1 files changed, 121 insertions, 0 deletions
diff --git a/deps/v8/test/unittests/wasm/wasm-text-unittest.cc b/deps/v8/test/unittests/wasm/wasm-text-unittest.cc
new file mode 100644
index 0000000000..e960b730a5
--- /dev/null
+++ b/deps/v8/test/unittests/wasm/wasm-text-unittest.cc
@@ -0,0 +1,121 @@
+// Copyright 2019 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 <sstream>
+
+#include "test/unittests/test-utils.h"
+
+#include "src/wasm/module-decoder.h"
+#include "src/wasm/wasm-module-builder.h"
+#include "src/wasm/wasm-module.h"
+#include "src/wasm/wasm-opcodes.h"
+#include "src/wasm/wasm-text.h"
+#include "test/common/wasm/test-signatures.h"
+
+namespace v8 {
+namespace internal {
+namespace wasm {
+
+class WasmTextTest : public TestWithIsolateAndZone {
+ public:
+  TestSignatures sigs;
+  WasmFeatures enabled_features_;
+
+  void TestInstruction(const byte* func_start, size_t func_size) {
+    WasmModuleBuilder mb(zone());
+    auto* fb = mb.AddFunction(sigs.v_v());
+    fb->EmitCode(func_start, static_cast<uint32_t>(func_size));
+    fb->Emit(kExprEnd);
+
+    ZoneBuffer buffer(zone());
+    mb.WriteTo(&buffer);
+
+    ModuleWireBytes wire_bytes(
+        Vector<const byte>(buffer.begin(), buffer.size()));
+
+    ModuleResult result = DecodeWasmModule(
+        enabled_features_, buffer.begin(), buffer.end(), false, kWasmOrigin,
+        isolate()->counters(), isolate()->wasm_engine()->allocator());
+    EXPECT_TRUE(result.ok());
+
+    std::stringstream ss;
+    PrintWasmText(result.value().get(), wire_bytes, 0, ss, nullptr);
+  }
+};
+
+TEST_F(WasmTextTest, EveryOpcodeCanBeDecoded) {
+  static const struct {
+    WasmOpcode opcode;
+    const char* debug_name;
+  } kValues[] = {
+#define DECLARE_ELEMENT(name, opcode, sig) {kExpr##name, "kExpr" #name},
+      FOREACH_OPCODE(DECLARE_ELEMENT)};
+#undef DECLARE_ELEMENT
+
+  for (const auto& value : kValues) {
+    // Pad with 0 for any immediate values. If they're not needed, they'll be
+    // interpreted as unreachable.
+    byte data[20] = {0};
+
+    printf("%s\n", value.debug_name);
+    switch (value.opcode) {
+      // Instructions that have a special case because they affect the control
+      // depth.
+      case kExprBlock:
+      case kExprLoop:
+      case kExprIf:
+      case kExprTry:
+        data[0] = value.opcode;
+        data[1] = kLocalVoid;
+        data[2] = kExprEnd;
+        break;
+      case kExprElse:
+        data[0] = kExprIf;
+        data[1] = value.opcode;
+        data[2] = kExprEnd;
+        break;
+      case kExprCatch:
+        data[0] = kExprTry;
+        data[1] = value.opcode;
+        data[2] = kExprEnd;
+        break;
+      case kExprEnd:
+        break;
+
+      // Instructions with special requirements for immediates.
+      case kExprSelectWithType:
+        data[0] = kExprSelectWithType;
+        data[1] = 1;
+        data[2] = kLocalI32;
+        break;
+
+      default: {
+        if (value.opcode >= 0x100) {
+          data[0] = value.opcode >> 8;        // Prefix byte.
+          byte opcode = value.opcode & 0xff;  // Actual opcode.
+          if (opcode >= 0x80) {
+            // Opcode with prefix, and needs to be LEB encoded (3 bytes).
+            // For now, this can only be in the range [0x80, 0xff], which means
+            // that the third byte is always 1.
+            data[1] = (opcode & 0x7f) | 0x80;
+            data[2] = 1;
+          } else {
+            // Opcode with prefix (2 bytes).
+            data[1] = opcode;
+          }
+        } else {
+          // Single-byte opcode.
+          data[0] = value.opcode;
+        }
+        break;
+      }
+    }
+
+    TestInstruction(data, arraysize(data));
+  }
+}
+
+}  // namespace wasm
+}  // namespace internal
+}  // namespace v8