align_expr, block, ResultInfo.type_only);
161	}
162	if (full.ast.value_expr != 0) {
163	_ = try astrl.expr(full.ast.value_expr, block, ResultInfo.type_only);
164	}
165	return false;
166	},
167	.@"usingnamespace" => {
168	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
169	return false;
170	},
171	.test_decl => {
172	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
173	return false;
174	},
175	.global_var_decl,
176	.local_var_decl,
177	.simple_var_decl,
178	.aligned_var_decl,
179	=> {
180	const full = tree.fullVarDecl(node).?;
181	const init_ri = if (full.ast.type_node != 0) init_ri: {
182	_ = try astrl.expr(full.ast.type_node, block, ResultInfo.type_only);
183	break :init_ri ResultInfo.typed_ptr;
184	} else ResultInfo.inferred_ptr;
185	if (full.ast.init_node == 0) {
186	// No init node, so we're done.
187	return false;
188	}
189	switch (token_tags[full.ast.mut_token]) {
190	.keyword_const => {
191	const init_consumes_rl = try astrl.expr(full.ast.init_node, block, init_ri);
192	if (init_consumes_rl) {
193	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
194	}
195	return false;
196	},
197	.keyword_var => {
198	// We'll create an alloc either way, so don't care if the
199	// result pointer is consumed.
200	_ = try astrl.expr(full.ast.init_node, block, init_ri);
201	return false;
202	},
203	else => unreachable,
204	}
205	},
206	.assign_destructure => {
207	const lhs_count = tree.extra_data[node_datas[node].lhs];
208	const all_lhs = tree.extra_data[node_datas[node].lhs + 1 ..][0..lhs_count];
209	for (all_lhs) \|lhs\| {
210	_ = try astrl.expr(lhs, block, ResultInfo.none);
211	}
212	// We don't need to gather any meaningful data here, because destructures always use RLS
213	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
214	return false;
215	},
216	.assign => {
217	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
218	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.typed_ptr);
219	return false;
220	},
221	.assign_shl,
222	.assign_shl_sat,
223	.assign_shr,
224	.assign_bit_and,
225	.assign_bit_or,
226	.assign_bit_xor,
227	.assign_div,
228	.assign_sub,
229	.assign_sub_wrap,
230	.assign_sub_sat,
231	.assign_mod,
232	.assign_add,
233	.assign_add_wrap,
234	.assign_add_sat,
235	.assign_mul,
236	.assign_mul_wrap,
237	.assign_mul_sat,
238	=> {
239	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
240	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
241	return false;
242	},
243	.shl, .shr => {
244	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
245	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
246	return false;
247	},
248	.add,
249	.add_wrap,
250	.add_sat,
251	.sub,
252	.sub_wrap,
253	.sub_sat,
254	.mul,
255	.mul_wrap,
256	.mul_sat,
257	.div,
258	.mod,
259	.shl_sat,
260	.bit_and,
261	.bit_or,
262	.bit_xor,
263	.bang_equal,
264	.equal_equal,
265	.greater_than,
266	.greater_or_equal,
267	.less_than,
268	.less_or_equal,
269	.array_cat,
270	=> {
271	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
272	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
273	return false;
274	},
275	.array_mult => {
276	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
277	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
278	return false;
279	},
280	.error_union, .merge_error_sets => {
281	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
282	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
283	return false;
284	},
285	.bool_and,
286	.bool_or,
287	=> {
288	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
289	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
290	return false;
291	},
292	.bool_not => {
293	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
294	return false;
295	},
296	.bit_not, .negation, .negation_wrap => {
297	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
298	return false;
299	},
300
301	// These nodes are leaves and never consume a result location.
302	.identifier,
303	.string_literal,
304	.multiline_string_literal,
305	.number_literal,
306	.unreachable_literal,
307	.asm_simple,
308	.@"asm",
309	.enum_literal,
310	.error_value,
311	.anyframe_literal,
312	.@"continue",
313	.char_literal,
314	.error_set_decl,
315	=> return false,
316
317	.builtin_call_two, .builtin_call_two_comma => {
318	if (node_datas[node].lhs == 0) {
319	return astrl.builtinCall(block, ri, node, &.{});
320	} else if (node_datas[node].rhs == 0) {
321	return astrl.builtinCall(block, ri, node, &.{node_datas[node].lhs});
322	} else {
323	return astrl.builtinCall(block, ri, node, &.{ node_datas[node].lhs, node_datas[node].rhs });
324	}
325	},
326	.builtin_call, .builtin_call_comma => {
327	const params = tree.extra_data[node_datas[node].lhs..node_datas[node].rhs];
328	return astrl.builtinCall(block, ri, node, params);
329	},
330
331	.call_one,
332	.call_one_comma,
333	.async_call_one,
334	.async_call_one_comma,
335	.call,
336	.call_comma,
337	.async_call,
338	.async_call_comma,
339	=> {
340	var buf: [1]Ast.Node.Index = undefined;
341	const full = tree.fullCall(&buf, node).?;
342	_ = try astrl.expr(full.ast.fn_expr, block, ResultInfo.none);
343	for (full.ast.params) \|param_node\| {
344	_ = try astrl.expr(param_node, block, ResultInfo.type_only);
345	}
346	return switch (node_tags[node]) {
347	.call_one,
348	.call_one_comma,
349	.call,
350	.call_comma,
351	=> false, // TODO: once function calls are passed result locations this will change
352	.async_call_one,
353	.async_call_one_comma,
354	.async_call,
355	.async_call_comma,
356	=> ri.have_ptr, // always use result ptr for frames
357	else => unreachable,
358	};
359	},
360
361	.@"return" => {
362	if (node_datas[node].lhs != 0) {
363	const ret_val_consumes_rl = try astrl.expr(node_datas[node].lhs, block, ResultInfo.typed_ptr);
364	if (ret_val_consumes_rl) {
365	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
366	}
367	}
368	return false;
369	},
370
371	.field_access => {
372	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
373	return false;
374	},
375
376	.if_simple, .@"if" => {
377	const full = tree.fullIf(node).?;
378	if (full.error_token != null or full.payload_token != null) {
379	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.none);
380	} else {
381	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.type_only); // bool
382	}
383
384	if (full.ast.else_expr == 0) {
385	_ = try astrl.expr(full.ast.then_expr, block, ResultInfo.none);
386	return false;
387	} else {
388	const then_uses_rl = try astrl.expr(full.ast.then_expr, block, ri);
389	const else_uses_rl = try astrl.expr(full.ast.else_expr, block, ri);
390	const uses_rl = then_uses_rl or else_uses_rl;
391	if (uses_rl) try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
392	return uses_rl;
393	}
394	},
395
396	.while_simple, .while_cont, .@"while" => {
397	const full = tree.fullWhile(node).?;
398	const label: ?[]const u8 = if (full.label_token) \|label_token\| label: {
399	break :label try astrl.identString(label_token);
400	} else null;
401	if (full.error_token != null or full.payload_token != null) {
402	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.none);
403	} else {
404	_ = try astrl.expr(full.ast.cond_expr, block, ResultInfo.type_only); // bool
405	}
406	var new_block: Block = .{
407	.parent = block,
408	.label = label,
409	.is_loop = true,
410	.ri = ri,
411	.consumes_res_ptr = false,
412	};
413	if (full.ast.cont_expr != 0) {
414	_ = try astrl.expr(full.ast.cont_expr, &new_block, ResultInfo.none);
415	}
416	_ = try astrl.expr(full.ast.then_expr, &new_block, ResultInfo.none);
417	const else_consumes_rl = if (full.ast.else_expr != 0) else_rl: {
418	break :else_rl try astrl.expr(full.ast.else_expr, block, ri);
419	} else false;
420	if (new_block.consumes_res_ptr or else_consumes_rl) {
421	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
422	return true;
423	} else {
424	return false;
425	}
426	},
427
428	.for_simple, .@"for" => {
429	const full = tree.fullFor(node).?;
430	const label: ?[]const u8 = if (full.label_token) \|label_token\| label: {
431	break :label try astrl.identString(label_token);
432	} else null;
433	for (full.ast.inputs) \|input\| {
434	if (node_tags[input] == .for_range) {
435	_ = try astrl.expr(node_datas[input].lhs, block, ResultInfo.type_only);
436	if (node_datas[input].rhs != 0) {
437	_ = try astrl.expr(node_datas[input].rhs, block, ResultInfo.type_only);
438	}
439	} else {
440	_ = try astrl.expr(input, block, ResultInfo.none);
441	}
442	}
443	var new_block: Block = .{
444	.parent = block,
445	.label = label,
446	.is_loop = true,
447	.ri = ri,
448	.consumes_res_ptr = false,
449	};
450	_ = try astrl.expr(full.ast.then_expr, &new_block, ResultInfo.none);
451	const else_consumes_rl = if (full.ast.else_expr != 0) else_rl: {
452	break :else_rl try astrl.expr(full.ast.else_expr, block, ri);
453	} else false;
454	if (new_block.consumes_res_ptr or else_consumes_rl) {
455	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
456	return true;
457	} else {
458	return false;
459	}
460	},
461
462	.slice_open => {
463	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
464	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
465	return false;
466	},
467	.slice => {
468	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.Slice);
469	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
470	_ = try astrl.expr(extra.start, block, ResultInfo.type_only);
471	_ = try astrl.expr(extra.end, block, ResultInfo.type_only);
472	return false;
473	},
474	.slice_sentinel => {
475	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SliceSentinel);
476	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
477	_ = try astrl.expr(extra.start, block, ResultInfo.type_only);
478	if (extra.end != 0) {
479	_ = try astrl.expr(extra.end, block, ResultInfo.type_only);
480	}
481	_ = try astrl.expr(extra.sentinel, block, ResultInfo.none);
482	return false;
483	},
484	.deref => {
485	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
486	return false;
487	},
488	.address_of => {
489	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
490	return false;
491	},
492	.optional_type => {
493	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
494	return false;
495	},
496	.grouped_expression,
497	.@"try",
498	.@"await",
499	.@"nosuspend",
500	.unwrap_optional,
501	=> return astrl.expr(node_datas[node].lhs, block, ri),
502
503	.block_two, .block_two_semicolon => {
504	if (node_datas[node].lhs == 0) {
505	return astrl.blockExpr(block, ri, node, &.{});
506	} else if (node_datas[node].rhs == 0) {
507	return astrl.blockExpr(block, ri, node, &.{node_datas[node].lhs});
508	} else {
509	return astrl.blockExpr(block, ri, node, &.{ node_datas[node].lhs, node_datas[node].rhs });
510	}
511	},
512	.block, .block_semicolon => {
513	const statements = tree.extra_data[node_datas[node].lhs..node_datas[node].rhs];
514	return astrl.blockExpr(block, ri, node, statements);
515	},
516	.anyframe_type => {
517	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
518	return false;
519	},
520	.@"catch", .@"orelse" => {
521	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
522	const rhs_consumes_rl = try astrl.expr(node_datas[node].rhs, block, ri);
523	if (rhs_consumes_rl) {
524	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
525	}
526	return rhs_consumes_rl;
527	},
528
529	.ptr_type_aligned,
530	.ptr_type_sentinel,
531	.ptr_type,
532	.ptr_type_bit_range,
533	=> {
534	const full = tree.fullPtrType(node).?;
535	_ = try astrl.expr(full.ast.child_type, block, ResultInfo.type_only);
536	if (full.ast.sentinel != 0) {
537	_ = try astrl.expr(full.ast.sentinel, block, ResultInfo.type_only);
538	}
539	if (full.ast.addrspace_node != 0) {
540	_ = try astrl.expr(full.ast.addrspace_node, block, ResultInfo.type_only);
541	}
542	if (full.ast.align_node != 0) {
543	_ = try astrl.expr(full.ast.align_node, block, ResultInfo.type_only);
544	}
545	if (full.ast.bit_range_start != 0) {
546	assert(full.ast.bit_range_end != 0);
547	_ = try astrl.expr(full.ast.bit_range_start, block, ResultInfo.type_only);
548	_ = try astrl.expr(full.ast.bit_range_end, block, ResultInfo.type_only);
549	}
550	return false;
551	},
552
553	.container_decl,
554	.container_decl_trailing,
555	.container_decl_arg,
556	.container_decl_arg_trailing,
557	.container_decl_two,
558	.container_decl_two_trailing,
559	.tagged_union,
560	.tagged_union_trailing,
561	.tagged_union_enum_tag,
562	.tagged_union_enum_tag_trailing,
563	.tagged_union_two,
564	.tagged_union_two_trailing,
565	=> {
566	var buf: [2]Ast.Node.Index = undefined;
567	try astrl.containerDecl(block, tree.fullContainerDecl(&buf, node).?);
568	return false;
569	},
570
571	.@"break" => {
572	if (node_datas[node].rhs == 0) {
573	// Breaks with void are not interesting
574	return false;
575	}
576
577	var opt_cur_block = block;
578	if (node_datas[node].lhs == 0) {
579	// No label - we're breaking from a loop.
580	while (opt_cur_block) \|cur_block\| : (opt_cur_block = cur_block.parent) {
581	if (cur_block.is_loop) break;
582	}
583	} else {
584	const break_label = try astrl.identString(node_datas[node].lhs);
585	while (opt_cur_block) \|cur_block\| : (opt_cur_block = cur_block.parent) {
586	const block_label = cur_block.label orelse continue;
587	if (std.mem.eql(u8, block_label, break_label)) break;
588	}
589	}
590
591	if (opt_cur_block) \|target_block\| {
592	const consumes_break_rl = try astrl.expr(node_datas[node].rhs, block, target_block.ri);
593	if (consumes_break_rl) target_block.consumes_res_ptr = true;
594	} else {
595	// No corresponding scope to break from - AstGen will emit an error.
596	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.none);
597	}
598
599	return false;
600	},
601
602	.array_type => {
603	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
604	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
605	return false;
606	},
607	.array_type_sentinel => {
608	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.ArrayTypeSentinel);
609	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.type_only);
610	_ = try astrl.expr(extra.elem_type, block, ResultInfo.type_only);
611	_ = try astrl.expr(extra.sentinel, block, ResultInfo.type_only);
612	return false;
613	},
614	.array_access => {
615	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
616	_ = try astrl.expr(node_datas[node].rhs, block, ResultInfo.type_only);
617	return false;
618	},
619	.@"comptime" => {
620	// AstGen will emit an error if the scope is already comptime, so we can assume it is
621	// not. This means the result location is not forwarded.
622	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
623	return false;
624	},
625	.@"switch", .switch_comma => {
626	const operand_node = node_datas[node].lhs;
627	const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SubRange);
628	const case_nodes = tree.extra_data[extra.start..extra.end];
629
630	_ = try astrl.expr(operand_node, block, ResultInfo.none);
631
632	var any_prong_consumed_rl = false;
633	for (case_nodes) \|case_node\| {
634	const case = tree.fullSwitchCase(case_node).?;
635	for (case.ast.values) \|item_node\| {
636	if (node_tags[item_node] == .switch_range) {
637	_ = try astrl.expr(node_datas[item_node].lhs, block, ResultInfo.none);
638	_ = try astrl.expr(node_datas[item_node].rhs, block, ResultInfo.none);
639	} else {
640	_ = try astrl.expr(item_node, block, ResultInfo.none);
641	}
642	}
643	if (try astrl.expr(case.ast.target_expr, block, ri)) {
644	any_prong_consumed_rl = true;
645	}
646	}
647	if (any_prong_consumed_rl) {
648	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
649	}
650	return any_prong_consumed_rl;
651	},
652	.@"suspend" => {
653	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
654	return false;
655	},
656	.@"resume" => {
657	_ = try astrl.expr(node_datas[node].lhs, block, ResultInfo.none);
658	return false;
659	},
660
661	.array_init_one,
662	.array_init_one_comma,
663	.array_init_dot_two,
664	.array_init_dot_two_comma,
665	.array_init_dot,
666	.array_init_dot_comma,
667	.array_init,
668	.array_init_comma,
669	=> {
670	var buf: [2]Ast.Node.Index = undefined;
671	const full = tree.fullArrayInit(&buf, node).?;
672
673	if (full.ast.type_expr != 0) {
674	// Explicitly typed init does not participate in RLS
675	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.none);
676	for (full.ast.elements) \|elem_init\| {
677	_ = try astrl.expr(elem_init, block, ResultInfo.type_only);
678	}
679	return false;
680	}
681
682	if (ri.have_type) {
683	// Always forward type information
684	// If we have a result pointer, we use and forward it
685	for (full.ast.elements) \|elem_init\| {
686	_ = try astrl.expr(elem_init, block, ri);
687	}
688	return ri.have_ptr;
689	} else {
690	// Untyped init does not consume result location
691	for (full.ast.elements) \|elem_init\| {
692	_ = try astrl.expr(elem_init, block, ResultInfo.none);
693	}
694	return false;
695	}
696	},
697
698	.struct_init_one,
699	.struct_init_one_comma,
700	.struct_init_dot_two,
701	.struct_init_dot_two_comma,
702	.struct_init_dot,
703	.struct_init_dot_comma,
704	.struct_init,
705	.struct_init_comma,
706	=> {
707	var buf: [2]Ast.Node.Index = undefined;
708	const full = tree.fullStructInit(&buf, node).?;
709
710	if (full.ast.type_expr != 0) {
711	// Explicitly typed init does not participate in RLS
712	_ = try astrl.expr(full.ast.type_expr, block, ResultInfo.none);
713	for (full.ast.fields) \|field_init\| {
714	_ = try astrl.expr(field_init, block, ResultInfo.type_only);
715	}
716	return false;
717	}
718
719	if (ri.have_type) {
720	// Always forward type information
721	// If we have a result pointer, we use and forward it
722	for (full.ast.fields) \|field_init\| {
723	_ = try astrl.expr(field_init, block, ri);
724	}
725	return ri.have_ptr;
726	} else {
727	// Untyped init does not consume result location
728	for (full.ast.fields) \|field_init\| {
729	_ = try astrl.expr(field_init, block, ResultInfo.none);
730	}
731	return false;
732	}
733	},
734
735	.fn_proto_simple,
736	.fn_proto_multi,
737	.fn_proto_one,
738	.fn_proto,
739	.fn_decl,
740	=> {
741	var buf: [1]Ast.Node.Index = undefined;
742	const full = tree.fullFnProto(&buf, node).?;
743	const body_node = if (node_tags[node] == .fn_decl) node_datas[node].rhs else 0;
744	{
745	var it = full.iterate(tree);
746	while (it.next()) \|param\| {
747	if (param.anytype_ellipsis3 == null) {
748	_ = try astrl.expr(param.type_expr, block, ResultInfo.type_only);
749	}
750	}
751	}
752	if (full.ast.align_expr != 0) {
753	_ = try astrl.expr(full.ast.align_expr, block, ResultInfo.type_only);
754	}
755	if (full.ast.addrspace_expr != 0) {
756	_ = try astrl.expr(full.ast.addrspace_expr, block, ResultInfo.type_only);
757	}
758	if (full.ast.section_expr != 0) {
759	_ = try astrl.expr(full.ast.section_expr, block, ResultInfo.type_only);
760	}
761	if (full.ast.callconv_expr != 0) {
762	_ = try astrl.expr(full.ast.callconv_expr, block, ResultInfo.type_only);
763	}
764	_ = try astrl.expr(full.ast.return_type, block, ResultInfo.type_only);
765	if (body_node != 0) {
766	_ = try astrl.expr(body_node, block, ResultInfo.none);
767	}
768	return false;
769	},
770	}
771	}
772
773	fn identString(astrl: *AstRlAnnotate, token: Ast.TokenIndex) ![]const u8 {
774	const tree = astrl.tree;
775	const token_tags = tree.tokens.items(.tag);
776	assert(token_tags[token] == .identifier);
777	const ident_name = tree.tokenSlice(token);
778	if (!std.mem.startsWith(u8, ident_name, "@")) {
779	return ident_name;
780	}
781	return std.zig.string_literal.parseAlloc(astrl.arena, ident_name[1..]) catch \|err\| switch (err) {
782	error.OutOfMemory => error.OutOfMemory,
783	error.InvalidLiteral => "", // This pass can safely return garbage on invalid AST
784	};
785	}
786
787	fn blockExpr(astrl: AstRlAnnotate, parent_block: ?Block, ri: ResultInfo, node: Ast.Node.Index, statements: []const Ast.Node.Index) !bool {
788	const tree = astrl.tree;
789	const token_tags = tree.tokens.items(.tag);
790	const main_tokens = tree.nodes.items(.main_token);
791
792	const lbrace = main_tokens[node];
793	if (token_tags[lbrace - 1] == .colon and
794	token_tags[lbrace - 2] == .identifier)
795	{
796	// Labeled block
797	var new_block: Block = .{
798	.parent = parent_block,
799	.label = try astrl.identString(lbrace - 2),
800	.is_loop = false,
801	.ri = ri,
802	.consumes_res_ptr = false,
803	};
804	for (statements) \|statement\| {
805	_ = try astrl.expr(statement, &new_block, ResultInfo.none);
806	}
807	if (new_block.consumes_res_ptr) {
808	try astrl.nodes_need_rl.putNoClobber(astrl.gpa, node, {});
809	}
810	return new_block.consumes_res_ptr;
811	} else {
812	// Unlabeled block
813	for (statements) \|statement\| {
814	_ = try astrl.expr(statement, parent_block, ResultInfo.none);
815	}
816	return false;
817	}
818	}
819
820	fn builtinCall(astrl: AstRlAnnotate, block: ?Block, ri: ResultInfo, node: Ast.Node.Index, args: []const Ast.Node.Index) !bool {
821	_ = ri; // Currently, no builtin consumes its result location.
822
823	const tree = astrl.tree;
824	const main_tokens = tree.nodes.items(.main_token);
825	const builtin_token = main_tokens[node];
826	const builtin_name = tree.tokenSlice(builtin_token);
827	const info = BuiltinFn.list.get(builtin_name) orelse return false;
828	if (info.param_count) \|expected\| {
829	if (expected != args.len) return false;
830	}
831	switch (info.tag) {
832	.import => return false,
833	.compile_log, .TypeOf => {
834	for (args) \|arg_node\| {
835	_ = try astrl.expr(arg_node, block, ResultInfo.none);
836	}
837	return false;
838	},
839	.as => {
840	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
841	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
842	return false;
843	},
844	.bit_cast => {
845	_ = try astrl.expr(args[0], block, ResultInfo.none);
846	return false;
847	},
848	.union_init => {
849	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
850	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
851	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
852	return false;
853	},
854	.c_import => {
855	_ = try astrl.expr(args[0], block, ResultInfo.none);
856	return false;
857	},
858	.min, .max => {
859	for (args) \|arg_node\| {
860	_ = try astrl.expr(arg_node, block, ResultInfo.none);
861	}
862	return false;
863	},
864	.@"export" => {
865	_ = try astrl.expr(args[0], block, ResultInfo.none);
866	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
867	return false;
868	},
869	.@"extern" => {
870	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
871	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
872	return false;
873	},
874	// These builtins take no args and do not consume the result pointer.
875	.src,
876	.This,
877	.return_address,
878	.error_return_trace,
879	.frame,
880	.breakpoint,
881	.in_comptime,
882	.panic,
883	.trap,
884	.c_va_start,
885	=> return false,
886	// TODO: this is a workaround for llvm/llvm-project#68409
887	// Zig tracking issue: #16876
888	.frame_address => return true,
889	// These builtins take a single argument with a known result type, but do not consume their
890	// result pointer.
891	.size_of,
892	.bit_size_of,
893	.align_of,
894	.compile_error,
895	.set_eval_branch_quota,
896	.int_from_bool,
897	.int_from_error,
898	.error_from_int,
899	.embed_file,
900	.error_name,
901	.set_runtime_safety,
902	.Type,
903	.c_undef,
904	.c_include,
905	.wasm_memory_size,
906	.splat,
907	.fence,
908	.set_float_mode,
909	.set_align_stack,
910	.set_cold,
911	.type_info,
912	.work_item_id,
913	.work_group_size,
914	.work_group_id,
915	=> {
916	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
917	return false;
918	},
919	// These builtins take a single argument with no result information and do not consume their
920	// result pointer.
921	.int_from_ptr,
922	.int_from_enum,
923	.sqrt,
924	.sin,
925	.cos,
926	.tan,
927	.exp,
928	.exp2,
929	.log,
930	.log2,
931	.log10,
932	.abs,
933	.floor,
934	.ceil,
935	.trunc,
936	.round,
937	.tag_name,
938	.type_name,
939	.Frame,
940	.frame_size,
941	.int_from_float,
942	.float_from_int,
943	.ptr_from_int,
944	.enum_from_int,
945	.float_cast,
946	.int_cast,
947	.truncate,
948	.error_cast,
949	.ptr_cast,
950	.align_cast,
951	.addrspace_cast,
952	.const_cast,
953	.volatile_cast,
954	.clz,
955	.ctz,
956	.pop_count,
957	.byte_swap,
958	.bit_reverse,
959	=> {
960	_ = try astrl.expr(args[0], block, ResultInfo.none);
961	return false;
962	},
963	.div_exact,
964	.div_floor,
965	.div_trunc,
966	.mod,
967	.rem,
968	=> {
969	_ = try astrl.expr(args[0], block, ResultInfo.none);
970	_ = try astrl.expr(args[1], block, ResultInfo.none);
971	return false;
972	},
973	.shl_exact, .shr_exact => {
974	_ = try astrl.expr(args[0], block, ResultInfo.none);
975	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
976	return false;
977	},
978	.bit_offset_of,
979	.offset_of,
980	.field_parent_ptr,
981	.has_decl,
982	.has_field,
983	.field,
984	=> {
985	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
986	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
987	return false;
988	},
989	.wasm_memory_grow => {
990	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
991	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
992	return false;
993	},
994	.c_define => {
995	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
996	_ = try astrl.expr(args[1], block, ResultInfo.none);
997	return false;
998	},
999	.reduce => {
1000	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1001	_ = try astrl.expr(args[1], block, ResultInfo.none);
1002	return false;
1003	},
1004	.add_with_overflow, .sub_with_overflow, .mul_with_overflow, .shl_with_overflow => {
1005	_ = try astrl.expr(args[0], block, ResultInfo.none);
1006	_ = try astrl.expr(args[1], block, ResultInfo.none);
1007	return false;
1008	},
1009	.atomic_load => {
1010	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1011	_ = try astrl.expr(args[1], block, ResultInfo.none);
1012	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1013	return false;
1014	},
1015	.atomic_rmw => {
1016	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1017	_ = try astrl.expr(args[1], block, ResultInfo.none);
1018	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1019	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1020	_ = try astrl.expr(args[4], block, ResultInfo.type_only);
1021	return false;
1022	},
1023	.atomic_store => {
1024	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1025	_ = try astrl.expr(args[1], block, ResultInfo.none);
1026	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1027	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1028	return false;
1029	},
1030	.mul_add => {
1031	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1032	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1033	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1034	return false;
1035	},
1036	.call => {
1037	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1038	_ = try astrl.expr(args[1], block, ResultInfo.none);
1039	_ = try astrl.expr(args[2], block, ResultInfo.none);
1040	return false;
1041	},
1042	.memcpy => {
1043	_ = try astrl.expr(args[0], block, ResultInfo.none);
1044	_ = try astrl.expr(args[1], block, ResultInfo.none);
1045	return false;
1046	},
1047	.memset => {
1048	_ = try astrl.expr(args[0], block, ResultInfo.none);
1049	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1050	return false;
1051	},
1052	.shuffle => {
1053	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1054	_ = try astrl.expr(args[1], block, ResultInfo.none);
1055	_ = try astrl.expr(args[2], block, ResultInfo.none);
1056	_ = try astrl.expr(args[3], block, ResultInfo.none);
1057	return false;
1058	},
1059	.select => {
1060	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1061	_ = try astrl.expr(args[1], block, ResultInfo.none);
1062	_ = try astrl.expr(args[2], block, ResultInfo.none);
1063	_ = try astrl.expr(args[3], block, ResultInfo.none);
1064	return false;
1065	},
1066	.async_call => {
1067	_ = try astrl.expr(args[0], block, ResultInfo.none);
1068	_ = try astrl.expr(args[1], block, ResultInfo.none);
1069	_ = try astrl.expr(args[2], block, ResultInfo.none);
1070	_ = try astrl.expr(args[3], block, ResultInfo.none);
1071	return false; // buffer passed as arg for frame data
1072	},
1073	.Vector => {
1074	_ = try astrl.expr(args[0], block, ResultInfo.type_only);
1075	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1076	return false;
1077	},
1078	.prefetch => {
1079	_ = try astrl.expr(args[0], block, ResultInfo.none);
1080	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1081	return false;
1082	},
1083	.c_va_arg => {
1084	_ = try astrl.expr(args[0], block, ResultInfo.none);
1085	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1086	return false;
1087	},
1088	.c_va_copy => {
1089	_ = try astrl.expr(args[0], block, ResultInfo.none);
1090	return false;
1091	},
1092	.c_va_end => {
1093	_ = try astrl.expr(args[0], block, ResultInfo.none);
1094	return false;
1095	},
1096	.cmpxchg_strong, .cmpxchg_weak => {
1097	_ = try astrl.expr(args[0], block, ResultInfo.none);
1098	_ = try astrl.expr(args[1], block, ResultInfo.type_only);
1099	_ = try astrl.expr(args[2], block, ResultInfo.type_only);
1100	_ = try astrl.expr(args[3], block, ResultInfo.type_only);
1101	_ = try astrl.expr(args[4], block, ResultInfo.type_only);
1102	return false;
1103	},
1104	}
1105	}