MIPS: Check that index and length are Smi in bounds check.

Port r12362 (cd39337c)

BUG=
TEST=

Review URL: https://chromiumcodereview.appspot.com/10876053
Patch from Akos Palfi <palfia@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12376 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/lithium-codegen-mips.cc

@@ -3660,7 +3660,29 @@ void LCodeGen::DoStoreNamedGeneric(LStoreNamedGeneric* instr) {
 }
 
 
+void LCodeGen::DeoptIfTaggedButNotSmi(LEnvironment* environment,
+                                      HValue* value,
+                                      LOperand* operand) {
+  if (value->representation().IsTagged() && !value->type().IsSmi()) {
+    if (operand->IsRegister()) {
+      __ And(at, ToRegister(operand), Operand(kSmiTagMask));
+      DeoptimizeIf(ne, environment, at, Operand(zero_reg));
+    } else {
+      __ li(at, ToOperand(operand));
+      __ And(at, at, Operand(kSmiTagMask));
+      DeoptimizeIf(ne, environment, at, Operand(zero_reg));
+    }
+  }
+}
+
+
 void LCodeGen::DoBoundsCheck(LBoundsCheck* instr) {
+  DeoptIfTaggedButNotSmi(instr->environment(),
+                         instr->hydrogen()->length(),
+                         instr->length());
+  DeoptIfTaggedButNotSmi(instr->environment(),
+                         instr->hydrogen()->index(),
+                         instr->index());
   if (instr->index()->IsConstantOperand()) {
     int constant_index =
         ToInteger32(LConstantOperand::cast(instr->index()));

src/mips/lithium-codegen-mips.h

@@ -307,6 +307,10 @@ class LCodeGen BASE_EMBEDDED {
                         bool deoptimize_on_minus_zero,
                         LEnvironment* env);
 
+  void DeoptIfTaggedButNotSmi(LEnvironment* environment,
+                              HValue* value,
+                              LOperand* operand);
+
   // Emits optimized code for typeof x == "y".  Modifies input register.
   // Returns the condition on which a final split to
   // true and false label should be made, to optimize fallthrough.