[base] Simplify and extend VectorOf method

And use it in several places in wasm.

R=tebbi@chromium.org

Bug: v8:8562
Change-Id: I1e857baf33e99849eb32ac2c94e39d7f27b180c8
Reviewed-on: https://chromium-review.googlesource.com/c/1391757
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58495}

src/vector.h

@@ -10,6 +10,7 @@
 #include <iterator>
 
 #include "src/allocation.h"
+#include "src/base/macros.h"
 #include "src/checks.h"
 #include "src/globals.h"
 
@@ -257,10 +258,10 @@ inline int StrLength(const char* string) {
   return static_cast<int>(length);
 }
 
-
-#define STATIC_CHAR_VECTOR(x)                                              \
-  v8::internal::Vector<const uint8_t>(reinterpret_cast<const uint8_t*>(x), \
-                                      arraysize(x) - 1)
+#define STATIC_CHAR_VECTOR(x)                                          \
+  v8::internal::VectorOf(                                              \
+      reinterpret_cast<const uint8_t*>(implicit_cast<const char*>(x)), \
+      arraysize(x) - 1)
 
 inline Vector<const char> CStrVector(const char* data) {
   return Vector<const char>(data, StrLength(data));
@@ -288,13 +289,17 @@ inline constexpr Vector<T> ArrayVector(T (&arr)[N]) {
   return Vector<T>(arr);
 }
 
+// Construct a Vector from a start pointer and a size.
+template <typename T>
+inline constexpr Vector<T> VectorOf(T* start, size_t size) {
+  return Vector<T>(start, size);
+}
+
 // Construct a Vector from anything providing a {data()} and {size()} accessor.
-template <typename Container,
-          typename T = typename std::remove_reference<
-              decltype(*(std::declval<Container>()).data())>::type,
-          typename = decltype((std::declval<Container>()).size())>
-inline constexpr Vector<T> VectorOf(Container&& c) {
-  return Vector<T>(c.data(), c.size());
+template <typename Container>
+inline constexpr auto VectorOf(Container&& c)
+    -> decltype(VectorOf(c.data(), c.size())) {
+  return VectorOf(c.data(), c.size());
 }
 
 }  // namespace internal

src/wasm/baseline/liftoff-assembler.cc

@@ -328,11 +328,10 @@ void LiftoffAssembler::CacheState::InitMerge(const CacheState& source,
   // multiple times need to be copied to another free register. Compute the list
   // of used registers.
   LiftoffRegList used_regs;
-  for (auto& src : Vector<const VarState>{source_begin, num_locals}) {
+  for (auto& src : VectorOf(source_begin, num_locals)) {
     if (src.is_reg()) used_regs.set(src.reg());
   }
-  for (auto& src :
-       Vector<const VarState>{source_begin + stack_base + discarded, arity}) {
+  for (auto& src : VectorOf(source_begin + stack_base + discarded, arity)) {
     if (src.is_reg()) used_regs.set(src.reg());
   }
 

src/wasm/module-compiler.cc

@@ -3395,8 +3395,7 @@ Handle<Script> CreateWasmScript(Isolate* isolate,
   int name_chars = SNPrintF(ArrayVector(buffer), "wasm-%08x", hash);
   DCHECK(name_chars >= 0 && name_chars < kBufferSize);
   MaybeHandle<String> name_str = isolate->factory()->NewStringFromOneByte(
-      Vector<const uint8_t>(reinterpret_cast<uint8_t*>(buffer), name_chars),
-      TENURED);
+      VectorOf(reinterpret_cast<uint8_t*>(buffer), name_chars), TENURED);
   script->set_name(*name_str.ToHandleChecked());
 
   if (source_map_url.size() != 0) {

src/wasm/module-decoder.cc

@@ -1025,7 +1025,7 @@ class ModuleDecoderImpl : public Decoder {
     StartDecoding(counters, allocator);
     uint32_t offset = 0;
     Vector<const byte> orig_bytes(start(), end() - start());
-    DecodeModuleHeader(Vector<const uint8_t>(start(), end() - start()), offset);
+    DecodeModuleHeader(VectorOf(start(), end() - start()), offset);
     if (failed()) {
       return FinishDecoding(verify_functions);
     }

src/wasm/wasm-js.cc

@@ -42,7 +42,7 @@ class WasmStreaming::WasmStreamingImpl {
   }
 
   void OnBytesReceived(const uint8_t* bytes, size_t size) {
-    streaming_decoder_->OnBytesReceived(i::Vector<const uint8_t>(bytes, size));
+    streaming_decoder_->OnBytesReceived(i::VectorOf(bytes, size));
   }
   void Finish() { streaming_decoder_->Finish(); }
 
@@ -338,20 +338,14 @@ class InstantiateBytesResultResolver
     i::Handle<i::JSObject> result =
         isolate_->factory()->NewJSObject(isolate_->object_function());
 
-    const uint8_t* instance_str = reinterpret_cast<const uint8_t*>("instance");
     i::Handle<i::String> instance_name =
         isolate_->factory()
-            ->NewStringFromOneByte(i::Vector<const uint8_t>(
-                instance_str,
-                i::StrLength(reinterpret_cast<const char*>(instance_str))))
+            ->NewStringFromOneByte(STATIC_CHAR_VECTOR("instance"))
             .ToHandleChecked();
 
-    const uint8_t* module_str = reinterpret_cast<const uint8_t*>("module");
     i::Handle<i::String> module_name =
         isolate_->factory()
-            ->NewStringFromOneByte(i::Vector<const uint8_t>(
-                module_str,
-                i::StrLength(reinterpret_cast<const char*>(module_str))))
+            ->NewStringFromOneByte(STATIC_CHAR_VECTOR("module"))
             .ToHandleChecked();
 
     i::JSObject::AddProperty(isolate_, result, instance_name, instance,