Merge pull request #9831 from mathetake/llvmvisibility

Stage1: Add Visibility field to ExportOptions.

lib/std/builtin.zig

@@ -68,6 +68,14 @@ pub const GlobalLinkage = enum {
     LinkOnce,
 };
 
+/// This data structure is used by the Zig language code generation and
+/// therefore must be kept in sync with the compiler implementation.
+pub const SymbolVisibility = enum {
+    default,
+    hidden,
+    protected,
+};
+
 /// This data structure is used by the Zig language code generation and
 /// therefore must be kept in sync with the compiler implementation.
 pub const AtomicOrder = enum {
@@ -655,6 +663,7 @@ pub const ExportOptions = struct {
     name: []const u8,
     linkage: GlobalLinkage = .Strong,
     section: ?[]const u8 = null,
+    visibility: SymbolVisibility = .default,
 };
 
 /// This data structure is used by the Zig language code generation and

src/Sema.zig

@@ -4348,6 +4348,7 @@ pub fn analyzeExport(
             .name = symbol_name,
             .linkage = borrowed_options.linkage,
             .section = section,
+            .visibility = borrowed_options.visibility,
         },
         .src = src,
         .link = switch (mod.comp.bin_file.tag) {
@@ -14998,23 +14999,37 @@ fn resolveExportOptions(
     const air_ref = sema.resolveInst(zir_ref);
     const options = try sema.coerce(block, export_options_ty, air_ref, src);
 
-    const name = try sema.fieldVal(block, src, options, "name", src);
-    const name_val = try sema.resolveConstValue(block, src, name);
+    const name_operand = try sema.fieldVal(block, src, options, "name", src);
+    const name_val = try sema.resolveConstValue(block, src, name_operand);
+    const name_ty = Type.initTag(.const_slice_u8);
+    const name = try name_val.toAllocatedBytes(name_ty, sema.arena, sema.mod);
 
-    const linkage = try sema.fieldVal(block, src, options, "linkage", src);
-    const linkage_val = try sema.resolveConstValue(block, src, linkage);
+    const linkage_operand = try sema.fieldVal(block, src, options, "linkage", src);
+    const linkage_val = try sema.resolveConstValue(block, src, linkage_operand);
+    const linkage = linkage_val.toEnum(std.builtin.GlobalLinkage);
 
     const section = try sema.fieldVal(block, src, options, "section", src);
     const section_val = try sema.resolveConstValue(block, src, section);
 
+    const visibility_operand = try sema.fieldVal(block, src, options, "visibility", src);
+    const visibility_val = try sema.resolveConstValue(block, src, visibility_operand);
+    const visibility = visibility_val.toEnum(std.builtin.SymbolVisibility);
+
+    if (visibility != .default and linkage == .Internal) {
+        return sema.fail(block, src, "symbol '{s}' exported with internal linkage has non-default visibility {s}", .{
+            name, @tagName(visibility),
+        });
+    }
+
     if (!section_val.isNull()) {
         return sema.fail(block, src, "TODO: implement exporting with linksection", .{});
     }
-    const name_ty = Type.initTag(.const_slice_u8);
+
     return std.builtin.ExportOptions{
-        .name = try name_val.toAllocatedBytes(name_ty, sema.arena, sema.mod),
-        .linkage = linkage_val.toEnum(std.builtin.GlobalLinkage),
+        .name = name,
+        .linkage = linkage,
         .section = null, // TODO
+        .visibility = visibility,
     };
 }
 

src/codegen/llvm.zig

@@ -808,6 +808,11 @@ pub const Object = struct {
                 .Weak => llvm_global.setLinkage(.WeakODR),
                 .LinkOnce => llvm_global.setLinkage(.LinkOnceODR),
             }
+            switch (exports[0].options.visibility) {
+                .default => llvm_global.setVisibility(.Default),
+                .hidden => llvm_global.setVisibility(.Hidden),
+                .protected => llvm_global.setVisibility(.Protected),
+            }
             if (decl.val.castTag(.variable)) |variable| {
                 if (variable.data.is_threadlocal) {
                     llvm_global.setThreadLocalMode(.GeneralDynamicTLSModel);

src/codegen/llvm/bindings.zig

@@ -117,6 +117,9 @@ pub const Value = opaque {
     pub const setLinkage = LLVMSetLinkage;
     extern fn LLVMSetLinkage(Global: *const Value, Linkage: Linkage) void;
 
+    pub const setVisibility = LLVMSetVisibility;
+    extern fn LLVMSetVisibility(Global: *const Value, Linkage: Visibility) void;
+
     pub const setUnnamedAddr = LLVMSetUnnamedAddr;
     extern fn LLVMSetUnnamedAddr(Global: *const Value, HasUnnamedAddr: Bool) void;
 
@@ -1324,6 +1327,12 @@ pub const Linkage = enum(c_uint) {
     LinkerPrivateWeak,
 };
 
+pub const Visibility = enum(c_uint) {
+    Default,
+    Hidden,
+    Protected,
+};
+
 pub const ThreadLocalMode = enum(c_uint) {
     NotThreadLocal,
     GeneralDynamicTLSModel,