Simplified Assembler::target_pointer_address_at.

src/arm/assembler-arm-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 86 matching lines @@
 Address RelocInfo::target_address() {
   ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
   return Assembler::target_address_at(pc_);
 }
 
 
 Address RelocInfo::target_address_address() {
   ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
                               || rmode_ == EMBEDDED_OBJECT
                               || rmode_ == EXTERNAL_REFERENCE);
-  return reinterpret_cast<Address>(Assembler::target_pointer_address_at(pc_));
+  return Assembler::target_pointer_address_at(pc_);
 }
 
 
 int RelocInfo::target_address_size() {
   return kPointerSize;
 }
 
 
 void RelocInfo::set_target_address(Address target, WriteBarrierMode mode) {
   ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
@@ skipping 267 matching lines @@
 
 
 void Assembler::emit(Instr x) {
   CheckBuffer();
   *reinterpret_cast<Instr*>(pc_) = x;
   pc_ += kInstrSize;
 }
 
 
 Address Assembler::target_pointer_address_at(Address pc) {
-  Address target_pc = pc;
-  Instr instr = Memory::int32_at(target_pc);
-  // If we have a bx instruction, the instruction before the bx is
-  // what we need to patch.
-  static const int32_t kBxInstMask = 0x0ffffff0;
-  static const int32_t kBxInstPattern = 0x012fff10;
-  if ((instr & kBxInstMask) == kBxInstPattern) {
-    target_pc -= kInstrSize;
-    instr = Memory::int32_at(target_pc);
-  }
-
-  // With a blx instruction, the instruction before is what needs to be patched.
-  if ((instr & kBlxRegMask) == kBlxRegPattern) {
-    target_pc -= kInstrSize;
-    instr = Memory::int32_at(target_pc);
-  }
-
-  ASSERT(IsLdrPcImmediateOffset(instr));
-  int offset = instr & 0xfff;  // offset_12 is unsigned
-  if ((instr & (1 << 23)) == 0) offset = -offset;  // U bit defines offset sign
-  // Verify that the constant pool comes after the instruction referencing it.
-  ASSERT(offset >= -4);
-  return target_pc + offset + 8;
+  Instr instr = Memory::int32_at(pc);
+  return pc + GetLdrRegisterImmediateOffset(instr) + kPcLoadDelta;
 }
 
 
 Address Assembler::target_pointer_at(Address pc) {
   if (IsMovW(Memory::int32_at(pc))) {
     ASSERT(IsMovT(Memory::int32_at(pc + kInstrSize)));
     Instruction* instr = Instruction::At(pc);
     Instruction* next_instr = Instruction::At(pc + kInstrSize);
     return reinterpret_cast<Address>(
         (next_instr->ImmedMovwMovtValue() << 16) |
         instr->ImmedMovwMovtValue());
   }
+  ASSERT(IsLdrPcImmediateOffset(Memory::int32_at(pc)));
   return Memory::Address_at(target_pointer_address_at(pc));
 }
 
 
 Address Assembler::target_address_from_return_address(Address pc) {
   // Returns the address of the call target from the return address that will
   // be returned to after a call.
   // Call sequence on V7 or later is :
   //  movw  ip, #... @ call address low 16
   //  movt  ip, #... @ call address high 16
@@ skipping 81 matching lines @@
 
 
 void Assembler::set_target_address_at(Address pc, Address target) {
   set_target_pointer_at(pc, target);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_ASSEMBLER_ARM_INL_H_