[llvm-branch-commits] [llvm] fee910e - [libObject, llvm-readelf] - Stop describing a section/segment in `notes_begin()`.

[Georgii Rymar via llvm-branch-commits]

Author: Georgii Rymar
Date: 2020-11-25T12:51:40+03:00
New Revision: fee910e522c997d7606f31148e01bcf67f3f94d1

URL: https://github.com/llvm/llvm-project/commit/fee910e522c997d7606f31148e01bcf67f3f94d1
DIFF: https://github.com/llvm/llvm-project/commit/fee910e522c997d7606f31148e01bcf67f3f94d1.diff

LOG: [libObject,llvm-readelf] - Stop describing a section/segment in `notes_begin()`.

`notes_begin()` is used for iterating over notes. This API in some cases might print
section type and index. At the same time during iterating, the `Elf_Note_Iterator`
might omit it as it doesn't have this info.

Because of above we might have the redundant duplication of information in warnings:
(See D92021).

```
warning: '[[FILE]]': unable to read notes from the SHT_NOTE section with index 1: SHT_NOTE section [index 1] has invalid offset (0x40) or size (0xffff0000)
```

This change stops reporting section index/type in Object/ELF.h/notes_begin().
(FTR, this was introduced by me for llvm-readobj in D64470).
Instead we can describe sections/program headers on the caller side.

Differential revision: https://reviews.llvm.org/D92081

Added: 
    

Modified: 
    llvm/include/llvm/Object/ELF.h
    llvm/test/tools/llvm-readobj/ELF/gnu-notes.test
    llvm/tools/llvm-readobj/ELFDumper.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Object/ELF.h b/llvm/include/llvm/Object/ELF.h
index 7ebe6869c7b5..d47c8f7809fe 100644
--- a/llvm/include/llvm/Object/ELF.h
+++ b/llvm/include/llvm/Object/ELF.h
@@ -238,9 +238,9 @@ class ELFFile {
     assert(Phdr.p_type == ELF::PT_NOTE && "Phdr is not of type PT_NOTE");
     ErrorAsOutParameter ErrAsOutParam(&Err);
     if (Phdr.p_offset + Phdr.p_filesz > getBufSize()) {
-      Err = createError("PT_NOTE header has invalid offset (0x" +
-                        Twine::utohexstr(Phdr.p_offset) + ") or size (0x" +
-                        Twine::utohexstr(Phdr.p_filesz) + ")");
+      Err =
+          createError("invalid offset (0x" + Twine::utohexstr(Phdr.p_offset) +
+                      ") or size (0x" + Twine::utohexstr(Phdr.p_filesz) + ")");
       return Elf_Note_Iterator(Err);
     }
     return Elf_Note_Iterator(base() + Phdr.p_offset, Phdr.p_filesz, Err);
@@ -257,10 +257,9 @@ class ELFFile {
     assert(Shdr.sh_type == ELF::SHT_NOTE && "Shdr is not of type SHT_NOTE");
     ErrorAsOutParameter ErrAsOutParam(&Err);
     if (Shdr.sh_offset + Shdr.sh_size > getBufSize()) {
-      Err = createError("SHT_NOTE section " + getSecIndexForError(*this, Shdr) +
-                        " has invalid offset (0x" +
-                        Twine::utohexstr(Shdr.sh_offset) + ") or size (0x" +
-                        Twine::utohexstr(Shdr.sh_size) + ")");
+      Err =
+          createError("invalid offset (0x" + Twine::utohexstr(Shdr.sh_offset) +
+                      ") or size (0x" + Twine::utohexstr(Shdr.sh_size) + ")");
       return Elf_Note_Iterator(Err);
     }
     return Elf_Note_Iterator(base() + Shdr.sh_offset, Shdr.sh_size, Err);

diff  --git a/llvm/test/tools/llvm-readobj/ELF/gnu-notes.test b/llvm/test/tools/llvm-readobj/ELF/gnu-notes.test
index 04430577daaf..530a4a87293b 100644
--- a/llvm/test/tools/llvm-readobj/ELF/gnu-notes.test
+++ b/llvm/test/tools/llvm-readobj/ELF/gnu-notes.test
@@ -116,7 +116,7 @@ ProgramHeaders:
 # RUN: not llvm-readelf --notes %t2.so 2>&1 | FileCheck -DFILE=%t2.so %s --check-prefix=ERR1
 # RUN: not llvm-readobj --notes %t2.so 2>&1 | FileCheck -DFILE=%t2.so %s --check-prefix=ERR1
 
-# ERR1: error: '[[FILE]]': SHT_NOTE section [index 1] has invalid offset (0xffff0000) or size (0x0)
+# ERR1: error: '[[FILE]]': unable to read notes from the SHT_NOTE section with index 1: invalid offset (0xffff0000) or size (0x0)
 
 --- !ELF
 FileHeader:
@@ -137,7 +137,7 @@ Sections:
 # RUN: not llvm-readelf --notes %t3.so 2>&1 | FileCheck -DFILE=%t3.so %s --check-prefix=ERR2
 # RUN: not llvm-readobj --notes %t3.so 2>&1 | FileCheck -DFILE=%t3.so %s --check-prefix=ERR2
 
-# ERR2: error: '[[FILE]]': SHT_NOTE section [index 1] has invalid offset (0x40) or size (0xffff0000)
+# ERR2: error: '[[FILE]]': unable to read notes from the SHT_NOTE section with index 1: invalid offset (0x40) or size (0xffff0000)
 
 ## Test tools report an error if a note program header has an invalid offset that
 ## goes past the end of file.
@@ -146,7 +146,7 @@ Sections:
 # RUN: not llvm-readelf --notes %t4.so 2>&1 | FileCheck -DFILE=%t4.so %s --check-prefix=ERR3
 # RUN: not llvm-readobj --notes %t4.so 2>&1 | FileCheck -DFILE=%t4.so %s --check-prefix=ERR3
 
-# ERR3: error: '[[FILE]]': PT_NOTE header has invalid offset (0xffff0000) or size (0x0)
+# ERR3: error: '[[FILE]]': unable to read notes from the PT_NOTE segment: invalid offset (0xffff0000) or size (0x0)
 
 --- !ELF
 FileHeader:
@@ -165,7 +165,7 @@ ProgramHeaders:
 # RUN: not llvm-readelf --notes %t5.so 2>&1 | FileCheck -DFILE=%t5.so  %s --check-prefix=ERR4
 # RUN: not llvm-readobj --notes %t5.so 2>&1 | FileCheck -DFILE=%t5.so %s --check-prefix=ERR4
 
-# ERR4: error: '[[FILE]]': PT_NOTE header has invalid offset (0x0) or size (0xffff0000)
+# ERR4: error: '[[FILE]]': unable to read notes from the PT_NOTE segment: invalid offset (0x0) or size (0xffff0000)
 
 ## Check we report a warning when we are unable to locate the PT_NOTE
 ## segment because of broken program headers.

diff  --git a/llvm/tools/llvm-readobj/ELFDumper.cpp b/llvm/tools/llvm-readobj/ELFDumper.cpp
index c5f506bb21f8..e80e2c3db95d 100644
--- a/llvm/tools/llvm-readobj/ELFDumper.cpp
+++ b/llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -5562,7 +5562,10 @@ static void printNotesHelper(
       for (const typename ELFT::Note &Note : Obj.notes(S, Err))
         ProcessNoteFn(Note);
       if (Err)
-        reportError(std::move(Err), Dumper.getElfObject().getFileName());
+        reportError(createError("unable to read notes from the " +
+                                describe(Obj, S) + ": " +
+                                toString(std::move(Err))),
+                    Dumper.getElfObject().getFileName());
       FinishNotesFn();
     }
     return;
@@ -5584,7 +5587,10 @@ static void printNotesHelper(
     for (const typename ELFT::Note Note : Obj.notes(P, Err))
       ProcessNoteFn(Note);
     if (Err)
-      reportError(std::move(Err), Dumper.getElfObject().getFileName());
+      reportError(
+          createError("unable to read notes from the PT_NOTE segment: " +
+                      toString(std::move(Err))),
+          Dumper.getElfObject().getFileName());
     FinishNotesFn();
   }
 }