diff options
| -rw-r--r-- | src/link/MachO.zig | 37 | ||||
| -rw-r--r-- | src/link/MachO/commands.zig | 6 |
2 files changed, 21 insertions, 22 deletions
diff --git a/src/link/MachO.zig b/src/link/MachO.zig index e7ca3f9d6a..0892053a4f 100644 --- a/src/link/MachO.zig +++ b/src/link/MachO.zig @@ -281,6 +281,10 @@ const DEFAULT_DYLD_PATH: [*:0]const u8 = "/usr/lib/dyld"; const minimum_text_block_size = 64; pub const min_text_capacity = padToIdeal(minimum_text_block_size); +/// Virtual memory offset corresponds to the size of __PAGEZERO segment and start of +/// __TEXT segment. +const pagezero_vmsize: u64 = 0x100000000; + pub const Export = struct { sym_index: ?u32 = null, }; @@ -1903,13 +1907,19 @@ pub fn allocateAtom(self: *MachO, atom: *TextBlock, match: MatchingSection) !u64 const vaddr = outer: { if (!use_stage1) { const sym = &self.locals.items[atom.local_sym_index]; + const needs_padding = blk: { + // TODO is __text the only section that benefits from padding? + if (match.seg == self.text_segment_cmd_index.? and + match.sect == self.text_section_index.?) break :blk true; + break :blk false; + }; var atom_placement: ?*TextBlock = null; // TODO converge with `allocateTextBlock` and handle free list const vaddr = if (self.blocks.get(match)) |last| blk: { const last_atom_sym = self.locals.items[last.local_sym_index]; - const ideal_capacity = padToIdeal(last.size); + const ideal_capacity = if (needs_padding) padToIdeal(last.size) else last.size; const ideal_capacity_end_vaddr = last_atom_sym.n_value + ideal_capacity; const last_atom_alignment = try math.powi(u32, 2, atom.alignment); const new_start_vaddr = mem.alignForwardGeneric(u64, ideal_capacity_end_vaddr, last_atom_alignment); @@ -1921,18 +1931,9 @@ pub fn allocateAtom(self: *MachO, atom: *TextBlock, match: MatchingSection) !u64 const expand_section = atom_placement == null or atom_placement.?.next == null; if (expand_section) { - const needed_size = (vaddr + atom.size) - sect.addr; - const end_addr = blk: { - const next_ordinal = self.section_ordinals.getIndex(match).?; // Ordinals are +1 to begin with. - const end_addr = if (self.section_ordinals.keys().len > next_ordinal) inner: { - const next_match = self.section_ordinals.keys()[next_ordinal]; - const next_seg = self.load_commands.items[next_match.seg].Segment; - const next_sect = next_seg.sections.items[next_match.sect]; - break :inner next_sect.addr; - } else seg.inner.filesize; - break :blk end_addr; - }; - assert(needed_size <= end_addr); // TODO must expand the section + const max_size = seg.allocatedSize(vaddr - pagezero_vmsize); + log.debug(" (atom size 0x{x}, max available size 0x{x})", .{ atom.size, max_size }); + assert(atom.size <= max_size); // TODO must expand the section } const n_sect = @intCast(u8, self.section_ordinals.getIndex(match).? + 1); sym.n_value = vaddr; @@ -3912,7 +3913,7 @@ pub fn populateMissingMetadata(self: *MachO) !void { .Segment = .{ .inner = .{ .segname = makeStaticString("__PAGEZERO"), - .vmsize = 0x100000000, // size always set to 4GB + .vmsize = pagezero_vmsize, }, }, }); @@ -3932,7 +3933,7 @@ pub fn populateMissingMetadata(self: *MachO) !void { .Segment = .{ .inner = .{ .segname = makeStaticString("__TEXT"), - .vmaddr = 0x100000000, // always starts at 4GB + .vmaddr = pagezero_vmsize, .vmsize = needed_size, .filesize = needed_size, .maxprot = macho.VM_PROT_READ | macho.VM_PROT_EXECUTE, @@ -4452,8 +4453,6 @@ fn allocateSection( const padding: ?u64 = if (segment_id == self.text_segment_cmd_index.?) self.header_pad else null; const off = seg.findFreeSpace(size, alignment_pow_2, padding); - assert(off + size <= seg.inner.fileoff + seg.inner.filesize); // TODO expand - log.debug("found {s},{s} section free space 0x{x} to 0x{x}", .{ commands.segmentName(sect), commands.sectionName(sect), @@ -4556,7 +4555,9 @@ fn allocateTextBlock(self: *MachO, text_block: *TextBlock, new_block_size: u64, const expand_text_section = block_placement == null or block_placement.?.next == null; if (expand_text_section) { const needed_size = (vaddr + new_block_size) - text_section.addr; - assert(needed_size <= text_segment.inner.filesize); // TODO must move the entire text section. + const max_size = text_segment.allocatedSize(vaddr - pagezero_vmsize); + log.debug(" (atom needed size 0x{x}, max available size 0x{x})", .{ needed_size, max_size }); + assert(needed_size <= max_size); // TODO must expand the section _ = try self.blocks.put(self.base.allocator, match, text_block); } text_block.size = new_block_size; diff --git a/src/link/MachO/commands.zig b/src/link/MachO/commands.zig index ff7c5e841b..7bb1b12c32 100644 --- a/src/link/MachO/commands.zig +++ b/src/link/MachO/commands.zig @@ -246,10 +246,8 @@ pub const SegmentCommand = struct { } pub fn allocatedSize(self: SegmentCommand, start: u64) u64 { - assert(start > 0); - if (start == self.inner.fileoff) - return 0; - var min_pos: u64 = std.math.maxInt(u64); + assert(start >= self.inner.fileoff); + var min_pos: u64 = self.inner.fileoff + self.inner.filesize; for (self.sections.items) |section| { if (section.offset <= start) continue; if (section.offset < min_pos) min_pos = section.offset; |