Refactor InterpreterPushArgsThenConstruct

This reorders arguments in preparation for removing ebx from its
calling convention (in a follow-up some args will be passed on the
stack).

Drive-by: Improve readability in the code handling different cases
(array,spread,...).

Bug: v8:6666
Change-Id: I0160f8efafd0fd0e841739578e01c32b38adb66e
Reviewed-on: https://chromium-review.googlesource.com/1196884Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55557}

src/arm/interface-descriptors-arm.cc

@@ -237,10 +237,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       r0,  // argument count (not including receiver)
-      r3,  // new target
+      r4,  // address of the first argument
       r1,  // constructor to call
+      r3,  // new target
       r2,  // allocation site feedback if available, undefined otherwise
-      r4   // address of the first argument
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/arm64/interface-descriptors-arm64.cc

@@ -242,10 +242,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       x0,  // argument count (not including receiver)
-      x3,  // new target
+      x4,  // address of the first argument
       x1,  // constructor to call
+      x3,  // new target
       x2,  // allocation site feedback if available, undefined otherwise
-      x4   // address of the first argument
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/builtins/ia32/builtins-ia32.cc

@@ -1110,29 +1110,26 @@ void Builtins::Generate_InterpreterPushArgsThenConstructImpl(
   __ Pop(edx);
   __ Pop(edi);
 
-  if (mode == InterpreterPushArgsMode::kWithFinalSpread) {
-    __ PopReturnAddressTo(ebx);
-    __ Pop(ecx);  // Pass the spread in a register
-    __ PushReturnAddressFrom(ebx);
-    __ sub(eax, Immediate(1));  // Subtract one for spread
-  } else {
-    __ AssertUndefinedOrAllocationSite(ebx);
-  }
+  // Call the appropriate constructor. Arguments are already in registers.
 
   if (mode == InterpreterPushArgsMode::kArrayFunction) {
-    // Tail call to the array construct stub (still in the caller
-    // context at this point).
+    // Tail call to the array construct stub (still in the caller context at
+    // this point).
+    __ AssertUndefinedOrAllocationSite(ebx);
     __ AssertFunction(edi);
     __ MoveForRootRegisterRefactoring(kJavaScriptCallExtraArg1Register, ebx);
     Handle<Code> code = BUILTIN_CODE(masm->isolate(), ArrayConstructorImpl);
     __ Jump(code, RelocInfo::CODE_TARGET);
   } else if (mode == InterpreterPushArgsMode::kWithFinalSpread) {
-    // Call the constructor with unmodified eax, edi, edx values.
+    __ PopReturnAddressTo(ebx);
+    __ Pop(ecx);  // Pass the spread in a register
+    __ PushReturnAddressFrom(ebx);
+    __ sub(eax, Immediate(1));  // Subtract one for spread
     __ Jump(BUILTIN_CODE(masm->isolate(), ConstructWithSpread),
             RelocInfo::CODE_TARGET);
   } else {
     DCHECK_EQ(InterpreterPushArgsMode::kOther, mode);
-    // Call the constructor with unmodified eax, edi, edx values.
+    __ AssertUndefinedOrAllocationSite(ebx);
     __ Jump(BUILTIN_CODE(masm->isolate(), Construct), RelocInfo::CODE_TARGET);
   }
 

src/ia32/interface-descriptors-ia32.cc

@@ -246,10 +246,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       eax,  // argument count (not including receiver)
-      edx,  // new target
-      edi,  // constructor
-      ebx,  // allocation site feedback
       ecx,  // address of first argument
+      edi,  // constructor to call
+      edx,  // new target
+      ebx,  // allocation site feedback if available, undefined otherwise
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/interface-descriptors.h

@@ -1004,13 +1004,13 @@ class InterpreterPushArgsThenCallDescriptor : public CallInterfaceDescriptor {
 class InterpreterPushArgsThenConstructDescriptor
     : public CallInterfaceDescriptor {
  public:
-  DEFINE_PARAMETERS(kNumberOfArguments, kNewTarget, kConstructor,
-                    kFeedbackElement, kFirstArgument)
+  DEFINE_PARAMETERS(kNumberOfArguments, kFirstArgument, kConstructor,
+                    kNewTarget, kFeedbackElement)
   DEFINE_PARAMETER_TYPES(MachineType::Int32(),      // kNumberOfArguments
-                         MachineType::AnyTagged(),  // kNewTarget
+                         MachineType::Pointer(),    // kFirstArgument
                          MachineType::AnyTagged(),  // kConstructor
-                         MachineType::AnyTagged(),  // kFeedbackElement
-                         MachineType::Pointer())    // kFirstArgument
+                         MachineType::AnyTagged(),  // kNewTarget
+                         MachineType::AnyTagged())  // kFeedbackElement
   DECLARE_DESCRIPTOR(InterpreterPushArgsThenConstructDescriptor,
                      CallInterfaceDescriptor)
 };

src/interpreter/interpreter-assembler.cc

@@ -1074,8 +1074,8 @@ Node* InterpreterAssembler::Construct(Node* target, Node* context,
         isolate(), InterpreterPushArgsMode::kArrayFunction);
     Node* code_target = HeapConstant(callable.code());
     var_result.Bind(CallStub(callable.descriptor(), code_target, context,
-                             args.reg_count(), new_target, target,
-                             var_site.value(), args.base_reg_location()));
+                             args.reg_count(), args.base_reg_location(), target,
+                             new_target, var_site.value()));
     Goto(&return_result);
   }
 
@@ -1087,8 +1087,8 @@ Node* InterpreterAssembler::Construct(Node* target, Node* context,
         isolate(), InterpreterPushArgsMode::kOther);
     Node* code_target = HeapConstant(callable.code());
     var_result.Bind(CallStub(callable.descriptor(), code_target, context,
-                             args.reg_count(), new_target, target,
-                             UndefinedConstant(), args.base_reg_location()));
+                             args.reg_count(), args.base_reg_location(), target,
+                             new_target, UndefinedConstant()));
     Goto(&return_result);
   }
 
@@ -1212,8 +1212,8 @@ Node* InterpreterAssembler::ConstructWithSpread(Node* target, Node* context,
       isolate(), InterpreterPushArgsMode::kWithFinalSpread);
   Node* code_target = HeapConstant(callable.code());
   return CallStub(callable.descriptor(), code_target, context, args.reg_count(),
-                  new_target, target, UndefinedConstant(),
-                  args.base_reg_location());
+                  args.base_reg_location(), target, new_target,
+                  UndefinedConstant());
 }
 
 Node* InterpreterAssembler::CallRuntimeN(Node* function_id, Node* context,

src/mips/interface-descriptors-mips.cc

@@ -238,10 +238,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       a0,  // argument count (not including receiver)
-      a3,  // new target
+      t4,  // address of the first argument
       a1,  // constructor to call
-      a2,  // allocation site feedback if available, undefined otherwise.
-      t4   // address of the first argument
+      a3,  // new target
+      a2,  // allocation site feedback if available, undefined otherwise
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/mips64/interface-descriptors-mips64.cc

@@ -238,10 +238,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       a0,  // argument count (not including receiver)
-      a3,  // new target
+      a4,  // address of the first argument
       a1,  // constructor to call
-      a2,  // allocation site feedback if available, undefined otherwise.
-      a4   // address of the first argument
+      a3,  // new target
+      a2,  // allocation site feedback if available, undefined otherwise
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/ppc/interface-descriptors-ppc.cc

@@ -238,10 +238,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       r3,  // argument count (not including receiver)
-      r6,  // new target
+      r7,  // address of the first argument
       r4,  // constructor to call
+      r6,  // new target
       r5,  // allocation site feedback if available, undefined otherwise
-      r7   // address of the first argument
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/s390/interface-descriptors-s390.cc

@@ -236,10 +236,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       r2,  // argument count (not including receiver)
-      r5,  // new target
+      r6,  // address of the first argument
       r3,  // constructor to call
+      r5,  // new target
       r4,  // allocation site feedback if available, undefined otherwise
-      r6   // address of the first argument
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/x64/interface-descriptors-x64.cc

@@ -239,10 +239,10 @@ void InterpreterPushArgsThenConstructDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
       rax,  // argument count (not including receiver)
+      rcx,  // address of first argument
+      rdi,  // constructor to call
       rdx,  // new target
-      rdi,  // constructor
       rbx,  // allocation site feedback if available, undefined otherwise
-      rcx,  // address of first argument
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }