authorgravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2021-03-12 17:58:54+01:00
committergravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2021-03-17 19:59:13+01:00
logac0c669473b20a1fdcb818b92381d5ac5d70b64e
treede811065ccbebb97e11e8d390522678711588120
parentde209afbba0984c66fc5c9d379192edec87f0681

zld: add/fix more issues

* fix debug info for static archives * allow handling of empty object files * fix some relocs for GOT loads

3 files changed, 55 insertions(+), 9 deletions(-)

src/link/MachO/Archive.zig+6-2
......@@ -202,13 +202,17 @@ fn readObject(self: *Archive, arch: std.Target.Cpu.Arch, ar_name: []const u8, re
202202 var object = Object{
203203 .allocator = self.allocator,
204204 .name = object_name,
205 .ar_name = try mem.dupe(self.allocator, u8, ar_name),
205206 .file = new_file,
206207 .header = header,
207208 };
208209
209210 try object.readLoadCommands(reader, .{ .offset = offset });
210 try object.readSymtab();
211 try object.readStrtab();
211
212 if (object.symtab_cmd.index != null) {
213 try object.readSymtab();
214 try object.readStrtab();
215 }
212216
213217 if (object.data_in_code_cmd_index != null) try object.readDataInCode();
214218
src/link/MachO/Object.zig+9-2
......@@ -16,6 +16,7 @@ usingnamespace @import("commands.zig");
1616allocator: *Allocator,
1717file: fs.File,
1818name: []u8,
19ar_name: ?[]u8 = null,
1920
2021header: macho.mach_header_64,
2122
......@@ -49,6 +50,9 @@ pub fn deinit(self: *Object) void {
4950 self.strtab.deinit(self.allocator);
5051 self.data_in_code_entries.deinit(self.allocator);
5152 self.allocator.free(self.name);
53 if (self.ar_name) |v| {
54 self.allocator.free(v);
55 }
5256 self.file.close();
5357}
5458
......@@ -85,8 +89,11 @@ pub fn initFromFile(allocator: *Allocator, arch: std.Target.Cpu.Arch, name: []co
8589 };
8690
8791 try self.readLoadCommands(reader, .{});
88 try self.readSymtab();
89 try self.readStrtab();
92
93 if (self.symtab_cmd_index != null) {
94 try self.readSymtab();
95 try self.readStrtab();
96 }
9097
9198 if (self.data_in_code_cmd_index != null) try self.readDataInCode();
9299
src/link/MachO/Zld.zig+40-5
......@@ -767,7 +767,9 @@ fn resolveImports(self: *Zld) !void {
767767 mem.eql(u8, sym_name, "___stderrp") or
768768 mem.eql(u8, sym_name, "___stdinp") or
769769 mem.eql(u8, sym_name, "___stack_chk_guard") or
770 mem.eql(u8, sym_name, "_environ"))
770 mem.eql(u8, sym_name, "_environ") or
771 mem.eql(u8, sym_name, "__DefaultRuneLocale") or
772 mem.eql(u8, sym_name, "_mach_task_self_"))
771773 {
772774 log.debug("writing nonlazy symbol '{s}'", .{sym_name});
773775 const index = @intCast(u32, self.nonlazy_imports.items().len);
......@@ -1192,6 +1194,8 @@ fn writeStubInStubHelper(self: *Zld, index: u32) !void {
11921194fn resolveSymbols(self: *Zld) !void {
11931195 for (self.objects.items) |object, object_id| {
11941196 const seg = object.load_commands.items[object.segment_cmd_index.?].Segment;
1197 log.debug("\n\n", .{});
1198 log.debug("resolving symbols in {s}", .{object.name});
11951199
11961200 for (object.symtab.items) |sym| {
11971201 if (isImport(&sym)) continue;
......@@ -1219,8 +1223,10 @@ fn resolveSymbols(self: *Zld) !void {
12191223 if (tt == .Global) {
12201224 for (locs.entry.value.items) |ss| {
12211225 if (ss.tt == .Global) {
1222 log.err("symbol '{s}' defined multiple times", .{sym_name});
1223 return error.MultipleSymbolDefinitions;
1226 log.debug("symbol already defined '{s}'", .{sym_name});
1227 continue;
1228 // log.err("symbol '{s}' defined multiple times: {}", .{ sym_name, sym });
1229 // return error.MultipleSymbolDefinitions;
12241230 }
12251231 }
12261232 }
......@@ -1589,8 +1595,28 @@ fn doRelocs(self: *Zld) !void {
15891595 ),
15901596 inst,
15911597 );
1598
15921599 const ta = if (addend) |a| target_addr + a else target_addr;
15931600 const narrowed = @truncate(u12, ta);
1601 log.debug(" | narrowed 0x{x}", .{narrowed});
1602 log.debug(" | parsed.size 0x{x}", .{parsed.size});
1603
1604 if (rel_type == .ARM64_RELOC_GOT_LOAD_PAGEOFF12) blk: {
1605 const data_const_seg = self.load_commands.items[self.data_const_segment_cmd_index.?].Segment;
1606 const got = data_const_seg.sections.items[self.got_section_index.?];
1607 if (got.addr <= target_addr and target_addr < got.addr + got.size) break :blk;
1608
1609 log.debug(" | rewriting to add", .{});
1610 mem.writeIntLittle(u32, inst, aarch64.Instruction.add(
1611 @intToEnum(aarch64.Register, parsed.rt),
1612 @intToEnum(aarch64.Register, parsed.rn),
1613 narrowed,
1614 false,
1615 ).toU32());
1616 addend = null;
1617 continue;
1618 }
1619
15941620 const offset: u12 = blk: {
15951621 if (parsed.size == 0) {
15961622 if (parsed.v == 1) {
......@@ -2628,8 +2654,16 @@ fn writeDebugInfo(self: *Zld) !void {
26282654 });
26292655 // Path to object file with debug info
26302656 var buffer: [std.fs.MAX_PATH_BYTES]u8 = undefined;
2631 const path = object.name;
2632 const full_path = try std.os.realpath(path, &buffer);
2657 const full_path = blk: {
2658 if (object.ar_name) |prefix| {
2659 const path = try std.os.realpath(prefix, &buffer);
2660 break :blk try std.fmt.allocPrint(self.allocator, "{s}({s})", .{ path, object.name });
2661 } else {
2662 const path = try std.os.realpath(object.name, &buffer);
2663 break :blk try mem.dupe(self.allocator, u8, path);
2664 }
2665 };
2666 defer self.allocator.free(full_path);
26332667 const stat = try object.file.stat();
26342668 const mtime = @intCast(u64, @divFloor(stat.mtime, 1_000_000_000));
26352669 try stabs.append(.{
......@@ -2640,6 +2674,7 @@ fn writeDebugInfo(self: *Zld) !void {
26402674 .n_value = mtime,
26412675 });
26422676 }
2677 log.debug("analyzing debug info in '{s}'", .{object.name});
26432678
26442679 for (object.symtab.items) |source_sym| {
26452680 const symname = object.getString(source_sym.n_strx);