[yaml2obj] - Allow setting the custom Address for .strtab

[grimar]

Summary

Despite the fact that .strtab is non-allocatable,
there is no reason to disallow setting the custom address
for it.

The patch also adds a test case showing we can set any address
we want for other implicit sections.

Depends on D63136

[jhenderson]

LGTM, with one nit.

test/tools/yaml2obj/implicit-sections-addr.yaml

5

Please add spaces after each ','.

tools/yaml2obj/yaml2elf.cpp

492

If the section

test/tools/yaml2obj/dynsym-dynstr-addr.yaml

-# RUN: yaml2obj %s -o %t
-# RUN: llvm-readobj --sections %t | FileCheck %s
-
-## Check yaml2obj does not ignore the address of the
-## explicitly listed .dynstr and .dynsym sections.
-
-# CHECK:      Name: .dynstr
-# CHECK-NEXT:   Type: SHT_STRTAB
-# CHECK-NEXT:   Flags [
-# CHECK-NEXT:     SHF_ALLOC
-# CHECK-NEXT:   ]
-# CHECK-NEXT:   Address: 0x1000
-
-# CHECK:      Name: .dynsym
-# CHECK-NEXT:   Type: SHT_DYNSYM
-# CHECK-NEXT:   Flags [
-# CHECK-NEXT:     SHF_ALLOC
-# CHECK-NEXT:   ]
-# CHECK-NEXT:   Address: 0x2000
-
-!ELF
-FileHeader:
-  Class:           ELFCLASS64
-  Data:            ELFDATA2LSB
-  Type:            ET_DYN
-  Machine:         EM_X86_64
-Sections:
-  - Name:         .dynstr
-    Type:         SHT_STRTAB
-    Flags:        [ SHF_ALLOC ]
-    Address:      0x1000
-    EntSize:      0x1
-  - Name:         .dynsym
-    Type:         SHT_DYNSYM
-    Flags:        [ SHF_ALLOC ]
-    Address:      0x2000
-    EntSize:      0x18
-DynamicSymbols:
-  - Name:    foo
-    Binding: STB_GLOBAL

test/tools/yaml2obj/implicit-sections-addr.yaml

+# RUN: yaml2obj %s -o %t
+# RUN: llvm-readobj --sections %t | FileCheck %s
+
+## Check yaml2obj does not ignore the address of the
+## explicitly listed .dynstr,.dynsym,.strtab
+## and .symtab sections.
+
+# CHECK:      Name: .dynstr
+# CHECK-NEXT: Type: SHT_STRTAB
+# CHECK-NEXT: Flags [
+# CHECK-NEXT:   SHF_ALLOC
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x1000
+
+# CHECK:      Name: .dynsym
+# CHECK-NEXT:  Type: SHT_DYNSYM
+# CHECK-NEXT:  Flags [
+# CHECK-NEXT:    SHF_ALLOC
+# CHECK-NEXT:  ]
+# CHECK-NEXT:  Address: 0x2000
+
+# CHECK:      Name: .strtab
+# CHECK-NEXT:  Type: SHT_STRTAB
+# CHECK-NEXT:  Flags [
+# CHECK-NEXT:  ]
+# CHECK-NEXT:  Address: 0x3000
+
+# CHECK:      Name: .symtab
+# CHECK-NEXT:  Type: SHT_SYMTAB
+# CHECK-NEXT:  Flags [
+# CHECK-NEXT:  ]
+# CHECK-NEXT:  Address: 0x4000
+
+!ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_DYN
+  Machine: EM_X86_64
+Sections:
+  - Name:    .dynstr
+    Type:    SHT_STRTAB
+    Flags:   [ SHF_ALLOC ]
+    Address: 0x1000
+  - Name:    .dynsym
+    Type:    SHT_DYNSYM
+    Flags:   [ SHF_ALLOC ]
+    Address: 0x2000
+  - Name:    .strtab
+    Type:    SHT_STRTAB
+    Address: 0x3000
+  - Name:    .symtab
+    Type:    SHT_SYMTAB
+    Address: 0x4000
+DynamicSymbols:
+  - Name:    foo
+    Binding: STB_GLOBAL

tools/yaml2obj/yaml2elf.cpp

void ELFState<ELFT>::initStrtabSectionHeader(Elf_Shdr &SHeader, StringRef Name,
   if (YAMLSec && YAMLSec->EntSize)
     SHeader.sh_entsize = *YAMLSec->EntSize;
 
   if (YAMLSec && YAMLSec->Flags)
     SHeader.sh_flags = *YAMLSec->Flags;
   else if (Name == ".dynstr")
     SHeader.sh_flags = ELF::SHF_ALLOC;
 
-  // If .dynstr section is explicitly described in the YAML
+  // If section is explicitly described in the YAML
   // then we want to use its section address.
-  // TODO: Allow this for any explicitly described section.
-  if (YAMLSec && Name == ".dynstr")
+  if (YAMLSec)
     SHeader.sh_addr = YAMLSec->Address;
 }
 
 template <class ELFT>
 void ELFState<ELFT>::setProgramHeaderLayout(std::vector<Elf_Phdr> &PHeaders,
                                             std::vector<Elf_Shdr> &SHeaders) {
   uint32_t PhdrIdx = 0;
   for (auto &YamlPhdr : Doc.ProgramHeaders) {