[Interpreter] Basic flow control.

test/cctest/interpreter/test-bytecode-generator.cc

 // Copyright 2015 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/compiler.h"
 #include "src/interpreter/bytecode-generator.h"
 #include "src/interpreter/interpreter.h"
 #include "test/cctest/cctest.h"
@@ skipping 590 matching lines @@
                   ba->length()));
     CHECK_EQ(ba->constant_pool()->length(), snippets[i].constant_count);
     for (int j = 0; j < snippets[i].constant_count; j++) {
       Handle<String> expected =
           helper.factory()->NewStringFromAsciiChecked(snippets[i].constants[j]);
       CHECK(String::cast(ba->constant_pool()->get(j))->Equals(*expected));
     }
   }
 }
 
+
+TEST(IfConditions) {
+  InitializedHandleScope handle_scope;
+  BytecodeGeneratorHelper helper;
+
+  ExpectedSnippet<void*> snippets[] = {{
+      "function f(arg1) { if (false) { return 1; } else { return -1; } }",

[rmcilroy, 2015/09/18 10:42:24]

nit - remove arg1

[oth, 2015/09/23 10:46:56]

Done.

+      0,
+      2,
+      11,
+      {
+        B(LdaFalse),
+        B(JumpIfFalseSmi8), U8(7),
+        B(LdaSmi8), U8(1),
+        B(Return),
+        B(JumpSmi8), U8(5),  // TODO(oth): Fix implicit return so dead-jump has
+                             // a valid target.
+        B(LdaSmi8), U8(-1),
+        B(Return)
+      }},
+      {
+      "function f(a) { if (a <= 0) { return 200; } else { return -200; } }",
+      kPointerSize,
+      2,
+      17,
+      {
+        B(Ldar), R(-5),
+        B(Star), R(0),
+        B(LdaZero),
+        B(TestLessThanEqual), R(0),
+        B(JumpIfFalseSmi8), U8(7),
+        B(LdaConstant), U8(0),
+        B(Return),
+        B(JumpSmi8), U8(5),  // TODO(oth): Fix implicit return so dead-jump has
+                             // a valid target.
+        B(LdaConstant), U8(1),
+        B(Return)
+      }},

[rmcilroy, 2015/09/18 10:42:24]

could you add some tests for:
 - non-bool values (e.g., if (arg1)...
 - a couple of other comparison operations (e.g., ===, instanceof, in, etc.)
 - code which would require a constant pool jump (e.g., >128 bytecode range)
(you could do this as a separate test which doesn't require you to write out 128
bytecodes to check in the snippet, but maybe you only check the prefix of the
resulting bytecode)
 

[oth, 2015/09/23 10:46:56]

Done. There will be more tests to follow as well in the test operator
implementation CL.

+  };
+
+  size_t num_snippets = sizeof(snippets) / sizeof(snippets[0]);
+  for (size_t i = 0; i < num_snippets; i++) {
+    Handle<BytecodeArray> ba =
+        helper.MakeBytecodeForFunction(snippets[i].code_snippet);
+    ba->Print();
+    CHECK_EQ(ba->frame_size(), snippets[i].frame_size);
+    CHECK_EQ(ba->parameter_count(), snippets[i].parameter_count);
+    CHECK_EQ(ba->length(), snippets[i].bytecode_length);
+    CHECK(!memcmp(ba->GetFirstBytecodeAddress(), snippets[i].bytecode,
+                  ba->length()));
+  }
+}
+
+
 }  // namespace interpreter
 }  // namespace internal
 }  // namespance v8