macho: init all sections and mark atoms dead after

kubkon · Dec 16, 2023 · ef57b0e · ef57b0e
1 parent 228be14
commit ef57b0e
Showing 1 changed file with 18 additions and 12 deletions.
diff --git a/src/MachO/Object.zig b/src/MachO/Object.zig
@@ -130,6 +130,18 @@ pub fn parse(self: *Object, macho_file: *MachO) !void {
 
     self.initPlatform();
     try self.initDwarfInfo(gpa);
+
+    for (self.sections.items(.header), self.sections.items(.subsections)) |sect, subs| {
+        if (sect.attrs() & macho.S_ATTR_DEBUG == 0) continue;
+        if (!mem.eql(u8, sect.sectName(), "__eh_frame")) continue;
+        if (!mem.eql(u8, sect.sectName(), "__compact_unwind")) continue;
+        for (subs.items) |sub| {
+            macho_file.getAtom(sub.atom).?.flags = .{
+                .alive = false,
+                .visited = true,
+            };
+        }
+    }
 }
 
 inline fn isLiteral(sect: macho.section_64) bool {
@@ -148,9 +160,6 @@ fn initSubsections(self: *Object, nlists: anytype, macho_file: *MachO) !void {
     const gpa = macho_file.base.allocator;
     const slice = self.sections.slice();
     for (slice.items(.header), slice.items(.subsections), 0..) |sect, *subsections, n_sect| {
-        if (sect.attrs() & macho.S_ATTR_DEBUG != 0) continue;
-        if (self.eh_frame_sect_index) |index| if (index == n_sect) continue;
-        if (self.compact_unwind_sect_index) |index| if (index == n_sect) continue;
         if (isLiteral(sect)) continue;
 
         const nlist_start = for (nlists, 0..) |nlist, i| {
@@ -220,9 +229,6 @@ fn initSections(self: *Object, nlists: anytype, macho_file: *MachO) !void {
     try self.atoms.ensureUnusedCapacity(gpa, self.sections.items(.header).len);
 
     for (slice.items(.header), 0..) |sect, n_sect| {
-        if (sect.attrs() & macho.S_ATTR_DEBUG != 0) continue;
-        if (self.eh_frame_sect_index) |index| if (index == n_sect) continue;
-        if (self.compact_unwind_sect_index) |index| if (index == n_sect) continue;
         if (isLiteral(sect)) continue;
 
         const name = try std.fmt.allocPrintZ(gpa, "{s}${s}", .{ sect.segName(), sect.sectName() });
@@ -297,9 +303,6 @@ fn initLiteralSections(self: *Object, macho_file: *MachO) !void {
     try self.atoms.ensureUnusedCapacity(gpa, self.sections.items(.header).len);
 
     for (slice.items(.header), 0..) |sect, n_sect| {
-        if (sect.attrs() & macho.S_ATTR_DEBUG != 0) continue;
-        if (self.eh_frame_sect_index) |index| if (index == n_sect) continue;
-        if (self.compact_unwind_sect_index) |index| if (index == n_sect) continue;
         if (!isLiteral(sect)) continue;
 
         const name = try std.fmt.allocPrintZ(gpa, "{s}${s}", .{ sect.segName(), sect.sectName() });
@@ -318,7 +321,9 @@ fn initLiteralSections(self: *Object, macho_file: *MachO) !void {
 
 pub fn findAtom(self: Object, addr: u64) ?Atom.Index {
     for (self.sections.items(.header), 0..) |sect, n_sect| {
-        if (sect.addr <= addr and addr < sect.addr + sect.size) {
+        if ((sect.addr <= addr and addr < sect.addr + sect.size) or
+            (sect.addr == addr and sect.size == 0))
+        {
             return self.findAtomInSection(addr, @intCast(n_sect));
         }
     }
@@ -337,15 +342,16 @@ fn findAtomInSection(self: Object, addr: u64, n_sect: u8) ?Atom.Index {
             subsections.items[idx + 1].off - sub.off
         else
             sect.size - sub.off;
-        if (sub_addr <= addr and addr < sub_addr + sub_size) return sub.atom;
+        if ((sub_addr <= addr and addr < sub_addr + sub_size) or
+            (sub_addr == addr and sub_size == 0))
+            return sub.atom;
     }
     return null;
 }
 
 fn linkNlistToAtom(self: *Object, macho_file: *MachO) !void {
     for (self.symtab.items(.nlist), self.symtab.items(.atom)) |nlist, *atom| {
         if (!nlist.stab() and nlist.sect()) {
-            // if (sect.attrs() & macho.S_ATTR_DEBUG != 0) continue;
             if (self.findAtomInSection(nlist.n_value, nlist.n_sect - 1)) |atom_index| {
                 atom.* = atom_index;
             } else {