ARM: clean up code now that ARMv6 is the baseline.

src/arm/assembler-arm-inl.h

Index: src/arm/assembler-arm-inl.h
diff --git a/src/arm/assembler-arm-inl.h b/src/arm/assembler-arm-inl.h
index 0f9630b34154130475b9b1293a8d13e08fc1ba55..1e0d5c1f7dd4a43a24a7e23d243fb4631c58706b 100644
--- a/src/arm/assembler-arm-inl.h
+++ b/src/arm/assembler-arm-inl.h
@@ -266,19 +266,11 @@ Object** RelocInfo::call_object_address() {
 bool RelocInfo::IsPatchedReturnSequence() {
   Instr current_instr = Assembler::instr_at(pc_);
   Instr next_instr = Assembler::instr_at(pc_ + Assembler::kInstrSize);
-#ifdef USE_BLX
   // A patched return sequence is:
   //  ldr ip, [pc, #0]
   //  blx ip
   return ((current_instr & kLdrPCMask) == kLdrPCPattern)
           && ((next_instr & kBlxRegMask) == kBlxRegPattern);
-#else
-  // A patched return sequence is:
-  //  mov lr, pc
-  //  ldr pc, [pc, #-4]
-  return (current_instr == kMovLrPc)
-          && ((next_instr & kLdrPCMask) == kLdrPCPattern);
-#endif
 }
 
 
@@ -408,14 +400,11 @@ Address Assembler::target_pointer_address_at(Address pc) {
     instr = Memory::int32_at(target_pc);
   }
 
-#ifdef USE_BLX
-  // If we have a blx instruction, the instruction before it is
-  // what needs to be patched.
+  // 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);
   }
-#endif
 
   ASSERT(IsLdrPcImmediateOffset(instr));
   int offset = instr & 0xfff;  // offset_12 is unsigned
@@ -442,7 +431,6 @@ Address Assembler::target_pointer_at(Address 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.
-#ifdef USE_BLX
   // Call sequence on V7 or later is :
   //  movw  ip, #... @ call address low 16
   //  movt  ip, #... @ call address high 16
@@ -461,18 +449,10 @@ Address Assembler::target_address_from_return_address(Address pc) {
   ASSERT(IsMovW(Memory::int32_at(candidate)) &&
          IsMovT(Memory::int32_at(candidate + kInstrSize)));
   return candidate;
-#else
-  // Call sequence is:
-  //  mov  lr, pc
-  //  ldr  pc, [pc, #...] @ call address
-  //                      @ return address
-  return pc - kInstrSize;
-#endif
 }
 
 
 Address Assembler::return_address_from_call_start(Address pc) {
-#ifdef USE_BLX
   if (IsLdrPcImmediateOffset(Memory::int32_at(pc))) {
     return pc + kInstrSize * 2;
   } else {
@@ -480,9 +460,6 @@ Address Assembler::return_address_from_call_start(Address pc) {
     ASSERT(IsMovT(Memory::int32_at(pc + kInstrSize)));
     return pc + kInstrSize * 3;
   }
-#else
-  return pc + kInstrSize;
-#endif
 }