Fix -Wsign-compare warnings in parser, scanner, regexp, runtime.

test/unittests/source-position-table-unittest.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 "src/v8.h"
 
 #include "src/objects.h"
 #include "src/source-position-table.h"
 #include "test/unittests/test-utils.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 class SourcePositionTableTest : public TestWithIsolateAndZone {
  public:
   SourcePositionTableTest() {}
   ~SourcePositionTableTest() override {}
 };
 
 // Some random offsets, mostly at 'suspicious' bit boundaries.
 static int offsets[] = {0,   1,   2,    3,    4,     30,      31,  32,
                         33,  62,  63,   64,   65,    126,     127, 128,
                         129, 250, 1000, 9999, 12000, 31415926};
 
 TEST_F(SourcePositionTableTest, EncodeStatement) {
   SourcePositionTableBuilder builder(zone());
-  for (int i = 0; i < arraysize(offsets); i++) {
+  for (size_t i = 0; i < arraysize(offsets); i++) {
     builder.AddPosition(offsets[i], offsets[i], true);
   }
 
   // To test correctness, we rely on the assertions in ToSourcePositionTable().
   // (Also below.)
   CHECK(!builder.ToSourcePositionTable(isolate(), Handle<AbstractCode>())
              .is_null());
 }
 
 TEST_F(SourcePositionTableTest, EncodeStatementDuplicates) {
   SourcePositionTableBuilder builder(zone());
-  for (int i = 0; i < arraysize(offsets); i++) {
+  for (size_t i = 0; i < arraysize(offsets); i++) {
     builder.AddPosition(offsets[i], offsets[i], true);
     builder.AddPosition(offsets[i], offsets[i] + 1, true);
   }
 
   // To test correctness, we rely on the assertions in ToSourcePositionTable().
   // (Also below.)
   CHECK(!builder.ToSourcePositionTable(isolate(), Handle<AbstractCode>())
              .is_null());
 }
 
 TEST_F(SourcePositionTableTest, EncodeExpression) {
   SourcePositionTableBuilder builder(zone());
-  for (int i = 0; i < arraysize(offsets); i++) {
+  for (size_t i = 0; i < arraysize(offsets); i++) {
     builder.AddPosition(offsets[i], offsets[i], false);
   }
   CHECK(!builder.ToSourcePositionTable(isolate(), Handle<AbstractCode>())
              .is_null());
 }
 
 TEST_F(SourcePositionTableTest, EncodeAscending) {
   SourcePositionTableBuilder builder(zone());
 
   int code_offset = 0;
   int source_position = 0;
-  for (int i = 0; i < arraysize(offsets); i++) {
+  for (size_t i = 0; i < arraysize(offsets); i++) {
     code_offset += offsets[i];
     source_position += offsets[i];
     if (i % 2) {
       builder.AddPosition(code_offset, source_position, true);
     } else {
       builder.AddPosition(code_offset, source_position, false);
     }
   }
 
   // Also test negative offsets for source positions:
-  for (int i = 0; i < arraysize(offsets); i++) {
+  for (size_t i = 0; i < arraysize(offsets); i++) {
     code_offset += offsets[i];
     source_position -= offsets[i];
     if (i % 2) {
       builder.AddPosition(code_offset, source_position, true);
     } else {
       builder.AddPosition(code_offset, source_position, false);
     }
   }
 
   CHECK(!builder.ToSourcePositionTable(isolate(), Handle<AbstractCode>())
              .is_null());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8