[turbofan] Add basic support for calling to (a subset of) C functions.

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/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/mips/macro-assembler-mips.h"
 #include "src/scopes.h"
@@ skipping 445 matching lines @@
         // Check the function's context matches the context argument.
         __ lw(kScratchReg, FieldMemOperand(func, JSFunction::kContextOffset));
         __ Assert(eq, kWrongFunctionContext, cp, Operand(kScratchReg));
       }
 
       AssembleDeconstructActivationRecord();
       __ lw(at, FieldMemOperand(func, JSFunction::kCodeEntryOffset));
       __ Jump(at);
       break;
     }
+    case kArchPrepareCallCFunction: {
+      int const num_parameters = MiscField::decode(instr->opcode());
+      __ PrepareCallCFunction(num_parameters, kScratchReg);
+      break;
+    }
+    case kArchCallCFunction: {
+      int const num_parameters = MiscField::decode(instr->opcode());
+      if (instr->InputAt(0)->IsImmediate()) {
+        ExternalReference ref = i.InputExternalReference(0);
+        __ CallCFunction(ref, num_parameters);
+      } else {
+        Register func = i.InputRegister(0);
+        __ CallCFunction(func, num_parameters);
+      }
+      break;
+    }
     case kArchJmp:
       AssembleArchJump(i.InputRpo(0));
       break;
     case kArchLookupSwitch:
       AssembleArchLookupSwitch(instr);
       break;
     case kArchTableSwitch:
       AssembleArchTableSwitch(instr);
       break;
     case kArchNop:
@@ skipping 865 matching lines @@
       }
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8