Revert of [ic] [stubs] Don't use Code::flags in megamorphic stub cache hash computations.

src/ic/x87/stub-cache-x87.cc

Index: src/ic/x87/stub-cache-x87.cc
diff --git a/src/ic/x87/stub-cache-x87.cc b/src/ic/x87/stub-cache-x87.cc
index fba0c8e4d694193ab9e582c32bf744bcbccdf3e2..ef2246fc09e84899dba76d51a50bf213c79105e7 100644
--- a/src/ic/x87/stub-cache-x87.cc
+++ b/src/ic/x87/stub-cache-x87.cc
@@ -15,6 +15,7 @@
 #define __ ACCESS_MASM(masm)
 
 static void ProbeTable(StubCache* stub_cache, MacroAssembler* masm,
+                       Code::Kind ic_kind, Code::Flags flags,
                        StubCache::Table table, Register name, Register receiver,
                        // Number of the cache entry pointer-size scaled.
                        Register offset, Register extra) {
@@ -25,7 +26,6 @@
       ExternalReference::virtual_handler_register(masm->isolate());
 
   Label miss;
-  Code::Kind ic_kind = stub_cache->ic_kind();
   bool is_vector_store =
       IC::ICUseVector(ic_kind) &&
       (ic_kind == Code::STORE_IC || ic_kind == Code::KEYED_STORE_IC);
@@ -46,15 +46,13 @@
     __ cmp(offset, FieldOperand(receiver, HeapObject::kMapOffset));
     __ j(not_equal, &miss);
 
-#ifdef DEBUG
     // Check that the flags match what we're looking for.
-    Code::Flags flags = Code::RemoveHolderFromFlags(
-        Code::ComputeHandlerFlags(stub_cache->ic_kind()));
     __ mov(offset, FieldOperand(extra, Code::kFlagsOffset));
     __ and_(offset, ~Code::kFlagsNotUsedInLookup);
     __ cmp(offset, flags);
-    __ Check(equal, kUnexpectedValue);
-
+    __ j(not_equal, &miss);
+
+#ifdef DEBUG
     if (FLAG_test_secondary_stub_cache && table == StubCache::kPrimary) {
       __ jmp(&miss);
     } else if (FLAG_test_primary_stub_cache && table == StubCache::kSecondary) {
@@ -103,15 +101,13 @@
     // Get the code entry from the cache.
     __ mov(offset, Operand::StaticArray(offset, times_1, value_offset));
 
-#ifdef DEBUG
     // Check that the flags match what we're looking for.
-    Code::Flags flags = Code::RemoveHolderFromFlags(
-        Code::ComputeHandlerFlags(stub_cache->ic_kind()));
     __ mov(offset, FieldOperand(offset, Code::kFlagsOffset));
     __ and_(offset, ~Code::kFlagsNotUsedInLookup);
     __ cmp(offset, flags);
-    __ Check(equal, kUnexpectedValue);
-
+    __ j(not_equal, &miss);
+
+#ifdef DEBUG
     if (FLAG_test_secondary_stub_cache && table == StubCache::kPrimary) {
       __ jmp(&miss);
     } else if (FLAG_test_primary_stub_cache && table == StubCache::kSecondary) {
@@ -148,6 +144,9 @@
 void StubCache::GenerateProbe(MacroAssembler* masm, Register receiver,
                               Register name, Register scratch, Register extra,
                               Register extra2, Register extra3) {
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(ic_kind_));
+
   Label miss;
 
   // Assert that code is valid.  The multiplying code relies on the entry size
@@ -178,6 +177,7 @@
   // Get the map of the receiver and compute the hash.
   __ mov(offset, FieldOperand(name, Name::kHashFieldOffset));
   __ add(offset, FieldOperand(receiver, HeapObject::kMapOffset));
+  __ xor_(offset, flags);
   // We mask out the last two bits because they are not part of the hash and
   // they are always 01 for maps.  Also in the two 'and' instructions below.
   __ and_(offset, (kPrimaryTableSize - 1) << kCacheIndexShift);
@@ -186,17 +186,21 @@
   DCHECK(kCacheIndexShift == kPointerSizeLog2);
 
   // Probe the primary table.
-  ProbeTable(this, masm, kPrimary, name, receiver, offset, extra);
+  ProbeTable(this, masm, ic_kind_, flags, kPrimary, name, receiver, offset,
+             extra);
 
   // Primary miss: Compute hash for secondary probe.
   __ mov(offset, FieldOperand(name, Name::kHashFieldOffset));
   __ add(offset, FieldOperand(receiver, HeapObject::kMapOffset));
+  __ xor_(offset, flags);
   __ and_(offset, (kPrimaryTableSize - 1) << kCacheIndexShift);
   __ sub(offset, name);
+  __ add(offset, Immediate(flags));
   __ and_(offset, (kSecondaryTableSize - 1) << kCacheIndexShift);
 
   // Probe the secondary table.
-  ProbeTable(this, masm, kSecondary, name, receiver, offset, extra);
+  ProbeTable(this, masm, ic_kind_, flags, kSecondary, name, receiver, offset,
+             extra);
 
   // Cache miss: Fall-through and let caller handle the miss by
   // entering the runtime system.