[MC] Sort DWARF FDEs by the associated CIE before emitting them.

[efriedma]

Summary

This isn't technically necessary according to the DWARF standard, but the Android libunwindstack rejects eh_frame sections where an FDE refers to a CIE other than the closest previous CIE.

I think I would consider this a bug in libunwindstack... as far as I can tell, the DWARF standard doesn't contain any requirement like this. And
I'm not sure we should be adding workarounds for specific unwind implementations. But I have the patch anyway, so I'm posting it.

I'd appreciate it if someone from Google could contact the owners of libstackunwind to see if they have any opinion on this.

[srhines]

I asked Chris to comment here about libunwindstack. Hopefully we can get the problem fixed, but I think this workaround might be necessary for code running on older devices in any case (i.e. NDK apps).

[compnerd]

Actually, I'm not sure if that is a bug in libstackunwind, but rather in LLVM. I think that this is the behaviour that GCC has specifically for the eh_frame section. This constraint is not part of the DWARF spec, but eh_frame even though it is similar to debug_frame, is not part of the DWARF spec, it just uses a similar encoding. The change itself looks good, but, please wait for the discussion to complete before committing this.

lib/MC/MCDwarf.cpp

1857 ↗

(On Diff #186943)

While you are in the area, mind just switching this over to a range-based for loop?

[JohnReagan]

I asked my local expert for an opinion.

"The comments about the DWARF standard are correct. I don’t think it imposes any order or restriction on the placement of FDE’s and CIE’s.

However, the Linux Standard Base design is such that FDE’s can only refer to prior CIE’s, not ones that appear later in .eh_frame. This restriction arises because the CIE pointer in FDE’s are self-relative offsets, and the offset is an unsigned quantity which is always subtracted from the FDE location.

Seems to me that, given this, there’s only two ways you’d want to organize FDE’s and CIE’s: either bunch all the CIE’s at the beginning, followed by all the FDE’s; or each CIE is followed by all its FDE’s. This proposal is suggesting eliminating the former as an option. I wasn’t there when the LSB was formalized, but it seems to me that if they had wanted to have each CIE followed by all its FDE’s, they wouldn’t have put a pointer to the CIE in the FDE in the first place. Would have saved some space and complexity."

[efriedma]

Any other comments on this?

[efriedma]

lib/MC/MCDwarf.cpp

1857 ↗

(On Diff #186943)

I looked at it briefly, but the iterators are used inside the loop to check whether the current CFE is the last one, so there isn't any easy way to express this as a range-based loop.

[lhames]

Late to the party here, but if the DWARF spec doesn’t require FDEs to refer to the most recent CIE, is it worth making this optional, even if it’s on by default? Otherwise we risk writing code that assumes this sanitized layout when the spec doesn’t guarantee it.

I actually just hit this issue in JITLink: its eh-frame parser used to assume that FDEs referred to the most recent CIE (because of course they would, right?), but then broke on output from older clangs. I relaxed JITLink’s eh-frame parser to support references to any previous CIE, only to discover that I could no longer write a test case now that LLVM unconditionally does the “right” thing. :P

[lhames]

Actually never mind: The right thing to do is add the test with a checked in binary (or yaml2obj test case, if I can make that work).

llvm/trunk/lib/MC/MCDwarf.cpp

struct CIEKey {
 
   explicit CIEKey(const MCDwarfFrameInfo &Frame)
       : Personality(Frame.Personality),
         PersonalityEncoding(Frame.PersonalityEncoding),
         LsdaEncoding(Frame.LsdaEncoding), IsSignalFrame(Frame.IsSignalFrame),
         IsSimple(Frame.IsSimple), RAReg(Frame.RAReg),
         IsBKeyFrame(Frame.IsBKeyFrame) {}
 
+  StringRef PersonalityName() const {
+    if (!Personality)
+      return StringRef();
+    return Personality->getName();
+  }
+
+  bool operator<(const CIEKey &Other) const {
+    return std::make_tuple(PersonalityName(), PersonalityEncoding, LsdaEncoding,
+                           IsSignalFrame, IsSimple, RAReg) <
+           std::make_tuple(Other.PersonalityName(), Other.PersonalityEncoding,
+                           Other.LsdaEncoding, Other.IsSignalFrame,
+                           Other.IsSimple, Other.RAReg);
+  }
+
   const MCSymbol *Personality;
   unsigned PersonalityEncoding;
   unsigned LsdaEncoding;
   bool IsSignalFrame;
   bool IsSimple;
   unsigned RAReg;
   bool IsBKeyFrame;
 };
void MCDwarfFrameEmitter::Emit(MCObjectStreamer &Streamer, MCAsmBackend *MAB,
   Streamer.SwitchSection(&Section);
   MCSymbol *SectionStart = Context.createTempSymbol();
   Streamer.EmitLabel(SectionStart);
 
   DenseMap<CIEKey, const MCSymbol *> CIEStarts;
 
   const MCSymbol *DummyDebugKey = nullptr;
   bool CanOmitDwarf = MOFI->getOmitDwarfIfHaveCompactUnwind();
-  for (auto I = FrameArray.begin(), E = FrameArray.end(); I != E;) {
+  // Sort the FDEs by their corresponding CIE before we emit them.
+  // This isn't technically necessary according to the DWARF standard,
+  // but the Android libunwindstack rejects eh_frame sections where
+  // an FDE refers to a CIE other than the closest previous CIE.
+  std::vector<MCDwarfFrameInfo> FrameArrayX(FrameArray.begin(), FrameArray.end());
+  std::stable_sort(
+      FrameArrayX.begin(), FrameArrayX.end(),
+      [&](const MCDwarfFrameInfo &X, const MCDwarfFrameInfo &Y) -> bool {
+        return CIEKey(X) < CIEKey(Y);
+      });
+  for (auto I = FrameArrayX.begin(), E = FrameArrayX.end(); I != E;) {
     const MCDwarfFrameInfo &Frame = *I;
     ++I;
     if (CanOmitDwarf && Frame.CompactUnwindEncoding !=
           MOFI->getCompactUnwindDwarfEHFrameOnly())
       // Don't generate an EH frame if we don't need one. I.e., it's taken care
       // of by the compact unwind encoding.
       continue;
 

llvm/trunk/test/CodeGen/AArch64/arm64-big-endian-eh.ll

define linkonce_odr hidden void @__clang_call_terminate(i8*) #1 {
   %2 = tail call i8* @__cxa_begin_catch(i8* %0) #2
   tail call void @_ZSt9terminatev() #3
   unreachable
 }
 
 declare void @_ZSt9terminatev()
 
 ; CHECK-LABEL: Contents of section .eh_frame:
+; CHECK-NEXT: {{^ 0000}}
+; CHECK-NEXT: {{^ 0010}}
 ; CHECK-NEXT: 0000 0000001c
 

llvm/trunk/test/MC/ELF/cfi-signal-frame.s

 // CHECK-NEXT:     Address: 0x0
 // CHECK-NEXT:     Offset: 0x40
 // CHECK-NEXT:     Size: 88
 // CHECK-NEXT:     Link: 0
 // CHECK-NEXT:     Info: 0
 // CHECK-NEXT:     AddressAlignment: 8
 // CHECK-NEXT:     EntrySize: 0
 // CHECK-NEXT:     SectionData (
-// CHECK-NEXT:       0000: 14000000 00000000 017A5253 00017810
-// CHECK-NEXT:       0010: 011B0C07 08900100 10000000 1C000000
-// CHECK-NEXT:       0020: 00000000 00000000 00000000 14000000
-// CHECK-NEXT:       0030: 00000000 017A5200 01781001 1B0C0708
-// CHECK-NEXT:       0040: 90010000 10000000 1C000000 00000000
-// CHECK-NEXT:       0050: 00000000 00000000
+// CHECK-NEXT:       0000: 14000000 00000000 017A5200 01781001  |.........zR..x..|
+// CHECK-NEXT:       0010: 1B0C0708 90010000 10000000 1C000000  |................|
+// CHECK-NEXT:       0020: 00000000 00000000 00000000 14000000  |................|
+// CHECK-NEXT:       0030: 00000000 017A5253 00017810 011B0C07  |.....zRS..x.....|
+// CHECK-NEXT:       0040: 08900100 10000000 1C000000 00000000  |................|
+// CHECK-NEXT:       0050: 00000000 00000000                    |........|
 // CHECK-NEXT:     )
 // CHECK-NEXT:   }

llvm/trunk/test/MC/ELF/cfi.s

 // CHECK-NEXT:     Size: 1776
 // CHECK-NEXT:     Link: 0
 // CHECK-NEXT:     Info: 0
 // CHECK-NEXT:     AddressAlignment: 8
 // CHECK-NEXT:     EntrySize: 0
 // CHECK-NEXT:     Relocations [
 // CHECK-NEXT:     ]
 // CHECK-NEXT:     SectionData (
-// CHECK-NEXT:       0000: 14000000 00000000 017A4C52 00017810
-// CHECK-NEXT:       0010: 02031B0C 07089001 14000000 1C000000
-// CHECK-NEXT:       0020: 00000000 01000000 04000000 00000000
-// CHECK-NEXT:       0030: 20000000 00000000 017A504C 52000178
-// CHECK-NEXT:       0040: 100B0000 00000000 00000003 1B0C0708
-// CHECK-NEXT:       0050: 90010000 14000000 28000000 00000000
-// CHECK-NEXT:       0060: 01000000 04000000 00000000 14000000
-// CHECK-NEXT:       0070: 70000000 00000000 01000000 04000000
-// CHECK-NEXT:       0080: 00000000 20000000 00000000 017A504C
-// CHECK-NEXT:       0090: 52000178 100B0000 00000000 00000002
-// CHECK-NEXT:       00A0: 1B0C0708 90010000 10000000 28000000
-// CHECK-NEXT:       00B0: 00000000 01000000 02000000 18000000
-// CHECK-NEXT:       00C0: 00000000 017A5052 00017810 04020000
-// CHECK-NEXT:       00D0: 1B0C0708 90010000 10000000 20000000
-// CHECK-NEXT:       00E0: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       00F0: 00000000 017A5052 00017810 06030000
-// CHECK-NEXT:       0100: 00001B0C 07089001 10000000 20000000
-// CHECK-NEXT:       0110: 00000000 01000000 00000000 1C000000
-// CHECK-NEXT:       0120: 00000000 017A5052 00017810 0A040000
-// CHECK-NEXT:       0130: 00000000 00001B0C 07089001 10000000
-// CHECK-NEXT:       0140: 24000000 00000000 01000000 00000000
-// CHECK-NEXT:       0150: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0160: 040A0000 1B0C0708 90010000 10000000
-// CHECK-NEXT:       0170: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       0180: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0190: 060B0000 00001B0C 07089001 10000000
-// CHECK-NEXT:       01A0: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       01B0: 1C000000 00000000 017A5052 00017810
-// CHECK-NEXT:       01C0: 0A0C0000 00000000 00001B0C 07089001
-// CHECK-NEXT:       01D0: 10000000 24000000 00000000 01000000
-// CHECK-NEXT:       01E0: 00000000 1C000000 00000000 017A5052
-// CHECK-NEXT:       01F0: 00017810 0A080000 00000000 00001B0C
-// CHECK-NEXT:       0200: 07089001 10000000 24000000 00000000
-// CHECK-NEXT:       0210: 01000000 00000000 1C000000 00000000
-// CHECK-NEXT:       0220: 017A5052 00017810 0A100000 00000000
-// CHECK-NEXT:       0230: 00001B0C 07089001 10000000 24000000
-// CHECK-NEXT:       0240: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       0250: 00000000 017A5052 00017810 04120000
-// CHECK-NEXT:       0260: 1B0C0708 90010000 10000000 20000000
-// CHECK-NEXT:       0270: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       0280: 00000000 017A5052 00017810 06130000
-// CHECK-NEXT:       0290: 00001B0C 07089001 10000000 20000000
-// CHECK-NEXT:       02A0: 00000000 01000000 00000000 1C000000
-// CHECK-NEXT:       02B0: 00000000 017A5052 00017810 0A140000
-// CHECK-NEXT:       02C0: 00000000 00001B0C 07089001 10000000
-// CHECK-NEXT:       02D0: 24000000 00000000 01000000 00000000
-// CHECK-NEXT:       02E0: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       02F0: 041A0000 1B0C0708 90010000 10000000
-// CHECK-NEXT:       0300: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       0310: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0320: 061B0000 00001B0C 07089001 10000000
-// CHECK-NEXT:       0330: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       0340: 1C000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0350: 0A1C0000 00000000 00001B0C 07089001
-// CHECK-NEXT:       0360: 10000000 24000000 00000000 01000000
-// CHECK-NEXT:       0370: 00000000 1C000000 00000000 017A5052
-// CHECK-NEXT:       0380: 00017810 0A180000 00000000 00001B0C
-// CHECK-NEXT:       0390: 07089001 10000000 24000000 00000000
-// CHECK-NEXT:       03A0: 01000000 00000000 1C000000 00000000
-// CHECK-NEXT:       03B0: 017A5052 00017810 0A800000 00000000
-// CHECK-NEXT:       03C0: 00001B0C 07089001 10000000 24000000
-// CHECK-NEXT:       03D0: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       03E0: 00000000 017A5052 00017810 04820000
-// CHECK-NEXT:       03F0: 1B0C0708 90010000 10000000 20000000
-// CHECK-NEXT:       0400: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       0410: 00000000 017A5052 00017810 06830000
-// CHECK-NEXT:       0420: 00001B0C 07089001 10000000 20000000
-// CHECK-NEXT:       0430: 00000000 01000000 00000000 1C000000
-// CHECK-NEXT:       0440: 00000000 017A5052 00017810 0A840000
-// CHECK-NEXT:       0450: 00000000 00001B0C 07089001 10000000
-// CHECK-NEXT:       0460: 24000000 00000000 01000000 00000000
-// CHECK-NEXT:       0470: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0480: 048A0000 1B0C0708 90010000 10000000
-// CHECK-NEXT:       0490: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       04A0: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       04B0: 068B0000 00001B0C 07089001 10000000
-// CHECK-NEXT:       04C0: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       04D0: 1C000000 00000000 017A5052 00017810
-// CHECK-NEXT:       04E0: 0A8C0000 00000000 00001B0C 07089001
-// CHECK-NEXT:       04F0: 10000000 24000000 00000000 01000000
-// CHECK-NEXT:       0500: 00000000 1C000000 00000000 017A5052
-// CHECK-NEXT:       0510: 00017810 0A880000 00000000 00001B0C
-// CHECK-NEXT:       0520: 07089001 10000000 24000000 00000000
-// CHECK-NEXT:       0530: 01000000 00000000 1C000000 00000000
-// CHECK-NEXT:       0540: 017A5052 00017810 0A900000 00000000
-// CHECK-NEXT:       0550: 00001B0C 07089001 10000000 24000000
-// CHECK-NEXT:       0560: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       0570: 00000000 017A5052 00017810 04920000
-// CHECK-NEXT:       0580: 1B0C0708 90010000 10000000 20000000
-// CHECK-NEXT:       0590: 00000000 01000000 00000000 18000000
-// CHECK-NEXT:       05A0: 00000000 017A5052 00017810 06930000
-// CHECK-NEXT:       05B0: 00001B0C 07089001 10000000 20000000
-// CHECK-NEXT:       05C0: 00000000 01000000 00000000 1C000000
-// CHECK-NEXT:       05D0: 00000000 017A5052 00017810 0A940000
-// CHECK-NEXT:       05E0: 00000000 00001B0C 07089001 10000000
-// CHECK-NEXT:       05F0: 24000000 00000000 01000000 00000000
-// CHECK-NEXT:       0600: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0610: 049A0000 1B0C0708 90010000 10000000
-// CHECK-NEXT:       0620: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       0630: 18000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0640: 069B0000 00001B0C 07089001 10000000
-// CHECK-NEXT:       0650: 20000000 00000000 01000000 00000000
-// CHECK-NEXT:       0660: 1C000000 00000000 017A5052 00017810
-// CHECK-NEXT:       0670: 0A9C0000 00000000 00001B0C 07089001
-// CHECK-NEXT:       0680: 10000000 24000000 00000000 01000000
-// CHECK-NEXT:       0690: 00000000 1C000000 00000000 017A5052
-// CHECK-NEXT:       06A0: 00017810 0A980000 00000000 00001B0C
-// CHECK-NEXT:       06B0: 07089001 10000000 24000000 00000000
-// CHECK-NEXT:       06C0: 01000000 00000000 10000000 00000000
-// CHECK-NEXT:       06D0: 017A5200 01781001 1B000000 10000000
-// CHECK-NEXT:       06E0: 18000000 00000000 01000000 00000000
-// CHECK-NEXT:     )
-// CHECK-NEXT:   }
+// CHECK-NEXT:       0000: 10000000 00000000 017A5200 01781001  |.........zR..x..|
+// CHECK-NEXT:       0010: 1B000000 10000000 18000000 00000000  |................|
+// CHECK-NEXT:       0020: 01000000 00000000 14000000 00000000  |................|
+// CHECK-NEXT:       0030: 017A4C52 00017810 02031B0C 07089001  |.zLR..x.........|
+// CHECK-NEXT:       0040: 14000000 1C000000 00000000 01000000  |................|
+// CHECK-NEXT:       0050: 04000000 00000000 14000000 34000000  |............4...|
+// CHECK-NEXT:       0060: 00000000 01000000 04000000 00000000  |................|
+// CHECK-NEXT:       0070: 20000000 00000000 017A504C 52000178  | ........zPLR..x|
+// CHECK-NEXT:       0080: 100B0000 00000000 00000002 1B0C0708  |................|
+// CHECK-NEXT:       0090: 90010000 10000000 28000000 00000000  |........(.......|
+// CHECK-NEXT:       00A0: 01000000 02000000 20000000 00000000  |........ .......|
+// CHECK-NEXT:       00B0: 017A504C 52000178 100B0000 00000000  |.zPLR..x........|
+// CHECK-NEXT:       00C0: 00000003 1B0C0708 90010000 14000000  |................|
+// CHECK-NEXT:       00D0: 28000000 00000000 01000000 04000000  |(...............|
+// CHECK-NEXT:       00E0: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       00F0: 00017810 04020000 1B0C0708 90010000  |..x.............|
+// CHECK-NEXT:       0100: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       0110: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0120: 00017810 06030000 00001B0C 07089001  |..x.............|
+// CHECK-NEXT:       0130: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       0140: 00000000 1C000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0150: 00017810 0A040000 00000000 00001B0C  |..x.............|
+// CHECK-NEXT:       0160: 07089001 10000000 24000000 00000000  |........$.......|
+// CHECK-NEXT:       0170: 01000000 00000000 1C000000 00000000  |................|
+// CHECK-NEXT:       0180: 017A5052 00017810 0A080000 00000000  |.zPR..x.........|
+// CHECK-NEXT:       0190: 00001B0C 07089001 10000000 24000000  |............$...|
+// CHECK-NEXT:       01A0: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       01B0: 00000000 017A5052 00017810 040A0000  |.....zPR..x.....|
+// CHECK-NEXT:       01C0: 1B0C0708 90010000 10000000 20000000  |............ ...|
+// CHECK-NEXT:       01D0: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       01E0: 00000000 017A5052 00017810 060B0000  |.....zPR..x.....|
+// CHECK-NEXT:       01F0: 00001B0C 07089001 10000000 20000000  |............ ...|
+// CHECK-NEXT:       0200: 00000000 01000000 00000000 1C000000  |................|
+// CHECK-NEXT:       0210: 00000000 017A5052 00017810 0A0C0000  |.....zPR..x.....|
+// CHECK-NEXT:       0220: 00000000 00001B0C 07089001 10000000  |................|
+// CHECK-NEXT:       0230: 24000000 00000000 01000000 00000000  |$...............|
+// CHECK-NEXT:       0240: 1C000000 00000000 017A5052 00017810  |.........zPR..x.|
+// CHECK-NEXT:       0250: 0A100000 00000000 00001B0C 07089001  |................|
+// CHECK-NEXT:       0260: 10000000 24000000 00000000 01000000  |....$...........|
+// CHECK-NEXT:       0270: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0280: 00017810 04120000 1B0C0708 90010000  |..x.............|
+// CHECK-NEXT:       0290: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       02A0: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       02B0: 00017810 06130000 00001B0C 07089001  |..x.............|
+// CHECK-NEXT:       02C0: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       02D0: 00000000 1C000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       02E0: 00017810 0A140000 00000000 00001B0C  |..x.............|
+// CHECK-NEXT:       02F0: 07089001 10000000 24000000 00000000  |........$.......|
+// CHECK-NEXT:       0300: 01000000 00000000 1C000000 00000000  |................|
+// CHECK-NEXT:       0310: 017A5052 00017810 0A180000 00000000  |.zPR..x.........|
+// CHECK-NEXT:       0320: 00001B0C 07089001 10000000 24000000  |............$...|
+// CHECK-NEXT:       0330: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       0340: 00000000 017A5052 00017810 041A0000  |.....zPR..x.....|
+// CHECK-NEXT:       0350: 1B0C0708 90010000 10000000 20000000  |............ ...|
+// CHECK-NEXT:       0360: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       0370: 00000000 017A5052 00017810 061B0000  |.....zPR..x.....|
+// CHECK-NEXT:       0380: 00001B0C 07089001 10000000 20000000  |............ ...|
+// CHECK-NEXT:       0390: 00000000 01000000 00000000 1C000000  |................|
+// CHECK-NEXT:       03A0: 00000000 017A5052 00017810 0A1C0000  |.....zPR..x.....|
+// CHECK-NEXT:       03B0: 00000000 00001B0C 07089001 10000000  |................|
+// CHECK-NEXT:       03C0: 24000000 00000000 01000000 00000000  |$...............|
+// CHECK-NEXT:       03D0: 1C000000 00000000 017A5052 00017810  |.........zPR..x.|
+// CHECK-NEXT:       03E0: 0A800000 00000000 00001B0C 07089001  |................|
+// CHECK-NEXT:       03F0: 10000000 24000000 00000000 01000000  |....$...........|
+// CHECK-NEXT:       0400: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0410: 00017810 04820000 1B0C0708 90010000  |..x.............|
+// CHECK-NEXT:       0420: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       0430: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0440: 00017810 06830000 00001B0C 07089001  |..x.............|
+// CHECK-NEXT:       0450: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       0460: 00000000 1C000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0470: 00017810 0A840000 00000000 00001B0C  |..x.............|
+// CHECK-NEXT:       0480: 07089001 10000000 24000000 00000000  |........$.......|
+// CHECK-NEXT:       0490: 01000000 00000000 1C000000 00000000  |................|
+// CHECK-NEXT:       04A0: 017A5052 00017810 0A880000 00000000  |.zPR..x.........|
+// CHECK-NEXT:       04B0: 00001B0C 07089001 10000000 24000000  |............$...|
+// CHECK-NEXT:       04C0: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       04D0: 00000000 017A5052 00017810 048A0000  |.....zPR..x.....|
+// CHECK-NEXT:       04E0: 1B0C0708 90010000 10000000 20000000  |............ ...|
+// CHECK-NEXT:       04F0: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       0500: 00000000 017A5052 00017810 068B0000  |.....zPR..x.....|
+// CHECK-NEXT:       0510: 00001B0C 07089001 10000000 20000000  |............ ...|
+// CHECK-NEXT:       0520: 00000000 01000000 00000000 1C000000  |................|
+// CHECK-NEXT:       0530: 00000000 017A5052 00017810 0A8C0000  |.....zPR..x.....|
+// CHECK-NEXT:       0540: 00000000 00001B0C 07089001 10000000  |................|
+// CHECK-NEXT:       0550: 24000000 00000000 01000000 00000000  |$...............|
+// CHECK-NEXT:       0560: 1C000000 00000000 017A5052 00017810  |.........zPR..x.|
+// CHECK-NEXT:       0570: 0A900000 00000000 00001B0C 07089001  |................|
+// CHECK-NEXT:       0580: 10000000 24000000 00000000 01000000  |....$...........|
+// CHECK-NEXT:       0590: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       05A0: 00017810 04920000 1B0C0708 90010000  |..x.............|
+// CHECK-NEXT:       05B0: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       05C0: 00000000 18000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       05D0: 00017810 06930000 00001B0C 07089001  |..x.............|
+// CHECK-NEXT:       05E0: 10000000 20000000 00000000 01000000  |.... ...........|
+// CHECK-NEXT:       05F0: 00000000 1C000000 00000000 017A5052  |.............zPR|
+// CHECK-NEXT:       0600: 00017810 0A940000 00000000 00001B0C  |..x.............|
+// CHECK-NEXT:       0610: 07089001 10000000 24000000 00000000  |........$.......|
+// CHECK-NEXT:       0620: 01000000 00000000 1C000000 00000000  |................|
+// CHECK-NEXT:       0630: 017A5052 00017810 0A980000 00000000  |.zPR..x.........|
+// CHECK-NEXT:       0640: 00001B0C 07089001 10000000 24000000  |............$...|
+// CHECK-NEXT:       0650: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       0660: 00000000 017A5052 00017810 049A0000  |.....zPR..x.....|
+// CHECK-NEXT:       0670: 1B0C0708 90010000 10000000 20000000  |............ ...|
+// CHECK-NEXT:       0680: 00000000 01000000 00000000 18000000  |................|
+// CHECK-NEXT:       0690: 00000000 017A5052 00017810 069B0000  |.....zPR..x.....|
+// CHECK-NEXT:       06A0: 00001B0C 07089001 10000000 20000000  |............ ...|
+// CHECK-NEXT:       06B0: 00000000 01000000 00000000 1C000000  |................|
+// CHECK-NEXT:       06C0: 00000000 017A5052 00017810 0A9C0000  |.....zPR..x.....|
+// CHECK-NEXT:       06D0: 00000000 00001B0C 07089001 10000000  |................|
+// CHECK-NEXT:       06E0: 24000000 00000000 01000000 00000000  |$...............|
 
 // CHECK:        Section {
 // CHECK:          Index:
 // CHECK:          Name: .rela.eh_frame
 // CHECK-NEXT:     Type: SHT_RELA
 // CHECK-NEXT:     Flags [
 // CHECK-NEXT:     ]
 // CHECK-NEXT:     Address: 0x0
 // CHECK-NEXT:     Offset:
 // CHECK-NEXT:     Size: 1752
 // CHECK-NEXT:     Link:
 // CHECK-NEXT:     Info:
 // CHECK-NEXT:     AddressAlignment: 8
 // CHECK-NEXT:     EntrySize: 24
 // CHECK-NEXT:     Relocations [
-// CHECK-NEXT:       0x20  R_X86_64_PC32 .text 0x0
-// CHECK-NEXT:       0x29  R_X86_64_32   bar   0x0
-// CHECK-NEXT:       0x43  R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x5C  R_X86_64_PC32 .text 0x1
-// CHECK-NEXT:       0x65  R_X86_64_32   bar   0x0
-// CHECK-NEXT:       0x74  R_X86_64_PC32 .text 0x2
-// CHECK-NEXT:       0x7D  R_X86_64_32   bar   0x0
-// CHECK-NEXT:       0x97  R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0xB0  R_X86_64_PC32 .text 0x3
-// CHECK-NEXT:       0xB9  R_X86_64_16   bar   0x0
-// CHECK-NEXT:       0xCE  R_X86_64_16   foo   0x0
-// CHECK-NEXT:       0xE0  R_X86_64_PC32 .text 0x4
-// CHECK-NEXT:       0xFE  R_X86_64_32   foo   0x0
-// CHECK-NEXT:       0x110 R_X86_64_PC32 .text 0x5
-// CHECK-NEXT:       0x12E R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x144 R_X86_64_PC32 .text 0x6
-// CHECK-NEXT:       0x162 R_X86_64_16   foo   0x0
-// CHECK-NEXT:       0x174 R_X86_64_PC32 .text 0x7
-// CHECK-NEXT:       0x192 R_X86_64_32   foo   0x0
-// CHECK-NEXT:       0x1A4 R_X86_64_PC32 .text 0x8
-// CHECK-NEXT:       0x1C2 R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x1D8 R_X86_64_PC32 .text 0x9
-// CHECK-NEXT:       0x1F6 R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x20C R_X86_64_PC32 .text 0xA
-// CHECK-NEXT:       0x22A R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x240 R_X86_64_PC32 .text 0xB
-// CHECK-NEXT:       0x25E R_X86_64_PC16 foo   0x0
-// CHECK-NEXT:       0x270 R_X86_64_PC32 .text 0xC
-// CHECK-NEXT:       0x28E R_X86_64_PC32 foo   0x0
-// CHECK-NEXT:       0x2A0 R_X86_64_PC32 .text 0xD
-// CHECK-NEXT:       0x2BE R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x2D4 R_X86_64_PC32 .text 0xE
-// CHECK-NEXT:       0x2F2 R_X86_64_PC16 foo   0x0
-// CHECK-NEXT:       0x304 R_X86_64_PC32 .text 0xF
-// CHECK-NEXT:       0x322 R_X86_64_PC32 foo   0x0
-// CHECK-NEXT:       0x334 R_X86_64_PC32 .text 0x10
-// CHECK-NEXT:       0x352 R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x368 R_X86_64_PC32 .text 0x11
-// CHECK-NEXT:       0x386 R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x39C R_X86_64_PC32 .text 0x12
-// CHECK-NEXT:       0x3BA R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x3D0 R_X86_64_PC32 .text 0x13
-// CHECK-NEXT:       0x3EE R_X86_64_16   foo   0x0
-// CHECK-NEXT:       0x400 R_X86_64_PC32 .text 0x14
-// CHECK-NEXT:       0x41E R_X86_64_32   foo   0x0
-// CHECK-NEXT:       0x430 R_X86_64_PC32 .text 0x15
-// CHECK-NEXT:       0x44E R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x464 R_X86_64_PC32 .text 0x16
-// CHECK-NEXT:       0x482 R_X86_64_16   foo   0x0
-// CHECK-NEXT:       0x494 R_X86_64_PC32 .text 0x17
-// CHECK-NEXT:       0x4B2 R_X86_64_32   foo   0x0
-// CHECK-NEXT:       0x4C4 R_X86_64_PC32 .text 0x18
-// CHECK-NEXT:       0x4E2 R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x4F8 R_X86_64_PC32 .text 0x19
-// CHECK-NEXT:       0x516 R_X86_64_64   foo   0x0
-// CHECK-NEXT:       0x52C R_X86_64_PC32 .text 0x1A
-// CHECK-NEXT:       0x54A R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x560 R_X86_64_PC32 .text 0x1B
-// CHECK-NEXT:       0x57E R_X86_64_PC16 foo   0x0
-// CHECK-NEXT:       0x590 R_X86_64_PC32 .text 0x1C
-// CHECK-NEXT:       0x5AE R_X86_64_PC32 foo   0x0
-// CHECK-NEXT:       0x5C0 R_X86_64_PC32 .text 0x1D
-// CHECK-NEXT:       0x5DE R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x5F4 R_X86_64_PC32 .text 0x1E
-// CHECK-NEXT:       0x612 R_X86_64_PC16 foo   0x0
-// CHECK-NEXT:       0x624 R_X86_64_PC32 .text 0x1F
-// CHECK-NEXT:       0x642 R_X86_64_PC32 foo   0x0
-// CHECK-NEXT:       0x654 R_X86_64_PC32 .text 0x20
-// CHECK-NEXT:       0x672 R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x688 R_X86_64_PC32 .text 0x21
-// CHECK-NEXT:       0x6A6 R_X86_64_PC64 foo   0x0
-// CHECK-NEXT:       0x6BC R_X86_64_PC32 .text 0x22
-// CHECK-NEXT:       0x6E4 R_X86_64_PC32 .text 0x23
+// CHECK-NEXT:       0x1C R_X86_64_PC32 .text 0x23
+// CHECK-NEXT:       0x48 R_X86_64_PC32 .text 0x0
+// CHECK-NEXT:       0x51 R_X86_64_32 bar 0x0
+// CHECK-NEXT:       0x60 R_X86_64_PC32 .text 0x2
+// CHECK-NEXT:       0x69 R_X86_64_32 bar 0x0
+// CHECK-NEXT:       0x83 R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x9C R_X86_64_PC32 .text 0x3
+// CHECK-NEXT:       0xA5 R_X86_64_16 bar 0x0
+// CHECK-NEXT:       0xBB R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0xD4 R_X86_64_PC32 .text 0x1
+// CHECK-NEXT:       0xDD R_X86_64_32 bar 0x0
+// CHECK-NEXT:       0xF6 R_X86_64_16 foo 0x0
+// CHECK-NEXT:       0x108 R_X86_64_PC32 .text 0x4
+// CHECK-NEXT:       0x126 R_X86_64_32 foo 0x0
+// CHECK-NEXT:       0x138 R_X86_64_PC32 .text 0x5
+// CHECK-NEXT:       0x156 R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x16C R_X86_64_PC32 .text 0x6
+// CHECK-NEXT:       0x18A R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x1A0 R_X86_64_PC32 .text 0xA
+// CHECK-NEXT:       0x1BE R_X86_64_16 foo 0x0
+// CHECK-NEXT:       0x1D0 R_X86_64_PC32 .text 0x7
+// CHECK-NEXT:       0x1EE R_X86_64_32 foo 0x0
+// CHECK-NEXT:       0x200 R_X86_64_PC32 .text 0x8
+// CHECK-NEXT:       0x21E R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x234 R_X86_64_PC32 .text 0x9
+// CHECK-NEXT:       0x252 R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x268 R_X86_64_PC32 .text 0xB
+// CHECK-NEXT:       0x286 R_X86_64_PC16 foo 0x0
+// CHECK-NEXT:       0x298 R_X86_64_PC32 .text 0xC
+// CHECK-NEXT:       0x2B6 R_X86_64_PC32 foo 0x0
+// CHECK-NEXT:       0x2C8 R_X86_64_PC32 .text 0xD
+// CHECK-NEXT:       0x2E6 R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x2FC R_X86_64_PC32 .text 0xE
+// CHECK-NEXT:       0x31A R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x330 R_X86_64_PC32 .text 0x12
+// CHECK-NEXT:       0x34E R_X86_64_PC16 foo 0x0
+// CHECK-NEXT:       0x360 R_X86_64_PC32 .text 0xF
+// CHECK-NEXT:       0x37E R_X86_64_PC32 foo 0x0
+// CHECK-NEXT:       0x390 R_X86_64_PC32 .text 0x10
+// CHECK-NEXT:       0x3AE R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x3C4 R_X86_64_PC32 .text 0x11
+// CHECK-NEXT:       0x3E2 R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x3F8 R_X86_64_PC32 .text 0x13
+// CHECK-NEXT:       0x416 R_X86_64_16 foo 0x0
+// CHECK-NEXT:       0x428 R_X86_64_PC32 .text 0x14
+// CHECK-NEXT:       0x446 R_X86_64_32 foo 0x0
+// CHECK-NEXT:       0x458 R_X86_64_PC32 .text 0x15
+// CHECK-NEXT:       0x476 R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x48C R_X86_64_PC32 .text 0x16
+// CHECK-NEXT:       0x4AA R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x4C0 R_X86_64_PC32 .text 0x1A
+// CHECK-NEXT:       0x4DE R_X86_64_16 foo 0x0
+// CHECK-NEXT:       0x4F0 R_X86_64_PC32 .text 0x17
+// CHECK-NEXT:       0x50E R_X86_64_32 foo 0x0
+// CHECK-NEXT:       0x520 R_X86_64_PC32 .text 0x18
+// CHECK-NEXT:       0x53E R_X86_64_64 foo 0x0
+// CHECK-NEXT:       0x554 R_X86_64_PC32 .text 0x19
+// CHECK-NEXT:       0x572 R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x588 R_X86_64_PC32 .text 0x1B
+// CHECK-NEXT:       0x5A6 R_X86_64_PC16 foo 0x0
+// CHECK-NEXT:       0x5B8 R_X86_64_PC32 .text 0x1C
+// CHECK-NEXT:       0x5D6 R_X86_64_PC32 foo 0x0
+// CHECK-NEXT:       0x5E8 R_X86_64_PC32 .text 0x1D
+// CHECK-NEXT:       0x606 R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x61C R_X86_64_PC32 .text 0x1E
+// CHECK-NEXT:       0x63A R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x650 R_X86_64_PC32 .text 0x22
+// CHECK-NEXT:       0x66E R_X86_64_PC16 foo 0x0
+// CHECK-NEXT:       0x680 R_X86_64_PC32 .text 0x1F
+// CHECK-NEXT:       0x69E R_X86_64_PC32 foo 0x0
+// CHECK-NEXT:       0x6B0 R_X86_64_PC32 .text 0x20
+// CHECK-NEXT:       0x6CE R_X86_64_PC64 foo 0x0
+// CHECK-NEXT:       0x6E4 R_X86_64_PC32 .text 0x21
 // CHECK-NEXT:     ]
 // CHECK:        }