[turbofan] Refactor the InstructionSelector tests.

src/compiler/arm/instruction-selector-arm.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/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler-intrinsics.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 123 matching lines @@
     std::swap(shl, shr);
   } else if (!m.left().IsWord32Shl() || !m.right().IsWord32Shr()) {
     return false;
   }
   Int32BinopMatcher mshr(shr);
   Int32BinopMatcher mshl(shl);
   Node* value = mshr.left().node();
   if (value != mshl.left().node()) return false;
   Node* shift = mshr.right().node();
   Int32Matcher mshift(shift);
-  if (mshift.IsInRange(1, 31) && mshl.right().Is(32 - mshift.Value())) {
-    *opcode_return |= AddressingModeField::encode(kMode_Operand2_R_ROR_I);
-    *value_return = g.UseRegister(value);
-    *shift_return = g.UseImmediate(shift);
-    return true;
+  if (mshift.IsInRange(1, 31)) {
+    if (mshl.right().Is(32 - mshift.Value())) {
+      *opcode_return |= AddressingModeField::encode(kMode_Operand2_R_ROR_I);
+      *value_return = g.UseRegister(value);
+      *shift_return = g.UseImmediate(shift);
+      return true;
+    }
+    if (mshl.right().IsInt32Sub()) {
+      Int32BinopMatcher mshlright(mshl.right().node());
+      if (mshlright.left().Is(32) && mshlright.right().Is(mshift.Value())) {
+        *opcode_return |= AddressingModeField::encode(kMode_Operand2_R_ROR_I);
+        *value_return = g.UseRegister(value);
+        *shift_return = g.UseImmediate(shift);
+        return true;
+      }
+    }
   }
   if (mshl.right().IsInt32Sub()) {
     Int32BinopMatcher mshlright(mshl.right().node());
     if (!mshlright.left().Is(32)) return false;
     if (mshlright.right().node() != shift) return false;
     *opcode_return |= AddressingModeField::encode(kMode_Operand2_R_ROR_R);
     *value_return = g.UseRegister(value);
     *shift_return = g.UseRegister(shift);
     return true;
   }
@@ skipping 775 matching lines @@
     DCHECK(cont->IsSet());
     Emit(cont->Encode(kArmVcmpF64), g.DefineAsRegister(cont->result()),
          g.UseDoubleRegister(m.left().node()),
          g.UseDoubleRegister(m.right().node()));
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8