Commit `4f72ac265a`

Luuk de Gram <luuk@degram.dev>

2022-08-26 08:11:17

wasm: create relocations for extern decls

This also fixes performing relocations for data symbols of which the target symbol exists in an external object file. We do this by checking if the target symbol was discarded, and if so: get the new location so that we can find the corresponding atom that belongs to said new location. Previously it would always assume the symbol would live in the same file as the atom/symbol that is doing the relocation.

master

1 parent 414fcea

Changed files (2)

src

arch

wasm

CodeGen.zig

link

Wasm

Atom.zig

@@ -2355,7 +2355,7 @@ fn lowerDeclRefValue(self: *Self, tv: TypedValue, decl_index: Module.Decl.Index)
 
     const module = self.bin_file.base.options.module.?;
     const decl = module.declPtr(decl_index);
-    if (decl.ty.zigTypeTag() != .Fn and !decl.ty.hasRuntimeBitsIgnoreComptime()) {
+    if (!decl.ty.hasRuntimeBitsIgnoreComptime()) {
         return WValue{ .imm32 = 0xaaaaaaaa };
     }
 
@@ -2394,9 +2394,7 @@ fn lowerConstant(self: *Self, val: Value, ty: Type) InnerError!WValue {
         const decl_index = decl_ref_mut.data.decl_index;
         return self.lowerDeclRefValue(.{ .ty = ty, .val = val }, decl_index);
     }
-
     const target = self.target;
-
     switch (ty.zigTypeTag()) {
         .Void => return WValue{ .none = {} },
         .Int => {

@@ -174,13 +174,14 @@ fn relocationValue(self: Atom, relocation: types.Relocation, wasm_bin: *const Wa
         => {
             std.debug.assert(symbol.tag == .data and !symbol.isUndefined());
             const merge_segment = wasm_bin.base.options.output_mode != .Obj;
-            const segment_info = if (self.file) |object_index| blk: {
+            const target_atom_loc = wasm_bin.discarded.get(target_loc) orelse target_loc;
+            const target_atom = wasm_bin.symbol_atom.get(target_atom_loc).?;
+            const segment_info = if (target_atom.file) |object_index| blk: {
                 break :blk wasm_bin.objects.items[object_index].segment_info;
             } else wasm_bin.segment_info.items;
             const segment_name = segment_info[symbol.index].outputName(merge_segment);
-            const atom_index = wasm_bin.data_segments.get(segment_name).?;
-            const target_atom = wasm_bin.symbol_atom.get(target_loc).?;
-            const segment = wasm_bin.segments.items[atom_index];
+            const segment_index = wasm_bin.data_segments.get(segment_name).?;
+            const segment = wasm_bin.segments.items[segment_index];
             return target_atom.offset + segment.offset + (relocation.addend orelse 0);
         },
         .R_WASM_EVENT_INDEX_LEB => return symbol.index,

Commit 4f72ac265a

Commit `4f72ac265a`