Bug 937697 - Simplify some BoundsCheckRange code. r=bhackett

--HG--
extra : rebase_source : 719258647e87d0bf52636e5d23085e2f1f7e2ec5

js/src/jit/CodeGenerator.cpp

@@ -5013,16 +5013,19 @@ CodeGenerator::visitBoundsCheckRange(LBoundsCheckRange *lir)
             masm.add32(Imm32(min), temp);
             if (!bailoutIf(Assembler::Overflow, lir->snapshot()))
                 return false;
+        }
+
+        masm.cmp32(temp, Imm32(0));
+        if (!bailoutIf(Assembler::LessThan, lir->snapshot()))
+            return false;
+
+        if (min != 0) {
             int32_t diff;
             if (SafeSub(max, min, &diff))
                 max = diff;
             else
                 masm.sub32(Imm32(min), temp);
         }
-
-        masm.cmp32(temp, Imm32(0));
-        if (!bailoutIf(Assembler::LessThan, lir->snapshot()))
-            return false;
     }
 
     // Compute the maximum possible index. No overflow check is needed when