[turbofan] Fix more -Wsign-compare warnings.

test/cctest/compiler/test-run-wasm-machops.cc

 // Copyright 2016 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/utils/random-number-generator.h"
@@ skipping 33 matching lines @@
 static void RunLoadStoreRelocation(MachineType rep) {
   const int kNumElems = 2;
   CType buffer[kNumElems];
   CType new_buffer[kNumElems];
   byte* raw = reinterpret_cast<byte*>(buffer);
   byte* new_raw = reinterpret_cast<byte*>(new_buffer);
   for (size_t i = 0; i < sizeof(buffer); i++) {
     raw[i] = static_cast<byte>((i + sizeof(CType)) ^ 0xAA);
     new_raw[i] = static_cast<byte>((i + sizeof(CType)) ^ 0xAA);
   }
-  int32_t OK = 0x29000;
+  uint32_t OK = 0x29000;
   RawMachineAssemblerTester<uint32_t> m;
   Node* base = m.RelocatableIntPtrConstant(reinterpret_cast<intptr_t>(raw),
                                            RelocInfo::WASM_MEMORY_REFERENCE);
   Node* base1 = m.RelocatableIntPtrConstant(
       reinterpret_cast<intptr_t>(raw + sizeof(CType)),
       RelocInfo::WASM_MEMORY_REFERENCE);
   Node* index = m.Int32Constant(0);
   Node* load = m.Load(rep, base, index);
   m.Store(rep.representation(), base1, index, load, kNoWriteBarrier);
   m.Return(m.Int32Constant(OK));
@@ skipping 94 matching lines @@
   m.Bind(&out_of_bounds);
   m.Return(m.Int32Constant(0xdeadbeef));
   // Check that index is out of bounds with current size
   CHECK_EQ(0xdeadbeef, m.Call());
   m.GenerateCode();
 
   Handle<Code> code = m.GetCode();
   UpdateMemoryReferences(code, reinterpret_cast<Address>(1234),
                          reinterpret_cast<Address>(1234), 0x200, 0x400);
   // Check that after limit is increased, index is within bounds.
-  CHECK_EQ(0xaced, m.Call());
+  CHECK_EQ(0xacedu, m.Call());
 }