implement printing out raw section data of xcoff objectfile for llvm-objdump

[DiggerLin]

Summary

implement printing out raw section data of xcoff objectfile for llvm-objdump
and option -D --disassemble-all option for llvm-objdump

[sfertile]

LGTM. A minor suggestion: we could use a test where one of the virtual sections, say .bss is larger then the object file. Similar to X86/elf-disassemble-bss.test.

[leonardchan]

Hi! This patch seems to be causing test failures on our bots (https://luci-milo.appspot.com/p/fuchsia/builders/ci/clang-linux-x64/b8896419822706045584) and the llvm buildbots (http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/12040/steps/ninja%20check%201/logs/FAIL%3A%20LLVM%3A%3Axcoff-disassemble-all.test). Could you take a look into this? Thanks.

[DiggerLin]

In D70255#1750817, @leonardchan wrote:

Hi! This patch seems to be causing test failures on our bots (https://luci-milo.appspot.com/p/fuchsia/builders/ci/clang-linux-x64/b8896419822706045584) and the llvm buildbots (http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/12040/steps/ninja%20check%201/logs/FAIL%3A%20LLVM%3A%3Axcoff-disassemble-all.test). Could you take a look into this? Thanks.

I have fixed the problem.
by adding "; REQUIRES: powerpc-registered-target" into the test case.

[aganea]

llvm/lib/Object/XCOFFObjectFile.cpp

273

This also fails on Windows/MSVC with:

D:\llvm-project\llvm\lib\Object\XCOFFObjectFile.cpp(273): error C2446: ':': no conversion from 'const llvm::support::ubig32_t' to 'const llvm::support::big64_t'
D:\llvm-project\llvm\lib\Object\XCOFFObjectFile.cpp(273): note: No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
D:\llvm-project\llvm\lib\Object\XCOFFObjectFile.cpp(271): error C2789: 'OffsetToRaw': an object of const-qualified type must be initialized
D:\llvm-project\llvm\lib\Object\XCOFFObjectFile.cpp(271): note: see declaration of 'OffsetToRaw'

Casting both FileOffsetToRawData to uint64_t fixes the problem.

[DiggerLin]

llvm/lib/Object/XCOFFObjectFile.cpp

273

I think this is bug of CMVC compiler, I use gcc to compiler it , it success.
I have changed the code to

if (is64Bit())
  OffsetToRaw = toSection64(Sec)->FileOffsetToRawData;
else
  OffsetToRaw = toSection32(Sec)->FileOffsetToRawData;

llvm/lib/Object/XCOFFObjectFile.cpp

Expected<StringRef> XCOFFObjectFile::getSymbolName(DataRefImpl Symb) const {
 
   if (SymEntPtr->NameInStrTbl.Magic != XCOFFSymbolEntry::NAME_IN_STR_TBL_MAGIC)
     return generateXCOFFFixedNameStringRef(SymEntPtr->SymbolName);
 
   return getStringTableEntry(SymEntPtr->NameInStrTbl.Offset);
 }
 
 Expected<uint64_t> XCOFFObjectFile::getSymbolAddress(DataRefImpl Symb) const {
-  uint64_t Result = 0;
-  llvm_unreachable("Not yet implemented!");
-  return Result;
+  assert(!is64Bit() && "Symbol table support not implemented for 64-bit.");
+  return toSymbolEntry(Symb)->Value;
 }
 
 uint64_t XCOFFObjectFile::getSymbolValueImpl(DataRefImpl Symb) const {
   assert(!is64Bit() && "Symbol table support not implemented for 64-bit.");
   return toSymbolEntry(Symb)->Value;
 }
 
 uint64_t XCOFFObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const {
uint64_t XCOFFObjectFile::getSectionSize(DataRefImpl Sec) const {
   if (is64Bit())
     return toSection64(Sec)->SectionSize;
 
   return toSection32(Sec)->SectionSize;
 }
 
 Expected<ArrayRef<uint8_t>>
 XCOFFObjectFile::getSectionContents(DataRefImpl Sec) const {
-  llvm_unreachable("Not yet implemented!");
+  if (isSectionVirtual(Sec))
+    return ArrayRef<uint8_t>();
+
+  const uint64_t OffsetToRaw = is64Bit()
+                                   ? toSection64(Sec)->FileOffsetToRawData
+                                   : toSection32(Sec)->FileOffsetToRawData;
+
+  const uint8_t * ContentStart = base() + OffsetToRaw;
+  uint64_t SectionSize = getSectionSize(Sec);
+  if (checkOffset(Data, uintptr_t(ContentStart), SectionSize))
+    return make_error<BinaryError>();
+
+  return makeArrayRef(ContentStart,SectionSize);
 }
 
 uint64_t XCOFFObjectFile::getSectionAlignment(DataRefImpl Sec) const {
   uint64_t Result = 0;
   llvm_unreachable("Not yet implemented!");
   return Result;
 }
 

 }
 
 bool XCOFFObjectFile::isSectionBSS(DataRefImpl Sec) const {
   uint32_t Flags = getSectionFlags(Sec);
   return Flags & (XCOFF::STYP_BSS | XCOFF::STYP_TBSS);
 }
 
 bool XCOFFObjectFile::isSectionVirtual(DataRefImpl Sec) const {
-  bool Result = false;
-  llvm_unreachable("Not yet implemented!");
-  return Result;
+  return is64Bit() ? toSection64(Sec)->FileOffsetToRawData == 0
+                   : toSection32(Sec)->FileOffsetToRawData == 0;
 }
 
 relocation_iterator XCOFFObjectFile::section_rel_begin(DataRefImpl Sec) const {
   llvm_unreachable("Not yet implemented!");
   return relocation_iterator(RelocationRef());
 }
 
 relocation_iterator XCOFFObjectFile::section_rel_end(DataRefImpl Sec) const {
StringRef XCOFFObjectFile::getFileFormatName() const {
   return is64Bit() ? "aix5coff64-rs6000" : "aixcoff-rs6000";
 }
 
 Triple::ArchType XCOFFObjectFile::getArch() const {
   return is64Bit() ? Triple::ppc64 : Triple::ppc;
 }
 
 SubtargetFeatures XCOFFObjectFile::getFeatures() const {
-  llvm_unreachable("Not yet implemented!");
   return SubtargetFeatures();
 }
 
 bool XCOFFObjectFile::isRelocatableObject() const {
   bool Result = false;
   llvm_unreachable("Not yet implemented!");
   return Result;
 }

llvm/test/tools/llvm-objdump/xcoff-disassemble-all.test

+# RUN: llvm-objdump -D %p/Inputs/xcoff-section-headers.o | \
+# RUN: FileCheck %s
+
+# xcoff-section-headers.o Compiled with IBM XL C/C++ for AIX, V16.1.0
+# compiler command: xlc -qtls -o xcoff-section-headers.o -c test.c
+# test.c:
+# int a;
+# int b = 12345;
+# __thread int c;
+# __thread double d = 3.14159;
+#
+# int func(void)  {
+#   return a;
+# }
+
+CHECK: Inputs/xcoff-section-headers.o:  file format aixcoff-rs6000
+CHECK: Disassembly of section .text:
+CHECK: 00000000 .text:
+CHECK-NEXT:        0: 80 62 00 04                   lwz 3, 4(2)
+CHECK-NEXT:        4: 80 63 00 00                   lwz 3, 0(3)
+CHECK-NEXT:        8: 4e 80 00 20                   blr
+CHECK-NEXT:        c: 00 00 00 00                   <unknown>
+CHECK-NEXT:       10: 00 00 20 40                   <unknown>
+CHECK-NEXT:       14: 00 00 00 01                   <unknown>
+CHECK-NEXT:       18: 00 00 00 0c                   <unknown>
+CHECK-NEXT:       1c: 00 04 66 75                   <unknown>
+CHECK-NEXT:       20: 6e 63 00 00                   xoris 3, 19, 0
+CHECK-NEXT:     ...
+CHECK: Disassembly of section .data:
+CHECK: 00000080 func:
+CHECK-NEXT:       80: 00 00 00 94                   <unknown>
+CHECK: 00000084 a:
+CHECK-NEXT:       84: 00 00 00 a4                   <unknown>
+CHECK: 00000088 b:
+CHECK-NEXT:       88: 00 00 00 a0                   <unknown>
+CHECK: 0000008c c:
+CHECK-NEXT:       8c: 00 00 00 08                   <unknown>
+CHECK: 00000090 d:
+CHECK-NEXT:       90: 00 00 00 00                   <unknown>
+CHECK: 00000094 func:
+CHECK-NEXT:       94: 00 00 00 00                   <unknown>
+CHECK-NEXT:       98: 00 00 00 80                   <unknown>
+CHECK-NEXT:       9c: 00 00 00 00                   <unknown>
+CHECK: 000000a0 b:
+CHECK-NEXT:       a0: 00 00 30 39                   <unknown>
+CHECK: Disassembly of section .bss:
+CHECK: 000000a4 a:
+CHECK-NEXT: ...
+CHECK: Disassembly of section .tdata:
+CHECK: 00000000 d:
+CHECK-NEXT:        0: 40 09 21 f9                   bdnzfl  9, .+8696
+CHECK-NEXT:        4: f0 1b 86 6e                   <unknown>
+CHECK: Disassembly of section .tbss:
+CHECK: 00000008 c:
+CHECK-NEXT: ...

llvm/test/tools/llvm-objdump/xcoff-raw-section-data.test

+# RUN: llvm-objdump --full-contents %p/Inputs/xcoff-section-headers.o | \
+# RUN: FileCheck %s
+
+# CHECK:      Inputs/xcoff-section-headers.o:   file format aixcoff-rs6000
+# CHECK: Contents of section .text:
+# CHECK-NEXT:  0000 80620004 80630000 4e800020 00000000  .b...c..N.. ....
+# CHECK-NEXT:  0010 00002040 00000001 0000000c 00046675  .. @..........fu
+# CHECK-NEXT:  0020 6e630000 00000000 00000000 00000000  nc..............
+# CHECK-NEXT:  0030 00000000 00000000 00000000 00000000  ................
+# CHECK-NEXT:  0040 00000000 00000000 00000000 00000000  ................
+# CHECK-NEXT:  0050 00000000 00000000 00000000 00000000  ................
+# CHECK-NEXT:  0060 00000000 00000000 00000000 00000000  ................
+# CHECK-NEXT:  0070 00000000 00000000 00000000 00000000  ................
+# CHECK-NEXT: Contents of section .data:
+# CHECK-NEXT:  0080 00000094 000000a4 000000a0 00000008  ................
+# CHECK-NEXT:  0090 00000000 00000000 00000080 00000000  ................
+# CHECK-NEXT:  00a0 00003039                             ..09
+# CHECK-NEXT: Contents of section .bss:
+# CHECK-NEXT: <skipping contents of bss section at [00a4, 00a8)>
+# CHECK-NEXT: Contents of section .tdata:
+# CHECK-NEXT:  0000 400921f9 f01b866e                    @.!....n
+# CHECK-NEXT: Contents of section .tbss:
+# CHECK-NEXT: <skipping contents of bss section at [0008, 000c)>
+
+# xcoff-section-headers.o Compiled with IBM XL C/C++ for AIX, V16.1.0
+# compiler command: xlc -qtls -o xcoff-section-headers.o -c test.c
+# test.c:
+# int a;
+# int b = 12345;
+# __thread int c;
+# __thread double d = 3.14159;
+#
+# int func(void)  {
+#   return a;
+# }