[wasm] Fix Int64-lowering to handle non-const index for I64Atomic ops

Bug: chromium:925244
Change-Id: If9c00f85b1dece93057b541bf0fe1b0a05b81ceb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1565032
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60795}

src/compiler/int64-lowering.cc

@@ -119,6 +119,7 @@ int GetReturnCountAfterLowering(Signature<MachineRepresentation>* signature) {
 
 void Int64Lowering::LowerWord64AtomicBinop(Node* node, const Operator* op) {
   DCHECK_EQ(5, node->InputCount());
+  LowerMemoryBaseAndIndex(node);
   Node* value = node->InputAt(2);
   node->ReplaceInput(2, GetReplacementLow(value));
   node->InsertInput(zone(), 3, GetReplacementHigh(value));
@@ -143,9 +144,6 @@ int Int64Lowering::GetParameterCountAfterLowering(
 
 void Int64Lowering::GetIndexNodes(Node* index, Node*& index_low,
                                   Node*& index_high) {
-  if (HasReplacementLow(index)) {
-    index = GetReplacementLow(index);
-  }
 #if defined(V8_TARGET_LITTLE_ENDIAN)
   index_low = index;
   index_high = graph()->NewNode(machine()->Int32Add(), index,
@@ -179,6 +177,7 @@ void Int64Lowering::LowerNode(Node* node) {
       }
 
       if (rep == MachineRepresentation::kWord64) {
+        LowerMemoryBaseAndIndex(node);
         Node* base = node->InputAt(0);
         Node* index = node->InputAt(1);
         Node* index_low;
@@ -228,6 +227,7 @@ void Int64Lowering::LowerNode(Node* node) {
         // a new store node to store the high word. The effect and control edges
         // are copied from the original store to the new store node, the effect
         // edge of the original store is redirected to the new store.
+        LowerMemoryBaseAndIndex(node);
         Node* base = node->InputAt(0);
         Node* index = node->InputAt(1);
         Node* index_low;
@@ -900,6 +900,7 @@ void Int64Lowering::LowerNode(Node* node) {
       DCHECK_EQ(5, node->InputCount());
       MachineRepresentation rep = AtomicStoreRepresentationOf(node->op());
       if (rep == MachineRepresentation::kWord64) {
+        LowerMemoryBaseAndIndex(node);
         Node* value = node->InputAt(2);
         node->ReplaceInput(2, GetReplacementLow(value));
         node->InsertInput(zone(), 3, GetReplacementHigh(value));
@@ -930,6 +931,7 @@ void Int64Lowering::LowerNode(Node* node) {
     case IrOpcode::kWord64AtomicCompareExchange: {
       MachineType type = AtomicOpType(node->op());
       if (type == MachineType::Uint64()) {
+        LowerMemoryBaseAndIndex(node);
         Node* old_value = node->InputAt(2);
         Node* new_value = node->InputAt(3);
         node->ReplaceInput(2, GetReplacementLow(old_value));
@@ -1051,6 +1053,19 @@ void Int64Lowering::ReplaceNodeWithProjections(Node* node) {
   ReplaceNode(node, low_node, high_node);
 }
 
+void Int64Lowering::LowerMemoryBaseAndIndex(Node* node) {
+  DCHECK(node != nullptr);
+  // Low word only replacements for memory operands for 32-bit address space.
+  Node* base = node->InputAt(0);
+  Node* index = node->InputAt(1);
+  if (HasReplacementLow(base)) {
+    node->ReplaceInput(0, GetReplacementLow(base));
+  }
+  if (HasReplacementLow(index)) {
+    node->ReplaceInput(1, GetReplacementLow(index));
+  }
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8

src/compiler/int64-lowering.h

@@ -61,6 +61,7 @@ class V8_EXPORT_PRIVATE Int64Lowering {
   void PreparePhiReplacement(Node* phi);
   void GetIndexNodes(Node* index, Node*& index_low, Node*& index_high);
   void ReplaceNodeWithProjections(Node* node);
+  void LowerMemoryBaseAndIndex(Node* node);
 
   struct NodeState {
     Node* node;

test/cctest/wasm/test-run-wasm-atomics64.cc

@@ -541,14 +541,23 @@ void RunNonConstIndexTest(ExecutionTier execution_tier, WasmOpcode wasm_op,
            static_cast<uint32_t>(r.builder().ReadMemory(&memory[0])));
 }
 
+// Test a set of Narrow operations
 #define TEST_OPERATION(Name)                                               \
-  WASM_EXEC_TEST(I64AtomicConstIndex##Name) {                              \
+  WASM_EXEC_TEST(I64AtomicConstIndex##Name##Narrow) {                      \
     RunNonConstIndexTest(execution_tier, kExprI64Atomic##Name##32U, Name); \
   }
 OPERATION_LIST(TEST_OPERATION)
 #undef TEST_OPERATION
 
-WASM_EXEC_TEST(I64AtomicNonConstIndexCompareExchange) {
+// Test a set of Regular operations
+#define TEST_OPERATION(Name)                                          \
+  WASM_EXEC_TEST(I64AtomicConstIndex##Name) {                         \
+    RunNonConstIndexTest(execution_tier, kExprI64Atomic##Name, Name); \
+  }
+OPERATION_LIST(TEST_OPERATION)
+#undef TEST_OPERATION
+
+WASM_EXEC_TEST(I64AtomicNonConstIndexCompareExchangeNarrow) {
   EXPERIMENTAL_FLAG_SCOPE(threads);
   WasmRunner<uint32_t, uint64_t, uint64_t> r(execution_tier);
   uint64_t* memory =
@@ -567,6 +576,25 @@ WASM_EXEC_TEST(I64AtomicNonConstIndexCompareExchange) {
            static_cast<uint16_t>(r.builder().ReadMemory(&memory[0])));
 }
 
+WASM_EXEC_TEST(I64AtomicNonConstIndexCompareExchange) {
+  EXPERIMENTAL_FLAG_SCOPE(threads);
+  WasmRunner<uint32_t, uint64_t, uint64_t> r(execution_tier);
+  uint64_t* memory =
+      r.builder().AddMemoryElems<uint64_t>(kWasmPageSize / sizeof(uint64_t));
+  r.builder().SetHasSharedMemory();
+
+  BUILD(r, WASM_I32_CONVERT_I64(WASM_ATOMICS_TERNARY_OP(
+               kExprI64AtomicCompareExchange,
+               WASM_I64_EQ(WASM_I64V(1), WASM_I64V(0)), WASM_GET_LOCAL(0),
+               WASM_GET_LOCAL(1), MachineRepresentation::kWord16)));
+
+  uint64_t initial = 4444333322221111, local = 0x9999888877776666;
+  r.builder().WriteMemory(&memory[0], initial);
+  CHECK_EQ(static_cast<uint32_t>(initial), r.Call(initial, local));
+  CHECK_EQ(CompareExchange(initial, initial, local),
+           r.builder().ReadMemory(&memory[0]));
+}
+
 WASM_EXEC_TEST(I64AtomicNonConstIndexLoad8U) {
   EXPERIMENTAL_FLAG_SCOPE(threads);
   WasmRunner<uint32_t> r(execution_tier);