[llvm][Object] set SF_Hidden flag for MachO files

Reviewed By: pete, ributzka

Differential Revision: https://reviews.llvm.org/D139862

(cherry picked from commit ac20a3a)

Author: cyndyishida

lld/test/MachO/alias-symbols.s

@@ -15,10 +15,10 @@
 
 # CHECK-DAG: [[#%.16x,STRONG:]] g     F __TEXT,__text _strong
 # CHECK-DAG: [[#%.16x,WEAK_1:]]  w    F __TEXT,__text _weak_1
-# CHECK-DAG: [[#%.16x,PEXT:]]   l     F __TEXT,__text _pext
+# CHECK-DAG: [[#%.16x,PEXT:]]   l     F __TEXT,__text .hidden _pext
 # CHECK-DAG: [[#%.16x,DEAD:]]   g     F __TEXT,__text _dead
-# CHECK-DAG: [[#STRONG]]        l     F __TEXT,__text _pext_alias
-# CHECK-DAG: [[#PEXT]]          l     F __TEXT,__text _alias_to_pext
+# CHECK-DAG: [[#STRONG]]        l     F __TEXT,__text .hidden _pext_alias
+# CHECK-DAG: [[#PEXT]]          l     F __TEXT,__text .hidden _alias_to_pext
 # CHECK-DAG: [[#STRONG]]        g     F __TEXT,__text _extern_alias_to_strong
 # CHECK-DAG: [[#WEAK_1]]         w    F __TEXT,__text _weak_extern_alias_to_weak
 # CHECK-DAG: [[#DEAD]]          g     F __TEXT,__text _no_dead_strip_alias

lld/test/MachO/lto-explicit-exports.ll

@@ -46,7 +46,7 @@
 ; THINLTO-REFS-FOO: declare dso_local void @foo()
 ; THINLTO-REFS-FOO: define dso_local void @refs_foo()
 
-; THINLTO-SYMS: l     F __TEXT,__text _foo
+; THINLTO-SYMS: l     F __TEXT,__text .hidden _foo
 ; THINLTO-SYMS: g     F __TEXT,__text _same_module_caller
 ; THINLTO-SYMS: g     F __TEXT,__text _refs_foo
 

lld/test/MachO/weak-definition-gc.s

@@ -70,10 +70,10 @@
 # RUN: %lld -o %t/out -lSystem %t/weak-aligned-1.o %t/weak-aligned-2.o -dead_strip
 # RUN: llvm-objdump --syms --section=__const --full-contents %t/out | FileCheck --check-prefixes=ALIGN,ALIGN3 %s
 # ALIGN:       SYMBOL TABLE:
-# ALIGN-DAG:   [[#%x, ADDR:]]       l     O __DATA_CONST,__const _weak1
-# ALIGN2-DAG:  {{0*}}[[#ADDR+ 0x4]] l     O __DATA_CONST,__const _weak3
-# ALIGN3-DAG:  {{0*}}[[#ADDR+ 0x4]] l     O __DATA_CONST,__const _weak2
-# ALIGN2-DAG:  {{0*}}[[#ADDR+ 0x8]] l     O __DATA_CONST,__const _weak2
+# ALIGN-DAG:   [[#%x, ADDR:]]       l     O __DATA_CONST,__const .hidden _weak1
+# ALIGN2-DAG:  {{0*}}[[#ADDR+ 0x4]] l     O __DATA_CONST,__const .hidden _weak3
+# ALIGN3-DAG:  {{0*}}[[#ADDR+ 0x4]] l     O __DATA_CONST,__const .hidden _weak2
+# ALIGN2-DAG:  {{0*}}[[#ADDR+ 0x8]] l     O __DATA_CONST,__const .hidden _weak2
 # ALIGN-DAG:   {{0*}}[[#ADDR+0x10]] g     O __DATA_CONST,__const _aligned
 # ALIGN:       Contents of section __DATA_CONST,__const:
 # ALIGN2-NEXT: {{0*}}[[#ADDR]]      11111111 33333333 22222222 00000000

llvm/lib/Object/MachOObjectFile.cpp

@@ -1876,9 +1876,13 @@ Expected<uint32_t> MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
         Result |= SymbolRef::SF_Undefined;
     }
 
-    if (!(MachOType & MachO::N_PEXT))
+    if (MachOType & MachO::N_PEXT)
+      Result |= SymbolRef::SF_Hidden;
+    else
       Result |= SymbolRef::SF_Exported;
-  }
+
+  } else if (MachOType & MachO::N_PEXT)
+    Result |= SymbolRef::SF_Hidden;
 
   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
     Result |= SymbolRef::SF_Weak;