elf: add support for csky arch (gimli-rs#561)

Author: Dirreke

src/common.rs

@@ -10,6 +10,7 @@ pub enum Architecture {
     Arm,
     Avr,
     Bpf,
+    Csky,
     I386,
     X86_64,
     #[allow(non_camel_case_types)]
@@ -43,6 +44,7 @@ impl Architecture {
             Architecture::Arm => Some(AddressSize::U32),
             Architecture::Avr => Some(AddressSize::U8),
             Architecture::Bpf => Some(AddressSize::U64),
+            Architecture::Csky => Some(AddressSize::U32),
             Architecture::I386 => Some(AddressSize::U32),
             Architecture::X86_64 => Some(AddressSize::U64),
             Architecture::X86_64_X32 => Some(AddressSize::U32),

src/read/elf/file.rs

@@ -161,6 +161,7 @@ where
             (elf::EM_ARM, _) => Architecture::Arm,
             (elf::EM_AVR, _) => Architecture::Avr,
             (elf::EM_BPF, _) => Architecture::Bpf,
+            (elf::EM_CSKY, _) => Architecture::Csky,
             (elf::EM_386, _) => Architecture::I386,
             (elf::EM_X86_64, false) => Architecture::X86_64_X32,
             (elf::EM_X86_64, true) => Architecture::X86_64,

src/read/elf/relocation.rs

@@ -276,6 +276,11 @@ fn parse_relocation<Elf: FileHeader>(
             elf::R_BPF_64_32 => (RelocationKind::Absolute, 32),
             r_type => (RelocationKind::Elf(r_type), 0),
         },
+        elf::EM_CSKY => match reloc.r_type(endian, false) {
+            elf::R_CKCORE_ADDR32 => (RelocationKind::Absolute, 32),
+            elf::R_CKCORE_PCREL32 => (RelocationKind::Relative, 32),
+            r_type => (RelocationKind::Elf(r_type), 0),
+        },
         elf::EM_386 => match reloc.r_type(endian, false) {
             elf::R_386_32 => (RelocationKind::Absolute, 32),
             elf::R_386_PC32 => (RelocationKind::Relative, 32),

src/write/elf/object.rs

@@ -126,6 +126,7 @@ impl<'a> Object<'a> {
             Architecture::Arm => false,
             Architecture::Avr => true,
             Architecture::Bpf => false,
+            Architecture::Csky => true,
             Architecture::I386 => false,
             Architecture::X86_64 => true,
             Architecture::X86_64_X32 => true,
@@ -329,6 +330,7 @@ impl<'a> Object<'a> {
             Architecture::Arm => elf::EM_ARM,
             Architecture::Avr => elf::EM_AVR,
             Architecture::Bpf => elf::EM_BPF,
+            Architecture::Csky => elf::EM_CSKY,
             Architecture::I386 => elf::EM_386,
             Architecture::X86_64 => elf::EM_X86_64,
             Architecture::X86_64_X32 => elf::EM_X86_64,
@@ -548,6 +550,16 @@ impl<'a> Object<'a> {
                                 return Err(Error(format!("unimplemented relocation {:?}", reloc)));
                             }
                         },
+                        Architecture::Csky => match (reloc.kind, reloc.encoding, reloc.size) {
+                            (RelocationKind::Absolute, _, 32) => elf::R_CKCORE_ADDR32,
+                            (RelocationKind::Relative, RelocationEncoding::Generic, 32) => {
+                                elf::R_CKCORE_PCREL32
+                            }
+                            (RelocationKind::Elf(x), _, _) => x,
+                            _ => {
+                                return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+                            }
+                        },
                         Architecture::I386 => match (reloc.kind, reloc.size) {
                             (RelocationKind::Absolute, 32) => elf::R_386_32,
                             (RelocationKind::Relative, 32) => elf::R_386_PC32,

tests/round_trip/mod.rs

@@ -235,6 +235,7 @@ fn elf_any() {
         (Architecture::Arm, Endianness::Little),
         (Architecture::Avr, Endianness::Little),
         (Architecture::Bpf, Endianness::Little),
+        (Architecture::Csky, Endianness::Little),
         (Architecture::I386, Endianness::Little),
         (Architecture::X86_64, Endianness::Little),
         (Architecture::X86_64_X32, Endianness::Little),