PPC/s390: Check for overflow when SubI IntMin

src/crankshaft/s390/lithium-codegen-s390.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 //
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/crankshaft/s390/lithium-codegen-s390.h"
 
 #include "src/base/bits.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-factory.h"
@@ skipping 1664 matching lines @@
 #if V8_TARGET_ARCH_S390X
   // The overflow detection needs to be tested on the lower 32-bits.
   // As a result, on 64-bit, we need to force 32-bit arithmetic operations
   // to set the CC overflow bit properly.  The result is then sign-extended.
   bool checkOverflow = instr->hydrogen()->CheckFlag(HValue::kCanOverflow);
 #else
   bool checkOverflow = true;
 #endif
 
   if (right->IsConstantOperand()) {
-    if (!isInteger || !checkOverflow)
+    if (!isInteger || !checkOverflow) {
       __ SubP(ToRegister(result), ToRegister(left), ToOperand(right));
-    else
-      __ Sub32(ToRegister(result), ToRegister(left), ToOperand(right));
+    } else {
+      // -(MinInt) will overflow
+      if (ToInteger32(LConstantOperand::cast(right)) == kMinInt) {
+        __ Load(scratch0(), ToOperand(right));
+        __ Sub32(ToRegister(result), ToRegister(left), scratch0());
+      } else {
+        __ Sub32(ToRegister(result), ToRegister(left), ToOperand(right));
+      }
+    }
   } else if (right->IsRegister()) {
     if (!isInteger)
       __ SubP(ToRegister(result), ToRegister(left), ToRegister(right));
     else if (!checkOverflow)
       __ SubP_ExtendSrc(ToRegister(result), ToRegister(left),
                         ToRegister(right));
     else
       __ Sub32(ToRegister(result), ToRegister(left), ToRegister(right));
   } else {
     if (!left->Equals(instr->result()))
@@ skipping 3854 matching lines @@
   __ LoadP(result,
            FieldMemOperand(scratch, FixedArray::kHeaderSize - kPointerSize));
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8