mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2026-02-14 05:20:34 +00:00
Code Issues Packages Projects Releases Wiki Activity

elf: write .got in bulk after scanning objects

Browse Source
This commit is contained in:
Jakub Konka 2023-10-02 17:16:27 +02:00
parent d565f8bef2
commit 87602092fa
1 changed files with 34 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
src/link/Elf.zig
View File

@ -111,7 +111,7 @@ symbols_free_list: std.ArrayListUnmanaged(Symbol.Index) = .{},
phdr_table_dirty: bool = false,
shdr_table_dirty: bool = false,
got_dirty: bool = false,
got_addresses_dirty: bool = false,
debug_strtab_dirty: bool = false,
debug_abbrev_section_dirty: bool = false,
@ -942,7 +942,7 @@ pub fn growAllocSection(self: *Elf, shdr_index: u16, needed_size: u64) !void {
// and grow.
{
const dirty_addr = phdr.p_vaddr + phdr.p_memsz;
self.got_dirty = for (self.got.entries.items) |entry| {
self.got_addresses_dirty = for (self.got.entries.items) |entry| {
if (self.symbol(entry.symbol_index).value >= dirty_addr) break true;
} else false;
@ -1333,15 +1333,6 @@ pub fn flushModule(self: *Elf, comp: *Compilation, prog_node: *std.Progress.Node
}
try self.writeObjects();
if (self.got_dirty) {
const shdr = &self.shdrs.items[self.got_section_index.?];
var buffer = try std.ArrayList(u8).initCapacity(gpa, self.got.size(self));
defer buffer.deinit();
try self.got.writeAllEntries(self, buffer.writer());
try self.base.file.?.pwriteAll(buffer.items, shdr.sh_offset);
self.got_dirty = false;
}
// Look for entry address in objects if not set by the incremental compiler.
if (self.entry_addr == null) {
const entry: ?[]const u8 = entry: {
@ -1541,6 +1532,7 @@ pub fn flushModule(self: *Elf, comp: *Compilation, prog_node: *std.Progress.Node
assert(!self.shdr_table_dirty);
assert(!self.debug_strtab_dirty);
assert(!self.got.dirty);
assert(!self.got_addresses_dirty);
}
const ParseError = error{
@ -1789,8 +1781,7 @@ fn scanRelocs(self: *Elf) !void {
if (sym.flags.needs_got) {
log.debug("'{s}' needs GOT", .{sym.name(self)});
// TODO how can we tell we need to write it again, aka the entry is dirty?
const gop = try sym.getOrCreateGotEntry(@intCast(sym_index), self);
try self.got.writeEntry(self, gop.index);
_ = try sym.getOrCreateGotEntry(@intCast(sym_index), self);
}
}
}
@ -3472,6 +3463,15 @@ fn initSyntheticSections(self: *Elf) !void {
.p64 => false,
};
if (self.got.entries.items.len > 0 and self.got_section_index == null) {
self.got_section_index = try self.addSection(.{
.name = ".got",
.type = elf.SHT_PROGBITS,
.flags = elf.SHF_ALLOC | elf.SHF_WRITE,
.addralign = self.ptrWidthBytes(),
});
}
if (self.symtab_section_index == null) {
self.symtab_section_index = try self.addSection(.{
.name = ".symtab",
@ -3499,9 +3499,18 @@ fn initSyntheticSections(self: *Elf) !void {
}
fn updateSyntheticSectionSizes(self: *Elf) !void {
if (self.got_section_index) |index| {
if (self.got.dirty) {
try self.growAllocSection(index, self.got.size(self));
self.got.dirty = false;
self.got_addresses_dirty = true;
}
}
if (self.symtab_section_index != null) {
try self.updateSymtabSize();
}
if (self.strtab_section_index) |index| {
// TODO I don't really this here but we need it to add symbol names from GOT and other synthetic
// sections into .strtab for easier debugging.
@ -3510,6 +3519,7 @@ fn updateSyntheticSectionSizes(self: *Elf) !void {
}
try self.growNonAllocSection(index, self.strtab.buffer.items.len, 1, false);
}
if (self.shstrtab_section_index) |index| {
try self.growNonAllocSection(index, self.shstrtab.buffer.items.len, 1, false);
}
@ -3560,14 +3570,25 @@ fn updateSymtabSize(self: *Elf) !void {
}
fn writeSyntheticSections(self: *Elf) !void {
if (self.got_addresses_dirty) {
const shdr = &self.shdrs.items[self.got_section_index.?];
var buffer = try std.ArrayList(u8).initCapacity(self.base.allocator, self.got.size(self));
defer buffer.deinit();
try self.got.writeAllEntries(self, buffer.writer());
try self.base.file.?.pwriteAll(buffer.items, shdr.sh_offset);
self.got_addresses_dirty = false;
}
if (self.shstrtab_section_index) |index| {
const shdr = self.shdrs.items[index];
try self.base.file.?.pwriteAll(self.shstrtab.buffer.items, shdr.sh_offset);
}
if (self.strtab_section_index) |index| {
const shdr = self.shdrs.items[index];
try self.base.file.?.pwriteAll(self.strtab.buffer.items, shdr.sh_offset);
}
if (self.symtab_section_index) |_| {
try self.writeSymtab();
}