Commit b9fa80e588
Changed files (3)
src
link
src/link/MachO/bind.zig
@@ -0,0 +1,145 @@
+const std = @import("std");
+const leb = std.leb;
+const macho = std.macho;
+
+pub const Pointer = struct {
+ offset: u64,
+ segment_id: u16,
+ dylib_ordinal: ?i64 = null,
+ name: ?[]const u8 = null,
+};
+
+pub fn pointerCmp(context: void, a: Pointer, b: Pointer) bool {
+ if (a.segment_id < b.segment_id) return true;
+ if (a.segment_id == b.segment_id) {
+ return a.offset < b.offset;
+ }
+ return false;
+}
+
+pub fn rebaseInfoSize(pointers: []const Pointer) !u64 {
+ var stream = std.io.countingWriter(std.io.null_writer);
+ var writer = stream.writer();
+ var size: u64 = 0;
+
+ for (pointers) |pointer| {
+ size += 2;
+ try leb.writeILEB128(writer, pointer.offset);
+ size += 1;
+ }
+
+ size += 1 + stream.bytes_written;
+ return size;
+}
+
+pub fn writeRebaseInfo(pointers: []const Pointer, writer: anytype) !void {
+ for (pointers) |pointer| {
+ try writer.writeByte(macho.REBASE_OPCODE_SET_TYPE_IMM | @truncate(u4, macho.REBASE_TYPE_POINTER));
+ try writer.writeByte(macho.REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, pointer.segment_id));
+
+ try leb.writeILEB128(writer, pointer.offset);
+ try writer.writeByte(macho.REBASE_OPCODE_DO_REBASE_IMM_TIMES | @truncate(u4, 1));
+ }
+ try writer.writeByte(macho.REBASE_OPCODE_DONE);
+}
+
+pub fn bindInfoSize(pointers: []const Pointer) !u64 {
+ var stream = std.io.countingWriter(std.io.null_writer);
+ var writer = stream.writer();
+ var size: u64 = 0;
+
+ for (pointers) |pointer| {
+ size += 1;
+ if (pointer.dylib_ordinal.? > 15) {
+ try leb.writeULEB128(writer, @bitCast(u64, pointer.dylib_ordinal.?));
+ }
+ size += 1;
+
+ size += 1;
+ size += pointer.name.?.len;
+ size += 1;
+
+ size += 1;
+
+ try leb.writeILEB128(writer, pointer.offset);
+ size += 1;
+ }
+
+ size += stream.bytes_written + 1;
+ return size;
+}
+
+pub fn writeBindInfo(pointers: []const Pointer, writer: anytype) !void {
+ for (pointers) |pointer| {
+ if (pointer.dylib_ordinal.? > 15) {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB);
+ try leb.writeULEB128(writer, @bitCast(u64, pointer.dylib_ordinal.?));
+ } else if (pointer.dylib_ordinal.? > 0) {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_IMM | @truncate(u4, @bitCast(u64, pointer.dylib_ordinal.?)));
+ } else {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_SPECIAL_IMM | @truncate(u4, @bitCast(u64, pointer.dylib_ordinal.?)));
+ }
+ try writer.writeByte(macho.BIND_OPCODE_SET_TYPE_IMM | @truncate(u4, macho.BIND_TYPE_POINTER));
+
+ try writer.writeByte(macho.BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM); // TODO Sometimes we might want to add flags.
+ try writer.writeAll(pointer.name.?);
+ try writer.writeByte(0);
+
+ try writer.writeByte(macho.BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, pointer.segment_id));
+
+ try leb.writeILEB128(writer, pointer.offset);
+ try writer.writeByte(macho.BIND_OPCODE_DO_BIND);
+ }
+
+ try writer.writeByte(macho.BIND_OPCODE_DONE);
+}
+
+pub fn lazyBindInfoSize(pointers: []const Pointer) !u64 {
+ var stream = std.io.countingWriter(std.io.null_writer);
+ var writer = stream.writer();
+ var size: u64 = 0;
+
+ for (pointers) |pointer| {
+ size += 1;
+
+ try leb.writeILEB128(writer, pointer.offset);
+
+ size += 1;
+ if (pointer.dylib_ordinal.? > 15) {
+ try leb.writeULEB128(writer, @bitCast(u64, pointer.dylib_ordinal.?));
+ }
+
+ size += 1;
+ size += pointer.name.?.len;
+ size += 1;
+
+ size += 2;
+ }
+
+ size += stream.bytes_written;
+ return size;
+}
+
+pub fn writeLazyBindInfo(pointers: []const Pointer, writer: anytype) !void {
+ for (pointers) |pointer| {
+ try writer.writeByte(macho.BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, pointer.segment_id));
+
+ try leb.writeILEB128(writer, pointer.offset);
+
+ if (pointer.dylib_ordinal.? > 15) {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB);
+ try leb.writeULEB128(writer, @bitCast(u64, pointer.dylib_ordinal.?));
+ } else if (pointer.dylib_ordinal.? > 0) {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_IMM | @truncate(u4, @bitCast(u64, pointer.dylib_ordinal.?)));
+ } else {
+ try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_SPECIAL_IMM | @truncate(u4, @bitCast(u64, pointer.dylib_ordinal.?)));
+ }
+
+ try writer.writeByte(macho.BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM); // TODO Sometimes we might want to add flags.
+ try writer.writeAll(pointer.name.?);
+ try writer.writeByte(0);
+
+ try writer.writeByte(macho.BIND_OPCODE_DO_BIND);
+ try writer.writeByte(macho.BIND_OPCODE_DONE);
+ }
+}
src/link/MachO/imports.zig
@@ -1,152 +0,0 @@
-const std = @import("std");
-const leb = std.leb;
-const macho = std.macho;
-const mem = std.mem;
-
-const assert = std.debug.assert;
-const Allocator = mem.Allocator;
-
-pub const ExternSymbol = struct {
- /// MachO symbol table entry.
- inner: macho.nlist_64,
-
- /// Id of the dynamic library where the specified entries can be found.
- /// Id of 0 means self.
- /// TODO this should really be an id into the table of all defined
- /// dylibs.
- dylib_ordinal: i64 = 0,
-
- /// Id of the segment where this symbol is defined (will have its address
- /// resolved).
- segment: u16 = 0,
-
- /// Offset relative to the start address of the `segment`.
- offset: u32 = 0,
-};
-
-pub fn rebaseInfoSize(symbols: anytype) !u64 {
- var stream = std.io.countingWriter(std.io.null_writer);
- var writer = stream.writer();
- var size: u64 = 0;
-
- for (symbols) |entry| {
- size += 2;
- try leb.writeILEB128(writer, entry.value.offset);
- size += 1;
- }
-
- size += 1 + stream.bytes_written;
- return size;
-}
-
-pub fn writeRebaseInfo(symbols: anytype, writer: anytype) !void {
- for (symbols) |entry| {
- const symbol = entry.value;
- try writer.writeByte(macho.REBASE_OPCODE_SET_TYPE_IMM | @truncate(u4, macho.REBASE_TYPE_POINTER));
- try writer.writeByte(macho.REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, symbol.segment));
- try leb.writeILEB128(writer, symbol.offset);
- try writer.writeByte(macho.REBASE_OPCODE_DO_REBASE_IMM_TIMES | @truncate(u4, 1));
- }
- try writer.writeByte(macho.REBASE_OPCODE_DONE);
-}
-
-pub fn bindInfoSize(symbols: anytype) !u64 {
- var stream = std.io.countingWriter(std.io.null_writer);
- var writer = stream.writer();
- var size: u64 = 0;
-
- for (symbols) |entry| {
- const symbol = entry.value;
-
- size += 1;
- if (symbol.dylib_ordinal > 15) {
- try leb.writeULEB128(writer, @bitCast(u64, symbol.dylib_ordinal));
- }
- size += 1;
-
- size += 1;
- size += entry.key.len;
- size += 1;
-
- size += 1;
- try leb.writeILEB128(writer, symbol.offset);
- size += 2;
- }
-
- size += stream.bytes_written;
- return size;
-}
-
-pub fn writeBindInfo(symbols: anytype, writer: anytype) !void {
- for (symbols) |entry| {
- const symbol = entry.value;
-
- if (symbol.dylib_ordinal > 15) {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB);
- try leb.writeULEB128(writer, @bitCast(u64, symbol.dylib_ordinal));
- } else if (symbol.dylib_ordinal > 0) {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_IMM | @truncate(u4, @bitCast(u64, symbol.dylib_ordinal)));
- } else {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_SPECIAL_IMM | @truncate(u4, @bitCast(u64, symbol.dylib_ordinal)));
- }
- try writer.writeByte(macho.BIND_OPCODE_SET_TYPE_IMM | @truncate(u4, macho.BIND_TYPE_POINTER));
-
- try writer.writeByte(macho.BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM); // TODO Sometimes we might want to add flags.
- try writer.writeAll(entry.key);
- try writer.writeByte(0);
-
- try writer.writeByte(macho.BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, symbol.segment));
- try leb.writeILEB128(writer, symbol.offset);
- try writer.writeByte(macho.BIND_OPCODE_DO_BIND);
- try writer.writeByte(macho.BIND_OPCODE_DONE);
- }
-}
-
-pub fn lazyBindInfoSize(symbols: anytype) !u64 {
- var stream = std.io.countingWriter(std.io.null_writer);
- var writer = stream.writer();
- var size: u64 = 0;
-
- for (symbols) |entry| {
- const symbol = entry.value;
- size += 1;
- try leb.writeILEB128(writer, symbol.offset);
- size += 1;
- if (symbol.dylib_ordinal > 15) {
- try leb.writeULEB128(writer, @bitCast(u64, symbol.dylib_ordinal));
- }
-
- size += 1;
- size += entry.key.len;
- size += 1;
-
- size += 2;
- }
-
- size += stream.bytes_written;
- return size;
-}
-
-pub fn writeLazyBindInfo(symbols: anytype, writer: anytype) !void {
- for (symbols) |entry| {
- const symbol = entry.value;
- try writer.writeByte(macho.BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB | @truncate(u4, symbol.segment));
- try leb.writeILEB128(writer, symbol.offset);
-
- if (symbol.dylib_ordinal > 15) {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB);
- try leb.writeULEB128(writer, @bitCast(u64, symbol.dylib_ordinal));
- } else if (symbol.dylib_ordinal > 0) {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_ORDINAL_IMM | @truncate(u4, @bitCast(u64, symbol.dylib_ordinal)));
- } else {
- try writer.writeByte(macho.BIND_OPCODE_SET_DYLIB_SPECIAL_IMM | @truncate(u4, @bitCast(u64, symbol.dylib_ordinal)));
- }
-
- try writer.writeByte(macho.BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM); // TODO Sometimes we might want to add flags.
- try writer.writeAll(entry.key);
- try writer.writeByte(0);
-
- try writer.writeByte(macho.BIND_OPCODE_DO_BIND);
- try writer.writeByte(macho.BIND_OPCODE_DONE);
- }
-}
src/link/MachO.zig
@@ -12,6 +12,7 @@ const aarch64 = @import("../codegen/aarch64.zig");
const math = std.math;
const mem = std.mem;
+const bind = @import("MachO/bind.zig");
const trace = @import("../tracy.zig").trace;
const build_options = @import("build_options");
const Module = @import("../Module.zig");
@@ -26,7 +27,6 @@ const Trie = @import("MachO/Trie.zig");
const CodeSignature = @import("MachO/CodeSignature.zig");
usingnamespace @import("MachO/commands.zig");
-usingnamespace @import("MachO/imports.zig");
pub const base_tag: File.Tag = File.Tag.macho;
@@ -108,9 +108,9 @@ locals: std.ArrayListUnmanaged(macho.nlist_64) = .{},
/// Table of all global symbols
globals: std.ArrayListUnmanaged(macho.nlist_64) = .{},
/// Table of all extern nonlazy symbols, indexed by name.
-nonlazy_imports: std.StringArrayHashMapUnmanaged(ExternSymbol) = .{},
+nonlazy_imports: std.StringArrayHashMapUnmanaged(Import) = .{},
/// Table of all extern lazy symbols, indexed by name.
-lazy_imports: std.StringArrayHashMapUnmanaged(ExternSymbol) = .{},
+lazy_imports: std.StringArrayHashMapUnmanaged(Import) = .{},
locals_free_list: std.ArrayListUnmanaged(u32) = .{},
globals_free_list: std.ArrayListUnmanaged(u32) = .{},
@@ -169,6 +169,17 @@ pie_fixups: std.ArrayListUnmanaged(PieFixup) = .{},
/// rather than sitting in the global scope.
stub_fixups: std.ArrayListUnmanaged(StubFixup) = .{},
+pub const Import = struct {
+ /// MachO symbol table entry.
+ symbol: macho.nlist_64,
+
+ /// Id of the dynamic library where the specified entries can be found.
+ dylib_ordinal: i64,
+
+ /// Index of this import within the import list.
+ index: u32,
+};
+
pub const PieFixup = struct {
/// Target address we wanted to address in absolute terms.
address: u64,
@@ -1285,9 +1296,6 @@ pub fn updateDecl(self: *MachO, module: *Module, decl: *Module.Decl) !void {
try self.writeStubInStubHelper(fixup.symbol);
try self.writeLazySymbolPointer(fixup.symbol);
- const extern_sym = &self.lazy_imports.items()[fixup.symbol].value;
- extern_sym.segment = self.data_segment_cmd_index.?;
- extern_sym.offset = fixup.symbol * @sizeOf(u64);
self.rebase_info_dirty = true;
self.lazy_binding_info_dirty = true;
}
@@ -2065,7 +2073,7 @@ pub fn populateMissingMetadata(self: *MachO) !void {
const name = try self.base.allocator.dupe(u8, "dyld_stub_binder");
const offset = try self.makeString("dyld_stub_binder");
try self.nonlazy_imports.putNoClobber(self.base.allocator, name, .{
- .inner = .{
+ .symbol = .{
.n_strx = offset,
.n_type = std.macho.N_UNDF | std.macho.N_EXT,
.n_sect = 0,
@@ -2073,8 +2081,7 @@ pub fn populateMissingMetadata(self: *MachO) !void {
.n_value = 0,
},
.dylib_ordinal = 1, // TODO this is currently hardcoded.
- .segment = self.data_const_segment_cmd_index.?,
- .offset = index * @sizeOf(u64),
+ .index = index,
});
self.binding_info_dirty = true;
}
@@ -2238,7 +2245,7 @@ pub fn addExternSymbol(self: *MachO, name: []const u8) !u32 {
const sym_name = try self.base.allocator.dupe(u8, name);
const dylib_ordinal = 1; // TODO this is now hardcoded, since we only support libSystem.
try self.lazy_imports.putNoClobber(self.base.allocator, sym_name, .{
- .inner = .{
+ .symbol = .{
.n_strx = offset,
.n_type = macho.N_UNDF | macho.N_EXT,
.n_sect = 0,
@@ -2246,6 +2253,7 @@ pub fn addExternSymbol(self: *MachO, name: []const u8) !u32 {
.n_value = 0,
},
.dylib_ordinal = dylib_ordinal,
+ .index = index,
});
log.debug("adding new extern symbol '{s}' with dylib ordinal '{}'", .{ name, dylib_ordinal });
return index;
@@ -2767,10 +2775,10 @@ fn writeAllGlobalAndUndefSymbols(self: *MachO) !void {
defer undefs.deinit();
try undefs.ensureCapacity(nundefs);
for (self.lazy_imports.items()) |entry| {
- undefs.appendAssumeCapacity(entry.value.inner);
+ undefs.appendAssumeCapacity(entry.value.symbol);
}
for (self.nonlazy_imports.items()) |entry| {
- undefs.appendAssumeCapacity(entry.value.inner);
+ undefs.appendAssumeCapacity(entry.value.symbol);
}
const locals_off = symtab.symoff;
@@ -2832,20 +2840,20 @@ fn writeIndirectSymbolTable(self: *MachO) !void {
var writer = stream.writer();
stubs.reserved1 = 0;
- for (self.lazy_imports.items()) |_, i| {
+ for (lazy) |_, i| {
const symtab_idx = @intCast(u32, dysymtab.iundefsym + i);
try writer.writeIntLittle(u32, symtab_idx);
}
const base_id = @intCast(u32, lazy.len);
got.reserved1 = base_id;
- for (self.nonlazy_imports.items()) |_, i| {
+ for (nonlazy) |_, i| {
const symtab_idx = @intCast(u32, dysymtab.iundefsym + i + base_id);
try writer.writeIntLittle(u32, symtab_idx);
}
la_symbol_ptr.reserved1 = got.reserved1 + @intCast(u32, nonlazy.len);
- for (self.lazy_imports.items()) |_, i| {
+ for (lazy) |_, i| {
const symtab_idx = @intCast(u32, dysymtab.iundefsym + i);
try writer.writeIntLittle(u32, symtab_idx);
}
@@ -2962,14 +2970,33 @@ fn writeRebaseInfoTable(self: *MachO) !void {
const tracy = trace(@src());
defer tracy.end();
- const size = try rebaseInfoSize(self.lazy_imports.items());
+ var pointers = std.ArrayList(bind.Pointer).init(self.base.allocator);
+ defer pointers.deinit();
+
+ if (self.la_symbol_ptr_section_index) |idx| {
+ try pointers.ensureCapacity(pointers.items.len + self.lazy_imports.items().len);
+ const seg = self.load_commands.items[self.data_segment_cmd_index.?].Segment;
+ const sect = seg.sections.items[idx];
+ const base_offset = sect.addr - seg.inner.vmaddr;
+ const segment_id = @intCast(u16, self.data_segment_cmd_index.?);
+
+ for (self.lazy_imports.items()) |entry| {
+ pointers.appendAssumeCapacity(.{
+ .offset = base_offset + entry.value.index * @sizeOf(u64),
+ .segment_id = segment_id,
+ });
+ }
+ }
+
+ std.sort.sort(bind.Pointer, pointers.items, {}, bind.pointerCmp);
+
+ const size = try bind.rebaseInfoSize(pointers.items);
var buffer = try self.base.allocator.alloc(u8, @intCast(usize, size));
defer self.base.allocator.free(buffer);
var stream = std.io.fixedBufferStream(buffer);
- try writeRebaseInfo(self.lazy_imports.items(), stream.writer());
+ try bind.writeRebaseInfo(pointers.items, stream.writer());
- const linkedit_segment = &self.load_commands.items[self.linkedit_segment_cmd_index.?].Segment;
const dyld_info = &self.load_commands.items[self.dyld_info_cmd_index.?].DyldInfoOnly;
const allocated_size = self.allocatedSizeLinkedit(dyld_info.rebase_off);
const needed_size = mem.alignForwardGeneric(u64, buffer.len, @alignOf(u64));
@@ -2994,14 +3021,33 @@ fn writeBindingInfoTable(self: *MachO) !void {
const tracy = trace(@src());
defer tracy.end();
- const size = try bindInfoSize(self.nonlazy_imports.items());
+ var pointers = std.ArrayList(bind.Pointer).init(self.base.allocator);
+ defer pointers.deinit();
+
+ if (self.data_got_section_index) |idx| {
+ try pointers.ensureCapacity(pointers.items.len + self.nonlazy_imports.items().len);
+ const seg = self.load_commands.items[self.data_const_segment_cmd_index.?].Segment;
+ const sect = seg.sections.items[idx];
+ const base_offset = sect.addr - seg.inner.vmaddr;
+ const segment_id = @intCast(u16, self.data_const_segment_cmd_index.?);
+
+ for (self.nonlazy_imports.items()) |entry| {
+ pointers.appendAssumeCapacity(.{
+ .offset = base_offset + entry.value.index * @sizeOf(u64),
+ .segment_id = segment_id,
+ .dylib_ordinal = entry.value.dylib_ordinal,
+ .name = entry.key,
+ });
+ }
+ }
+
+ const size = try bind.bindInfoSize(pointers.items);
var buffer = try self.base.allocator.alloc(u8, @intCast(usize, size));
defer self.base.allocator.free(buffer);
var stream = std.io.fixedBufferStream(buffer);
- try writeBindInfo(self.nonlazy_imports.items(), stream.writer());
+ try bind.writeBindInfo(pointers.items, stream.writer());
- const linkedit_segment = self.load_commands.items[self.linkedit_segment_cmd_index.?].Segment;
const dyld_info = &self.load_commands.items[self.dyld_info_cmd_index.?].DyldInfoOnly;
const allocated_size = self.allocatedSizeLinkedit(dyld_info.bind_off);
const needed_size = mem.alignForwardGeneric(u64, buffer.len, @alignOf(u64));
@@ -3023,14 +3069,36 @@ fn writeBindingInfoTable(self: *MachO) !void {
fn writeLazyBindingInfoTable(self: *MachO) !void {
if (!self.lazy_binding_info_dirty) return;
- const size = try lazyBindInfoSize(self.lazy_imports.items());
+ const tracy = trace(@src());
+ defer tracy.end();
+
+ var pointers = std.ArrayList(bind.Pointer).init(self.base.allocator);
+ defer pointers.deinit();
+
+ if (self.la_symbol_ptr_section_index) |idx| {
+ try pointers.ensureCapacity(self.lazy_imports.items().len);
+ const seg = self.load_commands.items[self.data_segment_cmd_index.?].Segment;
+ const sect = seg.sections.items[idx];
+ const base_offset = sect.addr - seg.inner.vmaddr;
+ const segment_id = @intCast(u16, self.data_segment_cmd_index.?);
+
+ for (self.lazy_imports.items()) |entry| {
+ pointers.appendAssumeCapacity(.{
+ .offset = base_offset + entry.value.index * @sizeOf(u64),
+ .segment_id = segment_id,
+ .dylib_ordinal = entry.value.dylib_ordinal,
+ .name = entry.key,
+ });
+ }
+ }
+
+ const size = try bind.lazyBindInfoSize(pointers.items);
var buffer = try self.base.allocator.alloc(u8, @intCast(usize, size));
defer self.base.allocator.free(buffer);
var stream = std.io.fixedBufferStream(buffer);
- try writeLazyBindInfo(self.lazy_imports.items(), stream.writer());
+ try bind.writeLazyBindInfo(pointers.items, stream.writer());
- const linkedit_segment = self.load_commands.items[self.linkedit_segment_cmd_index.?].Segment;
const dyld_info = &self.load_commands.items[self.dyld_info_cmd_index.?].DyldInfoOnly;
const allocated_size = self.allocatedSizeLinkedit(dyld_info.lazy_bind_off);
const needed_size = mem.alignForwardGeneric(u64, buffer.len, @alignOf(u64));