MC/Mach-O/x86_64: Add a new hook for checking whether a particular section can

be diced into atoms, and adjust getAtom() to take this into account.
 - This fixes relocations to symbols in fixed size literal sections, for
   example.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103532 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 162 insertions, 66 deletions

diff --git a/include/llvm/Target/TargetAsmBackend.h b/include/llvm/Target/TargetAsmBackend.h
index f350ecc..b390ca5 100644
--- a/include/llvm/Target/TargetAsmBackend.h
+++ b/include/llvm/Target/TargetAsmBackend.h
@@ -90,6 +90,14 @@ public:
     return false;
   }
 
+  /// isSectionAtomizable - Check whether the given section can be split into
+  /// atoms.
+  ///
+  /// \see MCAssembler::isSymbolLinkerVisible().
+  virtual bool isSectionAtomizable(const MCSection &Section) const {
+    return true;
+  }
+
   /// isVirtualSection - Check whether the given section is "virtual", that is
   /// has no actual object file contents.
   virtual bool isVirtualSection(const MCSection &Section) const = 0;
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index 65e3571..8ec927e 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -297,6 +297,12 @@ const MCSymbolData *MCAssembler::getAtom(const MCAsmLayout &Layout,
   if (!SD->getFragment())
     return 0;
 
+  // Non-linker visible symbols in sections which can't be atomized have no
+  // defining atom.
+  if (!getBackend().isSectionAtomizable(
+        SD->getFragment()->getParent()->getSection()))
+    return 0;
+
   // Otherwise, return the atom for the containing fragment.
   return SD->getFragment()->getAtom();
 }
diff --git a/lib/Target/X86/X86AsmBackend.cpp b/lib/Target/X86/X86AsmBackend.cpp
index b72601a..8ee836e 100644
--- a/lib/Target/X86/X86AsmBackend.cpp
+++ b/lib/Target/X86/X86AsmBackend.cpp
@@ -259,6 +259,26 @@ public:
     const MCSectionMachO &SMO = static_cast<const MCSectionMachO&>(Section);
     return SMO.getType() == MCSectionMachO::S_CSTRING_LITERALS;
   }
+
+  virtual bool isSectionAtomizable(const MCSection &Section) const {
+    const MCSectionMachO &SMO = static_cast<const MCSectionMachO&>(Section);
+    // Fixed sized data sections are uniqued, they cannot be diced into atoms.
+    switch (SMO.getType()) {
+    default:
+      return true;
+
+    case MCSectionMachO::S_4BYTE_LITERALS:
+    case MCSectionMachO::S_8BYTE_LITERALS:
+    case MCSectionMachO::S_16BYTE_LITERALS:
+    case MCSectionMachO::S_LITERAL_POINTERS:
+    case MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS:
+    case MCSectionMachO::S_LAZY_SYMBOL_POINTERS:
+    case MCSectionMachO::S_MOD_INIT_FUNC_POINTERS:
+    case MCSectionMachO::S_MOD_TERM_FUNC_POINTERS:
+    case MCSectionMachO::S_INTERPOSING:
+      return false;
+    }
+  }
 };
 
 }
diff --git a/test/MC/MachO/darwin-x86_64-reloc.s b/test/MC/MachO/darwin-x86_64-reloc.s
index 20b593f..248c507 100644
--- a/test/MC/MachO/darwin-x86_64-reloc.s
+++ b/test/MC/MachO/darwin-x86_64-reloc.s
@@ -64,37 +64,56 @@ L4:
         .long 0
         .text
         movl L4(%rip), %eax
+
+        .section __TEXT,__literal8,8byte_literals
+	.quad 0
+L5:     
+	.quad 0
+f6:
+        .quad 0
+L6:
+        .quad 0
+        
+        .text
+	movl L5(%rip), %eax
+	movl f6(%rip), %eax
+	movl L6(%rip), %eax
         
+        .data
+        .quad L5
+        .quad f6
+	.quad L6
+
 // CHECK: ('cputype', 16777223)
 // CHECK: ('cpusubtype', 3)
 // CHECK: ('filetype', 1)
 // CHECK: ('num_load_commands', 1)
-// CHECK: ('load_commands_size', 416)
+// CHECK: ('load_commands_size', 496)
 // CHECK: ('flag', 0)
 // CHECK: ('reserved', 0)
 // CHECK: ('load_commands', [
 // CHECK:   # Load Command 0
 // CHECK:  (('command', 25)
-// CHECK:   ('size', 312)
+// CHECK:   ('size', 392)
 // 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', 229)
-// CHECK:   ('file_offset', 448)
-// CHECK:   ('file_size', 229)
+// CHECK:   ('vm_size', 303)
+// CHECK:   ('file_offset', 528)
+// CHECK:   ('file_size', 303)
 // CHECK:   ('maxprot', 7)
 // CHECK:   ('initprot', 7)
-// CHECK:   ('num_sections', 3)
+// CHECK:   ('num_sections', 4)
 // CHECK:   ('flags', 0)
 // CHECK:   ('sections', [
 // CHECK:     # Section 0
 // CHECK:    (('section_name', '__data\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
 // CHECK:     ('segment_name', '__DATA\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
 // CHECK:     ('address', 0)
-// CHECK:     ('size', 16)
-// CHECK:     ('offset', 448)
+// CHECK:     ('size', 40)
+// CHECK:     ('offset', 528)
 // CHECK:     ('alignment', 0)
-// CHECK:     ('reloc_offset', 680)
-// CHECK:     ('num_reloc', 2)
+// CHECK:     ('reloc_offset', 832)
+// CHECK:     ('num_reloc', 5)
 // CHECK:     ('flags', 0x0)
 // CHECK:     ('reserved1', 0)
 // CHECK:     ('reserved2', 0)
@@ -102,22 +121,31 @@ L4:
 // CHECK:    ),
 // CHECK:   ('_relocations', [
 // CHECK:     # Relocation 0
+// CHECK:     (('word-0', 0x20),
+// CHECK:      ('word-1', 0x6000004)),
+// CHECK:     # Relocation 1
+// CHECK:     (('word-0', 0x18),
+// CHECK:      ('word-1', 0xe000006)),
+// CHECK:     # Relocation 2
+// CHECK:     (('word-0', 0x10),
+// CHECK:      ('word-1', 0x6000004)),
+// CHECK:     # Relocation 3
 // CHECK:     (('word-0', 0x8),
 // CHECK:      ('word-1', 0x4d000000)),
-// CHECK:     # Relocation 1
+// CHECK:     # Relocation 4
 // CHECK:     (('word-0', 0x4),
-// CHECK:      ('word-1', 0x4d000007)),
+// CHECK:      ('word-1', 0x4d000008)),
 // CHECK:   ])
-// CHECK:   ('_section_data', '\x00\x00\x00\x00\x04\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:   ('_section_data', "\x00\x00\x00\x00\x04\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x17\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'\x01\x00\x00\x00\x00\x00\x00")
 // CHECK:     # Section 1
 // 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', 16)
-// CHECK:     ('size', 197)
-// CHECK:     ('offset', 464)
+// CHECK:     ('address', 40)
+// CHECK:     ('size', 215)
+// CHECK:     ('offset', 568)
 // CHECK:     ('alignment', 0)
-// CHECK:     ('reloc_offset', 696)
-// CHECK:     ('num_reloc', 28)
+// CHECK:     ('reloc_offset', 872)
+// CHECK:     ('num_reloc', 31)
 // CHECK:     ('flags', 0x80000400)
 // CHECK:     ('reserved1', 0)
 // CHECK:     ('reserved2', 0)
@@ -125,99 +153,108 @@ L4:
 // CHECK:    ),
 // CHECK:   ('_relocations', [
 // CHECK:     # Relocation 0
+// CHECK:     (('word-0', 0xd3),
+// CHECK:      ('word-1', 0x15000004)),
+// CHECK:     # Relocation 1
+// CHECK:     (('word-0', 0xcd),
+// CHECK:      ('word-1', 0x1d000006)),
+// CHECK:     # Relocation 2
+// CHECK:     (('word-0', 0xc7),
+// CHECK:      ('word-1', 0x15000004)),
+// CHECK:     # Relocation 3
 // CHECK:     (('word-0', 0xc1),
 // CHECK:      ('word-1', 0x15000001)),
-// CHECK:     # Relocation 1
+// CHECK:     # Relocation 4
 // CHECK:     (('word-0', 0xa5),
 // CHECK:      ('word-1', 0x5e000003)),
-// CHECK:     # Relocation 2
+// CHECK:     # Relocation 5
 // CHECK:     (('word-0', 0xa5),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 3
+// CHECK:     # Relocation 6
 // CHECK:     (('word-0', 0x9d),
 // CHECK:      ('word-1', 0x5e000003)),
-// CHECK:     # Relocation 4
+// CHECK:     # Relocation 7
 // CHECK:     (('word-0', 0x9d),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 5
+// CHECK:     # Relocation 8
 // CHECK:     (('word-0', 0x95),
 // CHECK:      ('word-1', 0xe000003)),
-// CHECK:     # Relocation 6
+// CHECK:     # Relocation 9
 // CHECK:     (('word-0', 0x8d),
 // CHECK:      ('word-1', 0xe000003)),
-// CHECK:     # Relocation 7
+// CHECK:     # Relocation 10
 // CHECK:     (('word-0', 0x79),
 // CHECK:      ('word-1', 0x8d000003)),
-// CHECK:     # Relocation 8
+// CHECK:     # Relocation 11
 // CHECK:     (('word-0', 0x71),
 // CHECK:      ('word-1', 0x7d000003)),
-// CHECK:     # Relocation 9
+// CHECK:     # Relocation 12
 // CHECK:     (('word-0', 0x69),
 // CHECK:      ('word-1', 0x6d000003)),
-// CHECK:     # Relocation 10
+// CHECK:     # Relocation 13
 // CHECK:     (('word-0', 0x63),
 // CHECK:      ('word-1', 0x1d000003)),
-// CHECK:     # Relocation 11
+// CHECK:     # Relocation 14
 // CHECK:     (('word-0', 0x5c),
 // CHECK:      ('word-1', 0x1d000003)),
-// CHECK:     # Relocation 12
+// CHECK:     # Relocation 15
 // CHECK:     (('word-0', 0x55),
 // CHECK:      ('word-1', 0x5c000002)),
-// CHECK:     # Relocation 13
+// CHECK:     # Relocation 16
 // CHECK:     (('word-0', 0x55),
 // CHECK:      ('word-1', 0xc000000)),
-// CHECK:     # Relocation 14
+// CHECK:     # Relocation 17
 // CHECK:     (('word-0', 0x4d),
 // CHECK:      ('word-1', 0x5e000002)),
-// CHECK:     # Relocation 15
+// CHECK:     # Relocation 18
 // CHECK:     (('word-0', 0x4d),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 16
+// CHECK:     # Relocation 19
 // CHECK:     (('word-0', 0x45),
 // CHECK:      ('word-1', 0x5e000002)),
-// CHECK:     # Relocation 17
+// CHECK:     # Relocation 20
 // CHECK:     (('word-0', 0x45),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 18
+// CHECK:     # Relocation 21
 // CHECK:     (('word-0', 0x3d),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 19
+// CHECK:     # Relocation 22
 // CHECK:     (('word-0', 0x35),
 // CHECK:      ('word-1', 0xe000000)),
-// CHECK:     # Relocation 20
+// CHECK:     # Relocation 23
 // CHECK:     (('word-0', 0x2d),
 // CHECK:      ('word-1', 0x8d000000)),
-// CHECK:     # Relocation 21
+// CHECK:     # Relocation 24
 // CHECK:     (('word-0', 0x26),
 // CHECK:      ('word-1', 0x6d000000)),
-// CHECK:     # Relocation 22
+// CHECK:     # Relocation 25
 // CHECK:     (('word-0', 0x20),
 // CHECK:      ('word-1', 0x1d000000)),
-// CHECK:     # Relocation 23
+// CHECK:     # Relocation 26
 // CHECK:     (('word-0', 0x1a),
 // CHECK:      ('word-1', 0x1d000000)),
-// CHECK:     # Relocation 24
+// CHECK:     # Relocation 27
 // CHECK:     (('word-0', 0x14),
 // CHECK:      ('word-1', 0x4d000000)),
-// CHECK:     # Relocation 25
+// CHECK:     # Relocation 28
 // CHECK:     (('word-0', 0xe),
 // CHECK:      ('word-1', 0x3d000000)),
-// CHECK:     # Relocation 26
+// CHECK:     # Relocation 29
 // CHECK:     (('word-0', 0x7),
 // CHECK:      ('word-1', 0x2d000000)),
-// CHECK:     # Relocation 27
+// CHECK:     # Relocation 30
 // CHECK:     (('word-0', 0x2),
 // CHECK:      ('word-1', 0x2d000000)),
 // CHECK:   ])
-// CHECK:   ('_section_data', '\xc3\xe8\x00\x00\x00\x00\xe8\x04\x00\x00\x00H\x8b\x05\x00\x00\x00\x00\xff5\x00\x00\x00\x00\x8b\x05\x00\x00\x00\x00\x8b\x05\x04\x00\x00\x00\xc6\x05\xff\xff\xff\xff\x12\xc7\x05\xfc\xff\xff\xffxV4\x12\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00H\x8d\x05,\x00\x00\x00H\x8d\x05\x14\x00\x00\x00\x83\x05\x13\x00\x00\x00\x06f\x81\x05\x12\x00\x00\x00\xf4\x01\x81\x05\x10\x00\x00\x00\xf4\x01\x00\x00\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90,\x00\x00\x00\x00\x00\x00\x00\x14\x00\x00\x00\x00\x00\x00\x00\xe4\xff\xff\xff\xff\xff\xff\xff\xd4\xff\xff\xff\xff\xff\xff\xff,\x00\x00\x00\x00\x00\x00\x00\x83\xc0\x00\x03\x04%\x03\x00\x00\x00\x8b\x057\xff\xff\xff')
+// CHECK:   ('_section_data', '\xc3\xe8\x00\x00\x00\x00\xe8\x04\x00\x00\x00H\x8b\x05\x00\x00\x00\x00\xff5\x00\x00\x00\x00\x8b\x05\x00\x00\x00\x00\x8b\x05\x04\x00\x00\x00\xc6\x05\xff\xff\xff\xff\x12\xc7\x05\xfc\xff\xff\xffxV4\x12\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00H\x8d\x05,\x00\x00\x00H\x8d\x05\x14\x00\x00\x00\x83\x05\x13\x00\x00\x00\x06f\x81\x05\x12\x00\x00\x00\xf4\x01\x81\x05\x10\x00\x00\x00\xf4\x01\x00\x00\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90,\x00\x00\x00\x00\x00\x00\x00\x14\x00\x00\x00\x00\x00\x00\x00\xe4\xff\xff\xff\xff\xff\xff\xff\xd4\xff\xff\xff\xff\xff\xff\xff,\x00\x00\x00\x00\x00\x00\x00\x83\xc0\x00\x03\x04%\x03\x00\x00\x00\x8b\x05\x1f\xff\xff\xff\x8b\x05$\x00\x00\x00\x8b\x05\x00\x00\x00\x00\x8b\x05(\x00\x00\x00')
 // CHECK:     # Section 2
 // CHECK:    (('section_name', '__debug_frame\x00\x00\x00')
 // CHECK:     ('segment_name', '__DWARF\x00\x00\x00\x00\x00\x00\x00\x00\x00')
-// CHECK:     ('address', 213)
+// CHECK:     ('address', 255)
 // CHECK:     ('size', 16)
-// CHECK:     ('offset', 661)
+// CHECK:     ('offset', 783)
 // CHECK:     ('alignment', 0)
-// CHECK:     ('reloc_offset', 920)
+// CHECK:     ('reloc_offset', 1120)
 // CHECK:     ('num_reloc', 2)
 // CHECK:     ('flags', 0x2000000)
 // CHECK:     ('reserved1', 0)
@@ -227,29 +264,46 @@ L4:
 // CHECK:   ('_relocations', [
 // CHECK:     # Relocation 0
 // CHECK:     (('word-0', 0x8),
-// CHECK:      ('word-1', 0xe000006)),
+// CHECK:      ('word-1', 0xe000007)),
 // CHECK:     # Relocation 1
 // CHECK:     (('word-0', 0x0),
 // CHECK:      ('word-1', 0x6000002)),
 // CHECK:   ])
-// CHECK:   ('_section_data', '\xbd\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:   ('_section_data', '\xd5\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:     # Section 3
+// CHECK:    (('section_name', '__literal8\x00\x00\x00\x00\x00\x00')
+// CHECK:     ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+// CHECK:     ('address', 271)
+// CHECK:     ('size', 32)
+// CHECK:     ('offset', 799)
+// CHECK:     ('alignment', 0)
+// CHECK:     ('reloc_offset', 0)
+// CHECK:     ('num_reloc', 0)
+// CHECK:     ('flags', 0x4)
+// CHECK:     ('reserved1', 0)
+// CHECK:     ('reserved2', 0)
+// CHECK:     ('reserved3', 0)
+// CHECK:    ),
+// CHECK:   ('_relocations', [
+// CHECK:   ])
+// CHECK:   ('_section_data', '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
 // CHECK:   ])
 // CHECK:  ),
 // CHECK:   # Load Command 1
 // CHECK:  (('command', 2)
 // CHECK:   ('size', 24)
-// CHECK:   ('symoff', 936)
-// CHECK:   ('nsyms', 8)
-// CHECK:   ('stroff', 1064)
-// CHECK:   ('strsize', 48)
-// CHECK:   ('_string_data', '\x00_foobar\x00_ext_foo\x00_foo\x00_baz\x00_bar\x00_prev\x00_f2\x00_f3\x00\x00')
+// CHECK:   ('symoff', 1136)
+// CHECK:   ('nsyms', 9)
+// CHECK:   ('stroff', 1280)
+// CHECK:   ('strsize', 52)
+// CHECK:   ('_string_data', '\x00_foobar\x00_ext_foo\x00_foo\x00_baz\x00_bar\x00_prev\x00_f2\x00_f3\x00f6\x00\x00\x00')
 // CHECK:   ('_symbols', [
 // CHECK:     # Symbol 0
 // CHECK:    (('n_strx', 18)
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 16)
+// CHECK:     ('n_value', 40)
 // CHECK:     ('_string', '_foo')
 // CHECK:    ),
 // CHECK:     # Symbol 1
@@ -257,7 +311,7 @@ L4:
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 17)
+// CHECK:     ('n_value', 41)
 // CHECK:     ('_string', '_baz')
 // CHECK:    ),
 // CHECK:     # Symbol 2
@@ -265,7 +319,7 @@ L4:
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 77)
+// CHECK:     ('n_value', 101)
 // CHECK:     ('_string', '_bar')
 // CHECK:    ),
 // CHECK:     # Symbol 3
@@ -273,7 +327,7 @@ L4:
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 145)
+// CHECK:     ('n_value', 169)
 // CHECK:     ('_string', '_prev')
 // CHECK:    ),
 // CHECK:     # Symbol 4
@@ -281,7 +335,7 @@ L4:
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 197)
+// CHECK:     ('n_value', 221)
 // CHECK:     ('_string', '_f2')
 // CHECK:    ),
 // CHECK:     # Symbol 5
@@ -289,10 +343,18 @@ L4:
 // CHECK:     ('n_type', 0xe)
 // CHECK:     ('n_sect', 2)
 // CHECK:     ('n_desc', 0)
-// CHECK:     ('n_value', 200)
+// CHECK:     ('n_value', 224)
 // CHECK:     ('_string', '_f3')
 // CHECK:    ),
 // CHECK:     # Symbol 6
+// CHECK:    (('n_strx', 47)
+// CHECK:     ('n_type', 0xe)
+// CHECK:     ('n_sect', 4)
+// CHECK:     ('n_desc', 0)
+// CHECK:     ('n_value', 287)
+// CHECK:     ('_string', 'f6')
+// CHECK:    ),
+// CHECK:     # Symbol 7
 // CHECK:    (('n_strx', 9)
 // CHECK:     ('n_type', 0x1)
 // CHECK:     ('n_sect', 0)
@@ -300,7 +362,7 @@ L4:
 // CHECK:     ('n_value', 0)
 // CHECK:     ('_string', '_ext_foo')
 // CHECK:    ),
-// CHECK:     # Symbol 7
+// CHECK:     # Symbol 8
 // CHECK:    (('n_strx', 1)
 // CHECK:     ('n_type', 0x1)
 // CHECK:     ('n_sect', 0)
@@ -314,10 +376,10 @@ L4:
 // CHECK:  (('command', 11)
 // CHECK:   ('size', 80)
 // CHECK:   ('ilocalsym', 0)
-// CHECK:   ('nlocalsym', 6)
-// CHECK:   ('iextdefsym', 6)
+// CHECK:   ('nlocalsym', 7)
+// CHECK:   ('iextdefsym', 7)
 // CHECK:   ('nextdefsym', 0)
-// CHECK:   ('iundefsym', 6)
+// CHECK:   ('iundefsym', 7)
 // CHECK:   ('nundefsym', 2)
 // CHECK:   ('tocoff', 0)
 // CHECK:   ('ntoc', 0)