Improve MIPS support

rui314 · Aug 4, 2023 · 0df6063 · 0df6063
1 parent 5199414
commit 0df6063
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Showing 5 changed files with 48 additions and 21 deletions.
diff --git a/elf/arch-alpha.cc b/elf/arch-alpha.cc
@@ -318,7 +318,7 @@ void AlphaGotSection::copy_buf(Context<E> &ctx) {
 
     if (e.sym->is_imported) {
       *buf = ctx.arg.apply_dynamic_relocs ? e.addend : 0;
-      *dynrel++ = ElfRel<E>(P, E::R_ABS, e.sym->get_dynsym_idx(ctx), e.addend);
+      *dynrel++ = ElfRel<E>(P, E::R_DYNAMIC, e.sym->get_dynsym_idx(ctx), e.addend);
     } else {
       *buf = e.sym->get_addr(ctx) + e.addend;
       if (ctx.arg.pic && !e.sym->is_absolute())

diff --git a/elf/arch-mips64.cc b/elf/arch-mips64.cc
@@ -57,6 +57,7 @@ void EhFrameSection<E>::apply_eh_reloc(Context<E> &ctx, const ElfRel<E> &rel,
   case R_NONE:
     break;
   case R_MIPS_64:
+    assert(rel.r_type2 == R_NONE);
     *(U64<E> *)loc = val;
     break;
   default:
@@ -84,11 +85,11 @@ void InputSection<E>::apply_reloc_alloc(Context<E> &ctx, u8 *base) {
     Symbol<E> &sym = *file.symbols[rel.r_sym];
     u8 *loc = base + rel.r_offset;
 
-    [[maybe_unused]] auto check = [&](i64 val, i64 lo, i64 hi) {
+    auto check = [&](i64 val, i64 lo, i64 hi) {
       if (val < lo || hi <= val)
         Error(ctx) << *this << ": relocation " << rel << " against "
                    << sym << " out of range: " << val << " is not in ["
-                   << lo << ", " << hi << ")";
+                   << lo << ", " << hi << "); recompile with -mxgot";
     };
 
     auto write_combined = [&](u64 val) {
@@ -114,19 +115,25 @@ void InputSection<E>::apply_reloc_alloc(Context<E> &ctx, u8 *base) {
     };
 
     auto write_hi16 = [&](u64 val) {
+      check(val, -(1LL << 31), 1LL << 31);
       if (rel.r_type2 == R_NONE && rel.r_type3 == R_NONE)
         *(U32<E> *)loc |= ((val + BIAS) >> 16) & 0xffff;
       else
         write_combined(val);
     };
 
-    auto write_lo16 = [&](u64 val) {
+    auto write_lo16_nc = [&](u64 val) {
       if (rel.r_type2 == R_NONE && rel.r_type3 == R_NONE)
         *(U32<E> *)loc |= val & 0xffff;
       else
         write_combined(val);
     };
 
+    auto write_lo16 = [&](u64 val) {
+      check(val, -(1 << 15), 1 << 15);
+      write_lo16_nc(val);
+    };
+
     u64 S = sym.get_addr(ctx);
     u64 A = rel.r_addend;
     u64 P = get_addr() + rel.r_offset;
@@ -139,9 +146,9 @@ void InputSection<E>::apply_reloc_alloc(Context<E> &ctx, u8 *base) {
       break;
     case R_MIPS_GPREL16:
       if (sym.is_local(ctx))
-        write_lo16(S + A + GP0 - GP);
+        write_lo16_nc(S + A + GP0 - GP);
       else
-        write_lo16(S + A - GP);
+        write_lo16_nc(S + A - GP);
       break;
     case R_MIPS_GPREL32:
       write32(S + A + GP0 - GP);
@@ -165,15 +172,15 @@ void InputSection<E>::apply_reloc_alloc(Context<E> &ctx, u8 *base) {
       write_lo16(ctx.extra.got->get_gotpage_got_addr(ctx, sym, A) - GP);
       break;
     case R_MIPS_GOT_OFST:
-      write_lo16(S + A - ctx.extra.got->get_gotpage_page_addr(ctx, sym, A));
+      write_lo16(0);
       break;
     case R_MIPS_JALR:
       break;
     case R_MIPS_TLS_TPREL_HI16:
       write_hi16(S + A - ctx.tp_addr);
       break;
     case R_MIPS_TLS_TPREL_LO16:
-      write_lo16(S + A - ctx.tp_addr);
+      write_lo16_nc(S + A - ctx.tp_addr);
       break;
     case R_MIPS_TLS_GOTTPREL:
       write_lo16(sym.get_gottp_addr(ctx) - GP);
@@ -182,13 +189,13 @@ void InputSection<E>::apply_reloc_alloc(Context<E> &ctx, u8 *base) {
       write_hi16(S + A - ctx.dtp_addr);
       break;
     case R_MIPS_TLS_DTPREL_LO16:
-      write_lo16(S + A - ctx.dtp_addr);
+      write_lo16_nc(S + A - ctx.dtp_addr);
       break;
     case R_MIPS_TLS_GD:
-      write_lo16(sym.get_tlsgd_addr(ctx) + A - GP);
+      write_lo16(sym.get_tlsgd_addr(ctx) - GP);
       break;
     case R_MIPS_TLS_LDM:
-      write_lo16(ctx.got->get_tlsld_addr(ctx) + A - GP);
+      write_lo16(ctx.got->get_tlsld_addr(ctx) - GP);
       break;
     default:
       unreachable();
@@ -356,7 +363,7 @@ MipsGotSection<E>::get_got_entries(Context<E> &ctx) const {
   for (const SymbolAddend &ent : got_syms) {
     // If a symbol is imported, let the dynamic linker to resolve it.
     if (ent.sym->is_imported) {
-      add({0, E::R_GLOB_DAT, ent.sym});
+      add({0, E::R_DYNAMIC, ent.sym});
       continue;
     }
 

diff --git a/elf/cmdline.cc b/elf/cmdline.cc
@@ -428,7 +428,7 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
   // It looks like the SPARC's dynamic linker takes both RELA's r_addend
   // and the value at the relocated place. So we don't want to write
   // values to relocated places.
-  if (is_sparc<E>)
+  if constexpr (is_sparc<E>)
     ctx.arg.apply_dynamic_relocs = false;
 
   auto read_arg = [&](std::string name) {
@@ -1216,12 +1216,14 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) {
       Fatal(ctx) << "-auxiliary may not be used without -shared";
   }
 
-  if (!ctx.arg.apply_dynamic_relocs && !E::is_rela)
-    Fatal(ctx) << "--no-apply-dynamic-relocs may not be used on "
-               << E::target_name;
+  if constexpr (!E::is_rela || is_mips<E>)
+    if (!ctx.arg.apply_dynamic_relocs)
+      Fatal(ctx) << "--no-apply-dynamic-relocs may not be used on "
+                 << E::target_name;
 
-  if (is_sparc<E> && ctx.arg.apply_dynamic_relocs)
-    Fatal(ctx) << "--apply-dynamic-relocs may not be used on SPARC64";
+  if constexpr (is_sparc<E>)
+    if (ctx.arg.apply_dynamic_relocs)
+      Fatal(ctx) << "--apply-dynamic-relocs may not be used on SPARC64";
 
   if (!ctx.arg.section_start.empty() && !ctx.arg.section_order.empty())
     Fatal(ctx) << "--section-start may not be used with --section-order";

diff --git a/elf/elf.h b/elf/elf.h
@@ -1866,6 +1866,7 @@ struct X86_64 {
   static constexpr u32 R_GLOB_DAT = R_X86_64_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_X86_64_JUMP_SLOT;
   static constexpr u32 R_ABS = R_X86_64_64;
+  static constexpr u32 R_DYNAMIC = R_X86_64_64;
   static constexpr u32 R_RELATIVE = R_X86_64_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_X86_64_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_X86_64_DTPOFF64;
@@ -1889,6 +1890,7 @@ struct I386 {
   static constexpr u32 R_GLOB_DAT = R_386_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_386_JUMP_SLOT;
   static constexpr u32 R_ABS = R_386_32;
+  static constexpr u32 R_DYNAMIC = R_386_32;
   static constexpr u32 R_RELATIVE = R_386_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_386_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_386_TLS_DTPOFF32;
@@ -1914,6 +1916,7 @@ struct ARM64 {
   static constexpr u32 R_GLOB_DAT = R_AARCH64_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_AARCH64_JUMP_SLOT;
   static constexpr u32 R_ABS = R_AARCH64_ABS64;
+  static constexpr u32 R_DYNAMIC = R_AARCH64_ABS64;
   static constexpr u32 R_RELATIVE = R_AARCH64_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_AARCH64_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_AARCH64_TLS_DTPREL64;
@@ -1939,6 +1942,7 @@ struct ARM32 {
   static constexpr u32 R_GLOB_DAT = R_ARM_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_ARM_JUMP_SLOT;
   static constexpr u32 R_ABS = R_ARM_ABS32;
+  static constexpr u32 R_DYNAMIC = R_ARM_ABS32;
   static constexpr u32 R_RELATIVE = R_ARM_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_ARM_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_ARM_TLS_DTPOFF32;
@@ -1962,6 +1966,7 @@ struct RV64LE {
   static constexpr u32 R_GLOB_DAT = R_RISCV_64;
   static constexpr u32 R_JUMP_SLOT = R_RISCV_JUMP_SLOT;
   static constexpr u32 R_ABS = R_RISCV_64;
+  static constexpr u32 R_DYNAMIC = R_RISCV_64;
   static constexpr u32 R_RELATIVE = R_RISCV_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_RISCV_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_RISCV_TLS_DTPREL64;
@@ -1984,6 +1989,7 @@ struct RV64BE {
   static constexpr u32 R_GLOB_DAT = R_RISCV_64;
   static constexpr u32 R_JUMP_SLOT = R_RISCV_JUMP_SLOT;
   static constexpr u32 R_ABS = R_RISCV_64;
+  static constexpr u32 R_DYNAMIC = R_RISCV_64;
   static constexpr u32 R_RELATIVE = R_RISCV_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_RISCV_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_RISCV_TLS_DTPREL64;
@@ -2006,6 +2012,7 @@ struct RV32LE {
   static constexpr u32 R_GLOB_DAT = R_RISCV_32;
   static constexpr u32 R_JUMP_SLOT = R_RISCV_JUMP_SLOT;
   static constexpr u32 R_ABS = R_RISCV_32;
+  static constexpr u32 R_DYNAMIC = R_RISCV_32;
   static constexpr u32 R_RELATIVE = R_RISCV_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_RISCV_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_RISCV_TLS_DTPREL32;
@@ -2028,6 +2035,7 @@ struct RV32BE {
   static constexpr u32 R_GLOB_DAT = R_RISCV_32;
   static constexpr u32 R_JUMP_SLOT = R_RISCV_JUMP_SLOT;
   static constexpr u32 R_ABS = R_RISCV_32;
+  static constexpr u32 R_DYNAMIC = R_RISCV_32;
   static constexpr u32 R_RELATIVE = R_RISCV_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_RISCV_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_RISCV_TLS_DTPREL32;
@@ -2052,6 +2060,7 @@ struct PPC32 {
   static constexpr u32 R_GLOB_DAT = R_PPC_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_PPC_JMP_SLOT;
   static constexpr u32 R_ABS = R_PPC_ADDR32;
+  static constexpr u32 R_DYNAMIC = R_PPC_ADDR32;
   static constexpr u32 R_RELATIVE = R_PPC_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_PPC_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_PPC_DTPREL32;
@@ -2075,6 +2084,7 @@ struct PPC64V1 {
   static constexpr u32 R_GLOB_DAT = R_PPC64_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_PPC64_JMP_SLOT;
   static constexpr u32 R_ABS = R_PPC64_ADDR64;
+  static constexpr u32 R_DYNAMIC = R_PPC64_ADDR64;
   static constexpr u32 R_RELATIVE = R_PPC64_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_PPC64_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_PPC64_DTPREL64;
@@ -2099,6 +2109,7 @@ struct PPC64V2 {
   static constexpr u32 R_GLOB_DAT = R_PPC64_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_PPC64_JMP_SLOT;
   static constexpr u32 R_ABS = R_PPC64_ADDR64;
+  static constexpr u32 R_DYNAMIC = R_PPC64_ADDR64;
   static constexpr u32 R_RELATIVE = R_PPC64_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_PPC64_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_PPC64_DTPREL64;
@@ -2121,6 +2132,7 @@ struct S390X {
   static constexpr u32 R_GLOB_DAT = R_390_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_390_JMP_SLOT;
   static constexpr u32 R_ABS = R_390_64;
+  static constexpr u32 R_DYNAMIC = R_390_64;
   static constexpr u32 R_RELATIVE = R_390_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_390_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_390_TLS_DTPOFF;
@@ -2143,6 +2155,7 @@ struct SPARC64 {
   static constexpr u32 R_GLOB_DAT = R_SPARC_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_SPARC_JMP_SLOT;
   static constexpr u32 R_ABS = R_SPARC_64;
+  static constexpr u32 R_DYNAMIC = R_SPARC_64;
   static constexpr u32 R_RELATIVE = R_SPARC_RELATIVE;
   static constexpr u32 R_IRELATIVE = R_SPARC_IRELATIVE;
   static constexpr u32 R_DTPOFF = R_SPARC_TLS_DTPOFF64;
@@ -2165,6 +2178,7 @@ struct M68K {
   static constexpr u32 R_GLOB_DAT = R_68K_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_68K_JMP_SLOT;
   static constexpr u32 R_ABS = R_68K_32;
+  static constexpr u32 R_DYNAMIC = R_68K_32;
   static constexpr u32 R_RELATIVE = R_68K_RELATIVE;
   static constexpr u32 R_DTPOFF = R_68K_TLS_DTPREL32;
   static constexpr u32 R_TPOFF = R_68K_TLS_TPREL32;
@@ -2186,6 +2200,7 @@ struct SH4 {
   static constexpr u32 R_GLOB_DAT = R_SH_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_SH_JMP_SLOT;
   static constexpr u32 R_ABS = R_SH_DIR32;
+  static constexpr u32 R_DYNAMIC = R_SH_DIR32;
   static constexpr u32 R_RELATIVE = R_SH_RELATIVE;
   static constexpr u32 R_DTPOFF = R_SH_TLS_DTPOFF32;
   static constexpr u32 R_TPOFF = R_SH_TLS_TPOFF32;
@@ -2207,6 +2222,7 @@ struct ALPHA {
   static constexpr u32 R_GLOB_DAT = R_ALPHA_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_ALPHA_JMP_SLOT;
   static constexpr u32 R_ABS = R_ALPHA_REFQUAD;
+  static constexpr u32 R_DYNAMIC = R_ALPHA_REFQUAD;
   static constexpr u32 R_RELATIVE = R_ALPHA_RELATIVE;
   static constexpr u32 R_DTPOFF = R_ALPHA_DTPREL64;
   static constexpr u32 R_TPOFF = R_ALPHA_TPREL64;
@@ -2227,7 +2243,8 @@ struct MIPS64LE {
   static constexpr u32 R_COPY = R_MIPS_COPY;
   static constexpr u32 R_GLOB_DAT = R_MIPS_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_MIPS_JUMP_SLOT;
-  static constexpr u32 R_ABS = R_MIPS_GLOB_DAT;
+  static constexpr u32 R_ABS = R_MIPS_64;
+  static constexpr u32 R_DYNAMIC = R_MIPS_REL32;
   static constexpr u32 R_RELATIVE = R_MIPS_REL32;
   static constexpr u32 R_DTPOFF = R_MIPS_TLS_DTPREL64;
   static constexpr u32 R_TPOFF = R_MIPS_TLS_TPREL64;
@@ -2248,7 +2265,8 @@ struct MIPS64BE {
   static constexpr u32 R_COPY = R_MIPS_COPY;
   static constexpr u32 R_GLOB_DAT = R_MIPS_GLOB_DAT;
   static constexpr u32 R_JUMP_SLOT = R_MIPS_JUMP_SLOT;
-  static constexpr u32 R_ABS = R_MIPS_GLOB_DAT;
+  static constexpr u32 R_ABS = R_MIPS_64;
+  static constexpr u32 R_DYNAMIC = R_MIPS_REL32;
   static constexpr u32 R_RELATIVE = R_MIPS_REL32;
   static constexpr u32 R_DTPOFF = R_MIPS_TLS_DTPREL64;
   static constexpr u32 R_TPOFF = R_MIPS_TLS_TPREL64;

diff --git a/elf/input-sections.cc b/elf/input-sections.cc
@@ -322,7 +322,7 @@ static void apply_absrel(Context<E> &ctx, InputSection<E> &isec,
   bool writable = (isec.shdr().sh_flags & SHF_WRITE);
 
   auto emit_abs_dynrel = [&] {
-    *dynrel++ = ElfRel<E>(P, E::R_ABS, sym.get_dynsym_idx(ctx), A);
+    *dynrel++ = ElfRel<E>(P, E::R_DYNAMIC, sym.get_dynsym_idx(ctx), A);
     if (ctx.arg.apply_dynamic_relocs)
       *(Word<E> *)loc = A;
   };