[wasm] support calling an imported func that returns a i64

It removes the assertion that caused the bug report by introducing a new
trampoline (WasmBigIntToI64) for the conversion code stub between a Bigint
object and a Wasm i64 BigIntToI64).

The tests were updated to cover calling the stub from a Wasm callsite.

Bug: v8:8625
Change-Id: I55891001cfa72f6f2849792293b43bbb54147f1a
Reviewed-on: https://chromium-review.googlesource.com/c/1405028
Commit-Queue: Sven Sauleau <ssauleau@igalia.com>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58767}

src/builtins/builtins-definitions.h

@@ -1260,6 +1260,7 @@ namespace internal {
   TFS(ThrowWasmTrapFuncSigMismatch)                                            \
   TFS(ThrowWasmTrapDataSegmentDropped)                                         \
   TFC(BigIntToWasmI64, BigIntToWasmI64, 1)                                     \
+  TFC(WasmBigIntToI64, BigIntToI64, 1)                                         \
                                                                                \
   /* WeakMap */                                                                \
   TFJ(WeakMapConstructor, SharedFunctionInfo::kDontAdaptArgumentsSentinel)     \
@@ -1551,7 +1552,8 @@ namespace internal {
   V(WasmToNumber)                        \
   V(WasmThrow)                           \
   V(DoubleToI)                           \
-  V(BigIntToWasmI64)
+  V(BigIntToWasmI64)                     \
+  V(WasmBigIntToI64)
 
 // The exception thrown in the following builtins are caught internally and will
 // not be propagated further or re-thrown

src/builtins/builtins-wasm-gen.cc

@@ -233,6 +233,21 @@ TF_BUILTIN(BigIntToWasmI64, WasmBuiltinsAssembler) {
                argument);
 }
 
+TF_BUILTIN(WasmBigIntToI64, WasmBuiltinsAssembler) {
+  if (!Is64()) {
+    Unreachable();
+    return;
+  }
+
+  TNode<Object> context =
+      UncheckedCast<Object>(Parameter(Descriptor::kContext));
+  TNode<Code> target = LoadBuiltinFromFrame(Builtins::kBigIntToI64);
+  TNode<IntPtrT> argument =
+      UncheckedCast<IntPtrT>(Parameter(Descriptor::kArgument));
+
+  TailCallStub(BigIntToI64Descriptor(), target, context, argument);
+}
+
 #define DECLARE_ENUM(name)                                                \
   TF_BUILTIN(ThrowWasm##name, WasmBuiltinsAssembler) {                    \
     TNode<Object> instance = LoadInstanceFromFrame();                     \

src/compiler/wasm-compiler.cc

@@ -4710,8 +4710,6 @@ class WasmWrapperGraphBuilder : public WasmGraphBuilder {
   }
 
   Node* BuildChangeBigIntToInt64(Node* input, Node* context) {
-    DCHECK_EQ(stub_mode_, StubCallMode::kCallCodeObject);
-
     BigIntToI64Descriptor interface_descriptor;
 
     auto call_descriptor = Linkage::GetStubCallDescriptor(
@@ -4720,9 +4718,13 @@ class WasmWrapperGraphBuilder : public WasmGraphBuilder {
         interface_descriptor.GetStackParameterCount(),  // stack parameter count
         CallDescriptor::kNoFlags,                       // flags
         Operator::kNoProperties,                        // properties
-        StubCallMode::kCallCodeObject);                 // stub call mode
+        stub_mode_);                                    // stub call mode
 
-    Node* target = jsgraph()->HeapConstant(BUILTIN_CODE(isolate_, BigIntToI64));
+    Node* target =
+        (stub_mode_ == StubCallMode::kCallWasmRuntimeStub)
+            ? mcgraph()->RelocatableIntPtrConstant(
+                  wasm::WasmCode::kWasmBigIntToI64, RelocInfo::WASM_STUB_CALL)
+            : jsgraph()->HeapConstant(BUILTIN_CODE(isolate_, BigIntToI64));
 
     return SetEffect(SetControl(
         graph()->NewNode(mcgraph()->common()->Call(call_descriptor), target,

test/mjsunit/wasm/bigint.js

@@ -27,12 +27,12 @@ load("test/mjsunit/wasm/wasm-module-builder.js");
   var builder = new WasmModuleBuilder();
 
   var a_index = builder
-    .addImport("a", "a", kSig_v_l) // i64 -> ()
+    .addImport("a", "a", kSig_l_l) // i64 -> i64
 
   builder
-    .addFunction("fn", kSig_v_v) // () -> ()
+    .addFunction("fn", kSig_l_v) // () -> i64
     .addBody([
-      kExprI64Const, 0x1,
+      kExprI64Const, 0x7,
       kExprCallFunction, a_index
     ])
     .exportFunc();
@@ -43,13 +43,14 @@ load("test/mjsunit/wasm/wasm-module-builder.js");
     a: {
       a(param) {
         assertEquals(typeof param, "bigint");
-        assertEquals(param, 1n);
+        assertEquals(param, 7n);
         a_was_called = true;
+        return 12n;
       },
     }
   });
 
-  module.exports.fn();
+  assertEquals(module.exports.fn(), 12n);
 
   assertTrue(a_was_called);
 })();