authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2018-04-18 22:21:54-04:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2018-04-18 22:21:54-04:00
log06909ceaab8ecb33d1f41049870797a3ae721610
tree921bdc2b695512725e60e028521cef2d386c93da
parentca4341f7ba845e7af3c6f2be52cd60c51ec6d68f

support break in suspend blocks

* you can label suspend blocks * labeled break supports suspend blocks See #803

9 files changed, 136 insertions(+), 13 deletions(-)

doc/langref.html.in+1-1
......@@ -5918,7 +5918,7 @@ Defer(body) = ("defer" | "deferror") body
59185918
59195919IfExpression(body) = "if" "(" Expression ")" body option("else" BlockExpression(body))
59205920
5921SuspendExpression(body) = "suspend" option(("|" Symbol "|" body))
5921SuspendExpression(body) = option(Symbol ":") "suspend" option(("|" Symbol "|" body))
59225922
59235923IfErrorExpression(body) = "if" "(" Expression ")" option("|" option("*") Symbol "|") body "else" "|" Symbol "|" BlockExpression(body)
59245924
src/all_types.hpp+13
......@@ -867,6 +867,7 @@ struct AstNodeAwaitExpr {
867867};
868868
869869struct AstNodeSuspend {
870 Buf *name;
870871 AstNode *block;
871872 AstNode *promise_symbol;
872873};
......@@ -1757,6 +1758,7 @@ enum ScopeId {
17571758 ScopeIdVarDecl,
17581759 ScopeIdCImport,
17591760 ScopeIdLoop,
1761 ScopeIdSuspend,
17601762 ScopeIdFnDef,
17611763 ScopeIdCompTime,
17621764 ScopeIdCoroPrelude,
......@@ -1852,6 +1854,17 @@ struct ScopeLoop {
18521854 ZigList<IrBasicBlock *> *incoming_blocks;
18531855};
18541856
1857// This scope is created for a suspend block in order to have labeled
1858// suspend for breaking out of a suspend and for detecting if a suspend
1859// block is inside a suspend block.
1860struct ScopeSuspend {
1861 Scope base;
1862
1863 Buf *name;
1864 IrBasicBlock *resume_block;
1865 bool reported_err;
1866};
1867
18551868// This scope is created for a comptime expression.
18561869// NodeTypeCompTime, NodeTypeSwitchExpr
18571870struct ScopeCompTime {
src/analyze.cpp+9
......@@ -156,6 +156,14 @@ ScopeLoop *create_loop_scope(AstNode *node, Scope *parent) {
156156 return scope;
157157}
158158
159ScopeSuspend *create_suspend_scope(AstNode *node, Scope *parent) {
160 assert(node->type == NodeTypeSuspend);
161 ScopeSuspend *scope = allocate<ScopeSuspend>(1);
162 init_scope(&scope->base, ScopeIdSuspend, node, parent);
163 scope->name = node->data.suspend.name;
164 return scope;
165}
166
159167ScopeFnDef *create_fndef_scope(AstNode *node, Scope *parent, FnTableEntry *fn_entry) {
160168 ScopeFnDef *scope = allocate<ScopeFnDef>(1);
161169 init_scope(&scope->base, ScopeIdFnDef, node, parent);
......@@ -3616,6 +3624,7 @@ FnTableEntry *scope_get_fn_if_root(Scope *scope) {
36163624 case ScopeIdVarDecl:
36173625 case ScopeIdCImport:
36183626 case ScopeIdLoop:
3627 case ScopeIdSuspend:
36193628 case ScopeIdCompTime:
36203629 case ScopeIdCoroPrelude:
36213630 scope = scope->parent;
src/analyze.hpp+1
......@@ -104,6 +104,7 @@ ScopeDeferExpr *create_defer_expr_scope(AstNode *node, Scope *parent);
104104Scope *create_var_scope(AstNode *node, Scope *parent, VariableTableEntry *var);
105105ScopeCImport *create_cimport_scope(AstNode *node, Scope *parent);
106106ScopeLoop *create_loop_scope(AstNode *node, Scope *parent);
107ScopeSuspend *create_suspend_scope(AstNode *node, Scope *parent);
107108ScopeFnDef *create_fndef_scope(AstNode *node, Scope *parent, FnTableEntry *fn_entry);
108109ScopeDecls *create_decls_scope(AstNode *node, Scope *parent, TypeTableEntry *container_type, ImportTableEntry *import);
109110Scope *create_comptime_scope(AstNode *node, Scope *parent);
src/codegen.cpp+1
......@@ -654,6 +654,7 @@ static ZigLLVMDIScope *get_di_scope(CodeGen *g, Scope *scope) {
654654 }
655655 case ScopeIdDeferExpr:
656656 case ScopeIdLoop:
657 case ScopeIdSuspend:
657658 case ScopeIdCompTime:
658659 case ScopeIdCoroPrelude:
659660 return get_di_scope(g, scope->parent);
src/ir.cpp+50-10
......@@ -2829,6 +2829,18 @@ static void ir_set_cursor_at_end_and_append_block(IrBuilder *irb, IrBasicBlock *
28292829 ir_set_cursor_at_end(irb, basic_block);
28302830}
28312831
2832static ScopeSuspend *get_scope_suspend(Scope *scope) {
2833 while (scope) {
2834 if (scope->id == ScopeIdSuspend)
2835 return (ScopeSuspend *)scope;
2836 if (scope->id == ScopeIdFnDef)
2837 return nullptr;
2838
2839 scope = scope->parent;
2840 }
2841 return nullptr;
2842}
2843
28322844static ScopeDeferExpr *get_scope_defer_expr(Scope *scope) {
28332845 while (scope) {
28342846 if (scope->id == ScopeIdDeferExpr)
......@@ -5665,6 +5677,15 @@ static IrInstruction *ir_gen_return_from_block(IrBuilder *irb, Scope *break_scop
56655677 return ir_build_br(irb, break_scope, node, dest_block, is_comptime);
56665678}
56675679
5680static IrInstruction *ir_gen_break_from_suspend(IrBuilder *irb, Scope *break_scope, AstNode *node, ScopeSuspend *suspend_scope) {
5681 IrInstruction *is_comptime = ir_build_const_bool(irb, break_scope, node, false);
5682
5683 IrBasicBlock *dest_block = suspend_scope->resume_block;
5684 ir_gen_defers_for_block(irb, break_scope, dest_block->scope, false);
5685
5686 return ir_build_br(irb, break_scope, node, dest_block, is_comptime);
5687}
5688
56685689static IrInstruction *ir_gen_break(IrBuilder *irb, Scope *break_scope, AstNode *node) {
56695690 assert(node->type == NodeTypeBreak);
56705691
......@@ -5704,6 +5725,13 @@ static IrInstruction *ir_gen_break(IrBuilder *irb, Scope *break_scope, AstNode *
57045725 assert(this_block_scope->end_block != nullptr);
57055726 return ir_gen_return_from_block(irb, break_scope, node, this_block_scope);
57065727 }
5728 } else if (search_scope->id == ScopeIdSuspend) {
5729 ScopeSuspend *this_suspend_scope = (ScopeSuspend *)search_scope;
5730 if (node->data.break_expr.name != nullptr &&
5731 (this_suspend_scope->name != nullptr && buf_eql_buf(node->data.break_expr.name, this_suspend_scope->name)))
5732 {
5733 return ir_gen_break_from_suspend(irb, break_scope, node, this_suspend_scope);
5734 }
57075735 }
57085736 search_scope = search_scope->parent;
57095737 }
......@@ -6290,14 +6318,26 @@ static IrInstruction *ir_gen_suspend(IrBuilder *irb, Scope *parent_scope, AstNod
62906318 ScopeDeferExpr *scope_defer_expr = get_scope_defer_expr(parent_scope);
62916319 if (scope_defer_expr) {
62926320 if (!scope_defer_expr->reported_err) {
6293 add_node_error(irb->codegen, node, buf_sprintf("cannot suspend inside defer expression"));
6321 ErrorMsg *msg = add_node_error(irb->codegen, node, buf_sprintf("cannot suspend inside defer expression"));
6322 add_error_note(irb->codegen, msg, scope_defer_expr->base.source_node, buf_sprintf("defer here"));
62946323 scope_defer_expr->reported_err = true;
62956324 }
62966325 return irb->codegen->invalid_instruction;
62976326 }
6327 ScopeSuspend *existing_suspend_scope = get_scope_suspend(parent_scope);
6328 if (existing_suspend_scope) {
6329 if (!existing_suspend_scope->reported_err) {
6330 ErrorMsg *msg = add_node_error(irb->codegen, node, buf_sprintf("cannot suspend inside suspend block"));
6331 add_error_note(irb->codegen, msg, existing_suspend_scope->base.source_node, buf_sprintf("other suspend block here"));
6332 existing_suspend_scope->reported_err = true;
6333 }
6334 return irb->codegen->invalid_instruction;
6335 }
62986336
62996337 Scope *outer_scope = irb->exec->begin_scope;
63006338
6339 IrBasicBlock *cleanup_block = ir_create_basic_block(irb, parent_scope, "SuspendCleanup");
6340 IrBasicBlock *resume_block = ir_create_basic_block(irb, parent_scope, "SuspendResume");
63016341
63026342 IrInstruction *suspend_code;
63036343 IrInstruction *const_bool_false = ir_build_const_bool(irb, parent_scope, node, false);
......@@ -6316,28 +6356,28 @@ static IrInstruction *ir_gen_suspend(IrBuilder *irb, Scope *parent_scope, AstNod
63166356 } else {
63176357 child_scope = parent_scope;
63186358 }
6359 ScopeSuspend *suspend_scope = create_suspend_scope(node, child_scope);
6360 suspend_scope->resume_block = resume_block;
6361 child_scope = &suspend_scope->base;
63196362 IrInstruction *save_token = ir_build_coro_save(irb, child_scope, node, irb->exec->coro_handle);
63206363 ir_gen_node(irb, node->data.suspend.block, child_scope);
6321 suspend_code = ir_build_coro_suspend(irb, parent_scope, node, save_token, const_bool_false);
6364 suspend_code = ir_mark_gen(ir_build_coro_suspend(irb, parent_scope, node, save_token, const_bool_false));
63226365 }
63236366
6324 IrBasicBlock *cleanup_block = ir_create_basic_block(irb, parent_scope, "SuspendCleanup");
6325 IrBasicBlock *resume_block = ir_create_basic_block(irb, parent_scope, "SuspendResume");
6326
63276367 IrInstructionSwitchBrCase *cases = allocate<IrInstructionSwitchBrCase>(2);
6328 cases[0].value = ir_build_const_u8(irb, parent_scope, node, 0);
6368 cases[0].value = ir_mark_gen(ir_build_const_u8(irb, parent_scope, node, 0));
63296369 cases[0].block = resume_block;
6330 cases[1].value = ir_build_const_u8(irb, parent_scope, node, 1);
6370 cases[1].value = ir_mark_gen(ir_build_const_u8(irb, parent_scope, node, 1));
63316371 cases[1].block = cleanup_block;
6332 ir_build_switch_br(irb, parent_scope, node, suspend_code, irb->exec->coro_suspend_block,
6333 2, cases, const_bool_false);
6372 ir_mark_gen(ir_build_switch_br(irb, parent_scope, node, suspend_code, irb->exec->coro_suspend_block,
6373 2, cases, const_bool_false));
63346374
63356375 ir_set_cursor_at_end_and_append_block(irb, cleanup_block);
63366376 ir_gen_defers_for_block(irb, parent_scope, outer_scope, true);
63376377 ir_mark_gen(ir_build_br(irb, parent_scope, node, irb->exec->coro_final_cleanup_block, const_bool_false));
63386378
63396379 ir_set_cursor_at_end_and_append_block(irb, resume_block);
6340 return ir_build_const_void(irb, parent_scope, node);
6380 return ir_mark_gen(ir_build_const_void(irb, parent_scope, node));
63416381}
63426382
63436383static IrInstruction *ir_gen_node_raw(IrBuilder *irb, AstNode *node, Scope *scope,
src/parser.cpp+23-2
......@@ -648,12 +648,30 @@ static AstNode *ast_parse_asm_expr(ParseContext *pc, size_t *token_index, bool m
648648}
649649
650650/*
651SuspendExpression(body) = "suspend" "|" Symbol "|" body
651SuspendExpression(body) = option(Symbol ":") "suspend" option(("|" Symbol "|" body))
652652*/
653653static AstNode *ast_parse_suspend_block(ParseContext *pc, size_t *token_index, bool mandatory) {
654654 size_t orig_token_index = *token_index;
655655
656 Token *suspend_token = &pc->tokens->at(*token_index);
656 Token *name_token = nullptr;
657 Token *token = &pc->tokens->at(*token_index);
658 if (token->id == TokenIdSymbol) {
659 *token_index += 1;
660 Token *colon_token = &pc->tokens->at(*token_index);
661 if (colon_token->id == TokenIdColon) {
662 *token_index += 1;
663 name_token = token;
664 token = &pc->tokens->at(*token_index);
665 } else if (mandatory) {
666 ast_expect_token(pc, colon_token, TokenIdColon);
667 zig_unreachable();
668 } else {
669 *token_index = orig_token_index;
670 return nullptr;
671 }
672 }
673
674 Token *suspend_token = token;
657675 if (suspend_token->id == TokenIdKeywordSuspend) {
658676 *token_index += 1;
659677 } else if (mandatory) {
......@@ -675,6 +693,9 @@ static AstNode *ast_parse_suspend_block(ParseContext *pc, size_t *token_index, b
675693 }
676694
677695 AstNode *node = ast_create_node(pc, NodeTypeSuspend, suspend_token);
696 if (name_token != nullptr) {
697 node->data.suspend.name = token_buf(name_token);
698 }
678699 node->data.suspend.promise_symbol = ast_parse_symbol(pc, token_index);
679700 ast_eat_token(pc, token_index, TokenIdBinOr);
680701 node->data.suspend.block = ast_parse_block(pc, token_index, true);
test/cases/coroutines.zig+18
......@@ -224,3 +224,21 @@ async fn printTrace(p: promise->error!void) void {
224224 }
225225 };
226226}
227
228test "break from suspend" {
229 var buf: [500]u8 = undefined;
230 var a = &std.heap.FixedBufferAllocator.init(buf[0..]).allocator;
231 var my_result: i32 = 1;
232 const p = try async<a> testBreakFromSuspend(&my_result);
233 cancel p;
234 std.debug.assert(my_result == 2);
235}
236
237async fn testBreakFromSuspend(my_result: &i32) void {
238 s: suspend |p| {
239 break :s;
240 }
241 *my_result += 1;
242 suspend;
243 *my_result += 1;
244}
test/compile_errors.zig+20
......@@ -1,6 +1,26 @@
11const tests = @import("tests.zig");
22
33pub fn addCases(cases: &tests.CompileErrorContext) void {
4 cases.add("suspend inside suspend block",
5 \\const std = @import("std");
6 \\
7 \\export fn entry() void {
8 \\ var buf: [500]u8 = undefined;
9 \\ var a = &std.heap.FixedBufferAllocator.init(buf[0..]).allocator;
10 \\ const p = (async<a> foo()) catch unreachable;
11 \\ cancel p;
12 \\}
13 \\
14 \\async fn foo() void {
15 \\ suspend |p| {
16 \\ suspend |p1| {
17 \\ }
18 \\ }
19 \\}
20 ,
21 ".tmp_source.zig:12:9: error: cannot suspend inside suspend block",
22 ".tmp_source.zig:11:5: note: other suspend block here");
23
424 cases.add("assign inline fn to non-comptime var",
525 \\export fn entry() void {
626 \\ var a = b;