[yaml2obj] - Refactor header-sh-fields.yaml test.

[grimar]

Summary

This refines the test to use macros. It is needed for
a follow-up change that adds a functionality to
override more fields.

Also, it is just cleaner to test each key separately.

[jhenderson]

llvm/test/tools/yaml2obj/ELF/header-sh-fields.yaml

6–12

This case isn't really checking the default values any more. It's checking that the default variable values as specified in the YAML are followed, but the purpose of the check seems to me to be to show what happens when the fields aren't specified.

[grimar]

• Addressed review comment.

llvm/test/tools/yaml2obj/ELF/header-sh-fields.yaml

6–12

Fixed.

[jhenderson]

LGTM, with nit.

llvm/test/tools/yaml2obj/ELF/header-sh-fields.yaml

10

and this -> and that this

llvm/test/tools/yaml2obj/ELF/header-sh-fields.yaml

 ## In this test case we check that we can override the default values for
 ## e_shentsize, e_shoff, e_shnum and e_shstrndx fields in the YAML.
 
 ## First we check the default values.
 
-# RUN: yaml2obj --docnum=1 %s -o %t1
-# RUN: llvm-readelf --file-headers %t1 | FileCheck %s --check-prefix=DEFAULT
+# RUN: yaml2obj %s -o %t-default
+# RUN: llvm-readelf --file-headers %t-default | FileCheck %s --check-prefix=DEFAULT
 
-# DEFAULT:   Start of section headers:          88 (bytes into file)
-# DEFAULT:   Size of section headers:           64 (bytes)
-# DEFAULT:   Number of section headers:         3
-# DEFAULT:   Section header string table index: 2
+# DEFAULT: Start of section headers:          88 (bytes into file)
+# DEFAULT: Size of section headers:           64 (bytes)
+# DEFAULT: Number of section headers:         3
+# DEFAULT: Section header string table index: 2
 
 --- !ELF
 FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2LSB
-  Type:    ET_REL
-  Machine: EM_X86_64
+  Class:     ELFCLASS64
+  Data:      ELFDATA2LSB
+  Type:      ET_REL
+  Machine:   EM_X86_64
+  SHEntSize: [[SHENTSIZE=64]]
+  SHOff:     [[SHOFF=88]]
+  SHNum:     [[SHNUM=3]]
+  SHStrNdx:  [[SHSTRNDX=2]]
 
-## Override 3 fields: e_shoff, e_shnum and e_shstrndx. Check the output.
+## Override different fields to check the output produced.
 
-# RUN: yaml2obj --docnum=2 %s -o %t2
-# RUN: llvm-readelf --file-headers %t2 | FileCheck %s --check-prefix=CUSTOM
+## Override the e_shoff field.
+# RUN: yaml2obj %s -DSHOFF=3 -o %t2
+# RUN: llvm-readelf --file-headers %t2 | FileCheck %s --check-prefix=SHOFF
 
-# CUSTOM: Start of section headers:          2 (bytes into file)
-# CUSTOM: Size of section headers:           64 (bytes)
-# CUSTOM: Number of section headers:         3
-# CUSTOM: Section header string table index: 4
+# SHOFF: Start of section headers: 3 (bytes into file)
 
---- !ELF
-FileHeader:
-  Class:     ELFCLASS64
-  Data:      ELFDATA2LSB
-  Type:      ET_REL
-  Machine:   EM_X86_64
-  SHEntSize: 64
-  SHOff:     2
-  SHNum:     3
-  SHStrNdx:  4
+## Override the e_shnum field.
+# RUN: yaml2obj %s -DSHNUM=2 -o %t3
+# RUN: llvm-readelf --file-headers %t3 | FileCheck %s --check-prefix=SHNUM
+
+# SHNUM: Number of section headers: 2{{$}}
+
+## Override the e_shstrndx field.
+# RUN: yaml2obj %s -DSHSTRNDX=4 -o %t4
+# RUN: llvm-readelf --file-headers %t4 | FileCheck %s --check-prefix=SHSTRNDX
 
-## Finally, we use the same YAML as above, but set e_shentsize to 1.
+# SHSTRNDX: Section header string table index: 4{{$}}
+
+## Override the e_shentsize field.
 ## Check the result using raw output from 'od' because llvm-readelf
 ## is unable to dump such headers.
 
-# RUN: yaml2obj --docnum=3 %s -o %t3
-# RUN: od -A n -t x1 -v -j 0x3a -N 1 %t3 | FileCheck %s --check-prefix=NEWSIZE
-# RUN: od -A n -t x1 -v -j 0x3a -N 1 %t2 | FileCheck %s --check-prefix=OLDSIZE
+# RUN: yaml2obj %s -DSHENTSIZE=1 -o %t5
+# RUN: od -A n -t x1 -v -j 0x3a -N 1 %t5 | FileCheck %s --check-prefix=NEWSIZE
+# RUN: od -A n -t x1 -v -j 0x3a -N 1 %t-default | FileCheck %s --check-prefix=OLDSIZE
 # NEWSIZE: 01
 # OLDSIZE: 40
-
---- !ELF
-FileHeader:
-  Class:     ELFCLASS64
-  Data:      ELFDATA2LSB
-  Type:      ET_REL
-  Machine:   EM_X86_64
-  SHEntSize: 1
-  SHOff:     2
-  SHNum:     3
-  SHStrNdx:  4