stage2: WASM LLD linking
parent
73167e80f8
commit
ed06a78f35
|
@ -1,5 +1,4 @@
|
||||||
* MachO LLD linking
|
* MachO LLD linking
|
||||||
* WASM LLD linking
|
|
||||||
* audit the CLI options for stage2
|
* audit the CLI options for stage2
|
||||||
* audit the base cache hash
|
* audit the base cache hash
|
||||||
* On operating systems that support it, do an execve for `zig test` and `zig run` rather than child process.
|
* On operating systems that support it, do an execve for `zig test` and `zig run` rather than child process.
|
||||||
|
|
|
@ -1486,7 +1486,7 @@ pub const Target = struct {
|
||||||
|
|
||||||
/// Return whether or not the given host target is capable of executing natively executables
|
/// Return whether or not the given host target is capable of executing natively executables
|
||||||
/// of the other target.
|
/// of the other target.
|
||||||
pub fn canExecBinariesOf(host_target: std.Target, binary_target: std.Target) bool {
|
pub fn canExecBinariesOf(host_target: Target, binary_target: Target) bool {
|
||||||
if (host_target.os.tag != binary_target.os.tag)
|
if (host_target.os.tag != binary_target.os.tag)
|
||||||
return false;
|
return false;
|
||||||
|
|
||||||
|
|
|
@ -2418,7 +2418,7 @@ fn buildStaticLibFromZig(comp: *Compilation, src_basename: []const u8, out: *?CR
|
||||||
const bin_basename = try std.zig.binNameAlloc(comp.gpa, .{
|
const bin_basename = try std.zig.binNameAlloc(comp.gpa, .{
|
||||||
.root_name = root_name,
|
.root_name = root_name,
|
||||||
.target = target,
|
.target = target,
|
||||||
.output_mode = .Lib,
|
.output_mode = .Obj,
|
||||||
});
|
});
|
||||||
defer comp.gpa.free(bin_basename);
|
defer comp.gpa.free(bin_basename);
|
||||||
|
|
||||||
|
@ -2441,7 +2441,7 @@ fn buildStaticLibFromZig(comp: *Compilation, src_basename: []const u8, out: *?CR
|
||||||
.target = target,
|
.target = target,
|
||||||
.root_name = root_name,
|
.root_name = root_name,
|
||||||
.root_pkg = &root_pkg,
|
.root_pkg = &root_pkg,
|
||||||
.output_mode = .Lib,
|
.output_mode = .Obj,
|
||||||
.rand = comp.rand,
|
.rand = comp.rand,
|
||||||
.libc_installation = comp.bin_file.options.libc_installation,
|
.libc_installation = comp.bin_file.options.libc_installation,
|
||||||
.emit_bin = emit_bin,
|
.emit_bin = emit_bin,
|
||||||
|
|
|
@ -1,10 +1,12 @@
|
||||||
const Wasm = @This();
|
const Wasm = @This();
|
||||||
|
|
||||||
const std = @import("std");
|
const std = @import("std");
|
||||||
|
const mem = std.mem;
|
||||||
const Allocator = std.mem.Allocator;
|
const Allocator = std.mem.Allocator;
|
||||||
const assert = std.debug.assert;
|
const assert = std.debug.assert;
|
||||||
const fs = std.fs;
|
const fs = std.fs;
|
||||||
const leb = std.debug.leb;
|
const leb = std.debug.leb;
|
||||||
|
const log = std.log.scoped(.link);
|
||||||
|
|
||||||
const Module = @import("../Module.zig");
|
const Module = @import("../Module.zig");
|
||||||
const Compilation = @import("../Compilation.zig");
|
const Compilation = @import("../Compilation.zig");
|
||||||
|
@ -12,6 +14,7 @@ const codegen = @import("../codegen/wasm.zig");
|
||||||
const link = @import("../link.zig");
|
const link = @import("../link.zig");
|
||||||
const trace = @import("../tracy.zig").trace;
|
const trace = @import("../tracy.zig").trace;
|
||||||
const build_options = @import("build_options");
|
const build_options = @import("build_options");
|
||||||
|
const Cache = @import("../Cache.zig");
|
||||||
|
|
||||||
/// Various magic numbers defined by the wasm spec
|
/// Various magic numbers defined by the wasm spec
|
||||||
const spec = struct {
|
const spec = struct {
|
||||||
|
@ -137,7 +140,7 @@ pub fn freeDecl(self: *Wasm, decl: *Module.Decl) void {
|
||||||
|
|
||||||
pub fn flush(self: *Wasm, comp: *Compilation) !void {
|
pub fn flush(self: *Wasm, comp: *Compilation) !void {
|
||||||
if (build_options.have_llvm and self.base.options.use_lld) {
|
if (build_options.have_llvm and self.base.options.use_lld) {
|
||||||
return error.WasmLinkingWithLLDUnimplemented;
|
return self.linkWithLLD(comp);
|
||||||
} else {
|
} else {
|
||||||
return self.flushModule(comp);
|
return self.flushModule(comp);
|
||||||
}
|
}
|
||||||
|
@ -248,6 +251,211 @@ pub fn flushModule(self: *Wasm, comp: *Compilation) !void {
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
fn linkWithLLD(self: *Wasm, comp: *Compilation) !void {
|
||||||
|
const tracy = trace(@src());
|
||||||
|
defer tracy.end();
|
||||||
|
|
||||||
|
var arena_allocator = std.heap.ArenaAllocator.init(self.base.allocator);
|
||||||
|
defer arena_allocator.deinit();
|
||||||
|
const arena = &arena_allocator.allocator;
|
||||||
|
|
||||||
|
const directory = self.base.options.emit.?.directory; // Just an alias to make it shorter to type.
|
||||||
|
|
||||||
|
// If there is no Zig code to compile, then we should skip flushing the output file because it
|
||||||
|
// will not be part of the linker line anyway.
|
||||||
|
const module_obj_path: ?[]const u8 = if (self.base.options.module) |module| blk: {
|
||||||
|
const use_stage1 = build_options.is_stage1 and self.base.options.use_llvm;
|
||||||
|
if (use_stage1) {
|
||||||
|
const obj_basename = try std.zig.binNameAlloc(arena, .{
|
||||||
|
.root_name = self.base.options.root_name,
|
||||||
|
.target = self.base.options.target,
|
||||||
|
.output_mode = .Obj,
|
||||||
|
});
|
||||||
|
const o_directory = self.base.options.module.?.zig_cache_artifact_directory;
|
||||||
|
const full_obj_path = try o_directory.join(arena, &[_][]const u8{obj_basename});
|
||||||
|
break :blk full_obj_path;
|
||||||
|
}
|
||||||
|
|
||||||
|
try self.flushModule(comp);
|
||||||
|
const obj_basename = self.base.intermediary_basename.?;
|
||||||
|
const full_obj_path = try directory.join(arena, &[_][]const u8{obj_basename});
|
||||||
|
break :blk full_obj_path;
|
||||||
|
} else null;
|
||||||
|
|
||||||
|
const target = self.base.options.target;
|
||||||
|
|
||||||
|
const id_symlink_basename = "lld.id";
|
||||||
|
|
||||||
|
var man: Cache.Manifest = undefined;
|
||||||
|
defer if (!self.base.options.disable_lld_caching) man.deinit();
|
||||||
|
|
||||||
|
var digest: [Cache.hex_digest_len]u8 = undefined;
|
||||||
|
|
||||||
|
if (!self.base.options.disable_lld_caching) {
|
||||||
|
man = comp.cache_parent.obtain();
|
||||||
|
|
||||||
|
// We are about to obtain this lock, so here we give other processes a chance first.
|
||||||
|
self.base.releaseLock();
|
||||||
|
|
||||||
|
try man.addListOfFiles(self.base.options.objects);
|
||||||
|
for (comp.c_object_table.items()) |entry| {
|
||||||
|
_ = try man.addFile(entry.key.status.success.object_path, null);
|
||||||
|
}
|
||||||
|
try man.addOptionalFile(module_obj_path);
|
||||||
|
man.hash.addOptional(self.base.options.stack_size_override);
|
||||||
|
man.hash.addListOfBytes(self.base.options.extra_lld_args);
|
||||||
|
|
||||||
|
// We don't actually care whether it's a cache hit or miss; we just need the digest and the lock.
|
||||||
|
_ = try man.hit();
|
||||||
|
digest = man.final();
|
||||||
|
|
||||||
|
var prev_digest_buf: [digest.len]u8 = undefined;
|
||||||
|
const prev_digest: []u8 = directory.handle.readLink(id_symlink_basename, &prev_digest_buf) catch |err| blk: {
|
||||||
|
log.debug("WASM LLD new_digest={} readlink error: {}", .{ digest, @errorName(err) });
|
||||||
|
// Handle this as a cache miss.
|
||||||
|
break :blk prev_digest_buf[0..0];
|
||||||
|
};
|
||||||
|
if (mem.eql(u8, prev_digest, &digest)) {
|
||||||
|
log.debug("WASM LLD digest={} match - skipping invocation", .{digest});
|
||||||
|
// Hot diggity dog! The output binary is already there.
|
||||||
|
self.base.lock = man.toOwnedLock();
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
log.debug("WASM LLD prev_digest={} new_digest={}", .{ prev_digest, digest });
|
||||||
|
|
||||||
|
// We are about to change the output file to be different, so we invalidate the build hash now.
|
||||||
|
directory.handle.deleteFile(id_symlink_basename) catch |err| switch (err) {
|
||||||
|
error.FileNotFound => {},
|
||||||
|
else => |e| return e,
|
||||||
|
};
|
||||||
|
}
|
||||||
|
|
||||||
|
const is_obj = self.base.options.output_mode == .Obj;
|
||||||
|
|
||||||
|
// Create an LLD command line and invoke it.
|
||||||
|
var argv = std.ArrayList([]const u8).init(self.base.allocator);
|
||||||
|
defer argv.deinit();
|
||||||
|
// Even though we're calling LLD as a library it thinks the first argument is its own exe name.
|
||||||
|
try argv.append("lld");
|
||||||
|
if (is_obj) {
|
||||||
|
try argv.append("-r");
|
||||||
|
}
|
||||||
|
|
||||||
|
try argv.append("-error-limit=0");
|
||||||
|
|
||||||
|
if (self.base.options.output_mode == .Exe) {
|
||||||
|
// Increase the default stack size to a more reasonable value of 1MB instead of
|
||||||
|
// the default of 1 Wasm page being 64KB, unless overriden by the user.
|
||||||
|
try argv.append("-z");
|
||||||
|
const stack_size = self.base.options.stack_size_override orelse 1048576;
|
||||||
|
const arg = try std.fmt.allocPrint(arena, "stack-size={d}", .{stack_size});
|
||||||
|
try argv.append(arg);
|
||||||
|
|
||||||
|
// Put stack before globals so that stack overflow results in segfault immediately
|
||||||
|
// before corrupting globals. See https://github.com/ziglang/zig/issues/4496
|
||||||
|
try argv.append("--stack-first");
|
||||||
|
} else {
|
||||||
|
try argv.append("--no-entry"); // So lld doesn't look for _start.
|
||||||
|
try argv.append("--export-all");
|
||||||
|
}
|
||||||
|
try argv.appendSlice(&[_][]const u8{
|
||||||
|
"--allow-undefined",
|
||||||
|
"-o",
|
||||||
|
try directory.join(arena, &[_][]const u8{self.base.options.emit.?.sub_path}),
|
||||||
|
});
|
||||||
|
|
||||||
|
// Positional arguments to the linker such as object files.
|
||||||
|
try argv.appendSlice(self.base.options.objects);
|
||||||
|
|
||||||
|
for (comp.c_object_table.items()) |entry| {
|
||||||
|
try argv.append(entry.key.status.success.object_path);
|
||||||
|
}
|
||||||
|
if (module_obj_path) |p| {
|
||||||
|
try argv.append(p);
|
||||||
|
}
|
||||||
|
|
||||||
|
if (self.base.options.output_mode == .Exe and !self.base.options.is_compiler_rt_or_libc) {
|
||||||
|
if (!self.base.options.link_libc) {
|
||||||
|
try argv.append(comp.libc_static_lib.?.full_object_path);
|
||||||
|
}
|
||||||
|
try argv.append(comp.compiler_rt_static_lib.?.full_object_path);
|
||||||
|
}
|
||||||
|
|
||||||
|
if (self.base.options.verbose_link) {
|
||||||
|
Compilation.dump_argv(argv.items);
|
||||||
|
}
|
||||||
|
|
||||||
|
// TODO allocSentinel crashed stage1 so this is working around it.
|
||||||
|
const new_argv_with_sentinel = try arena.alloc(?[*:0]const u8, argv.items.len + 1);
|
||||||
|
new_argv_with_sentinel[argv.items.len] = null;
|
||||||
|
const new_argv = new_argv_with_sentinel[0..argv.items.len :null];
|
||||||
|
for (argv.items) |arg, i| {
|
||||||
|
new_argv[i] = try arena.dupeZ(u8, arg);
|
||||||
|
}
|
||||||
|
|
||||||
|
var stderr_context: LLDContext = .{
|
||||||
|
.wasm = self,
|
||||||
|
.data = std.ArrayList(u8).init(self.base.allocator),
|
||||||
|
};
|
||||||
|
defer stderr_context.data.deinit();
|
||||||
|
var stdout_context: LLDContext = .{
|
||||||
|
.wasm = self,
|
||||||
|
.data = std.ArrayList(u8).init(self.base.allocator),
|
||||||
|
};
|
||||||
|
defer stdout_context.data.deinit();
|
||||||
|
const llvm = @import("../llvm.zig");
|
||||||
|
const ok = llvm.Link(
|
||||||
|
.Wasm,
|
||||||
|
new_argv.ptr,
|
||||||
|
new_argv.len,
|
||||||
|
append_diagnostic,
|
||||||
|
@ptrToInt(&stdout_context),
|
||||||
|
@ptrToInt(&stderr_context),
|
||||||
|
);
|
||||||
|
if (stderr_context.oom or stdout_context.oom) return error.OutOfMemory;
|
||||||
|
if (stdout_context.data.items.len != 0) {
|
||||||
|
std.log.warn("unexpected LLD stdout: {}", .{stdout_context.data.items});
|
||||||
|
}
|
||||||
|
if (!ok) {
|
||||||
|
// TODO parse this output and surface with the Compilation API rather than
|
||||||
|
// directly outputting to stderr here.
|
||||||
|
std.debug.print("{}", .{stderr_context.data.items});
|
||||||
|
return error.LLDReportedFailure;
|
||||||
|
}
|
||||||
|
if (stderr_context.data.items.len != 0) {
|
||||||
|
std.log.warn("unexpected LLD stderr: {}", .{stderr_context.data.items});
|
||||||
|
}
|
||||||
|
|
||||||
|
if (!self.base.options.disable_lld_caching) {
|
||||||
|
// Update the dangling symlink with the digest. If it fails we can continue; it only
|
||||||
|
// means that the next invocation will have an unnecessary cache miss.
|
||||||
|
directory.handle.symLink(&digest, id_symlink_basename, .{}) catch |err| {
|
||||||
|
std.log.warn("failed to save linking hash digest symlink: {}", .{@errorName(err)});
|
||||||
|
};
|
||||||
|
// Again failure here only means an unnecessary cache miss.
|
||||||
|
man.writeManifest() catch |err| {
|
||||||
|
std.log.warn("failed to write cache manifest when linking: {}", .{@errorName(err)});
|
||||||
|
};
|
||||||
|
// We hang on to this lock so that the output file path can be used without
|
||||||
|
// other processes clobbering it.
|
||||||
|
self.base.lock = man.toOwnedLock();
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
const LLDContext = struct {
|
||||||
|
data: std.ArrayList(u8),
|
||||||
|
wasm: *Wasm,
|
||||||
|
oom: bool = false,
|
||||||
|
};
|
||||||
|
|
||||||
|
fn append_diagnostic(context: usize, ptr: [*]const u8, len: usize) callconv(.C) void {
|
||||||
|
const lld_context = @intToPtr(*LLDContext, context);
|
||||||
|
const msg = ptr[0..len];
|
||||||
|
lld_context.data.appendSlice(msg) catch |err| switch (err) {
|
||||||
|
error.OutOfMemory => lld_context.oom = true,
|
||||||
|
};
|
||||||
|
}
|
||||||
|
|
||||||
/// Get the current index of a given Decl in the function list
|
/// Get the current index of a given Decl in the function list
|
||||||
/// TODO: we could maintain a hash map to potentially make this
|
/// TODO: we could maintain a hash map to potentially make this
|
||||||
fn getFuncidx(self: Wasm, decl: *Module.Decl) ?u32 {
|
fn getFuncidx(self: Wasm, decl: *Module.Decl) ?u32 {
|
||||||
|
|
Loading…
Reference in New Issue