[yaml2obj] - Add a Size tag support for SHT_LLVM_ADDRSIG sections.

[grimar]

Summary

It allows using "Size" with or without "Content" in YAML descriptions of
SHT_LLVM_ADDRSIG sections.

Depends on D68333.

[jhenderson]

One suggestion. Otherwise, looks good.

test/tools/yaml2obj/elf-llvm-addrsig-section.yaml

237

Thinking about it, there probably wants to be a test-case for Size == Content, to show that this exact scenario is also allowed.

[grimar]

• Addressed review comment.

[jhenderson]

LGTM.

include/llvm/ObjectYAML/ELFYAML.h

struct AddrsigSymbol {
   AddrsigSymbol(llvm::yaml::Hex32 Ndx) : Name(None), Index(Ndx){};
   AddrsigSymbol() : Name(None), Index(None){};
   Optional<StringRef> Name;
   Optional<llvm::yaml::Hex32> Index;
 };
 
 struct AddrsigSection : Section {
   Optional<yaml::BinaryRef> Content;
+  Optional<llvm::yaml::Hex64> Size;
   Optional<std::vector<AddrsigSymbol>> Symbols;
 
   AddrsigSection() : Section(SectionKind::Addrsig) {}
   static bool classof(const Section *S) {
     return S->Kind == SectionKind::Addrsig;
   }
 };
 

lib/ObjectYAML/ELFEmitter.cpp

void ELFState<ELFT>::writeSectionContent(Elf_Shdr &SHeader,
                                          ContiguousBlobAccumulator &CBA) {
   raw_ostream &OS =
       CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
 
   unsigned Link = 0;
   if (Section.Link.empty() && SN2I.lookup(".symtab", Link))
     SHeader.sh_link = Link;
 
-  if (Section.Content) {
-    SHeader.sh_size = writeContent(OS, Section.Content, None);
+  if (Section.Content || Section.Size) {
+    SHeader.sh_size = writeContent(OS, Section.Content, Section.Size);
     return;
   }
 
   for (const ELFYAML::AddrsigSymbol &Sym : *Section.Symbols) {
     uint64_t Val =
         Sym.Name ? toSymbolIndex(*Sym.Name, Section.Name, /*IsDynamic=*/false)
                  : (uint32_t)*Sym.Index;
     SHeader.sh_size += encodeULEB128(Val, OS);

lib/ObjectYAML/ELFYAML.cpp

 static void sectionMapping(IO &IO, ELFYAML::SymtabShndxSection &Section) {
   commonSectionMapping(IO, Section);
   IO.mapRequired("Entries", Section.Entries);
 }
 
 static void sectionMapping(IO &IO, ELFYAML::AddrsigSection &Section) {
   commonSectionMapping(IO, Section);
   IO.mapOptional("Content", Section.Content);
+  IO.mapOptional("Size", Section.Size);
   IO.mapOptional("Symbols", Section.Symbols);
 }
 
 void MappingTraits<ELFYAML::SectionOrType>::mapping(
     IO &IO, ELFYAML::SectionOrType &sectionOrType) {
   IO.mapRequired("SectionOrType", sectionOrType.sectionNameOrType);
 }
 
if (const auto *HS = dyn_cast<ELFYAML::HashSection>(Section.get())) {
     }
 
     if ((HS->Bucket && !HS->Chain) || (!HS->Bucket && HS->Chain))
       return "\"Bucket\" and \"Chain\" must be used together";
     return {};
   }
 
   if (const auto *Sec = dyn_cast<ELFYAML::AddrsigSection>(Section.get())) {
-    if (!Sec->Symbols && !Sec->Content)
-      return "one of \"Symbols\" or \"Content\" must be specified";
+    if (!Sec->Symbols && !Sec->Content && !Sec->Size)
+      return "one of \"Content\", \"Size\" or \"Symbols\" must be specified";
+
+    if (Sec->Content || Sec->Size) {
+      if (Sec->Size && Sec->Content &&
+          (uint64_t)*Sec->Size < Sec->Content->binary_size())
+        return "\"Size\" must be greater than or equal to the content "
+               "size";
 
-    if (Sec->Content) {
       if (Sec->Symbols)
-        return "\"Content\" and \"Symbols\" cannot be used together";
+        return "\"Symbols\" cannot be used with \"Content\" or \"Size\"";
       return {};
     }
 
     if (!Sec->Symbols)
       return {};
 
     for (const ELFYAML::AddrsigSymbol &AS : *Sec->Symbols)
       if (AS.Index && AS.Name)

test/tools/yaml2obj/elf-llvm-addrsig-section.yaml

Sections:
   - Name: .llvm_addrsig
     Type: SHT_LLVM_ADDRSIG
     Content: "1122334455"
 
 ## Either "Content" or "Symbols" must be specifed for the SHT_LLVM_ADDRSIG section.
 
 # RUN: not yaml2obj --docnum=7 %s 2>&1 | FileCheck %s --check-prefix=NO-TAGS
 
-# NO-TAGS: error: one of "Symbols" or "Content" must be specified
+# NO-TAGS: error: one of "Content", "Size" or "Symbols" must be specified
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_DYN
   Machine: EM_X86_64
 Sections:
   - Name: .llvm_addrsig
     Type: SHT_LLVM_ADDRSIG
 
 ## "Content" and "Symbols" cannot be used together to describe the SHT_LLVM_ADDRSIG section.
 
 # RUN: not yaml2obj --docnum=8 %s 2>&1 | FileCheck %s --check-prefix=CONTENT-SYMBOLS
 
-# CONTENT-SYMBOLS: error: "Content" and "Symbols" cannot be used together
+# CONTENT-SYMBOLS: "Symbols" cannot be used with "Content" or "Size"
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_DYN
   Machine: EM_X86_64
 Sections:
FileHeader:
   Data:    ELFDATA2LSB
   Type:    ET_DYN
   Machine: EM_X86_64
 Sections:
   - Name: .llvm_addrsig
     Type: SHT_LLVM_ADDRSIG
     Link: 123
     Content: ""
+
+## Check we can use only "Size" to create a SHT_LLVM_ADDRSIG section.
+
+# RUN: yaml2obj --docnum=10 %s -o %t10
+# RUN: llvm-readobj --sections --section-data %t10 | FileCheck %s --check-prefix=SIZE
+
+# SIZE:      Name: .llvm_addrsig
+# SIZE:      Size:
+# SIZE-SAME: 17
+# SIZE:      SectionData (
+# SIZE-NEXT:  0000: 00000000 00000000 00000000 00000000  |
+# SIZE-NEXT:  0010: 00                                   |
+# SIZE-NEXT: )
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+Sections:
+  - Name: .llvm_addrsig
+    Type: SHT_LLVM_ADDRSIG
+    Size: 0x11
+
+## Check we can use "Size" and "Content" together to create a SHT_LLVM_ADDRSIG section.
+
+# RUN: yaml2obj --docnum=11 %s -o %t11
+# RUN: llvm-readobj --sections --section-data %t11 | FileCheck %s --check-prefix=SIZE-CONTENT
+
+# SIZE-CONTENT:      Name: .llvm_addrsig
+# SIZE-CONTENT:      Size:
+# SIZE-CONTENT-SAME: 5
+# SIZE-CONTENT:      SectionData (
+# SIZE-CONTENT-NEXT:  0000: 11223300 00 |
+# SIZE-CONTENT-NEXT: )
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+Sections:
+  - Name: .llvm_addrsig
+    Type: SHT_LLVM_ADDRSIG
+    Size: 0x5
+    Content: "112233"
+
+## Check that when "Size" and "Content" are used together, the size
+## must be greater than or equal to the content size.
+
+# RUN: not yaml2obj --docnum=12 %s 2>&1 | FileCheck %s --check-prefix=SIZE-CONTENT-ERR
+
+# SIZE-CONTENT-ERR: error: "Size" must be greater than or equal to the content size
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+Sections:
+  - Name: .llvm_addrsig
+    Type: SHT_LLVM_ADDRSIG
+    Size: 0x1
+    Content: "1122"
+
+## Check we can't use "Size" and "Symbols" tags together.
+
+# RUN: not yaml2obj --docnum=13 %s 2>&1 | FileCheck %s --check-prefix=CONTENT-SYMBOLS
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+Sections:
+  - Name: .llvm_addrsig
+    Type: SHT_LLVM_ADDRSIG
+    Size: 0x1
+    Symbols: [ ]