mirror of
https://github.com/ziglang/zig.git
synced 2024-11-27 07:32:44 +00:00
macho: extract writing stub helper preamble into fn
This commit is contained in:
Jakub Konka
parent
3df2ae1f9d
commit
1181543dad
@ -2079,62 +2079,7 @@ pub fn populateMissingMetadata(self: *MachO) !void {
|
||||
self.binding_info_dirty = true;
|
||||
}
|
||||
if (self.stub_helper_stubs_start_off == null) {
|
||||
const text_segment = &self.load_commands.items[self.text_segment_cmd_index.?].Segment;
|
||||
const stub_helper = &text_segment.sections.items[self.stub_helper_section_index.?];
|
||||
const data_segment = &self.load_commands.items[self.data_segment_cmd_index.?].Segment;
|
||||
const data = &data_segment.sections.items[self.data_section_index.?];
|
||||
const data_const_segment = &self.load_commands.items[self.data_const_segment_cmd_index.?].Segment;
|
||||
const got = &data_const_segment.sections.items[self.data_got_section_index.?];
|
||||
switch (self.base.options.target.cpu.arch) {
|
||||
.x86_64 => {
|
||||
const code_size = 15;
|
||||
var code: [code_size]u8 = undefined;
|
||||
// lea %r11, [rip + disp]
|
||||
code[0] = 0x4c;
|
||||
code[1] = 0x8d;
|
||||
code[2] = 0x1d;
|
||||
{
|
||||
const displacement = try math.cast(u32, data.addr - stub_helper.addr - 7);
|
||||
mem.writeIntLittle(u32, code[3..7], displacement);
|
||||
}
|
||||
// push %r11
|
||||
code[7] = 0x41;
|
||||
code[8] = 0x53;
|
||||
// jmp [rip + disp]
|
||||
code[9] = 0xff;
|
||||
code[10] = 0x25;
|
||||
{
|
||||
const displacement = try math.cast(u32, got.addr - stub_helper.addr - code_size);
|
||||
mem.writeIntLittle(u32, code[11..], displacement);
|
||||
}
|
||||
self.stub_helper_stubs_start_off = stub_helper.offset + code_size;
|
||||
try self.base.file.?.pwriteAll(&code, stub_helper.offset);
|
||||
},
|
||||
.aarch64 => {
|
||||
var code: [4 * @sizeOf(u32)]u8 = undefined;
|
||||
{
|
||||
const displacement = try math.cast(i21, data.addr - stub_helper.addr);
|
||||
mem.writeIntLittle(u32, code[0..4], aarch64.Instruction.adr(.x17, displacement).toU32());
|
||||
}
|
||||
mem.writeIntLittle(u32, code[4..8], aarch64.Instruction.stp(
|
||||
.x16,
|
||||
.x17,
|
||||
aarch64.Register.sp,
|
||||
aarch64.Instruction.LoadStorePairOffset.pre_index(-16),
|
||||
).toU32());
|
||||
{
|
||||
const displacement = try math.divExact(u64, got.addr - stub_helper.addr - 2 * @sizeOf(u32), 4);
|
||||
const literal = try math.cast(u19, displacement);
|
||||
mem.writeIntLittle(u32, code[8..12], aarch64.Instruction.ldr(.x16, .{
|
||||
.literal = literal,
|
||||
}).toU32());
|
||||
}
|
||||
mem.writeIntLittle(u32, code[12..16], aarch64.Instruction.br(.x16).toU32());
|
||||
self.stub_helper_stubs_start_off = stub_helper.offset + 4 * @sizeOf(u32);
|
||||
try self.base.file.?.pwriteAll(&code, stub_helper.offset);
|
||||
},
|
||||
else => unreachable,
|
||||
}
|
||||
try self.writeStubHelperPreamble();
|
||||
}
|
||||
}
|
||||
|
||||
@ -2516,6 +2461,133 @@ fn writeLazySymbolPointer(self: *MachO, index: u32) !void {
|
||||
try self.base.file.?.pwriteAll(&buf, off);
|
||||
}
|
||||
|
||||
fn writeStubHelperPreamble(self: *MachO) !void {
|
||||
const text_segment = &self.load_commands.items[self.text_segment_cmd_index.?].Segment;
|
||||
const stub_helper = &text_segment.sections.items[self.stub_helper_section_index.?];
|
||||
const data_const_segment = &self.load_commands.items[self.data_const_segment_cmd_index.?].Segment;
|
||||
const got = &data_const_segment.sections.items[self.data_got_section_index.?];
|
||||
const data_segment = &self.load_commands.items[self.data_segment_cmd_index.?].Segment;
|
||||
const data = &data_segment.sections.items[self.data_section_index.?];
|
||||
|
||||
switch (self.base.options.target.cpu.arch) {
|
||||
.x86_64 => {
|
||||
const code_size = 15;
|
||||
var code: [code_size]u8 = undefined;
|
||||
// lea %r11, [rip + disp]
|
||||
code[0] = 0x4c;
|
||||
code[1] = 0x8d;
|
||||
code[2] = 0x1d;
|
||||
{
|
||||
const target_addr = data.addr;
|
||||
const displacement = try math.cast(u32, target_addr - stub_helper.addr - 7);
|
||||
mem.writeIntLittle(u32, code[3..7], displacement);
|
||||
}
|
||||
// push %r11
|
||||
code[7] = 0x41;
|
||||
code[8] = 0x53;
|
||||
// jmp [rip + disp]
|
||||
code[9] = 0xff;
|
||||
code[10] = 0x25;
|
||||
{
|
||||
const displacement = try math.cast(u32, got.addr - stub_helper.addr - code_size);
|
||||
mem.writeIntLittle(u32, code[11..], displacement);
|
||||
}
|
||||
try self.base.file.?.pwriteAll(&code, stub_helper.offset);
|
||||
self.stub_helper_stubs_start_off = stub_helper.offset + code_size;
|
||||
},
|
||||
.aarch64 => {
|
||||
var code: [6 * @sizeOf(u32)]u8 = undefined;
|
||||
|
||||
data_blk_outer: {
|
||||
const this_addr = stub_helper.addr;
|
||||
const target_addr = data.addr;
|
||||
data_blk: {
|
||||
const displacement = math.cast(i21, target_addr - this_addr) catch |_| break :data_blk;
|
||||
// adr x17, disp
|
||||
mem.writeIntLittle(u32, code[0..4], aarch64.Instruction.adr(.x17, displacement).toU32());
|
||||
// nop
|
||||
mem.writeIntLittle(u32, code[4..8], aarch64.Instruction.nop().toU32());
|
||||
break :data_blk_outer;
|
||||
}
|
||||
data_blk: {
|
||||
const new_this_addr = this_addr + @sizeOf(u32);
|
||||
const displacement = math.cast(i21, target_addr - new_this_addr) catch |_| break :data_blk;
|
||||
// nop
|
||||
mem.writeIntLittle(u32, code[0..4], aarch64.Instruction.nop().toU32());
|
||||
// adr x17, disp
|
||||
mem.writeIntLittle(u32, code[4..8], aarch64.Instruction.adr(.x17, displacement).toU32());
|
||||
break :data_blk_outer;
|
||||
}
|
||||
// Jump is too big, replace adr with adrp and add.
|
||||
const this_page = @intCast(i32, this_addr >> 12);
|
||||
const target_page = @intCast(i32, target_addr >> 12);
|
||||
const pages = @intCast(i21, target_page - this_page);
|
||||
// adrp x17, pages
|
||||
mem.writeIntLittle(u32, code[0..4], aarch64.Instruction.adrp(.x17, pages).toU32());
|
||||
const narrowed = @truncate(u12, target_addr);
|
||||
mem.writeIntLittle(u32, code[4..8], aarch64.Instruction.add(.x17, .x17, narrowed, false).toU32());
|
||||
}
|
||||
|
||||
// stp x16, x17, [sp, #-16]!
|
||||
mem.writeIntLittle(u32, code[8..12], aarch64.Instruction.stp(
|
||||
.x16,
|
||||
.x17,
|
||||
aarch64.Register.sp,
|
||||
aarch64.Instruction.LoadStorePairOffset.pre_index(-16),
|
||||
).toU32());
|
||||
|
||||
binder_blk_outer: {
|
||||
const this_addr = stub_helper.addr + 3 * @sizeOf(u32);
|
||||
const target_addr = got.addr;
|
||||
binder_blk: {
|
||||
const displacement = math.divExact(u64, target_addr - this_addr, 4) catch |_| break :binder_blk;
|
||||
const literal = math.cast(u18, displacement) catch |_| break :binder_blk;
|
||||
// ldr x16, label
|
||||
mem.writeIntLittle(u32, code[12..16], aarch64.Instruction.ldr(.x16, .{
|
||||
.literal = literal,
|
||||
}).toU32());
|
||||
// nop
|
||||
mem.writeIntLittle(u32, code[16..20], aarch64.Instruction.nop().toU32());
|
||||
break :binder_blk_outer;
|
||||
}
|
||||
binder_blk: {
|
||||
const new_this_addr = this_addr + @sizeOf(u32);
|
||||
const displacement = math.divExact(u64, target_addr - new_this_addr, 4) catch |_| break :binder_blk;
|
||||
const literal = math.cast(u18, displacement) catch |_| break :binder_blk;
|
||||
// nop
|
||||
mem.writeIntLittle(u32, code[12..16], aarch64.Instruction.nop().toU32());
|
||||
// ldr x16, label
|
||||
mem.writeIntLittle(u32, code[16..20], aarch64.Instruction.ldr(.x16, .{
|
||||
.literal = literal,
|
||||
}).toU32());
|
||||
break :binder_blk_outer;
|
||||
}
|
||||
// Jump is too big, replace ldr with adrp and ldr(register).
|
||||
const this_page = @intCast(i32, this_addr >> 12);
|
||||
const target_page = @intCast(i32, target_addr >> 12);
|
||||
const pages = @intCast(i21, target_page - this_page);
|
||||
// adrp x16, pages
|
||||
mem.writeIntLittle(u32, code[12..16], aarch64.Instruction.adrp(.x16, pages).toU32());
|
||||
const narrowed = @truncate(u12, target_addr);
|
||||
const offset = try math.divExact(u12, narrowed, 8);
|
||||
// ldr x16, x16, offset
|
||||
mem.writeIntLittle(u32, code[16..20], aarch64.Instruction.ldr(.x16, .{
|
||||
.register = .{
|
||||
.rn = .x16,
|
||||
.offset = aarch64.Instruction.LoadStoreOffset.imm(offset),
|
||||
},
|
||||
}).toU32());
|
||||
}
|
||||
|
||||
// br x16
|
||||
mem.writeIntLittle(u32, code[20..24], aarch64.Instruction.br(.x16).toU32());
|
||||
try self.base.file.?.pwriteAll(&code, stub_helper.offset);
|
||||
self.stub_helper_stubs_start_off = stub_helper.offset + code.len;
|
||||
},
|
||||
else => unreachable,
|
||||
}
|
||||
}
|
||||
|
||||
fn writeStub(self: *MachO, index: u32) !void {
|
||||
const text_segment = self.load_commands.items[self.text_segment_cmd_index.?].Segment;
|
||||
const stubs = text_segment.sections.items[self.stubs_section_index.?];
|
||||
|
||||
Loading…
Reference in New Issue
Block a user