[wasm] Fix misaligned accesses and endianness issues in decoders.

test/cctest/wasm/test-run-wasm.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 <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "src/wasm/wasm-macro-gen.h"
 
@@ skipping 2360 matching lines @@
   // Build the calling function.
   WasmRunner<int32_t> r;
   r.env()->module = &module;
   BUILD(r, WASM_CALL_FUNCTION0(index));
 
   int32_t result = r.Call();
   CHECK_EQ(kExpected, result);
 }
 
 
-// TODO(tizer): Fix on arm and reenable.
-#if !V8_TARGET_ARCH_ARM && !V8_TARGET_ARCH_ARM64
-
 TEST(Run_WasmCallF32StackParameter) {
   // Build the target function.
   LocalType param_types[20];
   for (int i = 0; i < 20; i++) param_types[i] = kAstF32;
   FunctionSig sig(1, 19, param_types);
   TestingModule module;
   WasmFunctionCompiler t(&sig);
   BUILD(t, WASM_GET_LOCAL(17));
   uint32_t index = t.CompileAndAdd(&module);
 
@@ skipping 31 matching lines @@
                               WASM_F64(32.0), WASM_F64(64.0), WASM_F64(128.0),
                               WASM_F64(256.0), WASM_F64(1.5), WASM_F64(2.5),
                               WASM_F64(4.5), WASM_F64(8.5), WASM_F64(16.5),
                               WASM_F64(32.5), WASM_F64(64.5), WASM_F64(128.5),
                               WASM_F64(256.5), WASM_F64(512.5)));
 
   float result = r.Call();
   CHECK_EQ(256.5, result);
 }
 
-#endif
-
 
 TEST(Run_WasmCallVoid) {
   const byte kMemOffset = 8;
   const int32_t kElemNum = kMemOffset / sizeof(int32_t);
   const int32_t kExpected = -414444;
   // Build the target function.
   TestSignatures sigs;
   TestingModule module;
   module.AddMemory(16);
   module.RandomizeMemory();
@@ skipping 873 matching lines @@
 
 #if WASM_64
 TEST(Compile_Wasm_CallIndirect_Many_i64) { CompileCallIndirectMany(kAstI64); }
 #endif
 
 
 TEST(Compile_Wasm_CallIndirect_Many_f32) { CompileCallIndirectMany(kAstF32); }
 
 
 TEST(Compile_Wasm_CallIndirect_Many_f64) { CompileCallIndirectMany(kAstF64); }