lld/ELF: Parse MSP430 BFD/emulation names

[LemonBoy]

Summary

Follow the naming set by TI's own GCC-based toolchain.
Also, force the osabi field to ELFOSABI_STANDALONE, this matches GNU LD's output (the patching is done in elf32_msp430_post_process_headers).

[LemonBoy]

As usual please merge if no more reviews are needed.

TIA.

lld/ELF/Driver.cpp

std::pair<ELFKind, uint16_t> ret =
           .Case("elf64ltsmip", {ELF64LEKind, EM_MIPS})
           .Case("elf64lriscv", {ELF64LEKind, EM_RISCV})
           .Case("elf64ppc", {ELF64BEKind, EM_PPC64})
           .Case("elf64lppc", {ELF64LEKind, EM_PPC64})
           .Cases("elf_amd64", "elf_x86_64", {ELF64LEKind, EM_X86_64})
           .Case("elf_i386", {ELF32LEKind, EM_386})
           .Case("elf_iamcu", {ELF32LEKind, EM_IAMCU})
           .Case("elf64_sparc", {ELF64BEKind, EM_SPARCV9})
+          .Case("msp430elf", {ELF32LEKind, EM_MSP430})
           .Default({ELFNoneKind, EM_NONE});
 
   if (ret.first == ELFNoneKind)
     error("unknown emulation: " + emul);
+  if (ret.second == EM_MSP430)
+    osabi = ELFOSABI_STANDALONE;
   return std::make_tuple(ret.first, ret.second, osabi);
 }
 
 // Returns slices of MB by parsing MB as an archive file.
 // Each slice consists of a member file in the archive.
 std::vector<std::pair<MemoryBufferRef, uint64_t>> static getArchiveMembers(
     MemoryBufferRef mb) {
   std::unique_ptr<Archive> file =

lld/ELF/ScriptParser.cpp

return StringSwitch<std::pair<ELFKind, uint16_t>>(s)
       .Case("elf32-ntradbigmips", {ELF32BEKind, EM_MIPS})
       .Case("elf32-tradlittlemips", {ELF32LEKind, EM_MIPS})
       .Case("elf32-ntradlittlemips", {ELF32LEKind, EM_MIPS})
       .Case("elf64-tradbigmips", {ELF64BEKind, EM_MIPS})
       .Case("elf64-tradlittlemips", {ELF64LEKind, EM_MIPS})
       .Case("elf32-littleriscv", {ELF32LEKind, EM_RISCV})
       .Case("elf64-littleriscv", {ELF64LEKind, EM_RISCV})
       .Case("elf64-sparc", {ELF64BEKind, EM_SPARCV9})
+      .Case("elf32-msp430", {ELF32LEKind, EM_MSP430})
       .Default({ELFNoneKind, EM_NONE});
 }
 
 // Parse OUTPUT_FORMAT(bfdname) or OUTPUT_FORMAT(bfdname, big, little).
 // Currently we ignore big and little parameters.
 void ScriptParser::readOutputFormat() {
   expect("(");
 
   config->bfdname = unquote(next());
   StringRef s = config->bfdname;
   if (s.consume_back("-freebsd"))
     config->osabi = ELFOSABI_FREEBSD;
 
   std::tie(config->ekind, config->emachine) = parseBfdName(s);
   if (config->emachine == EM_NONE)
     setError("unknown output format name: " + config->bfdname);
   if (s == "elf32-ntradlittlemips" || s == "elf32-ntradbigmips")
     config->mipsN32Abi = true;
+  if (config->emachine == EM_MSP430)
+    config->osabi = ELFOSABI_STANDALONE;
 
   if (consume(")"))
     return;
   expect(",");
   skip();
   expect(",");
   skip();
   expect(")");

lld/test/ELF/emulation-msp430.s

+# REQUIRES: msp430
+# RUN: llvm-mc -filetype=obj -triple=msp430 %s -o %t.o
+# RUN: ld.lld %t.o -o %t1
+# RUN: llvm-readobj --file-headers %t1 | FileCheck %s
+# RUN: ld.lld -m msp430elf %t.o -o %t2
+# RUN: cmp %t1 %t2
+# RUN: echo 'OUTPUT_FORMAT(elf32-msp430)' > %t.lds
+# RUN: ld.lld -T %t.lds %t.o -o %t3
+# RUN: llvm-readobj --file-headers %t3 | FileCheck %s
+
+# CHECK:      ElfHeader {
+# CHECK-NEXT:   Ident {
+# CHECK-NEXT:     Magic: (7F 45 4C 46)
+# CHECK-NEXT:     Class: 32-bit (0x1)
+# CHECK-NEXT:     DataEncoding: LittleEndian (0x1)
+# CHECK-NEXT:     FileVersion: 1
+# CHECK-NEXT:     OS/ABI: Standalone (0xFF)
+# CHECK-NEXT:     ABIVersion: 0
+# CHECK-NEXT:     Unused: (00 00 00 00 00 00 00)
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Type: Executable (0x2)
+# CHECK-NEXT:   Machine: EM_MSP430 (0x69)
+# CHECK-NEXT:   Version: 1
+
+.globl _start
+_start: