[wasm] Remove the module environment and signature as arguments to OpcodeArity.

R=rossberg@chromium.org,ahaas@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/1937083002
Cr-Commit-Position: refs/heads/master@{#35941}

src/wasm/ast-decoder.cc

@@ -287,21 +287,19 @@ class WasmDecoder : public Decoder {
 
       case kExprCallFunction: {
         CallFunctionOperand operand(this, pc);
-        return static_cast<int>(
-            module_->GetFunctionSignature(operand.index)->parameter_count());
+        return operand.arity;
       }
       case kExprCallIndirect: {
         CallIndirectOperand operand(this, pc);
-        return 1 + static_cast<int>(
-                       module_->GetSignature(operand.index)->parameter_count());
+        return 1 + operand.arity;
       }
       case kExprCallImport: {
         CallImportOperand operand(this, pc);
-        return static_cast<int>(
-            module_->GetImportSignature(operand.index)->parameter_count());
+        return operand.arity;
       }
       case kExprReturn: {
-        return static_cast<int>(sig_->return_count());
+        ReturnArityOperand operand(this, pc);
+        return operand.arity;
       }
 
 #define DECLARE_OPCODE_CASE(name, opcode, sig) \
@@ -1521,9 +1519,8 @@ int OpcodeLength(const byte* pc, const byte* end) {
   return decoder.OpcodeLength(pc);
 }
 
-int OpcodeArity(ModuleEnv* module, FunctionSig* sig, const byte* pc,
-                const byte* end) {
-  WasmDecoder decoder(module, sig, pc, end);
+int OpcodeArity(const byte* pc, const byte* end) {
+  WasmDecoder decoder(nullptr, nullptr, pc, end);
   return decoder.OpcodeArity(pc);
 }
 

src/wasm/ast-decoder.h

@@ -262,8 +262,8 @@ BitVector* AnalyzeLoopAssignmentForTesting(Zone* zone, size_t num_locals,
 int OpcodeLength(const byte* pc, const byte* end);
 
 // Computes the arity (number of sub-nodes) of the opcode at the given address.
-int OpcodeArity(ModuleEnv* module, FunctionSig* sig, const byte* pc,
-                const byte* end);
+int OpcodeArity(const byte* pc, const byte* end);
+
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8

test/unittests/wasm/ast-decoder-unittest.cc

@@ -2049,18 +2049,15 @@ TEST_F(WasmOpcodeLengthTest, SimpleExpressions) {
 class WasmOpcodeArityTest : public TestWithZone {
  public:
   WasmOpcodeArityTest() : TestWithZone() {}
-  TestModuleEnv module;
-  TestSignatures sigs;
 };
 
 #define EXPECT_ARITY(expected, ...)                              \
   {                                                              \
     static const byte code[] = {__VA_ARGS__};                    \
-    EXPECT_EQ(expected, OpcodeArity(&module, sig, code, code + sizeof(code))); \
+    EXPECT_EQ(expected, OpcodeArity(code, code + sizeof(code))); \
   }
 
 TEST_F(WasmOpcodeArityTest, Control) {
-  FunctionSig* sig = sigs.v_v();
   EXPECT_ARITY(0, kExprNop);
 
   EXPECT_ARITY(0, kExprBlock, 0);
@@ -2086,16 +2083,13 @@ TEST_F(WasmOpcodeArityTest, Control) {
   EXPECT_ARITY(2, kExprBrTable, ARITY_1);
 
   {
-    sig = sigs.v_v();
     EXPECT_ARITY(0, kExprReturn, ARITY_0);
-    sig = sigs.i_i();
     EXPECT_ARITY(1, kExprReturn, ARITY_1);
   }
 }
 
 
 TEST_F(WasmOpcodeArityTest, Misc) {
-  FunctionSig* sig = sigs.v_v();
   EXPECT_ARITY(0, kExprI8Const);
   EXPECT_ARITY(0, kExprI32Const);
   EXPECT_ARITY(0, kExprF32Const);
@@ -2109,18 +2103,7 @@ TEST_F(WasmOpcodeArityTest, Misc) {
 
 
 TEST_F(WasmOpcodeArityTest, Calls) {
-  module.AddFunction(sigs.i_ii());
-  module.AddFunction(sigs.i_i());
-
-  module.AddSignature(sigs.f_ff());
-  module.AddSignature(sigs.i_d());
-
-  module.AddImport(sigs.f_ff());
-  module.AddImport(sigs.i_d());
-
   {
-    FunctionSig* sig = sigs.i_ii();
-
     EXPECT_ARITY(2, kExprCallFunction, 2, 0);
     EXPECT_ARITY(2, kExprCallImport, 2, 0);
     EXPECT_ARITY(3, kExprCallIndirect, 2, 0);
@@ -2135,8 +2118,6 @@ TEST_F(WasmOpcodeArityTest, Calls) {
   }
 
   {
-    FunctionSig* sig = sigs.v_v();
-
     EXPECT_ARITY(1, kExprCallFunction, ARITY_1, 1);
     EXPECT_ARITY(1, kExprCallImport, ARITY_1, 1);
     EXPECT_ARITY(2, kExprCallIndirect, ARITY_1, 1);
@@ -2153,7 +2134,6 @@ TEST_F(WasmOpcodeArityTest, Calls) {
 
 
 TEST_F(WasmOpcodeArityTest, LoadsAndStores) {
-  FunctionSig* sig = sigs.v_v();
   EXPECT_ARITY(1, kExprI32LoadMem8S);
   EXPECT_ARITY(1, kExprI32LoadMem8U);
   EXPECT_ARITY(1, kExprI32LoadMem16S);
@@ -2183,14 +2163,12 @@ TEST_F(WasmOpcodeArityTest, LoadsAndStores) {
 
 
 TEST_F(WasmOpcodeArityTest, MiscMemExpressions) {
-  FunctionSig* sig = sigs.v_v();
   EXPECT_ARITY(0, kExprMemorySize);
   EXPECT_ARITY(1, kExprGrowMemory);
 }
 
 
 TEST_F(WasmOpcodeArityTest, SimpleExpressions) {
-  FunctionSig* sig = sigs.v_v();
   EXPECT_ARITY(2, kExprI32Add);
   EXPECT_ARITY(2, kExprI32Sub);
   EXPECT_ARITY(2, kExprI32Mul);