Commit ce8886d57d1593a7eb4909e518fc49e1c95360dd | zig

src/link/Elf/Atom.zig+12-23

...	...	@@ -750,8 +750,6 @@ pub fn resolveRelocsAlloc(self: Atom, elf_file: *Elf, code: []u8) RelocError!voi
750	750	const S = target.address(.{}, elf_file);
751	751	// Address of the global offset table.
752	752	const GOT = elf_file.gotAddress();
753		// Address of the zig jump table entry if any.
754		const ZJT = target.zigJumpTableAddress(elf_file);
755	753	// Relative offset to the start of the global offset table.
756	754	const G = target.gotAddress(elf_file) - GOT;
757	755	// // Address of the thread pointer.
...	...	@@ -759,19 +757,18 @@ pub fn resolveRelocsAlloc(self: Atom, elf_file: *Elf, code: []u8) RelocError!voi
759	757	// Address of the dynamic thread pointer.
760	758	const DTP = elf_file.dtpAddress();
761	759
762		relocs_log.debug(" {s}: {x}: [{x} => {x}] GOT({x}) ZJT({x}) ({s})", .{
	760	relocs_log.debug(" {s}: {x}: [{x} => {x}] GOT({x}) ({s})", .{
763	761	relocation.fmtRelocType(rel.r_type(), cpu_arch),
764	762	r_offset,
765	763	P,
766	764	S + A,
767	765	G + GOT + A,
768		ZJT + A,
769	766	target.name(elf_file),
770	767	});
771	768
772	769	try stream.seekTo(r_offset);
773	770
774		const args = ResolveArgs{ P, A, S, GOT, G, TP, DTP, ZJT };
	771	const args = ResolveArgs{ P, A, S, GOT, G, TP, DTP };
775	772
776	773	switch (cpu_arch) {
777	774	.x86_64 => x86_64.resolveRelocAlloc(self, elf_file, rel, target, args, &it, code, &stream) catch \|err\| switch (err) {
...	...	@@ -956,7 +953,7 @@ pub fn resolveRelocsNonAlloc(self: Atom, elf_file: *Elf, code: []u8, undefs: any
956	953	// Address of the dynamic thread pointer.
957	954	const DTP = elf_file.dtpAddress();
958	955
959		const args = ResolveArgs{ P, A, S, GOT, 0, 0, DTP, 0 };
	956	const args = ResolveArgs{ P, A, S, GOT, 0, 0, DTP };
960	957
961	958	relocs_log.debug(" {}: {x}: [{x} => {x}] ({s})", .{
962	959	relocation.fmtRelocType(rel.r_type(), cpu_arch),
...	...	@@ -1200,7 +1197,7 @@ const x86_64 = struct {
1200	1197
1201	1198	const cwriter = stream.writer();
1202	1199
1203		const P, const A, const S, const GOT, const G, const TP, const DTP, const ZJT = args;
	1200	const P, const A, const S, const GOT, const G, const TP, const DTP = args;
1204	1201
1205	1202	switch (r_type) {
1206	1203	.NONE => unreachable,
...	...	@@ -1215,10 +1212,7 @@ const x86_64 = struct {
1215	1212	);
1216	1213	},
1217	1214
1218		.PLT32 => {
1219		const S_ = if (target.flags.zig_jump_table) ZJT else S;
1220		try cwriter.writeInt(i32, @as(i32, @intCast(S_ + A - P)), .little);
1221		},
	1215	.PLT32 => try cwriter.writeInt(i32, @as(i32, @intCast(S + A - P)), .little),
1222	1216	.PC32 => try cwriter.writeInt(i32, @as(i32, @intCast(S + A - P)), .little),
1223	1217
1224	1218	.GOTPCREL => try cwriter.writeInt(i32, @as(i32, @intCast(G + GOT + A - P)), .little),
...	...	@@ -1243,10 +1237,7 @@ const x86_64 = struct {
1243	1237	try cwriter.writeInt(i32, @as(i32, @intCast(G + GOT + A - P)), .little);
1244	1238	},
1245	1239
1246		.@"32" => {
1247		const S_ = if (target.flags.zig_jump_table) ZJT else S;
1248		try cwriter.writeInt(u32, @as(u32, @truncate(@as(u64, @intCast(S_ + A)))), .little);
1249		},
	1240	.@"32" => try cwriter.writeInt(u32, @as(u32, @truncate(@as(u64, @intCast(S + A)))), .little),
1250	1241	.@"32S" => try cwriter.writeInt(i32, @as(i32, @truncate(S + A)), .little),
1251	1242
1252	1243	.TPOFF32 => try cwriter.writeInt(i32, @as(i32, @truncate(S + A - TP)), .little),
...	...	@@ -1345,7 +1336,7 @@ const x86_64 = struct {
1345	1336	const r_type: elf.R_X86_64 = @enumFromInt(rel.r_type());
1346	1337	const cwriter = stream.writer();
1347	1338
1348		_, const A, const S, const GOT, _, _, const DTP, _ = args;
	1339	_, const A, const S, const GOT, _, _, const DTP = args;
1349	1340
1350	1341	switch (r_type) {
1351	1342	.NONE => unreachable,
...	...	@@ -1728,9 +1719,8 @@ const aarch64 = struct {
1728	1719	const code = code_buffer[r_offset..][0..4];
1729	1720	const file_ptr = atom.file(elf_file).?;
1730	1721
1731		const P, const A, const S, const GOT, const G, const TP, const DTP, const ZJT = args;
	1722	const P, const A, const S, const GOT, const G, const TP, const DTP = args;
1732	1723	_ = DTP;
1733		_ = ZJT;
1734	1724
1735	1725	switch (r_type) {
1736	1726	.NONE => unreachable,
...	...	@@ -1932,7 +1922,7 @@ const aarch64 = struct {
1932	1922	const r_type: elf.R_AARCH64 = @enumFromInt(rel.r_type());
1933	1923	const cwriter = stream.writer();
1934	1924
1935		_, const A, const S, _, _, _, _, _ = args;
	1925	_, const A, const S, _, _, _, _ = args;
1936	1926
1937	1927	switch (r_type) {
1938	1928	.NONE => unreachable,
...	...	@@ -2012,10 +2002,9 @@ const riscv = struct {
2012	2002	const r_offset = std.math.cast(usize, rel.r_offset) orelse return error.Overflow;
2013	2003	const cwriter = stream.writer();
2014	2004
2015		const P, const A, const S, const GOT, const G, const TP, const DTP, const ZJT = args;
	2005	const P, const A, const S, const GOT, const G, const TP, const DTP = args;
2016	2006	_ = TP;
2017	2007	_ = DTP;
2018		_ = ZJT;
2019	2008
2020	2009	switch (r_type) {
2021	2010	.NONE => unreachable,
...	...	@@ -2167,7 +2156,7 @@ const riscv = struct {
2167	2156	const r_offset = std.math.cast(usize, rel.r_offset) orelse return error.Overflow;
2168	2157	const cwriter = stream.writer();
2169	2158
2170		_, const A, const S, const GOT, _, _, const DTP, _ = args;
	2159	_, const A, const S, const GOT, _, _, const DTP = args;
2171	2160	_ = GOT;
2172	2161	_ = DTP;
2173	2162
...	...	@@ -2203,7 +2192,7 @@ const riscv = struct {
2203	2192	const riscv_util = @import("../riscv.zig");
2204	2193	};
2205	2194
2206		const ResolveArgs = struct { i64, i64, i64, i64, i64, i64, i64, i64 };
	2195	const ResolveArgs = struct { i64, i64, i64, i64, i64, i64, i64 };
2207	2196
2208	2197	const RelocError = error{
2209	2198	Overflow,

src/link/Elf/Symbol.zig+12-9

...	...	@@ -101,7 +101,7 @@ pub fn symbolRank(symbol: Symbol, elf_file: *Elf) u32 {
101	101	return file_ptr.symbolRank(sym, in_archive);
102	102	}
103	103
104		pub fn address(symbol: Symbol, opts: struct { plt: bool = true }, elf_file: *Elf) i64 {
	104	pub fn address(symbol: Symbol, opts: struct { plt: bool = true, zjt: bool = true }, elf_file: *Elf) i64 {
105	105	if (symbol.mergeSubsection(elf_file)) \|msub\| {
106	106	if (!msub.alive) return 0;
107	107	return msub.address(elf_file) + symbol.value;
...	...	@@ -109,6 +109,9 @@ pub fn address(symbol: Symbol, opts: struct { plt: bool = true }, elf_file: *Elf
109	109	if (symbol.flags.has_copy_rel) {
110	110	return symbol.copyRelAddress(elf_file);
111	111	}
	112	if (symbol.flags.has_zjt and opts.zjt) {
	113	return symbol.zjtAddress(elf_file);
	114	}
112	115	if (symbol.flags.has_plt and opts.plt) {
113	116	if (!symbol.flags.is_canonical and symbol.flags.has_got) {
114	117	// We have a non-lazy bound function pointer, use that!
...	...	@@ -217,12 +220,12 @@ pub fn tlsDescAddress(symbol: Symbol, elf_file: *Elf) i64 {
217	220	return entry.address(elf_file);
218	221	}
219	222
220		pub fn zigJumpTableAddress(symbol: Symbol, elf_file: *Elf) i64 {
221		if (!symbol.flags.zig_jump_table) return 0;
	223	pub fn zjtAddress(symbol: Symbol, elf_file: *Elf) i64 {
	224	if (!symbol.flags.has_zjt) return 0;
222	225	const zo = elf_file.zigObjectPtr().?;
223	226	const jump_table = zo.jumpTablePtr().?;
224		const jt_index = symbol.extra(elf_file).zig_jump_table;
225		return jump_table.entryAddress(jt_index, zo, elf_file);
	227	const index = symbol.extra(elf_file).zjt;
	228	return jump_table.entryAddress(index, zo, elf_file);
226	229	}
227	230
228	231	pub fn dsoAlignment(symbol: Symbol, elf_file: *Elf) !u64 {
...	...	@@ -248,7 +251,7 @@ const AddExtraOpts = struct {
248	251	tlsgd: ?u32 = null,
249	252	gottp: ?u32 = null,
250	253	tlsdesc: ?u32 = null,
251		zig_jump_table: ?u32 = null,
	254	zjt: ?u32 = null,
252	255	};
253	256
254	257	pub fn addExtra(symbol: Symbol, opts: AddExtraOpts, elf_file: Elf) void {
...	...	@@ -377,7 +380,7 @@ fn format2(
377	380	try writer.print("%{d} : {s} : @{x}", .{
378	381	symbol.esym_index,
379	382	symbol.fmtName(elf_file),
380		symbol.address(.{}, elf_file),
	383	symbol.address(.{ .plt = false, .zjt = false }, elf_file),
381	384	});
382	385	if (symbol.file(elf_file)) \|file_ptr\| {
383	386	if (symbol.isAbs(elf_file)) {
...	...	@@ -454,7 +457,7 @@ pub const Flags = packed struct {
454	457	merge_subsection: bool = false,
455	458
456	459	/// Whether the symbol has __zig_jump_table indirection.
457		zig_jump_table: bool = false,
	460	has_zjt: bool = false,
458	461	};
459	462
460	463	pub const Extra = struct {
...	...	@@ -468,7 +471,7 @@ pub const Extra = struct {
468	471	gottp: u32 = 0,
469	472	tlsdesc: u32 = 0,
470	473	merge_section: u32 = 0,
471		zig_jump_table: u32 = 0,
	474	zjt: u32 = 0,
472	475	};
473	476
474	477	pub const Index = u32;

src/link/Elf/ZigObject.zig+11-6

...	...	@@ -918,7 +918,7 @@ fn updateNavCode(
918	918	if (stt_bits == elf.STT_FUNC) {
919	919	const extra = sym.extra(elf_file);
920	920	const jump_table = self.jumpTablePtr().?;
921		jump_table.entries.items(.dirty)[extra.zig_jump_table] = true;
	921	jump_table.entries.items(.dirty)[extra.zjt] = true;
922	922	}
923	923	}
924	924	} else if (code.len < old_size) {
...	...	@@ -1045,10 +1045,10 @@ pub fn updateFunc(
1045	1045
1046	1046	{
1047	1047	const sym = self.symbol(sym_index);
1048		if (!sym.flags.zig_jump_table) {
	1048	if (!sym.flags.has_zjt) {
1049	1049	const index = try jump_table.addSymbol(gpa, sym_index);
1050		sym.flags.zig_jump_table = true;
1051		sym.addExtra(.{ .zig_jump_table = index }, elf_file);
	1050	sym.flags.has_zjt = true;
	1051	sym.addExtra(.{ .zjt = index }, elf_file);
1052	1052	try jump_table.updateSize(self, elf_file);
1053	1053	const old_vaddr = jump_table.address(self, elf_file);
1054	1054	try self.symbol(jump_table.sym_index).atom(elf_file).?.allocate(elf_file);
...	...	@@ -1108,7 +1108,7 @@ pub fn updateFunc(
1108	1108	}
1109	1109	} else {
1110	1110	const sym = self.symbol(sym_index);
1111		const jt_index = sym.extra(elf_file).zig_jump_table;
	1111	const jt_index = sym.extra(elf_file).zjt;
1112	1112	var jt_entry = jump_table.entries.get(jt_index);
1113	1113	if (jt_entry.dirty) {
1114	1114	try jump_table.writeEntry(jt_index, self, elf_file);
...	...	@@ -1896,7 +1896,12 @@ pub const JumpTable = struct {
1896	1896	try writer.print(" @{x} : size({x})\n", .{ jt.address(zo, ef), jt.size(zo, ef) });
1897	1897	for (jt.entries.items(.sym_index), jt.entries.items(.dirty)) \|sym_index, dirty\| {
1898	1898	const sym = zo.symbol(sym_index);
1899		try writer.print(" %{d} : {s} : @{x}", .{ sym_index, sym.name(ef), sym.address(.{}, ef) });
	1899	try writer.print(" {x} => {x} : %{d} : {s}", .{
	1900	sym.address(.{}, ef),
	1901	sym.address(.{ .zjt = false }, ef),
	1902	sym_index,
	1903	sym.name(ef),
	1904	});
1900	1905	if (dirty) try writer.writeAll(" : [!]");
1901	1906	try writer.writeByte('\n');
1902	1907	}

author	Jakub Konka <kubkon@jakubkonka.com> 2024-08-13 10:28:01+02:00
committer	Jakub Konka <kubkon@jakubkonka.com> 2024-08-13 13:30:24+02:00
log	ce8886d57d1593a7eb4909e518fc49e1c95360dd
tree	f9000ced65ae45021af02da0474dac13a03e77c6
parent	d25c93a868585e4e2f5941fcff15fa49c90510e9

elf: make zig jump table indirection implicit via Symbol.address