MIPS: [Atomics] Remove Atomics code stubs; use TF ops.

src/compiler/mips/code-generator-mips.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.
 
 #include "src/ast/scopes.h"
 #include "src/compiler/code-generator.h"
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/osr.h"
@@ skipping 454 matching lines @@
               Operand(kFloat32ExponentBias + kFloat32MantissaBits));          \
     __ mov_s(i.OutputDoubleRegister(), i.InputDoubleRegister(0));             \
     __ mode##_w_s(i.OutputDoubleRegister(), i.InputDoubleRegister(0));        \
     __ mfc1(at, i.OutputDoubleRegister());                                    \
     __ Branch(USE_DELAY_SLOT, ool->entry(), eq, at, Operand(zero_reg));       \
     __ cvt_s_w(i.OutputDoubleRegister(), i.OutputDoubleRegister());           \
     __ bind(ool->exit());                                                     \
     __ bind(&done);                                                           \
   }
 
+#define ASSEMBLE_ATOMIC_LOAD_INTEGER(asm_instr)          \
+  do {                                                   \
+    __ asm_instr(i.OutputRegister(), i.MemoryOperand()); \
+    __ sync();                                           \
+  } while (0)
+
 void CodeGenerator::AssembleDeconstructFrame() {
   __ mov(sp, fp);
   __ Pop(ra, fp);
 }
 
 void CodeGenerator::AssembleSetupStackPointer() {}
 
 void CodeGenerator::AssembleDeconstructActivationRecord(int stack_param_delta) {
   int sp_slot_delta = TailCallFrameStackSlotDelta(stack_param_delta);
   if (sp_slot_delta > 0) {
@@ skipping 833 matching lines @@
       ASSEMBLE_CHECKED_STORE_FLOAT(Single, swc1);
       break;
     case kCheckedStoreFloat64:
       ASSEMBLE_CHECKED_STORE_FLOAT(Double, sdc1);
       break;
     case kCheckedLoadWord64:
     case kCheckedStoreWord64:
       UNREACHABLE();  // currently unsupported checked int64 load/store.
       break;
     case kAtomicLoadInt8:
+      ASSEMBLE_ATOMIC_LOAD_INTEGER(lb);
+      break;
     case kAtomicLoadUint8:
+      ASSEMBLE_ATOMIC_LOAD_INTEGER(lbu);
+      break;
     case kAtomicLoadInt16:
+      ASSEMBLE_ATOMIC_LOAD_INTEGER(lh);
+      break;
     case kAtomicLoadUint16:
+      ASSEMBLE_ATOMIC_LOAD_INTEGER(lhu);
+      break;
     case kAtomicLoadWord32:
-      // TODO(binji): implement
-      __ nop();
+      ASSEMBLE_ATOMIC_LOAD_INTEGER(lw);
       break;
   }
 }  // NOLINT(readability/fn_size)
 
 
 #define UNSUPPORTED_COND(opcode, condition)                                  \
   OFStream out(stdout);                                                      \
   out << "Unsupported " << #opcode << " condition: \"" << condition << "\""; \
   UNIMPLEMENTED();
 
@@ skipping 595 matching lines @@
       padding_size -= v8::internal::Assembler::kInstrSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8