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stage2: fix stack overflow in @setEvalBranchQuota test case

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Some of the reworkings in this branch put us over the limit, on Linux,
where the kernel disregards the fact that we ask for 16 MiB in the ELF
file. So we ask for more stack space in `main`.
This commit is contained in:
Andrew Kelley
2021-05-07 20:03:27 -07:00
parent 81d5104e22
commit d577654e66
3 changed files with 69 additions and 45 deletions
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2
src/Module.zig
View File

@@ -1088,7 +1088,7 @@ pub const Scope = struct {
/// for the one that will be the same for all Block instances.
src_decl: *Decl,
instructions: ArrayListUnmanaged(*ir.Inst),
label: ?Label = null,
label: ?*Label = null,
inlining: ?*Inlining,
is_comptime: bool,

100
src/Sema.zig
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@@ -1610,8 +1610,7 @@ fn zirLoop(sema: *Sema, parent_block: *Scope.Block, inst: Zir.Inst.Index) InnerE
.body = undefined,
};
var child_block = parent_block.makeSubBlock();
child_block.label = Scope.Block.Label{
var label: Scope.Block.Label = .{
.zir_block = inst,
.merges = .{
.results = .{},
@@ -1619,6 +1618,8 @@ fn zirLoop(sema: *Sema, parent_block: *Scope.Block, inst: Zir.Inst.Index) InnerE
.block_inst = block_inst,
},
};
var child_block = parent_block.makeSubBlock();
child_block.label = &label;
const merges = &child_block.label.?.merges;
defer child_block.instructions.deinit(sema.gpa);
@@ -1689,20 +1690,21 @@ fn zirBlock(sema: *Sema, parent_block: *Scope.Block, inst: Zir.Inst.Index) Inner
.body = undefined,
};
var label: Scope.Block.Label = .{
.zir_block = inst,
.merges = .{
.results = .{},
.br_list = .{},
.block_inst = block_inst,
},
};
var child_block: Scope.Block = .{
.parent = parent_block,
.sema = sema,
.src_decl = parent_block.src_decl,
.instructions = .{},
// TODO @as here is working around a stage1 miscompilation bug :(
.label = @as(?Scope.Block.Label, Scope.Block.Label{
.zir_block = inst,
.merges = .{
.results = .{},
.br_list = .{},
.block_inst = block_inst,
},
}),
.label = &label,
.inlining = parent_block.inlining,
.is_comptime = parent_block.is_comptime,
};
@@ -1895,7 +1897,7 @@ fn zirBreak(sema: *Sema, start_block: *Scope.Block, inst: Zir.Inst.Index) InnerE
var block = start_block;
while (true) {
if (block.label) |*label| {
if (block.label) |label| {
if (label.zir_block == zir_block) {
// Here we add a br instruction, but we over-allocate a little bit
// (if necessary) to make it possible to convert the instruction into
@@ -2084,26 +2086,38 @@ fn analyzeCall(
.block_inst = block_inst,
},
};
const callee_zir = module_fn.owner_decl.namespace.file_scope.zir;
var inline_sema: Sema = .{
.mod = sema.mod,
.gpa = sema.mod.gpa,
.arena = sema.arena,
.code = callee_zir,
.inst_map = try sema.gpa.alloc(*ir.Inst, callee_zir.instructions.len),
.owner_decl = sema.owner_decl,
.namespace = sema.owner_decl.namespace,
.owner_func = sema.owner_func,
.func = module_fn,
.param_inst_list = casted_args,
.branch_quota = sema.branch_quota,
.branch_count = sema.branch_count,
};
defer sema.gpa.free(inline_sema.inst_map);
// In order to save a bit of stack space, directly modify Sema rather
// than create a child one.
const parent_zir = sema.code;
sema.code = module_fn.owner_decl.namespace.file_scope.zir;
defer sema.code = parent_zir;
const parent_inst_map = sema.inst_map;
sema.inst_map = try sema.gpa.alloc(*ir.Inst, sema.code.instructions.len);
defer {
sema.gpa.free(sema.inst_map);
sema.inst_map = parent_inst_map;
}
const parent_namespace = sema.namespace;
sema.namespace = module_fn.owner_decl.namespace;
defer sema.namespace = parent_namespace;
const parent_func = sema.func;
sema.func = module_fn;
defer sema.func = parent_func;
const parent_param_inst_list = sema.param_inst_list;
sema.param_inst_list = casted_args;
defer sema.param_inst_list = parent_param_inst_list;
const parent_next_arg_index = sema.next_arg_index;
sema.next_arg_index = 0;
defer sema.next_arg_index = parent_next_arg_index;
var child_block: Scope.Block = .{
.parent = null,
.sema = &inline_sema,
.sema = sema,
.src_decl = module_fn.owner_decl,
.instructions = .{},
.label = null,
@@ -2117,16 +2131,13 @@ fn analyzeCall(
defer merges.results.deinit(sema.gpa);
defer merges.br_list.deinit(sema.gpa);
try inline_sema.emitBackwardBranch(&child_block, call_src);
try sema.emitBackwardBranch(&child_block, call_src);
// This will have return instructions analyzed as break instructions to
// the block_inst above.
try inline_sema.analyzeFnBody(&child_block, module_fn.zir_body_inst);
try sema.analyzeFnBody(&child_block, module_fn.zir_body_inst);
const result = try inline_sema.analyzeBlockBody(block, call_src, &child_block, merges);
sema.branch_quota = inline_sema.branch_quota;
sema.branch_count = inline_sema.branch_count;
const result = try sema.analyzeBlockBody(block, call_src, &child_block, merges);
break :res result;
} else res: {
@@ -3797,20 +3808,21 @@ fn analyzeSwitch(
.body = undefined,
};
var label: Scope.Block.Label = .{
.zir_block = switch_inst,
.merges = .{
.results = .{},
.br_list = .{},
.block_inst = block_inst,
},
};
var child_block: Scope.Block = .{
.parent = block,
.sema = sema,
.src_decl = block.src_decl,
.instructions = .{},
// TODO @as here is working around a stage1 miscompilation bug :(
.label = @as(?Scope.Block.Label, Scope.Block.Label{
.zir_block = switch_inst,
.merges = .{
.results = .{},
.br_list = .{},
.block_inst = block_inst,
},
}),
.label = &label,
.inlining = block.inlining,
.is_comptime = block.is_comptime,
};

12
src/main.zig
View File

@@ -180,6 +180,18 @@ pub fn mainArgs(gpa: *Allocator, arena: *Allocator, args: []const []const u8) !v
defer log_scopes.deinit(gpa);
if (@import("builtin").target.os.tag == .linux) {
// Linux does not respect the stack size specified in the ELF, so we
// have to do this at runtime. TODO move this code to start.zig using
// the GNU_STACK program header.
std.os.setrlimit(.STACK, .{
.cur = 16 * 1024 * 1024,
.max = 16 * 1024 * 1024,
}) catch |err| {
warn("unable to increase stack size to 16 MiB", .{});
};
}
const cmd = args[1];
const cmd_args = args[2..];
if (mem.eql(u8, cmd, "build-exe")) {