[llvm-readobj] Properly decode DF_1_XXX flags

[davide]

Summary

Part 2 of D9955 , i.e. llvm-readobj bits.
It seems that readelf puts a "Flags: " string before the actual flag value for FLAGS1 and not FLAGS, e.g.

0x000000000000001e (FLAGS) ORIGIN BIND_NOW
0x000000006ffffffb (FLAGS_1) Flags: NOW ORIGIN

I personally think this doesn't make a lot of sense and considering llvm-readobj already broke format compatibility w/ GNU readelf (at least the version on my system, 2.17.50), not surrounding among others the type name with braces, I just ignored it, so llvm-readobj -dynamic-table will print something like:

0x000000000000001E FLAGS ORIGIN BIND_NOW
0x000000006FFFFFFB FLAGS_1 NOW ORIGIN

If there are objections, I can change the format.

P.S. Too bad all the tests for llvm-readobj rely on executable, maybe at some point this should be changed, but at least the new test doesn't.

[echristo]

You can also just check in a pre-built one if that makes it easier...

-eric

[davide]

In D9958#177459, @echristo wrote:

You can also just check in a pre-built one if that makes it easier...

-eric

Hi,
it doesn't seem to make a lot of difference here. My preference is for not checking in binaries when possible, but if you think it makes more sense, I'll change the test. The only "problem" I may see here is that this test passes flag to the linker via -Wl, but it seems every reasonably modern linker supports this (and the flags).

[majnemer]

test/tools/llvm-readobj/elf-dtflags.test

4

Check in assembly or an object file, you cannot rely on the existence of clang.

[davide]

Done.
FWIW, there are tests relying on the existence on 'gcc' in the testsuite, so maybe at some point we should document what's allowed to use and what's not (if restrictions are listed somewhere and I missed them, please point them out and sorry in advance for the noise).

[majnemer]

In D9958#177487, @davide wrote:

Done.
FWIW, there are tests relying on the existence on 'gcc' in the testsuite, so maybe at some point we should document what's allowed to use and what's not (if restrictions are listed somewhere and I missed them, please point them out and sorry in advance for the noise).

The test-suite is different from LLVM's tests as they are execution tests. There are no such tests in the test directory.

$ git grep gcc test | grep RUN | wc -l
0

[majnemer]

test/tools/llvm-readobj/elf-dtflags.test

4–7

None of the other llvm-readobj tests have a marker before the lit directives other than tests which run an assembler.

[davide]

David's comments.

test/tools/llvm-readobj/elf-dtflags.test

+// Test that llvm-readobj dumps DF_XXX and DF_1_XXX flags correctly.
+
+RUN: llvm-readobj -dynamic-table %p/Inputs/dtflags.elf-x86-64 | FileCheck %s
+
+CHECK: 0x000000000000001E FLAGS                ORIGIN BIND_NOW
+CHECK: 0x000000006FFFFFFB FLAGS_1              NOW ORIGIN

tools/llvm-readobj/ELFDumper.cpp

 static const char *getTypeString(uint64_t Type) {
   switch (Type) {
   LLVM_READOBJ_TYPE_CASE(BIND_NOW);
   LLVM_READOBJ_TYPE_CASE(DEBUG);
   LLVM_READOBJ_TYPE_CASE(FINI);
   LLVM_READOBJ_TYPE_CASE(FINI_ARRAY);
   LLVM_READOBJ_TYPE_CASE(FINI_ARRAYSZ);
   LLVM_READOBJ_TYPE_CASE(FLAGS);
+  LLVM_READOBJ_TYPE_CASE(FLAGS_1);
   LLVM_READOBJ_TYPE_CASE(HASH);
   LLVM_READOBJ_TYPE_CASE(INIT);
   LLVM_READOBJ_TYPE_CASE(INIT_ARRAY);
   LLVM_READOBJ_TYPE_CASE(INIT_ARRAYSZ);
   LLVM_READOBJ_TYPE_CASE(PREINIT_ARRAY);
   LLVM_READOBJ_TYPE_CASE(PREINIT_ARRAYSZ);
   LLVM_READOBJ_TYPE_CASE(JMPREL);
   LLVM_READOBJ_TYPE_CASE(NEEDED);

 static const EnumEntry<unsigned> ElfDynamicDTFlags[] = {
   LLVM_READOBJ_DT_FLAG_ENT(DF, ORIGIN),
   LLVM_READOBJ_DT_FLAG_ENT(DF, SYMBOLIC),
   LLVM_READOBJ_DT_FLAG_ENT(DF, TEXTREL),
   LLVM_READOBJ_DT_FLAG_ENT(DF, BIND_NOW),
   LLVM_READOBJ_DT_FLAG_ENT(DF, STATIC_TLS)
 };
 
+static const EnumEntry<unsigned> ElfDynamicDTFlags1[] = {
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NOW),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, GLOBAL),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, GROUP),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NODELETE),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, LOADFLTR),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, INITFIRST),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NOOPEN),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, ORIGIN),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, DIRECT),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, TRANS),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, INTERPOSE),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NODEFLIB),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NODUMP),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, CONFALT),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, ENDFILTEE),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, DISPRELDNE),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NODIRECT),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, IGNMULDEF),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NOKSYMS),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NOHDR),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, EDITED),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, NORELOC),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, SYMINTPOSE),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, GLOBAUDIT),
+  LLVM_READOBJ_DT_FLAG_ENT(DF_1, SINGLETON)
+};
+
 static const EnumEntry<unsigned> ElfDynamicDTMipsFlags[] = {
   LLVM_READOBJ_DT_FLAG_ENT(RHF, NONE),
   LLVM_READOBJ_DT_FLAG_ENT(RHF, QUICKSTART),
   LLVM_READOBJ_DT_FLAG_ENT(RHF, NOTPOT),
   LLVM_READOBJ_DT_FLAG_ENT(RHS, NO_LIBRARY_REPLACEMENT),
   LLVM_READOBJ_DT_FLAG_ENT(RHF, NO_MOVE),
   LLVM_READOBJ_DT_FLAG_ENT(RHF, SGI_ONLY),
   LLVM_READOBJ_DT_FLAG_ENT(RHF, GUARANTEE_INIT),

     OS << O->getDynamicString(Value);
     break;
   case DT_MIPS_FLAGS:
     printFlags(Value, makeArrayRef(ElfDynamicDTMipsFlags), OS);
     break;
   case DT_FLAGS:
     printFlags(Value, makeArrayRef(ElfDynamicDTFlags), OS);
     break;
+  case DT_FLAGS_1:
+    printFlags(Value, makeArrayRef(ElfDynamicDTFlags1), OS);
+    break;
   }
 }
 
 template<class ELFT>
 void ELFDumper<ELFT>::printUnwindInfo() {
   W.startLine() << "UnwindInfo not implemented.\n";
 }