[llvm-readobj][ELF] Teach llvm-readobj to show arch specific ELF section's flags

Some architecture specific ELF section flags might have the same value
(for example SHF_X86_64_LARGE and SHF_HEX_GPREL) and we have to check
machine architectures to select an appropriate set of possible flags.

The patch selects architecture specific flags into separate arrays
`ElfxxxSectionFlags` and combines `ElfSectionFlags` and `ElfxxxSectionFlags`
before pass to the `StreamWriter::printFlags()` method.

Differential Revision: http://reviews.llvm.org/D16269

llvm-svn: 258334

2 files changed, 91 insertions, 1 deletions

diff --git a/llvm/test/Object/obj2yaml.test b/llvm/test/Object/obj2yaml.test
index 60d46a83a52..171488da78f 100644
--- a/llvm/test/Object/obj2yaml.test
+++ b/llvm/test/Object/obj2yaml.test
@@ -327,7 +327,7 @@ ELF-MIPS64EL-NEXT:     Flags:           [ SHF_WRITE, SHF_ALLOC ]
 ELF-MIPS64EL-NEXT:     AddressAlign:    0x0000000000000010
 ELF-MIPS64EL-NEXT:   - Name:            .MIPS.options
 ELF-MIPS64EL-NEXT:     Type:            SHT_MIPS_OPTIONS
-ELF-MIPS64EL-NEXT:     Flags:           [ SHF_ALLOC ]
+ELF-MIPS64EL-NEXT:     Flags:           [ SHF_ALLOC, SHF_MIPS_NOSTRIP ]
 ELF-MIPS64EL-NEXT:     AddressAlign:    0x0000000000000008
 ELF-MIPS64EL-NEXT:     Content:         '01280000000000000000000000000000000000000000000000000000000000000000000000000000'
 ELF-MIPS64EL-NEXT:   - Name:            .pdr
diff --git a/llvm/test/tools/llvm-readobj/elf-sec-flags.test b/llvm/test/tools/llvm-readobj/elf-sec-flags.test
new file mode 100644
index 00000000000..95a417a054f
--- /dev/null
+++ b/llvm/test/tools/llvm-readobj/elf-sec-flags.test
@@ -0,0 +1,90 @@
+# Check that llvm-readobj shows arch specific ELF section flags.
+
+# RUN: yaml2obj -format=elf -docnum 1 %s > %t-amdgpu.o
+# RUN: llvm-readobj -s %t-amdgpu.o | FileCheck -check-prefix=AMD %s
+
+# AMD:      Flags [ (0x300000)
+# AMD-NEXT:   SHF_AMDGPU_HSA_GLOBAL (0x100000)
+# AMD-NEXT:   SHF_AMDGPU_HSA_READONLY (0x200000)
+# AMD-NEXT: ]
+
+# amdgpu.o
+---
+FileHeader:
+  Class:    ELFCLASS64
+  Data:     ELFDATA2LSB
+  OSABI:    ELFOSABI_GNU
+  Type:     ET_REL
+  Machine:  EM_AMDGPU
+  Flags:    []
+Sections:
+  - Name:   .amdgpu
+    Type:   SHT_PROGBITS
+    Flags:  [SHF_AMDGPU_HSA_GLOBAL, SHF_AMDGPU_HSA_READONLY]
+    Size:   4
+
+# RUN: yaml2obj -format=elf -docnum 2 %s > %t-hex.o
+# RUN: llvm-readobj -s %t-hex.o | FileCheck -check-prefix=HEX %s
+
+# HEX:      Flags [ (0x10000000)
+# HEX-NEXT:   SHF_HEX_GPREL (0x10000000)
+# HEX-NEXT: ]
+
+# hex.o
+---
+FileHeader:
+  Class:    ELFCLASS32
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_HEXAGON
+  Flags:    []
+Sections:
+  - Name:   .hex
+    Type:   SHT_PROGBITS
+    Flags:  [SHF_HEX_GPREL]
+    Size:   4
+
+# RUN: yaml2obj -format=elf -docnum 3 %s > %t-mips.o
+# RUN: llvm-readobj -s %t-mips.o | FileCheck -check-prefix=MIPS %s
+
+# MIPS:      Flags [ (0x38000000)
+# MIPS-NEXT:   SHF_MIPS_GPREL (0x10000000)
+# MIPS-NEXT:   SHF_MIPS_MERGE (0x20000000)
+# MIPS-NEXT:   SHF_MIPS_NOSTRIP (0x8000000)
+# MIPS-NEXT: ]
+
+# mips.o
+---
+FileHeader:
+  Class:    ELFCLASS32
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_MIPS
+  Flags:    []
+Sections:
+  - Name:   .mips
+    Type:   SHT_PROGBITS
+    Flags:  [SHF_MIPS_GPREL, SHF_MIPS_MERGE, SHF_MIPS_NOSTRIP]
+    Size:   4
+
+# RUN: yaml2obj -format=elf -docnum 4 %s > %t-x86_64.o
+# RUN: llvm-readobj -s %t-x86_64.o | FileCheck -check-prefix=X86_64 %s
+
+# X86_64:      Flags [ (0x10000000)
+# X86_64-NEXT:   SHF_X86_64_LARGE (0x10000000)
+# X86_64-NEXT: ]
+
+# x86_64.o
+---
+FileHeader:
+  Class:    ELFCLASS64
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_X86_64
+  Flags:    []
+Sections:
+  - Name:   .x86_64
+    Type:   SHT_PROGBITS
+    Flags:  [SHF_X86_64_LARGE]
+    Size:   4
+...