[csa][cleanup] TNodify AtomicLoad and thereby all uses of Projection.

Introduces an AtomicUint64 type and a seperate AtomicLoad64 due to the
different types returned by loading 64-bit atomic values on 32-bit vs
64-bit architectures.

BUG=v8:6949,v8:11074

Change-Id: I95de994df9639847cd6b5fd56ea2a6585189ed3a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2529455
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Auto-Submit: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71110}

src/builtins/builtins-sharedarraybuffer-gen.cc

@@ -43,8 +43,8 @@ class SharedArrayBufferBuiltinsAssembler : public CodeStubAssembler {
 
   // Create a BigInt from the result of a 64-bit atomic operation, using
   // projections on 32-bit platforms.
-  TNode<BigInt> BigIntFromSigned64(Node* signed64);
+  TNode<BigInt> BigIntFromSigned64(SloppyTNode<AtomicInt64> signed64);
-  TNode<BigInt> BigIntFromUnsigned64(Node* unsigned64);
+  TNode<BigInt> BigIntFromUnsigned64(SloppyTNode<AtomicUint64> unsigned64);
 };
 
 // https://tc39.es/ecma262/#sec-validateintegertypedarray
@@ -142,25 +142,25 @@ void SharedArrayBufferBuiltinsAssembler::DebugCheckAtomicIndex(
 }
 
 TNode<BigInt> SharedArrayBufferBuiltinsAssembler::BigIntFromSigned64(
-    Node* signed64) {
+    SloppyTNode<AtomicInt64> signed64) {
-  if (Is64()) {
+#if defined(V8_HOST_ARCH_32_BIT)
-    return BigIntFromInt64(UncheckedCast<IntPtrT>(signed64));
+  TNode<IntPtrT> low = Projection<0>(signed64);
-  } else {
+  TNode<IntPtrT> high = Projection<1>(signed64);
-    TNode<IntPtrT> low = UncheckedCast<IntPtrT>(Projection(0, signed64));
+  return BigIntFromInt32Pair(low, high);
-    TNode<IntPtrT> high = UncheckedCast<IntPtrT>(Projection(1, signed64));
+#else
-    return BigIntFromInt32Pair(low, high);
+  return BigIntFromInt64(signed64);
-  }
+#endif
 }
 
 TNode<BigInt> SharedArrayBufferBuiltinsAssembler::BigIntFromUnsigned64(
-    Node* unsigned64) {
+    SloppyTNode<AtomicUint64> unsigned64) {
-  if (Is64()) {
+#if defined(V8_HOST_ARCH_32_BIT)
-    return BigIntFromUint64(UncheckedCast<UintPtrT>(unsigned64));
+  TNode<UintPtrT> low = Projection<0>(unsigned64);
-  } else {
+  TNode<UintPtrT> high = Projection<1>(unsigned64);
-    TNode<UintPtrT> low = UncheckedCast<UintPtrT>(Projection(0, unsigned64));
+  return BigIntFromUint32Pair(low, high);
-    TNode<UintPtrT> high = UncheckedCast<UintPtrT>(Projection(1, unsigned64));
+#else
-    return BigIntFromUint32Pair(low, high);
+  return BigIntFromUint64(unsigned64);
-  }
+#endif
 }
 
 // https://tc39.es/ecma262/#sec-atomicload
@@ -201,28 +201,26 @@ TF_BUILTIN(AtomicsLoad, SharedArrayBufferBuiltinsAssembler) {
          arraysize(case_labels));
 
   BIND(&i8);
-  Return(
+  Return(SmiFromInt32(AtomicLoad<Int8T>(backing_store, index_word)));
-      SmiFromInt32(AtomicLoad(MachineType::Int8(), backing_store, index_word)));
 
   BIND(&u8);
-  Return(SmiFromInt32(
+  Return(SmiFromInt32(AtomicLoad<Uint8T>(backing_store, index_word)));
-      AtomicLoad(MachineType::Uint8(), backing_store, index_word)));
 
   BIND(&i16);
-  Return(SmiFromInt32(
+  Return(
-      AtomicLoad(MachineType::Int16(), backing_store, WordShl(index_word, 1))));
+      SmiFromInt32(AtomicLoad<Int16T>(backing_store, WordShl(index_word, 1))));
 
   BIND(&u16);
-  Return(SmiFromInt32(AtomicLoad(MachineType::Uint16(), backing_store,
+  Return(
-                                 WordShl(index_word, 1))));
+      SmiFromInt32(AtomicLoad<Uint16T>(backing_store, WordShl(index_word, 1))));
 
   BIND(&i32);
   Return(ChangeInt32ToTagged(
-      AtomicLoad(MachineType::Int32(), backing_store, WordShl(index_word, 2))));
+      AtomicLoad<Int32T>(backing_store, WordShl(index_word, 2))));
 
   BIND(&u32);
-  Return(ChangeUint32ToTagged(AtomicLoad(MachineType::Uint32(), backing_store,
+  Return(ChangeUint32ToTagged(
-                                         WordShl(index_word, 2))));
+      AtomicLoad<Uint32T>(backing_store, WordShl(index_word, 2))));
 #if V8_TARGET_ARCH_MIPS && !_MIPS_ARCH_MIPS32R6
   BIND(&i64);
   Goto(&u64);
@@ -234,15 +232,12 @@ TF_BUILTIN(AtomicsLoad, SharedArrayBufferBuiltinsAssembler) {
   }
 #else
   BIND(&i64);
-  // This uses Uint64() intentionally: AtomicLoad is not implemented for
+  Return(BigIntFromSigned64(
-  // Int64(), which is fine because the machine instruction only cares
+      AtomicLoad64<AtomicInt64>(backing_store, WordShl(index_word, 3))));
-  // about words.
-  Return(BigIntFromSigned64(AtomicLoad(MachineType::Uint64(), backing_store,
-                                       WordShl(index_word, 3))));
 
   BIND(&u64);
-  Return(BigIntFromUnsigned64(AtomicLoad(MachineType::Uint64(), backing_store,
+  Return(BigIntFromUnsigned64(
-                                         WordShl(index_word, 3))));
+      AtomicLoad64<AtomicUint64>(backing_store, WordShl(index_word, 3))));
 #endif
 
   // This shouldn't happen, we've already validated the type.

src/compiler/code-assembler.cc

@@ -667,10 +667,22 @@ TNode<Object> CodeAssembler::LoadFullTagged(Node* base, Node* offset,
       Load(MachineType::Pointer(), base, offset, needs_poisoning));
 }
 
-Node* CodeAssembler::AtomicLoad(MachineType type, Node* base, Node* offset) {
+Node* CodeAssembler::AtomicLoad(MachineType type, TNode<RawPtrT> base,
+                                TNode<WordT> offset) {
   return raw_assembler()->AtomicLoad(type, base, offset);
 }
 
+template <class Type>
+TNode<Type> CodeAssembler::AtomicLoad64(TNode<RawPtrT> base,
+                                        TNode<WordT> offset) {
+  return UncheckedCast<Type>(raw_assembler()->AtomicLoad64(base, offset));
+}
+
+template TNode<AtomicInt64> CodeAssembler::AtomicLoad64<AtomicInt64>(
+    TNode<RawPtrT> base, TNode<WordT> offset);
+template TNode<AtomicUint64> CodeAssembler::AtomicLoad64<AtomicUint64>(
+    TNode<RawPtrT> base, TNode<WordT> offset);
+
 Node* CodeAssembler::LoadFromObject(MachineType type, TNode<HeapObject> object,
                                     TNode<IntPtrT> offset) {
   return raw_assembler()->LoadFromObject(type, object, offset);

src/compiler/code-assembler.h

@@ -178,6 +178,20 @@ HEAP_OBJECT_TEMPLATE_TYPE_LIST(OBJECT_TYPE_TEMPLATE_CASE)
 #undef OBJECT_TYPE_STRUCT_CASE
 #undef OBJECT_TYPE_TEMPLATE_CASE
 
+#if defined(V8_HOST_ARCH_32_BIT)
+#define BINT_IS_SMI
+using BInt = Smi;
+using AtomicInt64 = PairT<IntPtrT, IntPtrT>;
+using AtomicUint64 = PairT<UintPtrT, UintPtrT>;
+#elif defined(V8_HOST_ARCH_64_BIT)
+#define BINT_IS_INTPTR
+using BInt = IntPtrT;
+using AtomicInt64 = IntPtrT;
+using AtomicUint64 = UintPtrT;
+#else
+#error Unknown architecture.
+#endif
+
 // {raw_value} must be a tagged Object.
 // {raw_type} must be a tagged Smi.
 // {raw_location} must be a tagged String.
@@ -731,7 +745,13 @@ class V8_EXPORT_PRIVATE CodeAssembler {
     return UncheckedCast<Type>(
         Load(MachineTypeOf<Type>::value, base, offset, needs_poisoning));
   }
-  Node* AtomicLoad(MachineType type, Node* base, Node* offset);
+  template <class Type>
+  TNode<Type> AtomicLoad(TNode<RawPtrT> base, TNode<WordT> offset) {
+    return UncheckedCast<Type>(
+        AtomicLoad(MachineTypeOf<Type>::value, base, offset));
+  }
+  template <class Type>
+  TNode<Type> AtomicLoad64(TNode<RawPtrT> base, TNode<WordT> offset);
   // Load uncompressed tagged value from (most likely off JS heap) memory
   // location.
   TNode<Object> LoadFullTagged(
@@ -992,8 +1012,6 @@ class V8_EXPORT_PRIVATE CodeAssembler {
   TNode<Int32T> TruncateFloat32ToInt32(SloppyTNode<Float32T> value);
 
   // Projections
-  Node* Projection(int index, Node* value);
-
   template <int index, class T1, class T2>
   TNode<typename std::tuple_element<index, std::tuple<T1, T2>>::type>
   Projection(TNode<PairT<T1, T2>> value) {
@@ -1232,11 +1250,15 @@ class V8_EXPORT_PRIVATE CodeAssembler {
                   const CallInterfaceDescriptor& descriptor, int input_count,
                   Node* const* inputs);
 
+  Node* AtomicLoad(MachineType type, TNode<RawPtrT> base, TNode<WordT> offset);
+
   // These two don't have definitions and are here only for catching use cases
   // where the cast is not necessary.
   TNode<Int32T> Signed(TNode<Int32T> x);
   TNode<Uint32T> Unsigned(TNode<Uint32T> x);
 
+  Node* Projection(int index, Node* value);
+
   RawMachineAssembler* raw_assembler() const;
   JSGraph* jsgraph() const;
 
@@ -1533,17 +1555,6 @@ class V8_EXPORT_PRIVATE ScopedExceptionHandler {
 };
 
 }  // namespace compiler
-
-#if defined(V8_HOST_ARCH_32_BIT)
-#define BINT_IS_SMI
-using BInt = Smi;
-#elif defined(V8_HOST_ARCH_64_BIT)
-#define BINT_IS_INTPTR
-using BInt = IntPtrT;
-#else
-#error Unknown architecture.
-#endif
-
 }  // namespace internal
 }  // namespace v8
 

src/compiler/raw-machine-assembler.h

@@ -221,16 +221,22 @@ class V8_EXPORT_PRIVATE RawMachineAssembler {
 
   // Atomic memory operations.
   Node* AtomicLoad(MachineType type, Node* base, Node* index) {
-    if (type.representation() == MachineRepresentation::kWord64) {
+    DCHECK_NE(type.representation(), MachineRepresentation::kWord64);
-      if (machine()->Is64()) {
-        return AddNode(machine()->Word64AtomicLoad(type), base, index);
-      } else {
-        return AddNode(machine()->Word32AtomicPairLoad(), base, index);
-      }
-    }
     return AddNode(machine()->Word32AtomicLoad(type), base, index);
   }
 
+  Node* AtomicLoad64(Node* base, Node* index) {
+    if (machine()->Is64()) {
+      // This uses Uint64() intentionally: AtomicLoad is not implemented for
+      // Int64(), which is fine because the machine instruction only cares
+      // about words.
+      return AddNode(machine()->Word64AtomicLoad(MachineType::Uint64()), base,
+                     index);
+    } else {
+      return AddNode(machine()->Word32AtomicPairLoad(), base, index);
+    }
+  }
+
 #if defined(V8_TARGET_BIG_ENDIAN)
 #define VALUE_HALVES value_high, value
 #else