[llvm-readobj] - Teach tool to report error if some section is in multiple COMDAT...

readelf tool reports an error when output contains the same section
in multiple COMDAT groups. That can be useful.
Path teaches llvm-readobj to do the same.

Differential revision: https://reviews.llvm.org/D37567

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313459 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/tools/llvm-readobj/broken-group.test b/test/tools/llvm-readobj/broken-group.test
new file mode 100644 (file)
index 0000000..0de4893
--- /dev/null
+++ b/test/tools/llvm-readobj/broken-group.test
@@ -0,0 +1,77 @@
+# RUN: yaml2obj %s -o %t.o
+
+# RUN: llvm-readobj --elf-section-groups -elf-output-style=GNU \
+# 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:     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:     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:         
+  Local:           
+    - Name:            bar
+      Section:         .group
+    - Name:            zed
+      Section:         .group1

diff --git a/tools/llvm-readobj/ELFDumper.cpp b/tools/llvm-readobj/ELFDumper.cpp
index 4867b473fecaf5ca42cd9cfb0857c11267fc5203..a826e041ecdedf9ff29b6d4ca88bf1a0eff735a1 100644 (file)
--- a/tools/llvm-readobj/ELFDumper.cpp
+++ b/tools/llvm-readobj/ELFDumper.cpp
@@ -18,6 +18,7 @@
 #include "StackMapPrinter.h"
 #include "llvm-readobj.h"
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/PointerIntPair.h"
 #include "llvm/ADT/SmallString.h"
@@ -2489,18 +2490,40 @@ std::vector<GroupSection> getGroups(const ELFFile<ELFT> *Obj) {
   }
   return Ret;
 }
+
+DenseMap<uint64_t, const GroupSection *>
+mapSectionsToGroups(ArrayRef<GroupSection> Groups) {
+  DenseMap<uint64_t, const GroupSection *> Ret;
+  for (const GroupSection &G : Groups)
+    for (const GroupMember &GM : G.Members)
+      Ret.insert({GM.Index, &G});
+  return Ret;
+}
+
 } // namespace
 
 template <class ELFT> void GNUStyle<ELFT>::printGroupSections(const ELFO *Obj) {
   std::vector<GroupSection> V = getGroups<ELFT>(Obj);
+  DenseMap<uint64_t, const GroupSection *> Map = mapSectionsToGroups(V);
   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)
+    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;
+      }
       OS << "   [" << format_decimal(GM.Index, 5) << "]   " << GM.Name << "\n";
+    }
   }
 
   if (V.empty())
@@ -3525,6 +3548,7 @@ template <class ELFT>
 void LLVMStyle<ELFT>::printGroupSections(const ELFO *Obj) {
   DictScope Lists(W, "Groups");
   std::vector<GroupSection> V = getGroups<ELFT>(Obj);
+  DenseMap<uint64_t, const GroupSection *> Map = mapSectionsToGroups(V);
   for (const GroupSection &G : V) {
     DictScope D(W, "Group");
     W.printNumber("Name", G.Name, G.ShName);
@@ -3533,13 +3557,25 @@ void LLVMStyle<ELFT>::printGroupSections(const ELFO *Obj) {
     W.startLine() << "Signature: " << G.Signature << "\n";
 
     ListScope L(W, "Section(s) in group");
-    for (const GroupMember &GM : G.Members)
+    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;
+      }
       W.startLine() << GM.Name << " (" << GM.Index << ")\n";
+    }
   }
 
   if (V.empty())
     W.startLine() << "There are no group sections in the file.\n";
 }
+
 template <class ELFT> void LLVMStyle<ELFT>::printRelocations(const ELFO *Obj) {
   ListScope D(W, "Relocations");