[wasm] remove faux code objects

src/compiler/wasm-compiler.cc

Index: src/compiler/wasm-compiler.cc
diff --git a/src/compiler/wasm-compiler.cc b/src/compiler/wasm-compiler.cc
index 1d547113d270d6536bf719d10750dd6e8467b4f5..2db46c38fd0fe207282ca6fe859c17ad27438b76 100644
--- a/src/compiler/wasm-compiler.cc
+++ b/src/compiler/wasm-compiler.cc
@@ -1874,7 +1874,8 @@ Node* WasmGraphBuilder::BuildCCall(MachineSignature* sig, Node** args) {
 }
 
 Node* WasmGraphBuilder::BuildWasmCall(wasm::FunctionSig* sig, Node** args,
-                                      wasm::WasmCodePosition position) {
+                                      wasm::WasmCodePosition position,
+                                      bool internal) {
   const size_t params = sig->parameter_count();
   const size_t extra = 2;  // effect and control inputs.
   const size_t count = 1 + params + extra;
@@ -1887,7 +1888,7 @@ Node* WasmGraphBuilder::BuildWasmCall(wasm::FunctionSig* sig, Node** args,
   args[params + 2] = *control_;
 
   CallDescriptor* descriptor =
-      wasm::ModuleEnv::GetWasmCallDescriptor(jsgraph()->zone(), sig);
+      wasm::ModuleEnv::GetWasmCallDescriptor(jsgraph()->zone(), sig, internal);
   const Operator* op = jsgraph()->common()->Call(descriptor);
   Node* call = graph()->NewNode(op, static_cast<int>(count), args);
   SetSourcePosition(call, position);
@@ -1900,22 +1901,21 @@ Node* WasmGraphBuilder::CallDirect(uint32_t index, Node** args,
                                    wasm::WasmCodePosition position) {
   DCHECK_NULL(args[0]);
 
-  // Add code object as constant.
-  args[0] = HeapConstant(module_->GetCodeOrPlaceholder(index));
+  args[0] =
+      jsgraph()->RelocatableInt32Constant(index, RelocInfo::WASM_DIRECT_CALL);
   wasm::FunctionSig* sig = module_->GetFunctionSignature(index);
 
-  return BuildWasmCall(sig, args, position);
+  return BuildWasmCall(sig, args, position, true);
 }
 
 Node* WasmGraphBuilder::CallImport(uint32_t index, Node** args,
                                    wasm::WasmCodePosition position) {
   DCHECK_NULL(args[0]);
 
-  // Add code object as constant.
-  args[0] = HeapConstant(module_->GetImportCode(index));
+  args[0] =
+      jsgraph()->RelocatableInt32Constant(index, RelocInfo::WASM_IMPORT_CALL);
   wasm::FunctionSig* sig = module_->GetImportSignature(index);
-
-  return BuildWasmCall(sig, args, position);
+  return BuildWasmCall(sig, args, position, true);
 }
 
 Node* WasmGraphBuilder::CallIndirect(uint32_t index, Node** args,
@@ -3302,6 +3302,43 @@ Handle<Code> WasmCompilationUnit::FinishCompilation() {
   return code;
 }
 
+void Link(Isolate* isolate, std::vector<Handle<Code>>& unlinked_functions,
+          const std::vector<Handle<Code>>& functions_to_link, int mode_mask) {
+  // On architectures supporting constant pools, if a function A calls another
+  // function B in a number of places, then the same slot in the constant pool
+  // would be used for the call to B. We can't update eagerly the location,
+  // because that would mean that the next time we look at the location to find
+  // the index of the function being called, we'd find the actual address
+  // instead. So we keep a worklist. To keep the code simple, we maintain the
+  // worklist even on architectures that do not support constant pools.
+
+  std::vector<std::pair<RelocInfo, Address>> worklist;
+  {
+    DisallowHeapAllocation no_gc_scope;
+    RelocInfoWriter writer;
+    for (Handle<Code> code : unlinked_functions) {
+      AllowDeferredHandleDereference embedding_raw_address;
+      for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
+        size_t f_index = it.rinfo()->wasm_function_index();
+        Handle<Code> to_link = functions_to_link[f_index];
+        worklist.push_back(
+            std::make_pair(*it.rinfo(), to_link->instruction_start()));
+        writer.Reposition(it.mode_pos(), it.rinfo()->pc());
+        writer.WriteModeNoAdvance(RelocInfo::CODE_TARGET);
+      }
+      for (auto pair : worklist) {
+        pair.first.set_target_address(pair.second, SKIP_WRITE_BARRIER,
+                                      SKIP_ICACHE_FLUSH);
+      }
+      if (!worklist.empty()) {
+        worklist.clear();
+        Assembler::FlushICache(isolate, code->instruction_start(),
+                               code->instruction_size());
+      }
+    }
+  }
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8