MIPS: Remove unused J(Label *).

src/mips64/assembler-mips64.cc

Index: src/mips64/assembler-mips64.cc
diff --git a/src/mips64/assembler-mips64.cc b/src/mips64/assembler-mips64.cc
index 2653f4ac33999c1abb59ad60165c16af9fbdc72c..51e85c9bfe6c09a283f11765193b1cd2427af061 100644
--- a/src/mips64/assembler-mips64.cc
+++ b/src/mips64/assembler-mips64.cc
@@ -637,7 +637,7 @@ int Assembler::target_at(int pos, bool is_internal) {
      }
   }
   // Check we have a branch or jump instruction.
-  DCHECK(IsBranch(instr) || IsJ(instr) || IsLui(instr));
+  DCHECK(IsBranch(instr) || IsLui(instr));
   // Do NOT change this to <<2. We rely on arithmetic shifts here, assuming
   // the compiler uses arithmetic shifts for signed integers.
   if (IsBranch(instr)) {
@@ -673,17 +673,8 @@ int Assembler::target_at(int pos, bool is_internal) {
       return pos - delta;
     }
   } else {
-    int32_t imm28 = (instr & static_cast<int32_t>(kImm26Mask)) << 2;
-    if (imm28 == kEndOfJumpChain) {
-      // EndOfChain sentinel is returned directly, not relative to pc or pos.
-      return kEndOfChain;
-    } else {
-      uint64_t instr_address = reinterpret_cast<int64_t>(buffer_ + pos);
-      instr_address &= kImm28Mask;
-      int delta = static_cast<int>(instr_address - imm28);
-      DCHECK(pos > delta);
-      return pos - delta;
-    }
+    UNREACHABLE();
+    return 0;
   }
 }
 
@@ -703,7 +694,7 @@ void Assembler::target_at_put(int pos, int target_pos, bool is_internal) {
     return;
   }
 
-  DCHECK(IsBranch(instr) || IsJ(instr) || IsLui(instr));
+  DCHECK(IsBranch(instr) || IsLui(instr));
   if (IsBranch(instr)) {
     int32_t imm18 = target_pos - (pos + kBranchPCOffset);
     DCHECK((imm18 & 3) == 0);
@@ -734,15 +725,7 @@ void Assembler::target_at_put(int pos, int target_pos, bool is_internal) {
     instr_at_put(pos + 3 * Assembler::kInstrSize,
                  instr_ori2 | (imm & kImm16Mask));
   } else {
-    uint64_t imm28 = reinterpret_cast<uint64_t>(buffer_) + target_pos;
-    imm28 &= kImm28Mask;
-    DCHECK((imm28 & 3) == 0);
-
-    instr &= ~kImm26Mask;
-    uint32_t imm26 = imm28 >> 2;
-    DCHECK(is_uint26(imm26));
-
-    instr_at_put(pos, instr | (imm26 & kImm26Mask));
+    UNREACHABLE();
   }
 }
 
@@ -2596,7 +2579,6 @@ int Assembler::RelocateInternalReference(RelocInfo::Mode rmode, byte* pc,
   }
   Instr instr = instr_at(pc);
   DCHECK(RelocInfo::IsInternalReferenceEncoded(rmode));
-  DCHECK(IsJ(instr) || IsLui(instr));
   if (IsLui(instr)) {
     Instr instr_lui = instr_at(pc + 0 * Assembler::kInstrSize);
     Instr instr_ori = instr_at(pc + 1 * Assembler::kInstrSize);
@@ -2628,21 +2610,8 @@ int Assembler::RelocateInternalReference(RelocInfo::Mode rmode, byte* pc,
                  instr_ori2 | (imm & kImm16Mask));
     return 4;  // Number of instructions patched.
   } else {
-    uint32_t imm28 = (instr & static_cast<int32_t>(kImm26Mask)) << 2;
-    if (static_cast<int32_t>(imm28) == kEndOfJumpChain) {
-      return 0;  // Number of instructions patched.
-    }
-
-    imm28 += pc_delta;
-    imm28 &= kImm28Mask;
-    DCHECK((imm28 & 3) == 0);
-
-    instr &= ~kImm26Mask;
-    uint32_t imm26 = imm28 >> 2;
-    DCHECK(is_uint26(imm26));
-
-    instr_at_put(pc, instr | (imm26 & kImm26Mask));
-    return 1;  // Number of instructions patched.
+    UNREACHABLE();
+    return 0;  // Number of instructions patched.
   }
 }
 
@@ -2916,40 +2885,6 @@ void Assembler::set_target_address_at(Address pc,
 }
 
 
-void Assembler::JumpLabelToJumpRegister(Address pc) {
-  // Address pc points to lui/ori instructions.
-  // Jump to label may follow at pc + 2 * kInstrSize.
-  uint32_t* p = reinterpret_cast<uint32_t*>(pc);
-#ifdef DEBUG
-  Instr instr1 = instr_at(pc);
-#endif
-  Instr instr2 = instr_at(pc + 1 * kInstrSize);
-  Instr instr3 = instr_at(pc + 6 * kInstrSize);
-  bool patched = false;
-
-  if (IsJal(instr3)) {
-    DCHECK(GetOpcodeField(instr1) == LUI);
-    DCHECK(GetOpcodeField(instr2) == ORI);
-
-    uint32_t rs_field = GetRt(instr2) << kRsShift;
-    uint32_t rd_field = ra.code() << kRdShift;  // Return-address (ra) reg.
-    *(p+6) = SPECIAL | rs_field | rd_field | JALR;
-    patched = true;
-  } else if (IsJ(instr3)) {
-    DCHECK(GetOpcodeField(instr1) == LUI);
-    DCHECK(GetOpcodeField(instr2) == ORI);
-
-    uint32_t rs_field = GetRt(instr2) << kRsShift;
-    *(p+6) = SPECIAL | rs_field | JR;
-    patched = true;
-  }
-
-  if (patched) {
-      CpuFeatures::FlushICache(pc+6, sizeof(int32_t));
-  }
-}
-
-
 Handle<ConstantPoolArray> Assembler::NewConstantPool(Isolate* isolate) {
   // No out-of-line constant pool support.
   DCHECK(!FLAG_enable_ool_constant_pool);