[ObjectYAML][test] Use a single test file to test the empty 'DWARF' entry.

[Higuoxing]

Summary

This patch addresses comments in D81450

[grimar]

llvm/test/tools/yaml2obj/ELF/DWARF/empty-dwarf-entry.yaml

4

I'd go a bit stricter way here:

You can use llvm-readelf --sections and check the whole section header:

There are 3 section headers, starting at offset 0x58:

Section Headers:
  [Nr] Name
  [ 0]
  [ 1] .strtab
  [ 2] .shstrtab

[jhenderson]

llvm/test/tools/yaml2obj/ELF/DWARF/empty-dwarf-entry.yaml

4

I'm not a massive fan of just relying on --implicit-check-not in a test, as it risks a spelling error or similar strange change. In this case, it's probably fine, but perhaps a suggestion is to also check the number of section headers is as expected (i.e. 3 - null shdr, .strtab and .shstrtab). You can do that using llvm-readelf instead of llvm-readobj, as that includes the number of section headers before the table itself.

[Higuoxing]

Address comments.

[jhenderson]

Looks good, thanks!

llvm/test/tools/yaml2obj/ELF/DWARF/debug-aranges.yaml

debug_aranges:
     - Length:   0x2c
       Version:  2
       CuOffset: 0
       AddrSize: 0x08
       SegSize:  0x00
       Descriptors:
         - Address: 0x0000000000001234
           Length:  0x20
-
-## h) Test that yaml2obj will not generate the .debug_aranges section when the "DWARF" entry
-## exists but the "debug_aranges" entry doesn't exist in the "DWARF" entry or the "Sections" entry.
-
-# RUN: yaml2obj --docnum=8 %s -o %t8.o
-# RUN: llvm-readelf --sections %t8.o | FileCheck /dev/null --implicit-check-not=.debug_aranges
-
---- !ELF
-FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2MSB
-  Type:    ET_EXEC
-  Machine: EM_X86_64
-DWARF:

llvm/test/tools/yaml2obj/ELF/DWARF/debug-line.yaml

- Length:
       DefaultIsStmt:         1
       LineBase:              1
       LineRange:             14
       OpcodeBase:            13
       StandardOpcodeLengths: []
       IncludeDirs:           []
       Files:                 []
       Opcodes:               []
-
-## h) Test that yaml2obj will not generate the .debug_line section when the "DWARF" entry
-## exists but the "debug_line" entry doesn't exist in the "DWARF" entry or the "Sections" entry.
-
-# RUN: yaml2obj --docnum=8 %s -o %t8.o
-# RUN: llvm-readelf --sections %t8.o | FileCheck /dev/null --implicit-check-not=.debug_line
-
---- !ELF
-FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2LSB
-  Type:    ET_EXEC
-  Machine: EM_X86_64
-DWARF:

llvm/test/tools/yaml2obj/ELF/DWARF/debug-ranges.yaml

 DWARF:
   debug_ranges:
     - Offset:   0
       AddrSize: 0x08
       Entries:
         - LowOffset:  0x0000000000000001
           HighOffset: 0x0000000000000002
 
-## h) Test that yaml2obj will not generate the .debug_ranges section when the "DWARF" entry
-## exists but the "debug_ranges" entry doesn't exist in the "DWARF" entry or the "Sections" entry.
-
-# RUN: yaml2obj --docnum=8 %s -o %t8.o
-# RUN: llvm-readelf --sections %t8.o | FileCheck /dev/null --implicit-check-not=.debug_ranges
-
---- !ELF
-FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2LSB
-  Type:    ET_EXEC
-  Machine: EM_X86_64
-DWARF:
-
-## i) Test that yaml2obj emits an error message if we try to assign an invalid offset to an
+## h) Test that yaml2obj emits an error message if we try to assign an invalid offset to an
 ## entry of the '.debug_ranges' section.
 
-# RUN: not yaml2obj --docnum=9 %s -o %t9.o 2>&1 | FileCheck %s --check-prefix=INVALID-OFFSET
+# RUN: not yaml2obj --docnum=8 %s -o %t8.o 2>&1 | FileCheck %s --check-prefix=INVALID-OFFSET
 
 # INVALID-OFFSET: yaml2obj: error: 'Offset' for 'debug_ranges' with index 1 must be greater than or equal to the number of bytes written already (0x20)
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC

llvm/test/tools/yaml2obj/ELF/DWARF/debug-str.yaml

- Name:         .debug_str
     Address:      0x0000000000002020 # 0x00 by default.
     Offset:       0x00000050         # 0x40 for the first section.
 DWARF:
   debug_str:
     - a
     - b
     - c
 
-## h) Test that yaml2obj will not generate the .debug_str section when the "DWARF" entry exists
-## but the "debug_str" entry doesn't exist in the "DWARF" entry or the "Sections" entry.
-
-# RUN: yaml2obj --docnum=8 %s -o %t8.o
-# RUN: llvm-readelf -S %t8.o | FileCheck /dev/null --implicit-check-not=.debug_str
-
---- !ELF
-FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2LSB
-  Type:    ET_EXEC
-  Machine: EM_X86_64
-DWARF:
-
-## i) Test that if we try to initialize the .debug_str section with a "Type" with non-standard
+## h) Test that if we try to initialize the .debug_str section with a "Type" with non-standard
 ## syntax, e.g., SHT_DYNAMIC, yaml2obj will treat it as a dynamic section and discard the
 ## content in the "DWARF" entry.
 
+# RUN: yaml2obj --docnum=8 %s -o %t8.o
+# RUN: llvm-readelf -S %t8.o | FileCheck %s --check-prefix=DYN-SHDR
+# RUN: llvm-readelf -d %t8.o | FileCheck %s --check-prefix=DYNAMIC
+
 # RUN: yaml2obj --docnum=9 %s -o %t9.o
 # RUN: llvm-readelf -S %t9.o | FileCheck %s --check-prefix=DYN-SHDR
 # RUN: llvm-readelf -d %t9.o | FileCheck %s --check-prefix=DYNAMIC
 
-# RUN: yaml2obj --docnum=10 %s -o %t10.o
-# RUN: llvm-readelf -S %t10.o | FileCheck %s --check-prefix=DYN-SHDR
-# RUN: llvm-readelf -d %t10.o | FileCheck %s --check-prefix=DYNAMIC
-
 # DYN-SHDR: Name       Type    Address          Off    Size   ES Flg Lk Inf Al
 # DYN-SHDR: .debug_str DYNAMIC 0000000000000000 000040 000010 10     0  0   0
 
 #      DYNAMIC: Dynamic section at offset 0x40 contains 1 entries:
 # DYNAMIC-NEXT:  Tag                Type   Name/Value
 # DYNAMIC-NEXT:  0x0000000000000000 (NULL) 0x0
 
 --- !ELF

llvm/test/tools/yaml2obj/ELF/DWARF/empty-dwarf-entry.yaml

+## Test that yaml2obj doesn't emit .debug_* sections when the "DWARF" entry is empty.
+
+# RUN: yaml2obj %s -o %t.o
+# RUN: llvm-readobj --sections %t.o | FileCheck /dev/null --implicit-check-not=debug
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+DWARF: