[compiler] Remove support for concurrent OSR.

src/full-codegen/ppc/full-codegen-ppc.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/ast/scopes.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 4088 matching lines @@
       //         bge     <ok>            ;; not changed
       //         mov     r12, <interrupt stub address>
       //         mtlr    r12
       //         blrl
       //  <reset profiling counter>
       //  ok-label
       patcher.masm()->cmpi(r6, Operand::Zero());
       break;
     }
     case ON_STACK_REPLACEMENT:
-    case OSR_AFTER_STACK_CHECK:
       //  <decrement profiling counter>
       //         crset
       //         bge     <ok>            ;; not changed
       //         mov     r12, <on-stack replacement address>
       //         mtlr    r12
       //         blrl
       //  <reset profiling counter>
       //  ok-label ----- pc_after points here
 
       // Set the LT bit such that bge is a NOP
       patcher.masm()->crset(Assembler::encode_crbit(cr7, CR_LT));
       break;
   }
 
   // Replace the stack check address in the mov sequence with the
   // entry address of the replacement code.
   Assembler::set_target_address_at(isolate, mov_address, unoptimized_code,
                                    replacement_code->entry());
 
   unoptimized_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
       unoptimized_code, mov_address, replacement_code);
 }
 
 
 BackEdgeTable::BackEdgeState BackEdgeTable::GetBackEdgeState(
     Isolate* isolate, Code* unoptimized_code, Address pc) {
   Address mov_address = Assembler::target_address_from_return_address(pc);
   Address cmp_address = mov_address - 2 * Assembler::kInstrSize;
+#ifdef DEBUG
   Address interrupt_address =
       Assembler::target_address_at(mov_address, unoptimized_code);
+#endif
 
   if (Assembler::IsCmpImmediate(Assembler::instr_at(cmp_address))) {
     DCHECK(interrupt_address == isolate->builtins()->InterruptCheck()->entry());
     return INTERRUPT;
   }
 
   DCHECK(Assembler::IsCrSet(Assembler::instr_at(cmp_address)));
 
-  if (interrupt_address == isolate->builtins()->OnStackReplacement()->entry()) {
-    return ON_STACK_REPLACEMENT;
-  }
-
   DCHECK(interrupt_address ==
-         isolate->builtins()->OsrAfterStackCheck()->entry());
-  return OSR_AFTER_STACK_CHECK;
+         isolate->builtins()->OnStackReplacement()->entry());
+  return ON_STACK_REPLACEMENT;
 }
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_PPC