[turbofan] Reland of `Add alignment parameter to StackSlot operator`

test/cctest/compiler/test-run-machops.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 <cmath>
 #include <functional>
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/base/ieee754.h"
@@ skipping 6721 matching lines @@
   r.Goto(&merge);
   r.Bind(&flabel);
   Node* fb = r.Int32Constant(0);
   r.Goto(&merge);
   r.Bind(&merge);
   Node* phi = r.Phi(MachineRepresentation::kWord32, fa, fb);
   r.Return(phi);
   CHECK_EQ(1, r.Call(1));
 }
 
+#if V8_HOST_ARCH_MIPS || V8_HOST_ARCH_MIPS64
+
+TEST(StackSlotAlignment) {
+  RawMachineAssemblerTester<int32_t> r;
+  RawMachineLabel tlabel;
+  RawMachineLabel flabel;
+  RawMachineLabel merge;
+
+  int alignments[] = {4, 8, 16};
+  int alignment_count = arraysize(alignments);
+
+  Node* alignment_counter = r.Int32Constant(0);
+  for (int i = 0; i < alignment_count; i++) {
+    for (int j = 0; j < 5; j++) {
+      Node* stack_slot =
+          r.StackSlot(MachineRepresentation::kWord32, alignments[i]);
+      alignment_counter = r.Int32Add(
+          alignment_counter,
+          r.Word32And(stack_slot, r.Int32Constant(alignments[i] - 1)));
+    }
+  }
+
+  r.Return(alignment_counter);
+  CHECK_EQ(0, r.Call(1));
+}
+
+#endif  // V8_HOST_ARCH_MIPS || V8_HOST_ARCH_MIPS64
+
 #if V8_TARGET_ARCH_64_BIT
 
 TEST(Regression5923) {
   {
     BufferedRawMachineAssemblerTester<int64_t> m(MachineType::Int64());
     m.Return(m.Int64Add(
         m.Word64Shr(m.Parameter(0), m.Int64Constant(4611686018427387888)),
         m.Parameter(0)));
     int64_t input = 16;
     m.Call(input);
@@ skipping 59 matching lines @@
   BufferedRawMachineAssemblerTester<int32_t> m(MachineType::Int32());
   m.Return(m.Word32And(m.Word32Shr(m.Parameter(0), m.Int32Constant(0)),
                        m.Int32Constant(0xffffffff)));
   int32_t input = 1234;
   CHECK_EQ(input, m.Call(input));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8