diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/link/MachO.zig | 270 | ||||
| -rw-r--r-- | src/link/MachO/DebugSymbols.zig | 355 |
2 files changed, 342 insertions, 283 deletions
diff --git a/src/link/MachO.zig b/src/link/MachO.zig index 4cb0b016bc..2be7cb5199 100644 --- a/src/link/MachO.zig +++ b/src/link/MachO.zig @@ -11,8 +11,6 @@ const codegen = @import("../codegen.zig"); const aarch64 = @import("../codegen/aarch64.zig"); const math = std.math; const mem = std.mem; -const DW = std.dwarf; -const leb = std.leb; const trace = @import("../tracy.zig").trace; const build_options = @import("build_options"); @@ -1119,128 +1117,30 @@ pub fn updateDecl(self: *MachO, module: *Module, decl: *Module.Decl) !void { var code_buffer = std.ArrayList(u8).init(self.base.allocator); defer code_buffer.deinit(); - var dbg_line_buffer = std.ArrayList(u8).init(self.base.allocator); - defer dbg_line_buffer.deinit(); - - var dbg_info_buffer = std.ArrayList(u8).init(self.base.allocator); - defer dbg_info_buffer.deinit(); - - var dbg_info_type_relocs: File.DbgInfoTypeRelocsTable = .{}; + var debug_buffers = if (self.d_sym) |*ds| try ds.initDeclDebugBuffers(self.base.allocator, module, decl) else null; defer { - var it = dbg_info_type_relocs.iterator(); - while (it.next()) |entry| { - entry.value.relocs.deinit(self.base.allocator); + if (debug_buffers) |*dbg| { + dbg.dbg_line_buffer.deinit(); + dbg.dbg_info_buffer.deinit(); + var it = dbg.dbg_info_type_relocs.iterator(); + while (it.next()) |entry| { + entry.value.relocs.deinit(self.base.allocator); + } + dbg.dbg_info_type_relocs.deinit(self.base.allocator); } - dbg_info_type_relocs.deinit(self.base.allocator); } const typed_value = decl.typed_value.most_recent.typed_value; - const is_fn: bool = switch (typed_value.ty.zigTypeTag()) { - .Fn => true, - else => false, - }; - if (is_fn) { - const zir_dumps = if (std.builtin.is_test) &[0][]const u8{} else build_options.zir_dumps; - if (zir_dumps.len != 0) { - for (zir_dumps) |fn_name| { - if (mem.eql(u8, mem.spanZ(decl.name), fn_name)) { - std.debug.print("\n{}\n", .{decl.name}); - typed_value.val.cast(Value.Payload.Function).?.func.dump(module.*); - } - } - } - - // For functions we need to add a prologue to the debug line program. - try dbg_line_buffer.ensureCapacity(26); - - const line_off: u28 = blk: { - if (decl.scope.cast(Module.Scope.Container)) |container_scope| { - const tree = container_scope.file_scope.contents.tree; - const file_ast_decls = tree.root_node.decls(); - // TODO Look into improving the performance here by adding a token-index-to-line - // lookup table. Currently this involves scanning over the source code for newlines. - const fn_proto = file_ast_decls[decl.src_index].castTag(.FnProto).?; - const block = fn_proto.getBodyNode().?.castTag(.Block).?; - const line_delta = std.zig.lineDelta(tree.source, 0, tree.token_locs[block.lbrace].start); - break :blk @intCast(u28, line_delta); - } else if (decl.scope.cast(Module.Scope.ZIRModule)) |zir_module| { - const byte_off = zir_module.contents.module.decls[decl.src_index].inst.src; - const line_delta = std.zig.lineDelta(zir_module.source.bytes, 0, byte_off); - break :blk @intCast(u28, line_delta); - } else { - unreachable; - } - }; - - dbg_line_buffer.appendSliceAssumeCapacity(&[_]u8{ - DW.LNS_extended_op, - @sizeOf(u64) + 1, - DW.LNE_set_address, - }); - // This is the "relocatable" vaddr, corresponding to `code_buffer` index `0`. - assert(DebugSymbols.dbg_line_vaddr_reloc_index == dbg_line_buffer.items.len); - dbg_line_buffer.items.len += @sizeOf(u64); - - dbg_line_buffer.appendAssumeCapacity(DW.LNS_advance_line); - // This is the "relocatable" relative line offset from the previous function's end curly - // to this function's begin curly. - assert(DebugSymbols.getRelocDbgLineOff() == dbg_line_buffer.items.len); - // Here we use a ULEB128-fixed-4 to make sure this field can be overwritten later. - leb.writeUnsignedFixed(4, dbg_line_buffer.addManyAsArrayAssumeCapacity(4), line_off); - - dbg_line_buffer.appendAssumeCapacity(DW.LNS_set_file); - assert(DebugSymbols.getRelocDbgFileIndex() == dbg_line_buffer.items.len); - // Once we support more than one source file, this will have the ability to be more - // than one possible value. - const file_index = 1; - leb.writeUnsignedFixed(4, dbg_line_buffer.addManyAsArrayAssumeCapacity(4), file_index); - - // Emit a line for the begin curly with prologue_end=false. The codegen will - // do the work of setting prologue_end=true and epilogue_begin=true. - dbg_line_buffer.appendAssumeCapacity(DW.LNS_copy); - - // .debug_info subprogram - const decl_name_with_null = decl.name[0 .. mem.lenZ(decl.name) + 1]; - try dbg_info_buffer.ensureCapacity(dbg_info_buffer.items.len + 27 + decl_name_with_null.len); - - const fn_ret_type = typed_value.ty.fnReturnType(); - const fn_ret_has_bits = fn_ret_type.hasCodeGenBits(); - if (fn_ret_has_bits) { - dbg_info_buffer.appendAssumeCapacity(DebugSymbols.abbrev_subprogram); - } else { - dbg_info_buffer.appendAssumeCapacity(DebugSymbols.abbrev_subprogram_retvoid); - } - // These get overwritten after generating the machine code. These values are - // "relocations" and have to be in this fixed place so that functions can be - // moved in virtual address space. - assert(DebugSymbols.dbg_info_low_pc_reloc_index == dbg_info_buffer.items.len); - dbg_info_buffer.items.len += @sizeOf(u64); // DW.AT_low_pc, DW.FORM_addr - assert(DebugSymbols.getRelocDbgInfoSubprogramHighPC() == dbg_info_buffer.items.len); - dbg_info_buffer.items.len += 4; // DW.AT_high_pc, DW.FORM_data4 - if (fn_ret_has_bits) { - const gop = try dbg_info_type_relocs.getOrPut(self.base.allocator, fn_ret_type); - if (!gop.found_existing) { - gop.entry.value = .{ - .off = undefined, - .relocs = .{}, - }; - } - try gop.entry.value.relocs.append(self.base.allocator, @intCast(u32, dbg_info_buffer.items.len)); - dbg_info_buffer.items.len += 4; // DW.AT_type, DW.FORM_ref4 - } - dbg_info_buffer.appendSliceAssumeCapacity(decl_name_with_null); // DW.AT_name, DW.FORM_string - mem.writeIntLittle(u32, dbg_info_buffer.addManyAsArrayAssumeCapacity(4), line_off + 1); // DW.AT_decl_line, DW.FORM_data4 - dbg_info_buffer.appendAssumeCapacity(file_index); // DW.AT_decl_file, DW.FORM_data1 - } else { - // TODO implement .debug_info for global variables - } - const res = try codegen.generateSymbol(&self.base, decl.src(), typed_value, &code_buffer, .{ - .dwarf = .{ - .dbg_line = &dbg_line_buffer, - .dbg_info = &dbg_info_buffer, - .dbg_info_type_relocs = &dbg_info_type_relocs, - }, - }); + const res = if (debug_buffers) |*dbg| + try codegen.generateSymbol(&self.base, decl.src(), typed_value, &code_buffer, .{ + .dwarf = .{ + .dbg_line = &dbg.dbg_line_buffer, + .dbg_info = &dbg.dbg_info_buffer, + .dbg_info_type_relocs = &dbg.dbg_info_type_relocs, + }, + }) + else + try codegen.generateSymbol(&self.base, decl.src(), typed_value, &code_buffer, .none); const code = switch (res) { .externally_managed => |x| x, @@ -1328,132 +1228,16 @@ pub fn updateDecl(self: *MachO, module: *Module, decl: *Module.Decl) !void { const file_offset = text_section.offset + section_offset; try self.base.file.?.pwriteAll(code, file_offset); - const text_block = &decl.link.macho; - // If the Decl is a function, we need to update the __debug_line program. - if (is_fn) { - // Perform the relocations based on vaddr. - { - const ptr = dbg_line_buffer.items[DebugSymbols.dbg_line_vaddr_reloc_index..][0..8]; - mem.writeIntLittle(u64, ptr, symbol.n_value); - } - { - const ptr = dbg_info_buffer.items[DebugSymbols.dbg_info_low_pc_reloc_index..][0..8]; - mem.writeIntLittle(u64, ptr, symbol.n_value); - } - { - const ptr = dbg_info_buffer.items[DebugSymbols.getRelocDbgInfoSubprogramHighPC()..][0..4]; - mem.writeIntLittle(u32, ptr, @intCast(u32, text_block.size)); - } - - try dbg_line_buffer.appendSlice(&[_]u8{ DW.LNS_extended_op, 1, DW.LNE_end_sequence }); - - // Now we have the full contents and may allocate a region to store it. - - // This logic is nearly identical to the logic below in `updateDeclDebugInfo` for - // `TextBlock` and the .debug_info. If you are editing this logic, you - // probably need to edit that logic too. - - const dwarf_segment = &self.d_sym.?.load_commands.items[self.d_sym.?.dwarf_segment_cmd_index.?].Segment; - const debug_line_sect = &dwarf_segment.sections.items[self.d_sym.?.debug_line_section_index.?]; - const src_fn = &decl.fn_link.macho; - src_fn.len = @intCast(u32, dbg_line_buffer.items.len); - if (self.d_sym.?.dbg_line_fn_last) |last| { - if (src_fn.next) |next| { - // Update existing function - non-last item. - if (src_fn.off + src_fn.len + DebugSymbols.min_nop_size > next.off) { - // It grew too big, so we move it to a new location. - if (src_fn.prev) |prev| { - _ = self.d_sym.?.dbg_line_fn_free_list.put(self.base.allocator, prev, {}) catch {}; - prev.next = src_fn.next; - } - next.prev = src_fn.prev; - src_fn.next = null; - // Populate where it used to be with NOPs. - const file_pos = debug_line_sect.offset + src_fn.off; - try self.d_sym.?.pwriteDbgLineNops(0, &[0]u8{}, src_fn.len, file_pos); - // TODO Look at the free list before appending at the end. - src_fn.prev = last; - last.next = src_fn; - self.d_sym.?.dbg_line_fn_last = src_fn; - - src_fn.off = last.off + (last.len * alloc_num / alloc_den); - } - } else if (src_fn.prev == null) { - // Append new function. - // TODO Look at the free list before appending at the end. - src_fn.prev = last; - last.next = src_fn; - self.d_sym.?.dbg_line_fn_last = src_fn; - - src_fn.off = last.off + (last.len * alloc_num / alloc_den); - } - } else { - // This is the first function of the Line Number Program. - self.d_sym.?.dbg_line_fn_first = src_fn; - self.d_sym.?.dbg_line_fn_last = src_fn; - - src_fn.off = self.d_sym.?.dbgLineNeededHeaderBytes(module) * alloc_num / alloc_den; - } - - const last_src_fn = self.d_sym.?.dbg_line_fn_last.?; - const needed_size = last_src_fn.off + last_src_fn.len; - if (needed_size != debug_line_sect.size) { - if (needed_size > dwarf_segment.allocatedSize(debug_line_sect.offset)) { - const new_offset = dwarf_segment.findFreeSpace(needed_size, 1, null); - const existing_size = last_src_fn.off; - - log.debug("moving __debug_line section: {} bytes from 0x{x} to 0x{x}", .{ - existing_size, - debug_line_sect.offset, - new_offset, - }); - - const amt = try self.d_sym.?.file.copyRangeAll(debug_line_sect.offset, self.d_sym.?.file, new_offset, existing_size); - if (amt != existing_size) return error.InputOutput; - debug_line_sect.offset = @intCast(u32, new_offset); - debug_line_sect.addr = dwarf_segment.inner.vmaddr + new_offset - dwarf_segment.inner.fileoff; - } - debug_line_sect.size = needed_size; - self.d_sym.?.load_commands_dirty = true; // TODO look into making only the one section dirty - self.d_sym.?.debug_line_header_dirty = true; - } - const prev_padding_size: u32 = if (src_fn.prev) |prev| src_fn.off - (prev.off + prev.len) else 0; - const next_padding_size: u32 = if (src_fn.next) |next| next.off - (src_fn.off + src_fn.len) else 0; - - // We only have support for one compilation unit so far, so the offsets are directly - // from the .debug_line section. - const file_pos = debug_line_sect.offset + src_fn.off; - try self.d_sym.?.pwriteDbgLineNops(prev_padding_size, dbg_line_buffer.items, next_padding_size, file_pos); - - // .debug_info - End the TAG_subprogram children. - try dbg_info_buffer.append(0); - } - - // Now we emit the .debug_info types of the Decl. These will count towards the size of - // the buffer, so we have to do it before computing the offset, and we can't perform the actual - // relocations yet. - var it = dbg_info_type_relocs.iterator(); - while (it.next()) |entry| { - entry.value.off = @intCast(u32, dbg_info_buffer.items.len); - try self.d_sym.?.addDbgInfoType(entry.key, &dbg_info_buffer, self.base.options.target); - } - - try self.d_sym.?.updateDeclDebugInfoAllocation(self.base.allocator, text_block, @intCast(u32, dbg_info_buffer.items.len)); - - // Now that we have the offset assigned we can finally perform type relocations. - it = dbg_info_type_relocs.iterator(); - while (it.next()) |entry| { - for (entry.value.relocs.items) |off| { - mem.writeIntLittle( - u32, - dbg_info_buffer.items[off..][0..4], - text_block.dbg_info_off + entry.value.off, - ); - } + if (debug_buffers) |*db| { + try self.d_sym.?.commitDeclDebugInfo( + self.base.allocator, + module, + decl, + db, + self.base.options.target, + ); } - try self.d_sym.?.writeDeclDebugInfo(text_block, dbg_info_buffer.items); - // Since we updated the vaddr and the size, each corresponding export symbol also needs to be updated. const decl_exports = module.decl_exports.get(decl) orelse &[0]*Module.Export{}; try self.updateDeclExports(module, decl, decl_exports); diff --git a/src/link/MachO/DebugSymbols.zig b/src/link/MachO/DebugSymbols.zig index a6ac2dfde6..90f8cf9a00 100644 --- a/src/link/MachO/DebugSymbols.zig +++ b/src/link/MachO/DebugSymbols.zig @@ -10,6 +10,7 @@ const DW = std.dwarf; const leb = std.leb; const Allocator = mem.Allocator; +const build_options = @import("build_options"); const trace = @import("../../tracy.zig").trace; const Module = @import("../../Module.zig"); const Type = @import("../../type.zig").Type; @@ -87,21 +88,21 @@ debug_aranges_section_dirty: bool = false, debug_info_header_dirty: bool = false, debug_line_header_dirty: bool = false, -pub const abbrev_compile_unit = 1; -pub const abbrev_subprogram = 2; -pub const abbrev_subprogram_retvoid = 3; -pub const abbrev_base_type = 4; -pub const abbrev_pad1 = 5; -pub const abbrev_parameter = 6; +const abbrev_compile_unit = 1; +const abbrev_subprogram = 2; +const abbrev_subprogram_retvoid = 3; +const abbrev_base_type = 4; +const abbrev_pad1 = 5; +const abbrev_parameter = 6; /// The reloc offset for the virtual address of a function in its Line Number Program. /// Size is a virtual address integer. -pub const dbg_line_vaddr_reloc_index = 3; +const dbg_line_vaddr_reloc_index = 3; /// The reloc offset for the virtual address of a function in its .debug_info TAG_subprogram. /// Size is a virtual address integer. -pub const dbg_info_low_pc_reloc_index = 1; +const dbg_info_low_pc_reloc_index = 1; -pub const min_nop_size = 2; +const min_nop_size = 2; /// You must call this function *after* `MachO.populateMissingMetadata()` /// has been called to get a viable debug symbols output. @@ -888,8 +889,304 @@ fn writeStringTable(self: *DebugSymbols) !void { self.string_table_dirty = false; } +pub fn updateDeclLineNumber(self: *DebugSymbols, module: *Module, decl: *const Module.Decl) !void { + const tracy = trace(@src()); + defer tracy.end(); + + const container_scope = decl.scope.cast(Module.Scope.Container).?; + const tree = container_scope.file_scope.contents.tree; + const file_ast_decls = tree.root_node.decls(); + // TODO Look into improving the performance here by adding a token-index-to-line + // lookup table. Currently this involves scanning over the source code for newlines. + const fn_proto = file_ast_decls[decl.src_index].castTag(.FnProto).?; + const block = fn_proto.getBodyNode().?.castTag(.Block).?; + const line_delta = std.zig.lineDelta(tree.source, 0, tree.token_locs[block.lbrace].start); + const casted_line_off = @intCast(u28, line_delta); + + const dwarf_segment = &self.load_commands.items[self.dwarf_segment_cmd_index.?].Segment; + const shdr = &dwarf_segment.sections.items[self.debug_line_section_index.?]; + const file_pos = shdr.offset + decl.fn_link.macho.off + getRelocDbgLineOff(); + var data: [4]u8 = undefined; + leb.writeUnsignedFixed(4, &data, casted_line_off); + try self.file.pwriteAll(&data, file_pos); +} + +pub const DeclDebugBuffers = struct { + dbg_line_buffer: std.ArrayList(u8), + dbg_info_buffer: std.ArrayList(u8), + dbg_info_type_relocs: link.File.DbgInfoTypeRelocsTable, +}; + +/// Caller owns the returned memory. +pub fn initDeclDebugBuffers( + self: *DebugSymbols, + allocator: *Allocator, + module: *Module, + decl: *Module.Decl, +) !DeclDebugBuffers { + const tracy = trace(@src()); + defer tracy.end(); + + var dbg_line_buffer = std.ArrayList(u8).init(allocator); + var dbg_info_buffer = std.ArrayList(u8).init(allocator); + var dbg_info_type_relocs: link.File.DbgInfoTypeRelocsTable = .{}; + + const typed_value = decl.typed_value.most_recent.typed_value; + switch (typed_value.ty.zigTypeTag()) { + .Fn => { + const zir_dumps = if (std.builtin.is_test) &[0][]const u8{} else build_options.zir_dumps; + if (zir_dumps.len != 0) { + for (zir_dumps) |fn_name| { + if (mem.eql(u8, mem.spanZ(decl.name), fn_name)) { + std.debug.print("\n{}\n", .{decl.name}); + typed_value.val.cast(Value.Payload.Function).?.func.dump(module.*); + } + } + } + + // For functions we need to add a prologue to the debug line program. + try dbg_line_buffer.ensureCapacity(26); + + const line_off: u28 = blk: { + if (decl.scope.cast(Module.Scope.Container)) |container_scope| { + const tree = container_scope.file_scope.contents.tree; + const file_ast_decls = tree.root_node.decls(); + // TODO Look into improving the performance here by adding a token-index-to-line + // lookup table. Currently this involves scanning over the source code for newlines. + const fn_proto = file_ast_decls[decl.src_index].castTag(.FnProto).?; + const block = fn_proto.getBodyNode().?.castTag(.Block).?; + const line_delta = std.zig.lineDelta(tree.source, 0, tree.token_locs[block.lbrace].start); + break :blk @intCast(u28, line_delta); + } else if (decl.scope.cast(Module.Scope.ZIRModule)) |zir_module| { + const byte_off = zir_module.contents.module.decls[decl.src_index].inst.src; + const line_delta = std.zig.lineDelta(zir_module.source.bytes, 0, byte_off); + break :blk @intCast(u28, line_delta); + } else { + unreachable; + } + }; + + dbg_line_buffer.appendSliceAssumeCapacity(&[_]u8{ + DW.LNS_extended_op, + @sizeOf(u64) + 1, + DW.LNE_set_address, + }); + // This is the "relocatable" vaddr, corresponding to `code_buffer` index `0`. + assert(dbg_line_vaddr_reloc_index == dbg_line_buffer.items.len); + dbg_line_buffer.items.len += @sizeOf(u64); + + dbg_line_buffer.appendAssumeCapacity(DW.LNS_advance_line); + // This is the "relocatable" relative line offset from the previous function's end curly + // to this function's begin curly. + assert(getRelocDbgLineOff() == dbg_line_buffer.items.len); + // Here we use a ULEB128-fixed-4 to make sure this field can be overwritten later. + leb.writeUnsignedFixed(4, dbg_line_buffer.addManyAsArrayAssumeCapacity(4), line_off); + + dbg_line_buffer.appendAssumeCapacity(DW.LNS_set_file); + assert(getRelocDbgFileIndex() == dbg_line_buffer.items.len); + // Once we support more than one source file, this will have the ability to be more + // than one possible value. + const file_index = 1; + leb.writeUnsignedFixed(4, dbg_line_buffer.addManyAsArrayAssumeCapacity(4), file_index); + + // Emit a line for the begin curly with prologue_end=false. The codegen will + // do the work of setting prologue_end=true and epilogue_begin=true. + dbg_line_buffer.appendAssumeCapacity(DW.LNS_copy); + + // .debug_info subprogram + const decl_name_with_null = decl.name[0 .. mem.lenZ(decl.name) + 1]; + try dbg_info_buffer.ensureCapacity(dbg_info_buffer.items.len + 27 + decl_name_with_null.len); + + const fn_ret_type = typed_value.ty.fnReturnType(); + const fn_ret_has_bits = fn_ret_type.hasCodeGenBits(); + if (fn_ret_has_bits) { + dbg_info_buffer.appendAssumeCapacity(abbrev_subprogram); + } else { + dbg_info_buffer.appendAssumeCapacity(abbrev_subprogram_retvoid); + } + // These get overwritten after generating the machine code. These values are + // "relocations" and have to be in this fixed place so that functions can be + // moved in virtual address space. + assert(dbg_info_low_pc_reloc_index == dbg_info_buffer.items.len); + dbg_info_buffer.items.len += @sizeOf(u64); // DW.AT_low_pc, DW.FORM_addr + assert(getRelocDbgInfoSubprogramHighPC() == dbg_info_buffer.items.len); + dbg_info_buffer.items.len += 4; // DW.AT_high_pc, DW.FORM_data4 + if (fn_ret_has_bits) { + const gop = try dbg_info_type_relocs.getOrPut(allocator, fn_ret_type); + if (!gop.found_existing) { + gop.entry.value = .{ + .off = undefined, + .relocs = .{}, + }; + } + try gop.entry.value.relocs.append(allocator, @intCast(u32, dbg_info_buffer.items.len)); + dbg_info_buffer.items.len += 4; // DW.AT_type, DW.FORM_ref4 + } + dbg_info_buffer.appendSliceAssumeCapacity(decl_name_with_null); // DW.AT_name, DW.FORM_string + mem.writeIntLittle(u32, dbg_info_buffer.addManyAsArrayAssumeCapacity(4), line_off + 1); // DW.AT_decl_line, DW.FORM_data4 + dbg_info_buffer.appendAssumeCapacity(file_index); // DW.AT_decl_file, DW.FORM_data1 + }, + else => { + // TODO implement .debug_info for global variables + }, + } + + return DeclDebugBuffers{ + .dbg_info_buffer = dbg_info_buffer, + .dbg_line_buffer = dbg_line_buffer, + .dbg_info_type_relocs = dbg_info_type_relocs, + }; +} + +pub fn commitDeclDebugInfo( + self: *DebugSymbols, + allocator: *Allocator, + module: *Module, + decl: *Module.Decl, + debug_buffers: *DeclDebugBuffers, + target: std.Target, +) !void { + const tracy = trace(@src()); + defer tracy.end(); + + var dbg_line_buffer = &debug_buffers.dbg_line_buffer; + var dbg_info_buffer = &debug_buffers.dbg_info_buffer; + var dbg_info_type_relocs = &debug_buffers.dbg_info_type_relocs; + + const symbol = self.base.local_symbols.items[decl.link.macho.local_sym_index]; + const text_block = &decl.link.macho; + // If the Decl is a function, we need to update the __debug_line program. + const typed_value = decl.typed_value.most_recent.typed_value; + switch (typed_value.ty.zigTypeTag()) { + .Fn => { + // Perform the relocations based on vaddr. + { + const ptr = dbg_line_buffer.items[dbg_line_vaddr_reloc_index..][0..8]; + mem.writeIntLittle(u64, ptr, symbol.n_value); + } + { + const ptr = dbg_info_buffer.items[dbg_info_low_pc_reloc_index..][0..8]; + mem.writeIntLittle(u64, ptr, symbol.n_value); + } + { + const ptr = dbg_info_buffer.items[getRelocDbgInfoSubprogramHighPC()..][0..4]; + mem.writeIntLittle(u32, ptr, @intCast(u32, text_block.size)); + } + + try dbg_line_buffer.appendSlice(&[_]u8{ DW.LNS_extended_op, 1, DW.LNE_end_sequence }); + + // Now we have the full contents and may allocate a region to store it. + + // This logic is nearly identical to the logic below in `updateDeclDebugInfo` for + // `TextBlock` and the .debug_info. If you are editing this logic, you + // probably need to edit that logic too. + + const dwarf_segment = &self.load_commands.items[self.dwarf_segment_cmd_index.?].Segment; + const debug_line_sect = &dwarf_segment.sections.items[self.debug_line_section_index.?]; + const src_fn = &decl.fn_link.macho; + src_fn.len = @intCast(u32, dbg_line_buffer.items.len); + if (self.dbg_line_fn_last) |last| { + if (src_fn.next) |next| { + // Update existing function - non-last item. + if (src_fn.off + src_fn.len + min_nop_size > next.off) { + // It grew too big, so we move it to a new location. + if (src_fn.prev) |prev| { + _ = self.dbg_line_fn_free_list.put(allocator, prev, {}) catch {}; + prev.next = src_fn.next; + } + next.prev = src_fn.prev; + src_fn.next = null; + // Populate where it used to be with NOPs. + const file_pos = debug_line_sect.offset + src_fn.off; + try self.pwriteDbgLineNops(0, &[0]u8{}, src_fn.len, file_pos); + // TODO Look at the free list before appending at the end. + src_fn.prev = last; + last.next = src_fn; + self.dbg_line_fn_last = src_fn; + + src_fn.off = last.off + (last.len * alloc_num / alloc_den); + } + } else if (src_fn.prev == null) { + // Append new function. + // TODO Look at the free list before appending at the end. + src_fn.prev = last; + last.next = src_fn; + self.dbg_line_fn_last = src_fn; + + src_fn.off = last.off + (last.len * alloc_num / alloc_den); + } + } else { + // This is the first function of the Line Number Program. + self.dbg_line_fn_first = src_fn; + self.dbg_line_fn_last = src_fn; + + src_fn.off = self.dbgLineNeededHeaderBytes(module) * alloc_num / alloc_den; + } + + const last_src_fn = self.dbg_line_fn_last.?; + const needed_size = last_src_fn.off + last_src_fn.len; + if (needed_size != debug_line_sect.size) { + if (needed_size > dwarf_segment.allocatedSize(debug_line_sect.offset)) { + const new_offset = dwarf_segment.findFreeSpace(needed_size, 1, null); + const existing_size = last_src_fn.off; + + log.debug("moving __debug_line section: {} bytes from 0x{x} to 0x{x}", .{ + existing_size, + debug_line_sect.offset, + new_offset, + }); + + const amt = try self.file.copyRangeAll(debug_line_sect.offset, self.file, new_offset, existing_size); + if (amt != existing_size) return error.InputOutput; + debug_line_sect.offset = @intCast(u32, new_offset); + debug_line_sect.addr = dwarf_segment.inner.vmaddr + new_offset - dwarf_segment.inner.fileoff; + } + debug_line_sect.size = needed_size; + self.load_commands_dirty = true; // TODO look into making only the one section dirty + self.debug_line_header_dirty = true; + } + const prev_padding_size: u32 = if (src_fn.prev) |prev| src_fn.off - (prev.off + prev.len) else 0; + const next_padding_size: u32 = if (src_fn.next) |next| next.off - (src_fn.off + src_fn.len) else 0; + + // We only have support for one compilation unit so far, so the offsets are directly + // from the .debug_line section. + const file_pos = debug_line_sect.offset + src_fn.off; + try self.pwriteDbgLineNops(prev_padding_size, dbg_line_buffer.items, next_padding_size, file_pos); + + // .debug_info - End the TAG_subprogram children. + try dbg_info_buffer.append(0); + }, + else => {}, + } + + // Now we emit the .debug_info types of the Decl. These will count towards the size of + // the buffer, so we have to do it before computing the offset, and we can't perform the actual + // relocations yet. + var it = dbg_info_type_relocs.iterator(); + while (it.next()) |entry| { + entry.value.off = @intCast(u32, dbg_info_buffer.items.len); + try self.addDbgInfoType(entry.key, dbg_info_buffer, target); + } + + try self.updateDeclDebugInfoAllocation(allocator, text_block, @intCast(u32, dbg_info_buffer.items.len)); + + // Now that we have the offset assigned we can finally perform type relocations. + it = dbg_info_type_relocs.iterator(); + while (it.next()) |entry| { + for (entry.value.relocs.items) |off| { + mem.writeIntLittle( + u32, + dbg_info_buffer.items[off..][0..4], + text_block.dbg_info_off + entry.value.off, + ); + } + } + + try self.writeDeclDebugInfo(text_block, dbg_info_buffer.items); +} + /// Asserts the type has codegen bits. -pub fn addDbgInfoType( +fn addDbgInfoType( self: *DebugSymbols, ty: Type, dbg_info_buffer: *std.ArrayList(u8), @@ -931,7 +1228,7 @@ pub fn addDbgInfoType( } } -pub fn updateDeclDebugInfoAllocation( +fn updateDeclDebugInfoAllocation( self: *DebugSymbols, allocator: *Allocator, text_block: *TextBlock, @@ -986,7 +1283,7 @@ pub fn updateDeclDebugInfoAllocation( } } -pub fn writeDeclDebugInfo(self: *DebugSymbols, text_block: *TextBlock, dbg_info_buf: []const u8) !void { +fn writeDeclDebugInfo(self: *DebugSymbols, text_block: *TextBlock, dbg_info_buf: []const u8) !void { const tracy = trace(@src()); defer tracy.end(); @@ -1057,19 +1354,19 @@ fn makeDebugString(self: *DebugSymbols, allocator: *Allocator, bytes: []const u8 /// The reloc offset for the line offset of a function from the previous function's line. /// It's a fixed-size 4-byte ULEB128. -pub fn getRelocDbgLineOff() usize { +fn getRelocDbgLineOff() usize { return dbg_line_vaddr_reloc_index + @sizeOf(u64) + 1; } -pub fn getRelocDbgFileIndex() usize { +fn getRelocDbgFileIndex() usize { return getRelocDbgLineOff() + 5; } -pub fn getRelocDbgInfoSubprogramHighPC() u32 { +fn getRelocDbgInfoSubprogramHighPC() u32 { return dbg_info_low_pc_reloc_index + @sizeOf(u64); } -pub fn dbgLineNeededHeaderBytes(self: DebugSymbols, module: *Module) u32 { +fn dbgLineNeededHeaderBytes(self: DebugSymbols, module: *Module) u32 { const directory_entry_format_count = 1; const file_name_entry_format_count = 1; const directory_count = 1; @@ -1092,7 +1389,7 @@ fn dbgInfoNeededHeaderBytes(self: DebugSymbols) u32 { /// are less than 126,976 bytes (if this limit is ever reached, this function can be /// improved to make more than one pwritev call, or the limit can be raised by a fixed /// amount by increasing the length of `vecs`). -pub fn pwriteDbgLineNops( +fn pwriteDbgLineNops( self: *DebugSymbols, prev_padding_size: usize, buf: []const u8, @@ -1170,7 +1467,7 @@ pub fn pwriteDbgLineNops( /// Writes to the file a buffer, prefixed and suffixed by the specified number of /// bytes of padding. -pub fn pwriteDbgInfoNops( +fn pwriteDbgInfoNops( self: *DebugSymbols, prev_padding_size: usize, buf: []const u8, @@ -1239,25 +1536,3 @@ pub fn pwriteDbgInfoNops( try self.file.pwritevAll(vecs[0..vec_index], offset - prev_padding_size); } - -pub fn updateDeclLineNumber(self: *DebugSymbols, module: *Module, decl: *const Module.Decl) !void { - const tracy = trace(@src()); - defer tracy.end(); - - const container_scope = decl.scope.cast(Module.Scope.Container).?; - const tree = container_scope.file_scope.contents.tree; - const file_ast_decls = tree.root_node.decls(); - // TODO Look into improving the performance here by adding a token-index-to-line - // lookup table. Currently this involves scanning over the source code for newlines. - const fn_proto = file_ast_decls[decl.src_index].castTag(.FnProto).?; - const block = fn_proto.getBodyNode().?.castTag(.Block).?; - const line_delta = std.zig.lineDelta(tree.source, 0, tree.token_locs[block.lbrace].start); - const casted_line_off = @intCast(u28, line_delta); - - const dwarf_segment = &self.load_commands.items[self.dwarf_segment_cmd_index.?].Segment; - const shdr = &dwarf_segment.sections.items[self.debug_line_section_index.?]; - const file_pos = shdr.offset + decl.fn_link.macho.off + getRelocDbgLineOff(); - var data: [4]u8 = undefined; - leb.writeUnsignedFixed(4, &data, casted_line_off); - try self.file.pwriteAll(&data, file_pos); -} |