Adding assertions to fast elements conversion.

Review URL: http://codereview.chromium.org/8437092

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9875 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/codegen-arm.cc

@@ -180,6 +180,10 @@ void ElementsTransitionGenerator::GenerateSmiOnlyToDouble(
 
   // Hole found, store the-hole NaN.
   __ bind(&convert_hole);
+  if (FLAG_debug_code) {
+    __ CompareRoot(r9, Heap::kTheHoleValueRootIndex);
+    __ Assert(eq, "object found in smi-only array");
+  }
   __ Strd(r4, r5, MemOperand(r7, 8, PostIndex));
 
   __ bind(&entry);

src/ia32/codegen-ia32.cc

@@ -378,6 +378,12 @@ void ElementsTransitionGenerator::GenerateSmiOnlyToDouble(
 
   // Found hole, store hole_nan_as_double instead.
   __ bind(&convert_hole);
+
+  if (FLAG_debug_code) {
+    __ cmp(ebx, masm->isolate()->factory()->the_hole_value());
+    __ Assert(equal, "object found in smi-only array");
+  }
+
   if (CpuFeatures::IsSupported(SSE2)) {
     CpuFeatures::Scope use_sse2(SSE2);
     __ movdbl(FieldOperand(eax, edi, times_4, FixedDoubleArray::kHeaderSize),

src/x64/codegen-x64.cc

@@ -254,6 +254,12 @@ void ElementsTransitionGenerator::GenerateSmiOnlyToDouble(
            xmm0);
   __ jmp(&entry);
   __ bind(&convert_hole);
+
+  if (FLAG_debug_code) {
+    __ CompareRoot(rbx, Heap::kTheHoleValueRootIndex);
+    __ Assert(equal, "object found in smi-only array");
+  }
+
   __ movq(FieldOperand(r14, r9, times_8, FixedDoubleArray::kHeaderSize), r15);
   __ bind(&entry);
   __ decq(r9);