Improve code generation for bounds checks.

src/ia32/lithium-codegen-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4479 matching lines @@
   ASSERT(ToRegister(instr->context()).is(esi));
   ASSERT(ToRegister(instr->object()).is(edx));
   ASSERT(ToRegister(instr->value()).is(eax));
 
   __ mov(ecx, instr->name());
   Handle<Code> ic = StoreIC::initialize_stub(isolate(), instr->strict_mode());
   CallCode(ic, RelocInfo::CODE_TARGET, instr);
 }
 
 
-void LCodeGen::ApplyCheckIf(Condition cc, LBoundsCheck* check) {
-  if (FLAG_debug_code && check->hydrogen()->skip_check()) {
+void LCodeGen::DoBoundsCheck(LBoundsCheck* instr) {
+  Condition cc = instr->hydrogen()->allow_equality() ? above : above_equal;
+  if (instr->index()->IsConstantOperand()) {
+    __ cmp(ToOperand(instr->length()),
+           ToImmediate(LConstantOperand::cast(instr->index()),
+                       instr->hydrogen()->length()->representation()));
+    cc = ReverseCondition(cc);
+  } else if (instr->length()->IsConstantOperand()) {
+    __ cmp(ToOperand(instr->index()),
+           ToImmediate(LConstantOperand::cast(instr->length()),
+                       instr->hydrogen()->index()->representation()));
+  } else {
+    __ cmp(ToRegister(instr->index()), ToOperand(instr->length()));
+  }
+  if (FLAG_debug_code && instr->hydrogen()->skip_check()) {
     Label done;
     __ j(NegateCondition(cc), &done, Label::kNear);
     __ int3();
     __ bind(&done);
   } else {
-    DeoptimizeIf(cc, check->environment());
+    DeoptimizeIf(cc, instr->environment());
   }
 }
 
-
-void LCodeGen::DoBoundsCheck(LBoundsCheck* instr) {
-  if (instr->hydrogen()->skip_check() && !FLAG_debug_code) return;
-
-  if (instr->index()->IsConstantOperand()) {
-    Immediate immediate =
-        ToImmediate(LConstantOperand::cast(instr->index()),
-                    instr->hydrogen()->length()->representation());
-    __ cmp(ToOperand(instr->length()), immediate);
-    Condition condition =
-        instr->hydrogen()->allow_equality() ? below : below_equal;
-    ApplyCheckIf(condition, instr);
-  } else {
-    __ cmp(ToRegister(instr->index()), ToOperand(instr->length()));
-    Condition condition =
-        instr->hydrogen()->allow_equality() ? above : above_equal;
-    ApplyCheckIf(condition, instr);
-  }
-}
-
 
 void LCodeGen::DoStoreKeyedExternalArray(LStoreKeyed* instr) {
   ElementsKind elements_kind = instr->elements_kind();
   LOperand* key = instr->key();
   if (!key->IsConstantOperand() &&
       ExternalArrayOpRequiresTemp(instr->hydrogen()->key()->representation(),
                                   elements_kind)) {
     __ SmiUntag(ToRegister(key));
   }
   Operand operand(BuildFastArrayOperand(
@@ skipping 1908 matching lines @@
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32