Merge pull request #21681 from ziglang/reduce-flush

link.Elf: eliminate an O(N^2) algorithm in flush()
ziglang · Oct 12, 2024 · f7c5882 · f7c5882
2 parents 7e530c1 + de04a8a
commit f7c5882
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Showing 20 changed files with 806 additions and 740 deletions.
diff --git a/lib/compiler/objcopy.zig b/lib/compiler/objcopy.zig
@@ -832,7 +832,6 @@ fn ElfFile(comptime is_64: bool) type {
     const Elf_Shdr = if (is_64) elf.Elf64_Shdr else elf.Elf32_Shdr;
     const Elf_Chdr = if (is_64) elf.Elf64_Chdr else elf.Elf32_Chdr;
     const Elf_Sym = if (is_64) elf.Elf64_Sym else elf.Elf32_Sym;
-    const Elf_Verdef = if (is_64) elf.Elf64_Verdef else elf.Elf32_Verdef;
     const Elf_OffSize = if (is_64) elf.Elf64_Off else elf.Elf32_Off;
 
     return struct {
@@ -1179,11 +1178,11 @@ fn ElfFile(comptime is_64: bool) type {
                                     const data = try allocator.alignedAlloc(u8, section_memory_align, src_data.len);
                                     @memcpy(data, src_data);
 
-                                    const defs = @as([*]Elf_Verdef, @ptrCast(data))[0 .. @as(usize, @intCast(src.sh_size)) / @sizeOf(Elf_Verdef)];
-                                    for (defs) |*def| {
-                                        if (def.vd_ndx != elf.SHN_UNDEF)
-                                            def.vd_ndx = sections_update[src.sh_info].remap_idx;
-                                    }
+                                    const defs = @as([*]elf.Verdef, @ptrCast(data))[0 .. @as(usize, @intCast(src.sh_size)) / @sizeOf(elf.Verdef)];
+                                    for (defs) |*def| switch (def.ndx) {
+                                        .LOCAL, .GLOBAL => {},
+                                        else => def.ndx = @enumFromInt(sections_update[src.sh_info].remap_idx),
+                                    };
 
                                     break :dst_data data;
                                 },

diff --git a/lib/std/Build/Cache.zig b/lib/std/Build/Cache.zig
@@ -150,6 +150,14 @@ pub const File = struct {
         inode: fs.File.INode,
         size: u64,
         mtime: i128,
+
+        pub fn fromFs(fs_stat: fs.File.Stat) Stat {
+            return .{
+                .inode = fs_stat.inode,
+                .size = fs_stat.size,
+                .mtime = fs_stat.mtime,
+            };
+        }
     };
 
     pub fn deinit(self: *File, gpa: Allocator) void {

diff --git a/lib/std/dynamic_library.zig b/lib/std/dynamic_library.zig
@@ -141,7 +141,7 @@ pub const ElfDynLib = struct {
     strings: [*:0]u8,
     syms: [*]elf.Sym,
     hashtab: [*]posix.Elf_Symndx,
-    versym: ?[*]u16,
+    versym: ?[*]elf.Versym,
     verdef: ?*elf.Verdef,
     memory: []align(mem.page_size) u8,
 
@@ -319,19 +319,19 @@ pub const ElfDynLib = struct {
         var maybe_strings: ?[*:0]u8 = null;
         var maybe_syms: ?[*]elf.Sym = null;
         var maybe_hashtab: ?[*]posix.Elf_Symndx = null;
-        var maybe_versym: ?[*]u16 = null;
+        var maybe_versym: ?[*]elf.Versym = null;
         var maybe_verdef: ?*elf.Verdef = null;
 
         {
             var i: usize = 0;
             while (dynv[i] != 0) : (i += 2) {
                 const p = base + dynv[i + 1];
                 switch (dynv[i]) {
-                    elf.DT_STRTAB => maybe_strings = @as([*:0]u8, @ptrFromInt(p)),
-                    elf.DT_SYMTAB => maybe_syms = @as([*]elf.Sym, @ptrFromInt(p)),
-                    elf.DT_HASH => maybe_hashtab = @as([*]posix.Elf_Symndx, @ptrFromInt(p)),
-                    elf.DT_VERSYM => maybe_versym = @as([*]u16, @ptrFromInt(p)),
-                    elf.DT_VERDEF => maybe_verdef = @as(*elf.Verdef, @ptrFromInt(p)),
+                    elf.DT_STRTAB => maybe_strings = @ptrFromInt(p),
+                    elf.DT_SYMTAB => maybe_syms = @ptrFromInt(p),
+                    elf.DT_HASH => maybe_hashtab = @ptrFromInt(p),
+                    elf.DT_VERSYM => maybe_versym = @ptrFromInt(p),
+                    elf.DT_VERDEF => maybe_verdef = @ptrFromInt(p),
                     else => {},
                 }
             }
@@ -399,18 +399,16 @@ pub const ElfDynLib = struct {
     }
 };
 
-fn checkver(def_arg: *elf.Verdef, vsym_arg: i32, vername: []const u8, strings: [*:0]u8) bool {
+fn checkver(def_arg: *elf.Verdef, vsym_arg: elf.Versym, vername: []const u8, strings: [*:0]u8) bool {
     var def = def_arg;
-    const vsym = @as(u32, @bitCast(vsym_arg)) & 0x7fff;
+    const vsym_index = vsym_arg.VERSION;
     while (true) {
-        if (0 == (def.vd_flags & elf.VER_FLG_BASE) and (def.vd_ndx & 0x7fff) == vsym)
-            break;
-        if (def.vd_next == 0)
-            return false;
-        def = @as(*elf.Verdef, @ptrFromInt(@intFromPtr(def) + def.vd_next));
+        if (0 == (def.flags & elf.VER_FLG_BASE) and @intFromEnum(def.ndx) == vsym_index) break;
+        if (def.next == 0) return false;
+        def = @ptrFromInt(@intFromPtr(def) + def.next);
     }
-    const aux = @as(*elf.Verdaux, @ptrFromInt(@intFromPtr(def) + def.vd_aux));
-    return mem.eql(u8, vername, mem.sliceTo(strings + aux.vda_name, 0));
+    const aux: *elf.Verdaux = @ptrFromInt(@intFromPtr(def) + def.aux);
+    return mem.eql(u8, vername, mem.sliceTo(strings + aux.name, 0));
 }
 
 test "ElfDynLib" {