[llvm-readelf/readobj] - Fix the behavior when a sections is included in two groups at the same time.

[grimar]

Summary

The current behavior was introduced by me in D37567 and it is a bit strange. It prints the
"Error: ...." message to the errs() manually and stops dumping the group section which has this error.
This behavior is consistent with GNU though, but it is very inconsistent with what the regular llvm-readelf
code usually does/prints, so I suggest to change the implementation:

1. Instead of printing "Error: ...." to errs() - just report a warning.
2. Try to continue dumping the section.
3. Merge broken-group.test to group.text.

This is what this patch does.

[jhenderson]

llvm/test/tools/llvm-readobj/ELF/groups.test

111

included to -> included in

124

Ditto.

[grimar]

• Addressed review comments.

[jhenderson]

LGTM.

llvm/test/tools/llvm-readobj/ELF/broken-group.test

-# RUN: yaml2obj %s -o %t.o
-
-# RUN: llvm-readelf --elf-section-groups \
-# RUN:   %t.o >%tout.log 2>%terr.log
-# RUN: FileCheck %s -check-prefix=GNU-STDERR < %terr.log
-# GNU-STDERR: Error: section [    3] in group section [    4] already in group section [    2]
-# RUN: FileCheck %s -check-prefix=GNU-STDOUT < %tout.log
-# GNU-STDOUT:      COMDAT group section [    2] `.group' [bar] contains 1 sections:
-# GNU-STDOUT-NEXT:   [Index]    Name
-# GNU-STDOUT-NEXT:   [    3]   .foo
-# GNU-STDOUT:      COMDAT group section [    4] `.group1' [zed] contains 1 sections:
-# GNU-STDOUT-NEXT:   [Index]    Name
-
-# RUN: llvm-readobj --elf-section-groups \
-# RUN:   %t.o >%t2out.log 2>%t2err.log %t.o
-# RUN: FileCheck %s -check-prefix=LLVM-STDERR < %t2err.log
-# LLVM-STDERR: Error: .foo (3) in a group .group1 (4) is already in a group .group (2)
-# RUN: FileCheck %s -check-prefix=LLVM-STDOUT < %t2out.log
-# LLVM-STDOUT:      Groups {
-# LLVM-STDOUT-NEXT:   Group {
-# LLVM-STDOUT-NEXT:     Name: .group
-# LLVM-STDOUT-NEXT:     Index: 2
-# LLVM-STDOUT-NEXT:     Link: 5
-# LLVM-STDOUT-NEXT:     Info: 1
-# LLVM-STDOUT-NEXT:     Type: COMDAT
-# LLVM-STDOUT-NEXT:     Signature: bar
-# LLVM-STDOUT-NEXT:     Section(s) in group [
-# LLVM-STDOUT-NEXT:       .foo (3)
-# LLVM-STDOUT-NEXT:     ]
-# LLVM-STDOUT-NEXT:   }
-# LLVM-STDOUT-NEXT:   Group {
-# LLVM-STDOUT-NEXT:     Name: .group1
-# LLVM-STDOUT-NEXT:     Index: 4
-# LLVM-STDOUT-NEXT:     Link: 5
-# LLVM-STDOUT-NEXT:     Info: 2
-# LLVM-STDOUT-NEXT:     Type: COMDAT
-# LLVM-STDOUT-NEXT:     Signature: zed
-# LLVM-STDOUT-NEXT:     Section(s) in group [
-# LLVM-STDOUT-NEXT:     ]
-# LLVM-STDOUT-NEXT:   }
-# LLVM-STDOUT-NEXT: }
-
-!ELF
-FileHeader:      
-  Class:           ELFCLASS64
-  Data:            ELFDATA2LSB
-  Type:            ET_REL
-  Machine:         EM_X86_64
-Sections:        
-  - Name:            .text
-    Type:            SHT_PROGBITS
-    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
-    AddressAlign:    0x0000000000000004
-    Content:         ''
-  - Name:            .group
-    Type:            SHT_GROUP
-    Link:            .symtab
-    AddressAlign:    0x0000000000000004
-    Info:            bar
-    Members:         
-      - SectionOrType:   GRP_COMDAT
-      - SectionOrType:   .foo
-  - Name:            .foo
-    Type:            SHT_PROGBITS
-    Flags:           [ SHF_ALLOC, SHF_EXECINSTR, SHF_GROUP ]
-    AddressAlign:    0x0000000000000001
-    Content:         ''
-  - Name:            .group1
-    Type:            SHT_GROUP
-    Link:            .symtab
-    AddressAlign:    0x0000000000000004
-    Info:            zed
-    Members:         
-      - SectionOrType:   GRP_COMDAT
-      - SectionOrType:   .foo
-Symbols:
-  - Name:            bar
-    Section:         .group
-  - Name:            zed
-    Section:         .group1

llvm/test/tools/llvm-readobj/ELF/groups.test

Members:
       - SectionOrType: .text.foo
       - SectionOrType: .rela.text.foo
   - Name: .group1
     Type: SHT_GROUP
     Link: .symtab
     Info: bar
     Members:
       - SectionOrType: GRP_COMDAT
-      - SectionOrType: .text.bar
+      - SectionOrType: [[TEXTBARNAME=.text.bar]]
       - SectionOrType: .rela.text.bar
   - Name:  .text.foo
     Type:  SHT_PROGBITS
   - Name: .rela.text.foo
     Type: SHT_RELA
     Link: .symtab
     Info: .text.foo
   - Name: .text.bar
     Type: SHT_PROGBITS
   - Name: .rela.text.bar
     Type: SHT_RELA
     Link: .symtab
     Info: .text.bar
 Symbols:
   - Name:    foo
     Section: .text.foo
   - Name:    bar
     Section: .text.bar
+
+## Check that we report a warning and continue dumping when a section is included
+## in two group sections at the same time.
+
+# RUN: yaml2obj %s -DTEXTBARNAME=.text.foo -o %t.dup.o
+# RUN: llvm-readobj --elf-section-groups %t.dup.o 2>&1 | FileCheck %s -DFILE=%t.dup.o --check-prefix=DUP-LLVM
+# RUN: llvm-readelf --elf-section-groups %t.dup.o 2>&1 | FileCheck %s -DFILE=%t.dup.o --check-prefix=DUP-GNU
+
+# DUP-LLVM:      Group {
+# DUP-LLVM-NEXT:   Name: .group
+# DUP-LLVM-NEXT:   Index: 1
+# DUP-LLVM-NEXT:   Link: 7
+# DUP-LLVM-NEXT:   Info: 1
+# DUP-LLVM-NEXT:   Type: COMDAT
+# DUP-LLVM-NEXT:   Signature: foo
+# DUP-LLVM-NEXT:   Section(s) in group [
+# DUP-LLVM-NEXT:     .text.foo (3)
+# DUP-LLVM-NEXT:     .rela.text.foo (4)
+# DUP-LLVM-NEXT:   ]
+# DUP-LLVM-NEXT: }
+# DUP-LLVM:      Group {
+# DUP-LLVM-NEXT:   Name: .group1
+# DUP-LLVM-NEXT:   Index: 2
+# DUP-LLVM-NEXT:   Link: 7
+# DUP-LLVM-NEXT:   Info: 2
+# DUP-LLVM-NEXT:   Type: COMDAT
+# DUP-LLVM-NEXT:   Signature: bar
+# DUP-LLVM-NEXT:   Section(s) in group [
+# DUP-LLVM-NEXT: warning: '[[FILE]]': section with index 3, included in the group section with index 1, was also found in the group section with index 2
+# DUP-LLVM-NEXT:     .text.foo (3)
+# DUP-LLVM-NEXT:     .rela.text.bar (6)
+# DUP-LLVM-NEXT:   ]
+# DUP-LLVM-NEXT: }
+
+# DUP-GNU:      COMDAT group section [    1] `.group' [foo] contains 2 sections:
+# DUP-GNU-NEXT:  [Index]    Name
+# DUP-GNU-NEXT:  [    3]   .text.foo
+# DUP-GNU-NEXT:  [    4]   .rela.text.foo
+
+# DUP-GNU:      COMDAT group section [    2] `.group1' [bar] contains 2 sections:
+# DUP-GNU-NEXT:    [Index]    Name
+# DUP-GNU-NEXT: warning: '[[FILE]]': section with index 3, included in the group section with index 1, was also found in the group section with index 2
+# DUP-GNU-NEXT:    [    3]   .text.foo
+# DUP-GNU-NEXT:    [    6]   .rela.text.bar

llvm/tools/llvm-readobj/ELFDumper.cpp

template <class ELFT> void GNUStyle<ELFT>::printGroupSections(const ELFO *Obj) {
   for (const GroupSection &G : V) {
     OS << "\n"
        << getGroupType(G.Type) << " group section ["
        << format_decimal(G.Index, 5) << "] `" << G.Name << "' [" << G.Signature
        << "] contains " << G.Members.size() << " sections:\n"
        << "   [Index]    Name\n";
     for (const GroupMember &GM : G.Members) {
       const GroupSection *MainGroup = Map[GM.Index];
-      if (MainGroup != &G) {
-        OS.flush();
-        errs() << "Error: section [" << format_decimal(GM.Index, 5)
-               << "] in group section [" << format_decimal(G.Index, 5)
-               << "] already in group section ["
-               << format_decimal(MainGroup->Index, 5) << "]";
-        errs().flush();
-        continue;
-      }
+      if (MainGroup != &G)
+        this->reportUniqueWarning(
+            createError("section with index " + Twine(GM.Index) +
+                        ", included in the group section with index " +
+                        Twine(MainGroup->Index) +
+                        ", was also found in the group section with index " +
+                        Twine(G.Index)));
       OS << "   [" << format_decimal(GM.Index, 5) << "]   " << GM.Name << "\n";
     }
   }
 
   if (V.empty())
     OS << "There are no section groups in this file.\n";
 }
 
for (const GroupSection &G : V) {
     W.printNumber("Link", G.Link);
     W.printNumber("Info", G.Info);
     W.printHex("Type", getGroupType(G.Type), G.Type);
     W.startLine() << "Signature: " << G.Signature << "\n";
 
     ListScope L(W, "Section(s) in group");
     for (const GroupMember &GM : G.Members) {
       const GroupSection *MainGroup = Map[GM.Index];
-      if (MainGroup != &G) {
-        W.flush();
-        errs() << "Error: " << GM.Name << " (" << GM.Index
-               << ") in a group " + G.Name + " (" << G.Index
-               << ") is already in a group " + MainGroup->Name + " ("
-               << MainGroup->Index << ")\n";
-        errs().flush();
-        continue;
-      }
+      if (MainGroup != &G)
+        this->reportUniqueWarning(
+            createError("section with index " + Twine(GM.Index) +
+                        ", included in the group section with index " +
+                        Twine(MainGroup->Index) +
+                        ", was also found in the group section with index " +
+                        Twine(G.Index)));
       W.startLine() << GM.Name << " (" << GM.Index << ")\n";
     }
   }
 
   if (V.empty())
     W.startLine() << "There are no group sections in the file.\n";
 }