[ELF][test] Add some additional .eh_frame/.eh_frame_hdr testing

[jhenderson]

Summary

This patch adds a few extra cases to the existing testing for eh_frame and eh_frame_hdr behaviour in LLD. They all come from a private testsuite we are trying to migrate to lit.

[grimar]

lld/test/ELF/eh-frame-hdr-comdat.s

14

Perhaps show the full output? (it is not that clear what is the "garbage" you're reffering to. Given that there is no garbage in the output, showing the full output is probably better).

Contents of section .eh_frame_hdr:
 200158 011b033b 14000000 01000000 4c100000
 200168 30000000

Or may be it is even better to use llvm-readobj -u, which shows both size and the number of FDEs (and explains all fields):

EHFrameHeader {
  Address: 0x200158
  Offset: 0x158
  Size: 0x14
  Corresponding Section: .eh_frame_hdr
  Header {
    version: 1
    eh_frame_ptr_enc: 0x1b
    fde_count_enc: 0x3
    table_enc: 0x3b
    eh_frame_ptr: 0x200170
    fde_count: 1
    entry 0 {
      initial_location: 0x2011a4
      address: 0x200188
    }
  }
}

lld/test/ELF/eh-frame-type.test

1

Use yaml2obj -DTYPE=SHT_X86_64_UNWIND instead?

[jhenderson]

lld/test/ELF/eh-frame-hdr-comdat.s

14

This is basically a copy of eh-frame-hdr-icf.s, with a different inptu, hence the style. I don't mind updating it though.

lld/test/ELF/eh-frame-type.test

1

Makes sense. Not sure why I didn't think of that before!

[MaskRay]

I made a rough check that this does not duplicate existing tests. So the addition is good.

lld/test/ELF/eh-frame-hdr-comdat.s

16

,unique,0 is not needed.

lld/test/ELF/eh-frame-merge.s

6

///

[jhenderson]

Address review comments:

• Use full output for eh_frame_hdr check (also match up addresses to show the output is correct).
• Changed comment marker.
• Used yaml2obj -D option.
• Removed extraneous unique directive caused by copy/paste.

[grimar]

LGTM

[MaskRay]

Thanks!

lld/test/ELF/eh-frame-type.test

8

Might be good adding another test ld.lld %t1.o %t2.o - check the two types can be mixed (clang assembled .o and GNU as assembled .o can be mixed)

Context: D76151

[MaskRay]

lld/test/ELF/eh-frame-hdr-comdat.s

4

-unknown-linux can be omitted (we are testing generic ELF behavior, not specific to Linux)

[jhenderson]

Tidy up YAML, add additional case for mixing .eh_frame of different types and simplify llvm-mc call.

lld/test/ELF/eh-frame-hdr-comdat.s

+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: ld.lld %t %t -o %t2 --eh-frame-hdr
+# RUN: llvm-objdump -s --section-headers %t2 | FileCheck %s
+
+## Check .eh_frame_hdr contains single FDE and no garbage data at tail.
+# CHECK: Sections:
+# CHECK: Idx Name          Size
+# CHECK:     .eh_frame_hdr 00000014
+
+# CHECK: Contents of section .eh_frame_hdr:
+# CHECK-NEXT: 200158 011b033b 14000000 01000000
+##                                     ^ FDE count
+
+.section .text.bar,"axG",@progbits,bar,comdat,unique,0
+.global bar
+bar:
+.cfi_startproc
+    ret
+.cfi_endproc

lld/test/ELF/eh-frame-merge.s

 // REQUIRES: x86
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 // RUN: ld.lld --hash-style=sysv %t.o %t.o -o %t -shared
 // RUN: llvm-readobj -S --section-data %t | FileCheck %s
 
+// Also show that the merging happens when going via a -r link.
+// RUN: ld.lld -r %t.o %t.o -o %t.r.o
+// RUN: ld.lld --hash-style=sysv %t.r.o -o %t2 -shared
+// RUN: llvm-readobj -S --section-data %t2 | FileCheck %s
+
         .section  foo,"ax",@progbits
   .cfi_startproc
         nop
   .cfi_endproc
 
         .section  bar,"axG",@progbits,foo,comdat
         .cfi_startproc
         nop

lld/test/ELF/eh-frame-type.test

-# RUN: yaml2obj %s -o %t.o
-# RUN: ld.lld %t.o -o %t -shared
-# RUN: llvm-readobj -S %t | FileCheck %s
+# RUN: yaml2obj %s -o %t1.o --docnum=1
+# RUN: ld.lld %t1.o -o %t1 -shared
+# RUN: llvm-readobj -S %t1 | FileCheck %s
+
+# RUN: yaml2obj %s -o %t2.o --docnum=2
+# RUN: ld.lld %t2.o -o %t2 -shared
+# RUN: llvm-readobj -S %t2 | FileCheck %s
 
 # CHECK:      Name: .eh_frame
 # CHECK-NEXT: Type: SHT_PROGBITS
 
-!ELF
+--- !ELF
 FileHeader:
   Class:           ELFCLASS64
   Data:            ELFDATA2LSB
   Type:            ET_REL
   Machine:         EM_X86_64
 Sections:
   - Name:            .eh_frame
     Type:            SHT_PROGBITS
     Flags:           [ SHF_ALLOC ]
+
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .eh_frame
+    Type:            SHT_X86_64_UNWIND
+    Flags:           [ SHF_ALLOC ]