[lld] a499898 - [lld-macho] Generate ObjC symbols from .tbd files

[Jez Ng via llvm-commits]

Author: Jez Ng
Date: 2020-08-12T19:50:10-07:00
New Revision: a499898e86ec322ed47b43aaabdd3fedbf58840a

URL: https://github.com/llvm/llvm-project/commit/a499898e86ec322ed47b43aaabdd3fedbf58840a
DIFF: https://github.com/llvm/llvm-project/commit/a499898e86ec322ed47b43aaabdd3fedbf58840a.diff

LOG: [lld-macho] Generate ObjC symbols from .tbd files

I followed similar logic in TapiFile.cpp.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D85255

Added: 
    

Modified: 
    lld/MachO/InputFiles.cpp
    lld/test/MachO/Inputs/MacOSX.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation.tbd
    lld/test/MachO/stub-link.s

Removed: 
    


################################################################################
diff  --git a/lld/MachO/InputFiles.cpp b/lld/MachO/InputFiles.cpp
index 5df42b358203..03573868146e 100644
--- a/lld/MachO/InputFiles.cpp
+++ b/lld/MachO/InputFiles.cpp
@@ -403,13 +403,35 @@ DylibFile::DylibFile(std::shared_ptr<llvm::MachO::InterfaceFile> interface,
     umbrella = this;
 
   dylibName = saver.save(interface->getInstallName());
+  auto addSymbol = [&](const Twine &name) -> void {
+    symbols.push_back(symtab->addDylib(saver.save(name), umbrella,
+                                       /*isWeakDef=*/false,
+                                       /*isTlv=*/false));
+  };
   // TODO(compnerd) filter out symbols based on the target platform
   // TODO: handle weak defs, thread locals
-  for (const auto symbol : interface->symbols())
-    if (symbol->getArchitectures().has(config->arch))
-      symbols.push_back(symtab->addDylib(saver.save(symbol->getName()),
-                                         umbrella, /*isWeakDef=*/false,
-                                         /*isTlv=*/false));
+  for (const auto symbol : interface->symbols()) {
+    if (!symbol->getArchitectures().has(config->arch))
+      continue;
+
+    switch (symbol->getKind()) {
+    case SymbolKind::GlobalSymbol:
+      addSymbol(symbol->getName());
+      break;
+    case SymbolKind::ObjectiveCClass:
+      // XXX ld64 only creates these symbols when -ObjC is passed in. We may
+      // want to emulate that.
+      addSymbol("_OBJC_CLASS_$_" + symbol->getName());
+      addSymbol("_OBJC_METACLASS_$_" + symbol->getName());
+      break;
+    case SymbolKind::ObjectiveCClassEHType:
+      addSymbol("_OBJC_EHTYPE_$_" + symbol->getName());
+      break;
+    case SymbolKind::ObjectiveCInstanceVariable:
+      addSymbol("_OBJC_IVAR_$_" + symbol->getName());
+      break;
+    }
+  }
   // TODO(compnerd) properly represent the hierarchy of the documents as it is
   // in theory possible to have re-exported dylibs from re-exported dylibs which
   // should be parent'ed to the child.

diff  --git a/lld/test/MachO/Inputs/MacOSX.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation.tbd b/lld/test/MachO/Inputs/MacOSX.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation.tbd
index d9c6245b8033..ef122e667281 100644
--- a/lld/test/MachO/Inputs/MacOSX.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation.tbd
+++ b/lld/test/MachO/Inputs/MacOSX.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation.tbd
@@ -6,5 +6,8 @@ install-name:     '/System/Library/Frameworks/CoreFoundation.framework/CoreFound
 current-version:  0001.001.1
 compatibility-version: 150
 exports:
-  - archs:        [ 'x86_64' ]
-    symbols:      [ '__CFBigNumGetInt128' ]
+  - archs:         [ 'x86_64' ]
+    symbols:       [ '__CFBigNumGetInt128' ]
+    objc-classes:  [ NSObject ]
+    objc-ivars:    [ NSConstantArray._count ]
+    objc-eh-types: [ NSException ]

diff  --git a/lld/test/MachO/stub-link.s b/lld/test/MachO/stub-link.s
index 1bf65c46a787..0d6b7fec3f2a 100644
--- a/lld/test/MachO/stub-link.s
+++ b/lld/test/MachO/stub-link.s
@@ -3,7 +3,7 @@
 # RUN: mkdir -p %t
 #
 # RUN: llvm-mc -filetype obj -triple x86_64-apple-darwin %s -o %t/test.o
-# RUN: lld -flavor darwinnew -o %t/test -Z -L%S/Inputs/MacOSX.sdk/usr/lib -lSystem %t/test.o
+# RUN: lld -flavor darwinnew -o %t/test -syslibroot %S/Inputs/MacOSX.sdk -lSystem -framework CoreFoundation %t/test.o
 #
 # RUN: llvm-objdump --bind --no-show-raw-insn -d -r %t/test | FileCheck %s
 
@@ -11,7 +11,11 @@
 # CHECK: movq {{.*}} # [[ADDR:[0-9a-f]+]]
 
 # CHECK: Bind table:
-# CHECK: __DATA_CONST __got 0x[[ADDR]] pointer 0 libSystem ___nan
+# CHECK-DAG: __DATA_CONST __got 0x[[ADDR]] pointer 0 libSystem ___nan
+# CHECK-DAG: __DATA __data {{.*}} pointer 0 CoreFoundation _OBJC_CLASS_$_NSObject
+# CHECK-DAG: __DATA __data {{.*}} pointer 0 CoreFoundation _OBJC_METACLASS_$_NSObject
+# CHECK-DAG: __DATA __data {{.*}} pointer 0 CoreFoundation _OBJC_IVAR_$_NSConstantArray._count
+# CHECK-DAG: __DATA __data {{.*}} pointer 0 CoreFoundation _OBJC_EHTYPE_$_NSException
 
 .section __TEXT,__text
 .global _main
@@ -19,3 +23,9 @@
 _main:
   movq ___nan at GOTPCREL(%rip), %rax
   ret
+
+.data
+  .quad _OBJC_CLASS_$_NSObject
+  .quad _OBJC_METACLASS_$_NSObject
+  .quad _OBJC_IVAR_$_NSConstantArray._count
+  .quad _OBJC_EHTYPE_$_NSException