Fix a Darwin x86_64 special case of a jmp to a temporary symbol from an atom

without a base symbol that must not have a relocation entry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139316 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 7011916770fbe3ea91b9910b1273a6be6fe55841..ef0a93d93b257f2f06baec62a3d8cd73abb4ef9d 100644 (file)
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -590,6 +590,16 @@ IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
         return false;
       return true;
     }
+    // For Darwin x86_64, there is one special case when the reference IsPCRel.
+    // If the fragment with the reference does not have a base symbol but meets
+    // the simple way of dealing with this, in that it is a temporary symbol in
+    // the same atom then it is assumed to be fully resolved.  This is needed so
+    // a relocation entry is not created and so the staitic linker does not
+    // mess up the reference later.
+    else if(!FB.getAtom() &&
+            SA.isTemporary() && SA.isInSection() && &SecA == &SecB){
+      return true;
+    }
   } else {
     if (!TargetObjectWriter->useAggressiveSymbolFolding())
       return false;

diff --git a/test/MC/MachO/darwin-x86_64-nobase-relocs.s b/test/MC/MachO/darwin-x86_64-nobase-relocs.s
new file mode 100644 (file)
index 0000000..a90b3e4
--- /dev/null
+++ b/test/MC/MachO/darwin-x86_64-nobase-relocs.s
@@ -0,0 +1,58 @@
+// RUN: llvm-mc -n -triple x86_64-apple-darwin9 %s -filetype=obj -o - | macho-dump --dump-section-data | FileCheck %s
+
+// Test case for rdar://10062261
+
+// Must be no base, non-temporary, symbol before the reference to Lbar at the
+// start of the section.  What we are testing for is that the reference does not
+// create a relocation entry.
+.text
+Ladd:
+       nop
+       jmp Lbar
+       .byte 0x0f,0x1f,0x40,0x00
+       .byte 0x0f,0x1f,0x40,0x00
+Lbar:  
+       mov $1, %eax
+       ret
+
+// CHECK: ('cputype', 16777223)
+// CHECK: ('cpusubtype', 3)
+// CHECK: ('filetype', 1)
+// CHECK: ('num_load_commands', 1)
+// CHECK: ('load_commands_size', 152)
+// CHECK: ('flag', 0)
+// CHECK: ('reserved', 0)
+// CHECK: ('load_commands', [
+// CHECK:   # Load Command 0
+// CHECK:  (('command', 25)
+// CHECK:   ('size', 152)
+// CHECK:   ('segment_name', '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:   ('vm_addr', 0)
+// CHECK:   ('vm_size', 17)
+// CHECK:   ('file_offset', 184)
+// CHECK:   ('file_size', 17)
+// CHECK:   ('maxprot', 7)
+// CHECK:   ('initprot', 7)
+// CHECK:   ('num_sections', 1)
+// CHECK:   ('flags', 0)
+// CHECK:   ('sections', [
+// CHECK:     # Section 0
+// CHECK:    (('section_name', '__text\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:     ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:     ('address', 0)
+// CHECK:     ('size', 17)
+// CHECK:     ('offset', 184)
+// CHECK:     ('alignment', 0)
+// CHECK:     ('reloc_offset', 0)
+// CHECK:     ('num_reloc', 0)
+// CHECK:     ('flags', 0x80000400)
+// CHECK:     ('reserved1', 0)
+// CHECK:     ('reserved2', 0)
+// CHECK:     ('reserved3', 0)
+// CHECK:    ),
+// CHECK:   ('_relocations', [
+// CHECK:   ])
+// CHECK:   ('_section_data', '90eb080f 1f40000f 1f4000b8 01000000 c3')
+// CHECK:   ])
+// CHECK:  ),
+// CHECK: ])