MIPS: Allow function inlining with context change.

Port r17019 (cd4b69cd)

BUG=
R=jkummerow@chromium.org, plind44@gmail.com

Review URL: https://codereview.chromium.org/25622003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17070 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen.cc

@@ -6366,7 +6366,7 @@ bool HOptimizedGraphBuilder::TryInline(CallKind call_kind,
     return false;
   }
 
-#if !V8_TARGET_ARCH_IA32 && !V8_TARGET_ARCH_ARM
+#if !V8_TARGET_ARCH_IA32 && !V8_TARGET_ARCH_ARM && !V8_TARGET_ARCH_MIPS
   // Target must be able to use caller's context.
   CompilationInfo* outer_info = current_info();
   if (target->context() != outer_info->closure()->context() ||
@@ -6515,9 +6515,9 @@ bool HOptimizedGraphBuilder::TryInline(CallKind call_kind,
                                      undefined,
                                      function_state()->inlining_kind(),
                                      undefined_receiver);
-#if V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_ARM
-  // IA32 and ARM only, overwrite the caller's context in the deoptimization
-  // environment with the correct one.
+#if V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_ARM || V8_TARGET_ARCH_MIPS
+  // IA32, ARM and MIPS only, overwrite the caller's context in the
+  // deoptimization environment with the correct one.
   //
   // TODO(kmillikin): implement the same inlining on other platforms so we
   // can remove the unsightly ifdefs in this function.

src/mips/lithium-codegen-mips.cc

@@ -732,6 +732,10 @@ void LCodeGen::LoadContextFromDeferred(LOperand* context) {
     __ Move(cp, ToRegister(context));
   } else if (context->IsStackSlot()) {
     __ lw(cp, ToMemOperand(context));
+  } else if (context->IsConstantOperand()) {
+    HConstant* constant =
+        chunk_->LookupConstant(LConstantOperand::cast(context));
+    __ LoadObject(cp, Handle<Object>::cast(constant->handle(isolate())));
   } else {
     UNREACHABLE();
   }