[llvm-readobj][test] - Improve section-symbols.test

[grimar]

Summary

section-symbols.test tests how we print section symbols in
different situations.

We might have 2 different cases:

1. A named STT_SECTION symbol.
2. An unnamed STT_SECTION symbol.

Usually section symbols have no name and then --symbols uses their
section names when prints them. If symbol has a name, then it is used.

For --relocations we also want to have this logic probably,
but currently we always ignore symbol names and always use section names.
It is not consistent with GNU readelf and with our logic for --symbols.

This patch refines testing to document the existent behavior and improve
coverage.

[jhenderson]

llvm/test/tools/llvm-readobj/ELF/section-symbols.test

1

98

Ditto below.

115–118

Is there any reason to do this in a separate run? You could do llvm-readobj --symbols --relocations at the same time.

116

I also think that if a name can't be looked up, it shouldn't prevent printing of the relocation. That seems unhelpful to me. Possibly another piece of work, and worth highlighting in the FIXME?

[grimar]

llvm/test/tools/llvm-readobj/ELF/section-symbols.test

115–118

The first test contains constructions like 2> %t.llvm.err1 and then checks the stderr output separatelly for --symbols
I am not sure how much it is useful honestly. I think more useful is to check an exact output to reveal places where we print warnings.
Are you OK if I change 2> %t.llvm.err1 to 2>&1 and merge these tests then?

116

I think it is addressed in D87613: all relocations are dumped there and this FIXME is removed.

[grimar]

• Addressed review comments.

llvm/test/tools/llvm-readobj/ELF/section-symbols.test

115–118

So, I've leaved this place as is for now, but will be happy to merge tests if you think that it is fine.

116

I've updated the FIXME for now though.

[jhenderson]

llvm/test/tools/llvm-readobj/ELF/section-symbols.test

115–118

I think we can merge the tests. I think the motivation for the output being separate before isn't a particularly strong one given the current code state.

[grimar]

• Merged tests.

[jhenderson]

Thanks, LGTM.

llvm/test/tools/llvm-readobj/ELF/section-symbols.test

-## ELF section symbols use the section names when printing. This test verifies
-## this and also that appropriate things are printed if the section is somehow
-## invalid.
+## ELF section symbols use the corresponding section names when printing for
+## unnamed symbols. This test verifies this and also that appropriate things
+## are printed if the section is somehow invalid.
 
+## Test --symbols option.
 # RUN: yaml2obj %s -o %t1
 # RUN: llvm-readobj %t1 --symbols 2> %t.llvm.err1 | FileCheck %s --check-prefix=LLVM1
 # RUN: FileCheck %s --input-file %t.llvm.err1 --check-prefix=WARN1 --implicit-check-not=warning
 # RUN: llvm-readelf %t1 --symbols 2> %t.gnu.err1 | FileCheck %s --check-prefix=GNU1
 # RUN: FileCheck %s --input-file %t.gnu.err1 --check-prefix=WARN1 --implicit-check-not=warning
 
 # LLVM1: Name: (0)
 # LLVM1: Name: .foo (0)
+# LLVM1: Name: symbol1 (25)
 # LLVM1: Name: <section 67> (0)
+# LLVM1: Name: symbol2 (17)
 # LLVM1: Name: .bar (0)
+# LLVM1: Name: symbol3 (9)
 # LLVM1: Name: <section 66> (0)
+# LLVM1: Name: symbol4 (1)
 
-# GNU1:      Symbol table '.symtab' contains 5 entries:
+# GNU1:      Symbol table '.symtab' contains 9 entries:
 # GNU1-NEXT:    Num: {{.*}} Type    {{.*}} Ndx Name
 # GNU1-NEXT:      0: {{.*}} NOTYPE  {{.*}} UND {{$}}
-# GNU1-NEXT:      1: {{.*}} SECTION {{.*}}   1 .foo
-# GNU1-NEXT:      2: {{.*}} SECTION {{.*}}  67 <section 67>
-# GNU1-NEXT:      3: {{.*}} SECTION {{.*}}   2 .bar
-# GNU1-NEXT:      4: {{.*}} SECTION {{.*}}  66 <section 66>
+# GNU1-NEXT:      1: {{.*}} SECTION {{.*}}  1 .foo
+# GNU1-NEXT:      2: {{.*}} SECTION {{.*}}  1 symbol1
+# GNU1-NEXT:      3: {{.*}} SECTION {{.*}} 67 <section 67>
+# GNU1-NEXT:      4: {{.*}} SECTION {{.*}} 67 symbol2
+# GNU1-NEXT:      5: {{.*}} SECTION {{.*}}  2 .bar
+# GNU1-NEXT:      6: {{.*}} SECTION {{.*}}  2 symbol3
+# GNU1-NEXT:      7: {{.*}} SECTION {{.*}} 66 <section 66>
+# GNU1-NEXT:      8: {{.*}} SECTION {{.*}} 66 symbol4
 
 # WARN1: warning: '{{.*}}.tmp1': invalid section index: 67
 # WARN1: warning: '{{.*}}.tmp1': invalid section index: 66
 
 --- !ELF
 FileHeader:
-  Class: ELFCLASS32
-  Data:  ELFDATA2LSB
-  Type:  ET_REL
+  Class:   ELFCLASS32
+  Data:    ELFDATA2LSB
+  Type:    ET_REL
+  Machine: EM_X86_64
 Sections:
   - Name: .foo
     Type: SHT_PROGBITS
   - Name: .bar
     Type: SHT_PROGBITS
   - Name: .symtab_shndx
     Type: SHT_SYMTAB_SHNDX
     Link: .symtab
-    Entries: [ 0, 0, 0, 2, 0x42 ]
+    Entries: [ 0, 0, 0, 0, 0, 2, 2, 0x42, 0x42 ]
+  - Name: .rela.foo
+    Type: SHT_RELA
+    Link: .symtab
+    Info: .foo
+    Relocations:
+      - Offset: 0x1
+        Symbol: 1
+        Type:   R_X86_64_NONE
+      - Offset: 0x2
+        Symbol: 2
+        Type:   R_X86_64_NONE
+      - Offset: 0x3
+        Symbol: 3
+        Type:   R_X86_64_NONE
+      - Offset: 0x4
+        Symbol: 4
+        Type:   R_X86_64_NONE
+      - Offset: 0x5
+        Symbol: 5
+        Type:   R_X86_64_NONE
+      - Offset: 0x6
+        Symbol: 6
+        Type:   R_X86_64_NONE
+      - Offset: 0x7
+        Symbol: 7
+        Type:   R_X86_64_NONE
+      - Offset: 0x8
+        Symbol: 8
+        Type:   R_X86_64_NONE
 Symbols:
+## Case 1: a valid unnamed section symbol.
   - Name: ""
     Section: .foo
     Type: STT_SECTION
+## Case 2: a valid named section symbol.
+  - Name: "symbol1"
+    Section: .foo
+    Type: STT_SECTION
+## Case 3: an unnamed section symbol with invalid index.
   - Name: ""
     Index: 0x43
     Type: STT_SECTION
-  # Section symbol via SHT_SYMTAB_SHNDX.
+## Case 4: a named section symbol with invalid index.
+  - Name: "symbol2"
+    Index: 0x43
+    Type: STT_SECTION
+## Case 5: a valid unnamed section symbol symbol via SHT_SYMTAB_SHNDX.
   - Name: ""
     Index: SHN_XINDEX
     Type: STT_SECTION
-  # Section symbol via SHT_SYMTAB_SHNDX with invalid index.
+## Case 6: a valid named section symbol symbol via SHT_SYMTAB_SHNDX.
+  - Name: "symbol3"
+    Index: SHN_XINDEX
+    Type: STT_SECTION
+## Case 7: a unnamed section symbol via SHT_SYMTAB_SHNDX with invalid index.
   - Name: ""
     Index: SHN_XINDEX
     Type: STT_SECTION
+## Case 8: a named section symbol via SHT_SYMTAB_SHNDX with invalid index.
+  - Name: "symbol4"
+    Index: SHN_XINDEX
+    Type: STT_SECTION
+
+## Test --relocations option.
+## FIXME: relocations should print section symbol names when them are not empty.
+# RUN: llvm-readobj %t1 --relocations 2>&1 | FileCheck %s -DFILE=%t1 --check-prefix=LLVM-RELOCS
+# RUN: llvm-readelf %t1 --relocations 2>&1 | FileCheck %s -DFILE=%t1 --check-prefix=GNU-RELOCS
+
+# LLVM-RELOCS:      Relocations [
+# LLVM-RELOCS-NEXT:   Section (4) .rela.foo {
+# LLVM-RELOCS-NEXT:     0x1 R_X86_64_NONE .foo 0x0
+# LLVM-RELOCS-NEXT:     0x2 R_X86_64_NONE .foo 0x0
+# LLVM-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 3 in SHT_RELA section with index 4: invalid section index: 67
+# LLVM-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 4 in SHT_RELA section with index 4: invalid section index: 67
+# LLVM-RELOCS-NEXT:     0x5 R_X86_64_NONE .bar 0x0
+# LLVM-RELOCS-NEXT:     0x6 R_X86_64_NONE .bar 0x0
+# LLVM-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 7 in SHT_RELA section with index 4: invalid section index: 66
+# LLVM-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 8 in SHT_RELA section with index 4: invalid section index: 66
+# LLVM-RELOCS-NEXT:   }
+# LLVM-RELOCS-NEXT: ]
+
+# GNU-RELOCS:      Relocation section '.rela.foo' at offset 0x58 contains 8 entries:
+# GNU-RELOCS-NEXT:  Offset     Info    Type         Sym. Value  Symbol's Name + Addend
+# GNU-RELOCS-NEXT: 00000001  00000100 R_X86_64_NONE   00000000   .foo + 0
+# GNU-RELOCS-NEXT: 00000002  00000200 R_X86_64_NONE   00000000   .foo + 0
+# GNU-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 3 in SHT_RELA section with index 4: invalid section index: 67
+# GNU-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 4 in SHT_RELA section with index 4: invalid section index: 67
+# GNU-RELOCS-NEXT: 00000005  00000500 R_X86_64_NONE   00000000   .bar + 0
+# GNU-RELOCS-NEXT: 00000006  00000600 R_X86_64_NONE   00000000   .bar + 0
+# GNU-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 7 in SHT_RELA section with index 4: invalid section index: 66
+# GNU-RELOCS-NEXT: warning: '[[FILE]]': unable to print relocation 8 in SHT_RELA section with index 4: invalid section index: 66
 
 # RUN: yaml2obj %s --docnum=2 -o %t2
 # RUN: llvm-readobj %t2 --symbols 2> %t.llvm.err2 | FileCheck %s --check-prefix=LLVM2
 # RUN: FileCheck %s --input-file %t.llvm.err2 --check-prefix=WARN2 --implicit-check-not=warning
 # RUN: llvm-readelf %t2 --symbols 2> %t.gnu.err2 | FileCheck %s --check-prefix=GNU2
 # RUN: FileCheck %s --input-file %t.gnu.err2 --check-prefix=WARN2 --implicit-check-not=warning
 
 # LLVM2: Name: (0)