[yaml2obj] Align section content using AddressAlign field's value

Use AddressAlign field's value to properly align sections content in the
yaml2obj tool. Before this change the yaml2obj ignored AddressAlign and
always aligned section on 16 bytes boundary.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241674 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Object/yaml2obj-elf-alignment.yaml b/test/Object/yaml2obj-elf-alignment.yaml
new file mode 100644 (file)
index 0000000..8f2f985
--- /dev/null
+++ b/test/Object/yaml2obj-elf-alignment.yaml
@@ -0,0 +1,53 @@
+# Check that yaml2obj takes in account section AddressAlign field.
+
+# RUN: yaml2obj -format=elf %s > %t
+# RUN: llvm-readobj -s %t | FileCheck %s
+
+# CHECK:      Section {
+# CHECK:        Index: 2
+# CHECK-NEXT:   Name: .data
+# CHECK-NEXT:   Type: SHT_PROGBITS
+# CHECK-NEXT:   Flags [
+# CHECK-NEXT:     SHF_ALLOC
+# CHECK-NEXT:     SHF_WRITE
+# CHECK-NEXT:   ]
+# CHECK-NEXT:   Address: 0x0
+# CHECK-NEXT:   Offset: 0x{{[0-9A-F]*}}00
+# CHECK-NEXT:   Size: 4
+# CHECK-NEXT:   Link: 0
+# CHECK-NEXT:   Info: 0
+# CHECK-NEXT:   AddressAlignment: 256
+# CHECK-NEXT:   EntrySize: 0
+# CHECK-NEXT: }
+
+---
+FileHeader:
+  Class:    ELFCLASS32
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_MIPS
+  Flags:    [ EF_MIPS_CPIC, EF_MIPS_ABI_O32, EF_MIPS_ARCH_32 ]
+
+Sections:
+  - Name:          .text
+    Type:          SHT_PROGBITS
+    Flags:         [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:  8
+    Size:          4
+  - Name:          .data
+    Type:          SHT_PROGBITS
+    Flags:         [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:  256
+    Size:          4
+
+Symbols:
+  Global:
+    - Name:     T0
+      Type:     STT_FUNC
+      Section:  .text
+      Size:     4
+    - Name:     D0
+      Type:     STT_OBJECT
+      Section:  .data
+      Size:     4
+...

diff --git a/tools/yaml2obj/yaml2elf.cpp b/tools/yaml2obj/yaml2elf.cpp
index 2cbc338035823889506bac88148a9227afcff289..4940e837367a287ef8e15dfb5d5ef19f0f43ef1a 100644 (file)
--- a/tools/yaml2obj/yaml2elf.cpp
+++ b/tools/yaml2obj/yaml2elf.cpp
@@ -35,6 +35,8 @@ class ContiguousBlobAccumulator {
 
   /// \returns The new offset.
   uint64_t padToAlignment(unsigned Align) {
+    if (Align == 0)
+      Align = 1;
     uint64_t CurrentOffset = InitialOffset + OS.tell();
     uint64_t AlignedOffset = RoundUpToAlignment(CurrentOffset, Align);
     for (; CurrentOffset != AlignedOffset; ++CurrentOffset)
@@ -46,7 +48,7 @@ public:
   ContiguousBlobAccumulator(uint64_t InitialOffset_)
       : InitialOffset(InitialOffset_), Buf(), OS(Buf) {}
   template <class Integer>
-  raw_ostream &getOSAndAlignedOffset(Integer &Offset, unsigned Align = 16) {
+  raw_ostream &getOSAndAlignedOffset(Integer &Offset, unsigned Align) {
     Offset = padToAlignment(Align);
     return OS;
   }
@@ -246,7 +248,7 @@ bool ELFState<ELFT>::initSectionHeaders(std::vector<Elf_Shdr> &SHeaders,
       SHeader.sh_size = S->Size;
       // SHT_NOBITS section does not have content
       // so just to setup the section offset.
-      CBA.getOSAndAlignedOffset(SHeader.sh_offset);
+      CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
     } else
       llvm_unreachable("Unknown section type");
 
@@ -287,8 +289,9 @@ void ELFState<ELFT>::initSymtabSectionHeader(Elf_Shdr &SHeader,
   addSymbols(Doc.Symbols.Global, Syms, ELF::STB_GLOBAL);
   addSymbols(Doc.Symbols.Weak, Syms, ELF::STB_WEAK);
 
-  writeArrayData(CBA.getOSAndAlignedOffset(SHeader.sh_offset),
-                 makeArrayRef(Syms));
+  writeArrayData(
+      CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign),
+      makeArrayRef(Syms));
   SHeader.sh_size = arrayDataSize(makeArrayRef(Syms));
 }
 
@@ -299,7 +302,8 @@ void ELFState<ELFT>::initStrtabSectionHeader(Elf_Shdr &SHeader, StringRef Name,
   zero(SHeader);
   SHeader.sh_name = DotShStrtab.getOffset(Name);
   SHeader.sh_type = ELF::SHT_STRTAB;
-  CBA.getOSAndAlignedOffset(SHeader.sh_offset) << STB.data();
+  CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign)
+      << STB.data();
   SHeader.sh_size = STB.data().size();
   SHeader.sh_addralign = 1;
 }
@@ -337,7 +341,8 @@ ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
                                     ContiguousBlobAccumulator &CBA) {
   assert(Section.Size >= Section.Content.binary_size() &&
          "Section size and section content are inconsistent");
-  raw_ostream &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset);
+  raw_ostream &OS =
+      CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
   Section.Content.writeAsBinary(OS);
   for (auto i = Section.Content.binary_size(); i < Section.Size; ++i)
     OS.write(0);
@@ -364,7 +369,7 @@ ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
   SHeader.sh_entsize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel);
   SHeader.sh_size = SHeader.sh_entsize * Section.Relocations.size();
 
-  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset);
+  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
 
   for (const auto &Rel : Section.Relocations) {
     unsigned SymIdx = 0;
@@ -402,7 +407,7 @@ bool ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
   SHeader.sh_entsize = sizeof(Elf_Word);
   SHeader.sh_size = SHeader.sh_entsize * Section.Members.size();
 
-  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset);
+  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
 
   for (auto member : Section.Members) {
     Elf_Word SIdx;
@@ -433,7 +438,7 @@ bool ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
   SHeader.sh_entsize = sizeof(Flags);
   SHeader.sh_size = SHeader.sh_entsize;
 
-  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset);
+  auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
   Flags.version = Section.Version;
   Flags.isa_level = Section.ISALevel;
   Flags.isa_rev = Section.ISARevision;