Commit ef2fa67ef018a4a49124a40e60941149efd34553 | zig

src/Module.zig+23-4

...	...	@@ -23,6 +23,8 @@ const trace = @import("tracy.zig").trace;
23	23	const astgen = @import("astgen.zig");
24	24	const zir_sema = @import("zir_sema.zig");
25	25
	26	const default_eval_branch_quota = 1000;
	27
26	28	/// General-purpose allocator. Used for both temporary and long-term storage.
27	29	gpa: *Allocator,
28	30	comp: *Compilation,
...	...	@@ -765,6 +767,8 @@ pub const Scope = struct {
765	767	label: ?Label = null,
766	768	inlining: ?*Inlining,
767	769	is_comptime: bool,
	770	/// Shared to sub-blocks.
	771	branch_quota: *u32,
768	772
769	773	pub const InstTable = std.AutoHashMap(zir.Inst, Inst);
770	774
...	...	@@ -792,8 +796,7 @@ pub const Scope = struct {
792	796
793	797	pub const Shared = struct {
794	798	caller: ?*Fn,
795		branch_count: u64,
796		branch_quota: u64,
	799	branch_count: u32,
797	800	};
798	801	};
799	802
...	...	@@ -1104,6 +1107,8 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1104	1107	var inst_table = Scope.Block.InstTable.init(self.gpa);
1105	1108	defer inst_table.deinit();
1106	1109
	1110	var branch_quota: u32 = default_eval_branch_quota;
	1111
1107	1112	var block_scope: Scope.Block = .{
1108	1113	.parent = null,
1109	1114	.inst_table = &inst_table,
...	...	@@ -1113,6 +1118,7 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1113	1118	.arena = &decl_arena.allocator,
1114	1119	.inlining = null,
1115	1120	.is_comptime = false,
	1121	.branch_quota = &branch_quota,
1116	1122	};
1117	1123	defer block_scope.instructions.deinit(self.gpa);
1118	1124
...	...	@@ -1297,6 +1303,8 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1297	1303	var decl_inst_table = Scope.Block.InstTable.init(self.gpa);
1298	1304	defer decl_inst_table.deinit();
1299	1305
	1306	var branch_quota: u32 = default_eval_branch_quota;
	1307
1300	1308	var block_scope: Scope.Block = .{
1301	1309	.parent = null,
1302	1310	.inst_table = &decl_inst_table,
...	...	@@ -1306,6 +1314,7 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1306	1314	.arena = &decl_arena.allocator,
1307	1315	.inlining = null,
1308	1316	.is_comptime = true,
	1317	.branch_quota = &branch_quota,
1309	1318	};
1310	1319	defer block_scope.instructions.deinit(self.gpa);
1311	1320
...	...	@@ -1367,6 +1376,7 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1367	1376	var var_inst_table = Scope.Block.InstTable.init(self.gpa);
1368	1377	defer var_inst_table.deinit();
1369	1378
	1379	var branch_quota_vi: u32 = default_eval_branch_quota;
1370	1380	var inner_block: Scope.Block = .{
1371	1381	.parent = null,
1372	1382	.inst_table = &var_inst_table,
...	...	@@ -1376,6 +1386,7 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1376	1386	.arena = &gen_scope_arena.allocator,
1377	1387	.inlining = null,
1378	1388	.is_comptime = true,
	1389	.branch_quota = &branch_quota_vi,
1379	1390	};
1380	1391	defer inner_block.instructions.deinit(self.gpa);
1381	1392	try zir_sema.analyzeBody(self, &inner_block, .{
...	...	@@ -1494,6 +1505,8 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1494	1505	var inst_table = Scope.Block.InstTable.init(self.gpa);
1495	1506	defer inst_table.deinit();
1496	1507
	1508	var branch_quota: u32 = default_eval_branch_quota;
	1509
1497	1510	var block_scope: Scope.Block = .{
1498	1511	.parent = null,
1499	1512	.inst_table = &inst_table,
...	...	@@ -1503,6 +1516,7 @@ fn astGenAndAnalyzeDecl(self: Module, decl: Decl) !bool {
1503	1516	.arena = &analysis_arena.allocator,
1504	1517	.inlining = null,
1505	1518	.is_comptime = true,
	1519	.branch_quota = &branch_quota,
1506	1520	};
1507	1521	defer block_scope.instructions.deinit(self.gpa);
1508	1522
...	...	@@ -1875,6 +1889,8 @@ pub fn analyzeFnBody(self: Module, decl: Decl, func: *Fn) !void {
1875	1889	defer decl.typed_value.most_recent.arena.?.* = arena.state;
1876	1890	var inst_table = Scope.Block.InstTable.init(self.gpa);
1877	1891	defer inst_table.deinit();
	1892	var branch_quota: u32 = default_eval_branch_quota;
	1893
1878	1894	var inner_block: Scope.Block = .{
1879	1895	.parent = null,
1880	1896	.inst_table = &inst_table,
...	...	@@ -1884,6 +1900,7 @@ pub fn analyzeFnBody(self: Module, decl: Decl, func: *Fn) !void {
1884	1900	.arena = &arena.allocator,
1885	1901	.inlining = null,
1886	1902	.is_comptime = false,
	1903	.branch_quota = &branch_quota,
1887	1904	};
1888	1905	defer inner_block.instructions.deinit(self.gpa);
1889	1906
...	...	@@ -3466,7 +3483,9 @@ pub fn addSafetyCheck(mod: Module, parent_block: Scope.Block, ok: *Inst, panic
3466	3483	.arena = parent_block.arena,
3467	3484	.inlining = parent_block.inlining,
3468	3485	.is_comptime = parent_block.is_comptime,
	3486	.branch_quota = parent_block.branch_quota,
3469	3487	};
	3488
3470	3489	defer fail_block.instructions.deinit(mod.gpa);
3471	3490
3472	3491	_ = try mod.safetyPanic(&fail_block, ok.src, panic_id);
...	...	@@ -3532,10 +3551,10 @@ pub fn identifierTokenString(mod: Module, scope: Scope, token: ast.TokenIndex)
3532	3551	pub fn emitBackwardBranch(mod: Module, block: Scope.Block, src: usize) !void {
3533	3552	const shared = block.inlining.?.shared;
3534	3553	shared.branch_count += 1;
3535		if (shared.branch_count > shared.branch_quota) {
	3554	if (shared.branch_count > block.branch_quota.*) {
3536	3555	// TODO show the "called from here" stack
3537	3556	return mod.fail(&block.base, src, "evaluation exceeded {d} backwards branches", .{
3538		shared.branch_quota,
	3557	block.branch_quota.*,
3539	3558	});
3540	3559	}
3541	3560	}

src/astgen.zig+15

...	...	@@ -2317,6 +2317,19 @@ fn compileError(mod: Module, scope: Scope, call: *ast.Node.BuiltinCall) InnerE
2317	2317	return addZIRUnOp(mod, scope, src, .compileerror, target);
2318	2318	}
2319	2319
	2320	fn setEvalBranchQuota(mod: Module, scope: Scope, call: ast.Node.BuiltinCall) InnerError!zir.Inst {
	2321	try ensureBuiltinParamCount(mod, scope, call, 1);
	2322	const tree = scope.tree();
	2323	const src = tree.token_locs[call.builtin_token].start;
	2324	const params = call.params();
	2325	const u32_type = try addZIRInstConst(mod, scope, src, .{
	2326	.ty = Type.initTag(.type),
	2327	.val = Value.initTag(.u32_type),
	2328	});
	2329	const quota = try expr(mod, scope, .{ .ty = u32_type }, params[0]);
	2330	return addZIRUnOp(mod, scope, src, .set_eval_branch_quota, quota);
	2331	}
	2332
2320	2333	fn typeOf(mod: Module, scope: Scope, rl: ResultLoc, call: ast.Node.BuiltinCall) InnerError!zir.Inst {
2321	2334	const tree = scope.tree();
2322	2335	const arena = scope.arena();
...	...	@@ -2362,6 +2375,8 @@ fn builtinCall(mod: Module, scope: Scope, rl: ResultLoc, call: *ast.Node.Built
2362	2375	return rlWrap(mod, scope, rl, try import(mod, scope, call));
2363	2376	} else if (mem.eql(u8, builtin_name, "@compileError")) {
2364	2377	return compileError(mod, scope, call);
	2378	} else if (mem.eql(u8, builtin_name, "@setEvalBranchQuota")) {
	2379	return setEvalBranchQuota(mod, scope, call);
2365	2380	} else {
2366	2381	return mod.failTok(scope, call.builtin_token, "invalid builtin function: '{s}'", .{builtin_name});
2367	2382	}

src/zir.zig+5

...	...	@@ -127,6 +127,9 @@ pub const Inst = struct {
127	127	coerce_to_ptr_elem,
128	128	/// Emit an error message and fail compilation.
129	129	compileerror,
	130	/// Changes the maximum number of backwards branches that compile-time
	131	/// code execution can use before giving up and making a compile error.
	132	set_eval_branch_quota,
130	133	/// Conditional branch. Splits control flow based on a boolean condition value.
131	134	condbr,
132	135	/// Special case, has no textual representation.
...	...	@@ -347,6 +350,7 @@ pub const Inst = struct {
347	350	.anyframe_type,
348	351	.bitnot,
349	352	.import,
	353	.set_eval_branch_quota,
350	354	=> UnOp,
351	355
352	356	.add,
...	...	@@ -535,6 +539,7 @@ pub const Inst = struct {
535	539	.switch_range,
536	540	.typeof_peer,
537	541	.resolve_inferred_alloc,
	542	.set_eval_branch_quota,
538	543	=> false,
539	544
540	545	.@"break",

src/zir_sema.zig+39-1

...	...	@@ -81,6 +81,7 @@ pub fn analyzeInst(mod: Module, scope: Scope, old_inst: *zir.Inst) InnerError!
81	81	.mut_slice_type => return analyzeInstSimplePtrType(mod, scope, old_inst.castTag(.mut_slice_type).?, true, .Slice),
82	82	.ptr_type => return analyzeInstPtrType(mod, scope, old_inst.castTag(.ptr_type).?),
83	83	.store => return analyzeInstStore(mod, scope, old_inst.castTag(.store).?),
	84	.set_eval_branch_quota => return analyzeInstSetEvalBranchQuota(mod, scope, old_inst.castTag(.set_eval_branch_quota).?),
84	85	.str => return analyzeInstStr(mod, scope, old_inst.castTag(.str).?),
85	86	.int => {
86	87	const big_int = old_inst.castTag(.int).?.positionals.int;
...	...	@@ -280,6 +281,24 @@ fn resolveType(mod: Module, scope: Scope, old_inst: *zir.Inst) !Type {
280	281	return val.toType(scope.arena());
281	282	}
282	283
	284	/// Appropriate to call when the coercion has already been done by result
	285	/// location semantics. Asserts the value fits in the provided `Int` type.
	286	/// Only supports `Int` types 64 bits or less.
	287	fn resolveAlreadyCoercedInt(
	288	mod: *Module,
	289	scope: *Scope,
	290	old_inst: *zir.Inst,
	291	comptime Int: type,
	292	) !Int {
	293	comptime assert(@typeInfo(Int).Int.bits <= 64);
	294	const new_inst = try resolveInst(mod, scope, old_inst);
	295	const val = try mod.resolveConstValue(scope, new_inst);
	296	switch (@typeInfo(Int).Int.signedness) {
	297	.signed => return @intCast(Int, val.toSignedInt()),
	298	.unsigned => return @intCast(Int, val.toUnsignedInt()),
	299	}
	300	}
	301
283	302	fn resolveInt(mod: Module, scope: Scope, old_inst: *zir.Inst, dest_type: Type) !u64 {
284	303	const new_inst = try resolveInst(mod, scope, old_inst);
285	304	const coerced = try mod.coerce(scope, dest_type, new_inst);
...	...	@@ -486,6 +505,18 @@ fn analyzeInstStoreToInferredPtr(
486	505	return mod.storePtr(scope, inst.base.src, bitcasted_ptr, value);
487	506	}
488	507
	508	fn analyzeInstSetEvalBranchQuota(
	509	mod: *Module,
	510	scope: *Scope,
	511	inst: *zir.Inst.UnOp,
	512	) InnerError!*Inst {
	513	const b = try mod.requireFunctionBlock(scope, inst.base.src);
	514	const quota = try resolveAlreadyCoercedInt(mod, scope, inst.positionals.operand, u32);
	515	if (b.branch_quota.* < quota)
	516	b.branch_quota.* = quota;
	517	return mod.constVoid(scope, inst.base.src);
	518	}
	519
489	520	fn analyzeInstStore(mod: Module, scope: Scope, inst: zir.Inst.BinOp) InnerError!Inst {
490	521	const ptr = try resolveInst(mod, scope, inst.positionals.lhs);
491	522	const value = try resolveInst(mod, scope, inst.positionals.rhs);
...	...	@@ -594,6 +625,7 @@ fn analyzeInstLoop(mod: Module, scope: Scope, inst: *zir.Inst.Loop) InnerError
594	625	.arena = parent_block.arena,
595	626	.inlining = parent_block.inlining,
596	627	.is_comptime = parent_block.is_comptime,
	628	.branch_quota = parent_block.branch_quota,
597	629	};
598	630	defer child_block.instructions.deinit(mod.gpa);
599	631
...	...	@@ -619,6 +651,7 @@ fn analyzeInstBlockFlat(mod: Module, scope: Scope, inst: *zir.Inst.Block, is_c
619	651	.label = null,
620	652	.inlining = parent_block.inlining,
621	653	.is_comptime = parent_block.is_comptime or is_comptime,
	654	.branch_quota = parent_block.branch_quota,
622	655	};
623	656	defer child_block.instructions.deinit(mod.gpa);
624	657
...	...	@@ -666,6 +699,7 @@ fn analyzeInstBlock(mod: Module, scope: Scope, inst: *zir.Inst.Block, is_compt
666	699	}),
667	700	.inlining = parent_block.inlining,
668	701	.is_comptime = is_comptime or parent_block.is_comptime,
	702	.branch_quota = parent_block.branch_quota,
669	703	};
670	704	const merges = &child_block.label.?.merges;
671	705
...	...	@@ -867,7 +901,6 @@ fn analyzeInstCall(mod: Module, scope: Scope, inst: *zir.Inst.Call) InnerError
867	901	// Otherwise we pass on the shared data from the parent scope.
868	902	var shared_inlining = Scope.Block.Inlining.Shared{
869	903	.branch_count = 0,
870		.branch_quota = 1000,
871	904	.caller = b.func,
872	905	};
873	906	// This one is shared among sub-blocks within the same callee, but not
...	...	@@ -896,7 +929,9 @@ fn analyzeInstCall(mod: Module, scope: Scope, inst: *zir.Inst.Call) InnerError
896	929	.label = null,
897	930	.inlining = &inlining,
898	931	.is_comptime = is_comptime_call,
	932	.branch_quota = b.branch_quota,
899	933	};
	934
900	935	const merges = &child_block.inlining.?.merges;
901	936
902	937	defer child_block.instructions.deinit(mod.gpa);
...	...	@@ -1417,6 +1452,7 @@ fn analyzeInstSwitchBr(mod: Module, scope: Scope, inst: *zir.Inst.SwitchBr) In
1417	1452	.arena = parent_block.arena,
1418	1453	.inlining = parent_block.inlining,
1419	1454	.is_comptime = parent_block.is_comptime,
	1455	.branch_quota = parent_block.branch_quota,
1420	1456	};
1421	1457	defer case_block.instructions.deinit(mod.gpa);
1422	1458
...	...	@@ -1960,6 +1996,7 @@ fn analyzeInstCondBr(mod: Module, scope: Scope, inst: *zir.Inst.CondBr) InnerE
1960	1996	.arena = parent_block.arena,
1961	1997	.inlining = parent_block.inlining,
1962	1998	.is_comptime = parent_block.is_comptime,
	1999	.branch_quota = parent_block.branch_quota,
1963	2000	};
1964	2001	defer true_block.instructions.deinit(mod.gpa);
1965	2002	try analyzeBody(mod, &true_block, inst.positionals.then_body);
...	...	@@ -1973,6 +2010,7 @@ fn analyzeInstCondBr(mod: Module, scope: Scope, inst: *zir.Inst.CondBr) InnerE
1973	2010	.arena = parent_block.arena,
1974	2011	.inlining = parent_block.inlining,
1975	2012	.is_comptime = parent_block.is_comptime,
	2013	.branch_quota = parent_block.branch_quota,
1976	2014	};
1977	2015	defer false_block.instructions.deinit(mod.gpa);
1978	2016	try analyzeBody(mod, &false_block, inst.positionals.else_body);

test/stage2/cbe.zig+15

...	...	@@ -67,7 +67,22 @@ pub fn addCases(ctx: *TestContext) !void {
67	67	\\}
68	68	, "");
69	69	}
	70	{
	71	var case = ctx.exeFromCompiledC("@setEvalBranchQuota", .{});
70	72
	73	case.addCompareOutput(
	74	\\export fn main() i32 {
	75	\\ @setEvalBranchQuota(1001);
	76	\\ const y = rec(1001);
	77	\\ return y - 1;
	78	\\}
	79	\\
	80	\\inline fn rec(n: usize) usize {
	81	\\ if (n <= 1) return n;
	82	\\ return rec(n - 1);
	83	\\}
	84	, "");
	85	}
71	86	ctx.c("empty start function", linux_x64,
72	87	\\export fn _start() noreturn {
73	88	\\ unreachable;

author	Andrew Kelley <andrew@ziglang.org> 2021-01-04 13:40:51-07:00
committer	Andrew Kelley <andrew@ziglang.org> 2021-01-04 13:40:51-07:00
log	ef2fa67ef018a4a49124a40e60941149efd34553
tree	5c5c538cf0b1d79e6626637ea5b3192e7cdec868
parent	aa0906e9aaaf36bc928b5502bdb34e7a0409b2c0
parent	7e64dc42215c93a2d1d6b7fa4f5e07b885788a7d

Merge branch 'g-w1-stage2-evalbranch'