From cb37b6c54eb90bab459c140c9965c89b6196d1f4 Mon Sep 17 00:00:00 2001
From: "bmeurer@chromium.org" <bmeurer@chromium.org>
Date: Fri, 10 Oct 2014 08:10:29 +0000
Subject: [PATCH] [turbofan] Fix typed lowering of typed array loads/stores.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/646483003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24514 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
---
 src/compiler/js-typed-lowering.cc | 67 +++++++++++++++++++++------------------
 src/factory.cc                    | 17 +++++++++-
 2 files changed, 52 insertions(+), 32 deletions(-)

diff --git a/src/compiler/js-typed-lowering.cc b/src/compiler/js-typed-lowering.cc
index 05e8ede..557b027 100644
--- a/src/compiler/js-typed-lowering.cc
+++ b/src/compiler/js-typed-lowering.cc
@@ -541,21 +541,24 @@ Reduction JSTypedLowering::ReduceJSLoadProperty(Node* node) {
         Handle<JSTypedArray>::cast(base_type->AsConstant()->Value());
     if (IsExternalArrayElementsKind(array->map()->elements_kind())) {
       ExternalArrayType type = array->type();
-      uint32_t length;
-      CHECK(array->length()->ToUint32(&length));
-      Node* elements = graph()->NewNode(
-          simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base,
-          graph()->start());
-      Node* pointer = graph()->NewNode(
-          simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()),
-          elements, elements);
-      Node* effect = NodeProperties::GetEffectInput(node);
-      Node* control = NodeProperties::GetControlInput(node);
-      Node* load = graph()->NewNode(
-          simplified()->LoadElement(
-              AccessBuilder::ForTypedArrayElement(type, true)),
-          pointer, key, jsgraph()->Uint32Constant(length), effect, control);
-      return ReplaceEagerly(node, load);
+      uint32_t byte_length;
+      if (array->byte_length()->ToUint32(&byte_length)) {
+        Node* elements = graph()->NewNode(
+            simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base,
+            graph()->start());
+        Node* pointer = graph()->NewNode(
+            simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()),
+            elements, elements);
+        Node* length = jsgraph()->Uint32Constant(
+            static_cast<uint32_t>(byte_length / array->element_size()));
+        Node* effect = NodeProperties::GetEffectInput(node);
+        Node* control = NodeProperties::GetControlInput(node);
+        Node* load = graph()->NewNode(
+            simplified()->LoadElement(
+                AccessBuilder::ForTypedArrayElement(type, true)),
+            pointer, key, length, effect, control);
+        return ReplaceEagerly(node, load);
+      }
     }
   }
   return NoChange();
@@ -577,22 +580,24 @@ Reduction JSTypedLowering::ReduceJSStoreProperty(Node* node) {
         Handle<JSTypedArray>::cast(base_type->AsConstant()->Value());
     if (IsExternalArrayElementsKind(array->map()->elements_kind())) {
       ExternalArrayType type = array->type();
-      uint32_t length;
-      CHECK(array->length()->ToUint32(&length));
-      Node* elements = graph()->NewNode(
-          simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base,
-          graph()->start());
-      Node* pointer = graph()->NewNode(
-          simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()),
-          elements, elements);
-      Node* effect = NodeProperties::GetEffectInput(node);
-      Node* control = NodeProperties::GetControlInput(node);
-      Node* store =
-          graph()->NewNode(simplified()->StoreElement(
-                               AccessBuilder::ForTypedArrayElement(type, true)),
-                           pointer, key, jsgraph()->Uint32Constant(length),
-                           value, effect, control);
-      return ReplaceEagerly(node, store);
+      uint32_t byte_length;
+      if (array->byte_length()->ToUint32(&byte_length)) {
+        Node* elements = graph()->NewNode(
+            simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base,
+            graph()->start());
+        Node* pointer = graph()->NewNode(
+            simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()),
+            elements, elements);
+        Node* length = jsgraph()->Uint32Constant(
+            static_cast<uint32_t>(byte_length / array->element_size()));
+        Node* effect = NodeProperties::GetEffectInput(node);
+        Node* control = NodeProperties::GetControlInput(node);
+        Node* store = graph()->NewNode(
+            simplified()->StoreElement(
+                AccessBuilder::ForTypedArrayElement(type, true)),
+            pointer, key, length, value, effect, control);
+        return ReplaceEagerly(node, store);
+      }
     }
   }
   return NoChange();
diff --git a/src/factory.cc b/src/factory.cc
index 25d8cd8..60ea691 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -1731,6 +1731,19 @@ ElementsKind GetExternalArrayElementsKind(ExternalArrayType type) {
 }
 
 
+size_t GetExternalArrayElementSize(ExternalArrayType type) {
+  switch (type) {
+#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
+  case kExternal##Type##Array:                          \
+    return size;
+    TYPED_ARRAYS(TYPED_ARRAY_CASE)
+  }
+  UNREACHABLE();
+  return 0;
+#undef TYPED_ARRAY_CASE
+}
+
+
 JSFunction* GetTypedArrayFun(ExternalArrayType type, Isolate* isolate) {
   Context* native_context = isolate->context()->native_context();
   switch (type) {
@@ -1769,7 +1782,9 @@ Handle<JSTypedArray> Factory::NewJSTypedArray(ExternalArrayType type,
   array->set_weak_next(buffer->weak_first_view());
   buffer->set_weak_first_view(*array);
   array->set_byte_offset(Smi::FromInt(0));
-  array->set_byte_length(buffer->byte_length());
+  Handle<Object> byte_length_handle =
+      NewNumberFromSize(length * GetExternalArrayElementSize(type));
+  array->set_byte_length(*byte_length_handle);
   Handle<Object> length_handle = NewNumberFromSize(length);
   array->set_length(*length_handle);
   Handle<ExternalArray> elements =
-- 
2.7.4