Commit b1775ca168
Changed files (20)
src/all_types.hpp
@@ -544,12 +544,7 @@ struct AstNodeDefer {
};
struct AstNodeVariableDeclaration {
- VisibMod visib_mod;
Buf *symbol;
- bool is_const;
- bool is_comptime;
- bool is_export;
- bool is_extern;
// one or both of type and expr will be non null
AstNode *type;
AstNode *expr;
@@ -559,6 +554,13 @@ struct AstNodeVariableDeclaration {
AstNode *align_expr;
// populated if the "section(S)" is present
AstNode *section_expr;
+ Token *threadlocal_tok;
+
+ VisibMod visib_mod;
+ bool is_const;
+ bool is_comptime;
+ bool is_export;
+ bool is_extern;
};
struct AstNodeTestDecl {
@@ -1873,6 +1875,7 @@ struct ZigVar {
bool shadowable;
bool src_is_const;
bool gen_is_const;
+ bool is_thread_local;
};
struct ErrorTableEntry {
src/analyze.cpp
@@ -28,28 +28,10 @@ static Error ATTRIBUTE_MUST_USE resolve_enum_zero_bits(CodeGen *g, ZigType *enum
static Error ATTRIBUTE_MUST_USE resolve_union_zero_bits(CodeGen *g, ZigType *union_type);
static void analyze_fn_body(CodeGen *g, ZigFn *fn_table_entry);
-ErrorMsg *add_node_error(CodeGen *g, AstNode *node, Buf *msg) {
- if (node->owner->c_import_node != nullptr) {
- // if this happens, then translate_c generated code that
- // failed semantic analysis, which isn't supposed to happen
- ErrorMsg *err = add_node_error(g, node->owner->c_import_node,
- buf_sprintf("compiler bug: @cImport generated invalid zig code"));
-
- add_error_note(g, err, node, msg);
-
- g->errors.append(err);
- return err;
- }
-
- ErrorMsg *err = err_msg_create_with_line(node->owner->path, node->line, node->column,
- node->owner->source_code, node->owner->line_offsets, msg);
-
- g->errors.append(err);
- return err;
-}
-
-ErrorMsg *add_error_note(CodeGen *g, ErrorMsg *parent_msg, AstNode *node, Buf *msg) {
- if (node->owner->c_import_node != nullptr) {
+static ErrorMsg *add_error_note_token(CodeGen *g, ErrorMsg *parent_msg, ImportTableEntry *owner, Token *token,
+ Buf *msg)
+{
+ if (owner->c_import_node != nullptr) {
// if this happens, then translate_c generated code that
// failed semantic analysis, which isn't supposed to happen
@@ -64,13 +46,46 @@ ErrorMsg *add_error_note(CodeGen *g, ErrorMsg *parent_msg, AstNode *node, Buf *m
return note;
}
- ErrorMsg *err = err_msg_create_with_line(node->owner->path, node->line, node->column,
- node->owner->source_code, node->owner->line_offsets, msg);
+ ErrorMsg *err = err_msg_create_with_line(owner->path, token->start_line, token->start_column,
+ owner->source_code, owner->line_offsets, msg);
err_msg_add_note(parent_msg, err);
return err;
}
+ErrorMsg *add_token_error(CodeGen *g, ImportTableEntry *owner, Token *token, Buf *msg) {
+ if (owner->c_import_node != nullptr) {
+ // if this happens, then translate_c generated code that
+ // failed semantic analysis, which isn't supposed to happen
+ ErrorMsg *err = add_node_error(g, owner->c_import_node,
+ buf_sprintf("compiler bug: @cImport generated invalid zig code"));
+
+ add_error_note_token(g, err, owner, token, msg);
+
+ g->errors.append(err);
+ return err;
+ }
+ ErrorMsg *err = err_msg_create_with_line(owner->path, token->start_line, token->start_column,
+ owner->source_code, owner->line_offsets, msg);
+
+ g->errors.append(err);
+ return err;
+}
+
+ErrorMsg *add_node_error(CodeGen *g, AstNode *node, Buf *msg) {
+ Token fake_token;
+ fake_token.start_line = node->line;
+ fake_token.start_column = node->column;
+ return add_token_error(g, node->owner, &fake_token, msg);
+}
+
+ErrorMsg *add_error_note(CodeGen *g, ErrorMsg *parent_msg, AstNode *node, Buf *msg) {
+ Token fake_token;
+ fake_token.start_line = node->line;
+ fake_token.start_column = node->column;
+ return add_error_note_token(g, parent_msg, node->owner, &fake_token, msg);
+}
+
ZigType *new_type_table_entry(ZigTypeId id) {
ZigType *entry = allocate<ZigType>(1);
entry->id = id;
@@ -3668,6 +3683,7 @@ static void resolve_decl_var(CodeGen *g, TldVar *tld_var) {
bool is_const = var_decl->is_const;
bool is_extern = var_decl->is_extern;
bool is_export = var_decl->is_export;
+ bool is_thread_local = var_decl->threadlocal_tok != nullptr;
ZigType *explicit_type = nullptr;
if (var_decl->type) {
@@ -3727,6 +3743,7 @@ static void resolve_decl_var(CodeGen *g, TldVar *tld_var) {
tld_var->var = add_variable(g, source_node, tld_var->base.parent_scope, var_decl->symbol,
is_const, init_val, &tld_var->base, type);
tld_var->var->linkage = linkage;
+ tld_var->var->is_thread_local = is_thread_local;
if (implicit_type != nullptr && type_is_invalid(implicit_type)) {
tld_var->var->var_type = g->builtin_types.entry_invalid;
@@ -3747,6 +3764,10 @@ static void resolve_decl_var(CodeGen *g, TldVar *tld_var) {
}
}
+ if (is_thread_local && is_const) {
+ add_node_error(g, source_node, buf_sprintf("threadlocal variable cannot be constant"));
+ }
+
g->global_vars.append(tld_var);
}
src/analyze.hpp
@@ -12,6 +12,7 @@
void semantic_analyze(CodeGen *g);
ErrorMsg *add_node_error(CodeGen *g, AstNode *node, Buf *msg);
+ErrorMsg *add_token_error(CodeGen *g, ImportTableEntry *owner, Token *token, Buf *msg);
ErrorMsg *add_error_note(CodeGen *g, ErrorMsg *parent_msg, AstNode *node, Buf *msg);
ZigType *new_type_table_entry(ZigTypeId id);
ZigType *get_pointer_to_type(CodeGen *g, ZigType *child_type, bool is_const);
src/ast_render.cpp
@@ -132,6 +132,10 @@ static const char *const_or_var_string(bool is_const) {
return is_const ? "const" : "var";
}
+static const char *thread_local_string(Token *tok) {
+ return (tok == nullptr) ? "" : "threadlocal ";
+}
+
const char *container_string(ContainerKind kind) {
switch (kind) {
case ContainerKindEnum: return "enum";
@@ -554,8 +558,9 @@ static void render_node_extra(AstRender *ar, AstNode *node, bool grouped) {
{
const char *pub_str = visib_mod_string(node->data.variable_declaration.visib_mod);
const char *extern_str = extern_string(node->data.variable_declaration.is_extern);
+ const char *thread_local_str = thread_local_string(node->data.variable_declaration.threadlocal_tok);
const char *const_or_var = const_or_var_string(node->data.variable_declaration.is_const);
- fprintf(ar->f, "%s%s%s ", pub_str, extern_str, const_or_var);
+ fprintf(ar->f, "%s%s%s%s ", pub_str, extern_str, thread_local_str, const_or_var);
print_symbol(ar, node->data.variable_declaration.symbol);
if (node->data.variable_declaration.type) {
src/codegen.cpp
@@ -6445,6 +6445,9 @@ static void do_code_gen(CodeGen *g) {
maybe_import_dll(g, global_value, GlobalLinkageIdStrong);
LLVMSetAlignment(global_value, var->align_bytes);
LLVMSetGlobalConstant(global_value, var->gen_is_const);
+ if (var->is_thread_local && !g->is_single_threaded) {
+ LLVMSetThreadLocalMode(global_value, LLVMGeneralDynamicTLSModel);
+ }
}
} else {
bool exported = (var->linkage == VarLinkageExport);
@@ -6470,6 +6473,9 @@ static void do_code_gen(CodeGen *g) {
}
LLVMSetGlobalConstant(global_value, var->gen_is_const);
+ if (var->is_thread_local && !g->is_single_threaded) {
+ LLVMSetThreadLocalMode(global_value, LLVMGeneralDynamicTLSModel);
+ }
}
var->value_ref = global_value;
@@ -7520,6 +7526,7 @@ static Error define_builtin_compile_vars(CodeGen *g) {
g->compile_var_package = new_package(buf_ptr(this_dir), builtin_zig_basename);
g->root_package->package_table.put(buf_create_from_str("builtin"), g->compile_var_package);
g->std_package->package_table.put(buf_create_from_str("builtin"), g->compile_var_package);
+ g->std_package->package_table.put(buf_create_from_str("std"), g->std_package);
g->compile_var_import = add_source_file(g, g->compile_var_package, builtin_zig_path, contents);
scan_import(g, g->compile_var_import);
src/ir.cpp
@@ -5204,6 +5204,10 @@ static IrInstruction *ir_gen_var_decl(IrBuilder *irb, Scope *scope, AstNode *nod
add_node_error(irb->codegen, variable_declaration->section_expr,
buf_sprintf("cannot set section of local variable '%s'", buf_ptr(variable_declaration->symbol)));
}
+ if (variable_declaration->threadlocal_tok != nullptr) {
+ add_token_error(irb->codegen, node->owner, variable_declaration->threadlocal_tok,
+ buf_sprintf("function-local variable '%s' cannot be threadlocal", buf_ptr(variable_declaration->symbol)));
+ }
// Temporarily set the name of the IrExecutable to the VariableDeclaration
// so that the struct or enum from the init expression inherits the name.
src/parser.cpp
@@ -844,12 +844,17 @@ static AstNode *ast_parse_fn_proto(ParseContext *pc) {
// VarDecl <- (KEYWORD_const / KEYWORD_var) IDENTIFIER (COLON TypeExpr)? ByteAlign? LinkSection? (EQUAL Expr)? SEMICOLON
static AstNode *ast_parse_var_decl(ParseContext *pc) {
- Token *first = eat_token_if(pc, TokenIdKeywordConst);
- if (first == nullptr)
- first = eat_token_if(pc, TokenIdKeywordVar);
- if (first == nullptr)
- return nullptr;
-
+ Token *thread_local_kw = eat_token_if(pc, TokenIdKeywordThreadLocal);
+ Token *mut_kw = eat_token_if(pc, TokenIdKeywordConst);
+ if (mut_kw == nullptr)
+ mut_kw = eat_token_if(pc, TokenIdKeywordVar);
+ if (mut_kw == nullptr) {
+ if (thread_local_kw == nullptr) {
+ return nullptr;
+ } else {
+ ast_invalid_token_error(pc, peek_token(pc));
+ }
+ }
Token *identifier = expect_token(pc, TokenIdSymbol);
AstNode *type_expr = nullptr;
if (eat_token_if(pc, TokenIdColon) != nullptr)
@@ -863,8 +868,9 @@ static AstNode *ast_parse_var_decl(ParseContext *pc) {
expect_token(pc, TokenIdSemicolon);
- AstNode *res = ast_create_node(pc, NodeTypeVariableDeclaration, first);
- res->data.variable_declaration.is_const = first->id == TokenIdKeywordConst;
+ AstNode *res = ast_create_node(pc, NodeTypeVariableDeclaration, mut_kw);
+ res->data.variable_declaration.threadlocal_tok = thread_local_kw;
+ res->data.variable_declaration.is_const = mut_kw->id == TokenIdKeywordConst;
res->data.variable_declaration.symbol = token_buf(identifier);
res->data.variable_declaration.type = type_expr;
res->data.variable_declaration.align_expr = align_expr;
src/tokenizer.cpp
@@ -146,6 +146,7 @@ static const struct ZigKeyword zig_keywords[] = {
{"suspend", TokenIdKeywordSuspend},
{"switch", TokenIdKeywordSwitch},
{"test", TokenIdKeywordTest},
+ {"threadlocal", TokenIdKeywordThreadLocal},
{"true", TokenIdKeywordTrue},
{"try", TokenIdKeywordTry},
{"undefined", TokenIdKeywordUndefined},
@@ -1586,6 +1587,7 @@ const char * token_name(TokenId id) {
case TokenIdKeywordStruct: return "struct";
case TokenIdKeywordSwitch: return "switch";
case TokenIdKeywordTest: return "test";
+ case TokenIdKeywordThreadLocal: return "threadlocal";
case TokenIdKeywordTrue: return "true";
case TokenIdKeywordTry: return "try";
case TokenIdKeywordUndefined: return "undefined";
src/tokenizer.hpp
@@ -88,6 +88,7 @@ enum TokenId {
TokenIdKeywordSuspend,
TokenIdKeywordSwitch,
TokenIdKeywordTest,
+ TokenIdKeywordThreadLocal,
TokenIdKeywordTrue,
TokenIdKeywordTry,
TokenIdKeywordUndefined,
std/debug/index.zig
@@ -37,7 +37,6 @@ const Module = struct {
var stderr_file: os.File = undefined;
var stderr_file_out_stream: os.File.OutStream = undefined;
-/// TODO multithreaded awareness
var stderr_stream: ?*io.OutStream(os.File.WriteError) = null;
var stderr_mutex = std.Mutex.init();
pub fn warn(comptime fmt: []const u8, args: ...) void {
std/os/index.zig
@@ -8,6 +8,9 @@ const is_posix = switch (builtin.os) {
};
const os = @This();
+// See the comment in startup.zig for why this does not use the `std` global above.
+const startup = @import("std").startup;
+
test "std.os" {
_ = @import("child_process.zig");
_ = @import("darwin.zig");
@@ -667,14 +670,11 @@ fn posixExecveErrnoToErr(err: usize) PosixExecveError {
}
}
-pub var linux_elf_aux_maybe: ?[*]std.elf.Auxv = null;
-pub var posix_environ_raw: [][*]u8 = undefined;
-
/// See std.elf for the constants.
pub fn linuxGetAuxVal(index: usize) usize {
if (builtin.link_libc) {
return usize(std.c.getauxval(index));
- } else if (linux_elf_aux_maybe) |auxv| {
+ } else if (startup.linux_elf_aux_maybe) |auxv| {
var i: usize = 0;
while (auxv[i].a_type != std.elf.AT_NULL) : (i += 1) {
if (auxv[i].a_type == index)
@@ -692,12 +692,7 @@ pub fn getBaseAddress() usize {
return base;
}
const phdr = linuxGetAuxVal(std.elf.AT_PHDR);
- const ElfHeader = switch (@sizeOf(usize)) {
- 4 => std.elf.Elf32_Ehdr,
- 8 => std.elf.Elf64_Ehdr,
- else => @compileError("Unsupported architecture"),
- };
- return phdr - @sizeOf(ElfHeader);
+ return phdr - @sizeOf(std.elf.Ehdr);
},
builtin.Os.macosx, builtin.Os.freebsd => return @ptrToInt(&std.c._mh_execute_header),
builtin.Os.windows => return @ptrToInt(windows.GetModuleHandleW(null)),
@@ -739,7 +734,7 @@ pub fn getEnvMap(allocator: *Allocator) !BufMap {
try result.setMove(key, value);
}
} else {
- for (posix_environ_raw) |ptr| {
+ for (startup.posix_environ_raw) |ptr| {
var line_i: usize = 0;
while (ptr[line_i] != 0 and ptr[line_i] != '=') : (line_i += 1) {}
const key = ptr[0..line_i];
@@ -761,7 +756,7 @@ test "os.getEnvMap" {
/// TODO make this go through libc when we have it
pub fn getEnvPosix(key: []const u8) ?[]const u8 {
- for (posix_environ_raw) |ptr| {
+ for (startup.posix_environ_raw) |ptr| {
var line_i: usize = 0;
while (ptr[line_i] != 0 and ptr[line_i] != '=') : (line_i += 1) {}
const this_key = ptr[0..line_i];
@@ -1942,14 +1937,14 @@ pub const ArgIteratorPosix = struct {
pub fn init() ArgIteratorPosix {
return ArgIteratorPosix{
.index = 0,
- .count = raw.len,
+ .count = startup.posix_argv_raw.len,
};
}
pub fn next(self: *ArgIteratorPosix) ?[]const u8 {
if (self.index == self.count) return null;
- const s = raw[self.index];
+ const s = startup.posix_argv_raw[self.index];
self.index += 1;
return cstr.toSlice(s);
}
@@ -1960,10 +1955,6 @@ pub const ArgIteratorPosix = struct {
self.index += 1;
return true;
}
-
- /// This is marked as public but actually it's only meant to be used
- /// internally by zig's startup code.
- pub var raw: [][*]u8 = undefined;
};
pub const ArgIteratorWindows = struct {
@@ -2908,14 +2899,15 @@ pub const Thread = struct {
pub const Data = if (use_pthreads)
struct {
handle: Thread.Handle,
- stack_addr: usize,
- stack_len: usize,
+ mmap_addr: usize,
+ mmap_len: usize,
}
else switch (builtin.os) {
builtin.Os.linux => struct {
handle: Thread.Handle,
- stack_addr: usize,
- stack_len: usize,
+ mmap_addr: usize,
+ mmap_len: usize,
+ tls_end_addr: usize,
},
builtin.Os.windows => struct {
handle: Thread.Handle,
@@ -2955,7 +2947,7 @@ pub const Thread = struct {
posix.EDEADLK => unreachable,
else => unreachable,
}
- assert(posix.munmap(self.data.stack_addr, self.data.stack_len) == 0);
+ assert(posix.munmap(self.data.mmap_addr, self.data.mmap_len) == 0);
} else switch (builtin.os) {
builtin.Os.linux => {
while (true) {
@@ -2969,7 +2961,7 @@ pub const Thread = struct {
else => unreachable,
}
}
- assert(posix.munmap(self.data.stack_addr, self.data.stack_len) == 0);
+ assert(posix.munmap(self.data.mmap_addr, self.data.mmap_len) == 0);
},
builtin.Os.windows => {
assert(windows.WaitForSingleObject(self.data.handle, windows.INFINITE) == windows.WAIT_OBJECT_0);
@@ -3097,42 +3089,56 @@ pub fn spawnThread(context: var, comptime startFn: var) SpawnThreadError!*Thread
const MAP_GROWSDOWN = if (builtin.os == builtin.Os.linux) linux.MAP_GROWSDOWN else 0;
- const mmap_len = default_stack_size;
- const stack_addr = posix.mmap(null, mmap_len, posix.PROT_READ | posix.PROT_WRITE, posix.MAP_PRIVATE | posix.MAP_ANONYMOUS | MAP_GROWSDOWN, -1, 0);
- if (stack_addr == posix.MAP_FAILED) return error.OutOfMemory;
- errdefer assert(posix.munmap(stack_addr, mmap_len) == 0);
+ var stack_end_offset: usize = undefined;
+ var thread_start_offset: usize = undefined;
+ var context_start_offset: usize = undefined;
+ var tls_start_offset: usize = undefined;
+ const mmap_len = blk: {
+ // First in memory will be the stack, which grows downwards.
+ var l: usize = mem.alignForward(default_stack_size, os.page_size);
+ stack_end_offset = l;
+ // Above the stack, so that it can be in the same mmap call, put the Thread object.
+ l = mem.alignForward(l, @alignOf(Thread));
+ thread_start_offset = l;
+ l += @sizeOf(Thread);
+ // Next, the Context object.
+ if (@sizeOf(Context) != 0) {
+ l = mem.alignForward(l, @alignOf(Context));
+ context_start_offset = l;
+ l += @sizeOf(Context);
+ }
+ // Finally, the Thread Local Storage, if any.
+ if (!Thread.use_pthreads) {
+ if (startup.linux_tls_phdr) |tls_phdr| {
+ l = mem.alignForward(l, tls_phdr.p_align);
+ tls_start_offset = l;
+ l += tls_phdr.p_memsz;
+ }
+ }
+ break :blk l;
+ };
+ const mmap_addr = posix.mmap(null, mmap_len, posix.PROT_READ | posix.PROT_WRITE, posix.MAP_PRIVATE | posix.MAP_ANONYMOUS | MAP_GROWSDOWN, -1, 0);
+ if (mmap_addr == posix.MAP_FAILED) return error.OutOfMemory;
+ errdefer assert(posix.munmap(mmap_addr, mmap_len) == 0);
+
+ const thread_ptr = @alignCast(@alignOf(Thread), @intToPtr(*Thread, mmap_addr + thread_start_offset));
+ thread_ptr.data.mmap_addr = mmap_addr;
+ thread_ptr.data.mmap_len = mmap_len;
- var stack_end: usize = stack_addr + mmap_len;
var arg: usize = undefined;
if (@sizeOf(Context) != 0) {
- stack_end -= @sizeOf(Context);
- stack_end -= stack_end % @alignOf(Context);
- assert(stack_end >= stack_addr);
- const context_ptr = @alignCast(@alignOf(Context), @intToPtr(*Context, stack_end));
+ arg = mmap_addr + context_start_offset;
+ const context_ptr = @alignCast(@alignOf(Context), @intToPtr(*Context, arg));
context_ptr.* = context;
- arg = stack_end;
}
- stack_end -= @sizeOf(Thread);
- stack_end -= stack_end % @alignOf(Thread);
- assert(stack_end >= stack_addr);
- const thread_ptr = @alignCast(@alignOf(Thread), @intToPtr(*Thread, stack_end));
-
- thread_ptr.data.stack_addr = stack_addr;
- thread_ptr.data.stack_len = mmap_len;
-
- if (builtin.os == builtin.Os.windows) {
- // use windows API directly
- @compileError("TODO support spawnThread for Windows");
- } else if (Thread.use_pthreads) {
+ if (Thread.use_pthreads) {
// use pthreads
var attr: c.pthread_attr_t = undefined;
if (c.pthread_attr_init(&attr) != 0) return SpawnThreadError.SystemResources;
defer assert(c.pthread_attr_destroy(&attr) == 0);
- // align to page
- stack_end -= stack_end % os.page_size;
- assert(c.pthread_attr_setstack(&attr, @intToPtr(*c_void, stack_addr), stack_end - stack_addr) == 0);
+ assert(c.pthread_attr_setstack(&attr, @intToPtr(*c_void, mmap_addr), stack_end_offset) == 0);
const err = c.pthread_create(&thread_ptr.data.handle, &attr, MainFuncs.posixThreadMain, @intToPtr(*c_void, arg));
switch (err) {
@@ -3143,10 +3149,17 @@ pub fn spawnThread(context: var, comptime startFn: var) SpawnThreadError!*Thread
else => return unexpectedErrorPosix(@intCast(usize, err)),
}
} else if (builtin.os == builtin.Os.linux) {
- // use linux API directly. TODO use posix.CLONE_SETTLS and initialize thread local storage correctly
- const flags = posix.CLONE_VM | posix.CLONE_FS | posix.CLONE_FILES | posix.CLONE_SIGHAND | posix.CLONE_THREAD | posix.CLONE_SYSVSEM | posix.CLONE_PARENT_SETTID | posix.CLONE_CHILD_CLEARTID | posix.CLONE_DETACHED;
- const newtls: usize = 0;
- const rc = posix.clone(MainFuncs.linuxThreadMain, stack_end, flags, arg, &thread_ptr.data.handle, newtls, &thread_ptr.data.handle);
+ var flags: u32 = posix.CLONE_VM | posix.CLONE_FS | posix.CLONE_FILES | posix.CLONE_SIGHAND |
+ posix.CLONE_THREAD | posix.CLONE_SYSVSEM | posix.CLONE_PARENT_SETTID | posix.CLONE_CHILD_CLEARTID |
+ posix.CLONE_DETACHED;
+ var newtls: usize = undefined;
+ if (startup.linux_tls_phdr) |tls_phdr| {
+ @memcpy(@intToPtr([*]u8, mmap_addr + tls_start_offset), startup.linux_tls_img_src, tls_phdr.p_filesz);
+ thread_ptr.data.tls_end_addr = mmap_addr + mmap_len;
+ newtls = @ptrToInt(&thread_ptr.data.tls_end_addr);
+ flags |= posix.CLONE_SETTLS;
+ }
+ const rc = posix.clone(MainFuncs.linuxThreadMain, mmap_addr + stack_end_offset, flags, arg, &thread_ptr.data.handle, newtls, &thread_ptr.data.handle);
const err = posix.getErrno(rc);
switch (err) {
0 => return thread_ptr,
std/os/startup.zig
@@ -0,0 +1,26 @@
+// This file contains global variables that are initialized on startup from
+// std/special/bootstrap.zig. There are a few things to be aware of here.
+//
+// First, when building an object or library, and no entry point is defined
+// (such as pub fn main), std/special/bootstrap.zig is not included in the
+// compilation. And so these global variables will remain set to the values
+// you see here.
+//
+// Second, when using `zig test` to test the standard library, note that
+// `zig test` is self-hosted. This means that it uses std/special/bootstrap.zig
+// and an @import("std") from the install directory, which is distinct from
+// the standard library files that we are directly testing with `zig test`.
+// This means that these global variables would not get set. So the workaround
+// here is that references to these globals from the standard library must
+// use `@import("std").startup` rather than
+// `@import("path/to/std/index.zig").startup` (and rather than the file path of
+// this file directly). We also put "std" as a reference to itself in the
+// standard library package so that this can work.
+
+const std = @import("../index.zig");
+
+pub var linux_tls_phdr: ?*std.elf.Phdr = null;
+pub var linux_tls_img_src: [*]const u8 = undefined; // defined when linux_tls_phdr is non-null
+pub var linux_elf_aux_maybe: ?[*]std.elf.Auxv = null;
+pub var posix_environ_raw: [][*]u8 = undefined;
+pub var posix_argv_raw: [][*]u8 = undefined;
std/os/test.zig
@@ -105,3 +105,19 @@ test "AtomicFile" {
try os.deleteFile(test_out_file);
}
+
+test "thread local storage" {
+ if (builtin.single_threaded) return error.SkipZigTest;
+ const thread1 = try std.os.spawnThread({}, testTls);
+ const thread2 = try std.os.spawnThread({}, testTls);
+ testTls({});
+ thread1.wait();
+ thread2.wait();
+}
+
+threadlocal var x: i32 = 1234;
+fn testTls(context: void) void {
+ if (x != 1234) @panic("bad start value");
+ x += 1;
+ if (x != 1235) @panic("bad end value");
+}
std/special/bootstrap.zig
@@ -4,6 +4,7 @@
const root = @import("@root");
const std = @import("std");
const builtin = @import("builtin");
+const assert = std.debug.assert;
var argc_ptr: [*]usize = undefined;
@@ -61,9 +62,23 @@ fn posixCallMainAndExit() noreturn {
while (envp_optional[envp_count]) |_| : (envp_count += 1) {}
const envp = @ptrCast([*][*]u8, envp_optional)[0..envp_count];
if (builtin.os == builtin.Os.linux) {
- const auxv = @ptrCast([*]usize, envp.ptr + envp_count + 1);
- std.os.linux_elf_aux_maybe = @ptrCast([*]std.elf.Auxv, auxv);
- std.debug.assert(std.os.linuxGetAuxVal(std.elf.AT_PAGESZ) == std.os.page_size);
+ // Scan auxiliary vector.
+ const auxv = @ptrCast([*]std.elf.Auxv, envp.ptr + envp_count + 1);
+ std.startup.linux_elf_aux_maybe = auxv;
+ var i: usize = 0;
+ var at_phdr: usize = 0;
+ var at_phnum: usize = 0;
+ var at_phent: usize = 0;
+ while (auxv[i].a_un.a_val != 0) : (i += 1) {
+ switch (auxv[i].a_type) {
+ std.elf.AT_PAGESZ => assert(auxv[i].a_un.a_val == std.os.page_size),
+ std.elf.AT_PHDR => at_phdr = auxv[i].a_un.a_val,
+ std.elf.AT_PHNUM => at_phnum = auxv[i].a_un.a_val,
+ std.elf.AT_PHENT => at_phent = auxv[i].a_un.a_val,
+ else => {},
+ }
+ }
+ if (!builtin.single_threaded) linuxInitializeThreadLocalStorage(at_phdr, at_phnum, at_phent);
}
std.os.posix.exit(callMainWithArgs(argc, argv, envp));
@@ -72,8 +87,8 @@ fn posixCallMainAndExit() noreturn {
// This is marked inline because for some reason LLVM in release mode fails to inline it,
// and we want fewer call frames in stack traces.
inline fn callMainWithArgs(argc: usize, argv: [*][*]u8, envp: [][*]u8) u8 {
- std.os.ArgIteratorPosix.raw = argv[0..argc];
- std.os.posix_environ_raw = envp;
+ std.startup.posix_argv_raw = argv[0..argc];
+ std.startup.posix_environ_raw = envp;
return callMain();
}
@@ -116,3 +131,41 @@ inline fn callMain() u8 {
else => @compileError("expected return type of main to be 'u8', 'noreturn', 'void', or '!void'"),
}
}
+
+var tls_end_addr: usize = undefined;
+const main_thread_tls_align = 32;
+var main_thread_tls_bytes: [64]u8 align(main_thread_tls_align) = [1]u8{0} ** 64;
+
+fn linuxInitializeThreadLocalStorage(at_phdr: usize, at_phnum: usize, at_phent: usize) void {
+ var phdr_addr = at_phdr;
+ var n = at_phnum;
+ var base: usize = 0;
+ while (n != 0) : ({n -= 1; phdr_addr += at_phent;}) {
+ const phdr = @intToPtr(*std.elf.Phdr, phdr_addr);
+ // TODO look for PT_DYNAMIC when we have https://github.com/ziglang/zig/issues/1917
+ switch (phdr.p_type) {
+ std.elf.PT_PHDR => base = at_phdr - phdr.p_vaddr,
+ std.elf.PT_TLS => std.startup.linux_tls_phdr = phdr,
+ else => continue,
+ }
+ }
+ const tls_phdr = std.startup.linux_tls_phdr orelse return;
+ std.startup.linux_tls_img_src = @intToPtr([*]const u8, base + tls_phdr.p_vaddr);
+ assert(main_thread_tls_bytes.len >= tls_phdr.p_memsz); // not enough preallocated Thread Local Storage
+ assert(main_thread_tls_align >= tls_phdr.p_align); // preallocated Thread Local Storage not aligned enough
+ @memcpy(&main_thread_tls_bytes, std.startup.linux_tls_img_src, tls_phdr.p_filesz);
+ tls_end_addr = @ptrToInt(&main_thread_tls_bytes) + tls_phdr.p_memsz;
+ linuxSetThreadArea(@ptrToInt(&tls_end_addr));
+}
+
+fn linuxSetThreadArea(addr: usize) void {
+ switch (builtin.arch) {
+ builtin.Arch.x86_64 => {
+ const ARCH_SET_FS = 0x1002;
+ const rc = std.os.linux.syscall2(std.os.linux.SYS_arch_prctl, ARCH_SET_FS, addr);
+ // acrh_prctl is documented to never fail
+ assert(rc == 0);
+ },
+ else => @compileError("Unsupported architecture"),
+ }
+}
std/heap.zig
@@ -106,9 +106,7 @@ pub const DirectAllocator = struct {
};
const ptr = os.windows.HeapAlloc(heap_handle, 0, amt) orelse return error.OutOfMemory;
const root_addr = @ptrToInt(ptr);
- const rem = @rem(root_addr, alignment);
- const march_forward_bytes = if (rem == 0) 0 else (alignment - rem);
- const adjusted_addr = root_addr + march_forward_bytes;
+ const adjusted_addr = mem.alignForward(root_addr, alignment);
const record_addr = adjusted_addr + n;
@intToPtr(*align(1) usize, record_addr).* = root_addr;
return @intToPtr([*]u8, adjusted_addr)[0..n];
@@ -126,8 +124,7 @@ pub const DirectAllocator = struct {
const base_addr = @ptrToInt(old_mem.ptr);
const old_addr_end = base_addr + old_mem.len;
const new_addr_end = base_addr + new_size;
- const rem = @rem(new_addr_end, os.page_size);
- const new_addr_end_rounded = new_addr_end + if (rem == 0) 0 else (os.page_size - rem);
+ const new_addr_end_rounded = mem.alignForward(new_addr_end, os.page_size);
if (old_addr_end > new_addr_end_rounded) {
_ = os.posix.munmap(new_addr_end_rounded, old_addr_end - new_addr_end_rounded);
}
std/index.zig
@@ -33,8 +33,8 @@ pub const io = @import("io.zig");
pub const json = @import("json.zig");
pub const macho = @import("macho.zig");
pub const math = @import("math/index.zig");
-pub const meta = @import("meta/index.zig");
pub const mem = @import("mem.zig");
+pub const meta = @import("meta/index.zig");
pub const net = @import("net.zig");
pub const os = @import("os/index.zig");
pub const pdb = @import("pdb.zig");
@@ -45,6 +45,7 @@ pub const unicode = @import("unicode.zig");
pub const zig = @import("zig/index.zig");
pub const lazyInit = @import("lazy_init.zig").lazyInit;
+pub const startup = @import("os/startup.zig");
test "std" {
// run tests from these
std/mem.zig
@@ -1366,3 +1366,23 @@ test "std.mem.subArrayPtr" {
sub2[1] = 'X';
debug.assert(std.mem.eql(u8, a2, "abcXef"));
}
+
+/// Round an address up to the nearest aligned address
+pub fn alignForward(addr: usize, alignment: usize) usize {
+ return (addr + alignment - 1) & ~(alignment - 1);
+}
+
+test "std.mem.alignForward" {
+ debug.assertOrPanic(alignForward(1, 1) == 1);
+ debug.assertOrPanic(alignForward(2, 1) == 2);
+ debug.assertOrPanic(alignForward(1, 2) == 2);
+ debug.assertOrPanic(alignForward(2, 2) == 2);
+ debug.assertOrPanic(alignForward(3, 2) == 4);
+ debug.assertOrPanic(alignForward(4, 2) == 4);
+ debug.assertOrPanic(alignForward(7, 8) == 8);
+ debug.assertOrPanic(alignForward(8, 8) == 8);
+ debug.assertOrPanic(alignForward(9, 8) == 16);
+ debug.assertOrPanic(alignForward(15, 8) == 16);
+ debug.assertOrPanic(alignForward(16, 8) == 16);
+ debug.assertOrPanic(alignForward(17, 8) == 24);
+}
test/stage1/behavior/misc.zig
@@ -685,3 +685,11 @@ test "fn call returning scalar optional in equality expression" {
fn getNull() ?*i32 {
return null;
}
+
+test "thread local variable" {
+ const S = struct {
+ threadlocal var t: i32 = 1234;
+ };
+ S.t += 1;
+ assertOrPanic(S.t == 1235);
+}
test/compile_errors.zig
@@ -1,6 +1,25 @@
const tests = @import("tests.zig");
pub fn addCases(cases: *tests.CompileErrorContext) void {
+ cases.add(
+ "threadlocal qualifier on const",
+ \\threadlocal const x: i32 = 1234;
+ \\export fn entry() i32 {
+ \\ return x;
+ \\}
+ ,
+ ".tmp_source.zig:1:13: error: threadlocal variable cannot be constant",
+ );
+
+ cases.add(
+ "threadlocal qualifier on local variable",
+ \\export fn entry() void {
+ \\ threadlocal var x: i32 = 1234;
+ \\}
+ ,
+ ".tmp_source.zig:2:5: error: function-local variable 'x' cannot be threadlocal",
+ );
+
cases.add(
"@bitCast same size but bit count mismatch",
\\export fn entry(byte: u8) void {
CMakeLists.txt
@@ -587,6 +587,7 @@ set(ZIG_STD_FILES
"os/linux/vdso.zig"
"os/linux/x86_64.zig"
"os/path.zig"
+ "os/startup.zig"
"os/time.zig"
"os/uefi.zig"
"os/windows/advapi32.zig"