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wasm-linker: remove synthetic segments & atoms

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Luuk de Gram 2023-03-10 06:20:10 +01:00
parent 87738cad86
commit 0ee9a52507
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1 changed files with 0 additions and 29 deletions
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29
src/link/Wasm.zig
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@ -887,32 +887,12 @@ fn resolveLazySymbols(wasm: *Wasm) !void {
const loc = try wasm.createSyntheticSymbol("__heap_base", .data);
try wasm.discarded.putNoClobber(wasm.base.allocator, kv.value, loc);
_ = wasm.resolved_symbols.swapRemove(loc); // we don't want to emit this symbol, only use it for relocations.
// TODO: Can we use `createAtom` here while also re-using the symbol
// from `createSyntheticSymbol`.
const atom_index = @intCast(Atom.Index, wasm.managed_atoms.items.len);
const atom = try wasm.managed_atoms.addOne(wasm.base.allocator);
atom.* = Atom.empty;
atom.sym_index = loc.index;
atom.alignment = 1;
try wasm.parseAtom(atom_index, .{ .data = .synthetic });
try wasm.symbol_atom.putNoClobber(wasm.base.allocator, loc, atom_index);
}
if (wasm.undefs.fetchSwapRemove("__heap_end")) |kv| {
const loc = try wasm.createSyntheticSymbol("__heap_end", .data);
try wasm.discarded.putNoClobber(wasm.base.allocator, kv.value, loc);
_ = wasm.resolved_symbols.swapRemove(loc);
const atom_index = @intCast(Atom.Index, wasm.managed_atoms.items.len);
const atom = try wasm.managed_atoms.addOne(wasm.base.allocator);
atom.* = Atom.empty;
atom.sym_index = loc.index;
atom.alignment = 1;
try wasm.parseAtom(atom_index, .{ .data = .synthetic });
try wasm.symbol_atom.putNoClobber(wasm.base.allocator, loc, atom_index);
}
}
@ -1614,7 +1594,6 @@ const Kind = union(enum) {
read_only,
uninitialized,
initialized,
synthetic,
},
function: void,
@ -1625,7 +1604,6 @@ const Kind = union(enum) {
.read_only => return ".rodata.",
.uninitialized => return ".bss.",
.initialized => return ".data.",
.synthetic => return ".synthetic",
}
}
};
@ -1833,7 +1811,6 @@ fn sortDataSegments(wasm: *Wasm) !void {
if (mem.startsWith(u8, name, ".rodata")) return 0;
if (mem.startsWith(u8, name, ".data")) return 1;
if (mem.startsWith(u8, name, ".text")) return 2;
if (mem.startsWith(u8, name, ".synthetic")) return 100; // always at end
return 3;
}
};
@ -2245,10 +2222,6 @@ fn setupMemory(wasm: *Wasm) !void {
var offset: u32 = @intCast(u32, memory_ptr);
var data_seg_it = wasm.data_segments.iterator();
while (data_seg_it.next()) |entry| {
if (mem.eql(u8, entry.key_ptr.*, ".synthetic")) {
// do not update synthetic segments as they are not part of the output
continue;
}
const segment = &wasm.segments.items[entry.value_ptr.*];
memory_ptr = std.mem.alignForwardGeneric(u64, memory_ptr, segment.alignment);
memory_ptr += segment.size;
@ -3447,8 +3420,6 @@ fn emitNameSection(wasm: *Wasm, binary_bytes: *std.ArrayList(u8), arena: std.mem
// bss section is not emitted when this condition holds true, so we also
// do not output a name for it.
if (!wasm.base.options.import_memory and std.mem.eql(u8, key, ".bss")) continue;
// Synthetic segments are not emitted
if (std.mem.eql(u8, key, ".synthetic")) continue;
segments.appendAssumeCapacity(.{ .index = data_segment_index, .name = key });
data_segment_index += 1;
}