Introduce a class encapsulating arguments descriptor arrays.

runtime/vm/stub_code_x64.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/assembler_macros.h"
 #include "vm/compiler.h"
+#include "vm/dart_entry.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/instructions.h"
 #include "vm/object_store.h"
 #include "vm/pages.h"
 #include "vm/resolver.h"
 #include "vm/scavenger.h"
 #include "vm/stub_code.h"
 
 
 #define __ assembler->
@@ skipping 154 matching lines @@
 
   // Cache Context pointer into CTX while executing Dart code.
   __ movq(CTX, R8);
 
   __ LeaveFrame();
   __ ret();
 }
 
 
 // Input parameters:
-//   R10: arguments descriptor array (num_args is first Smi element).
+//   R10: arguments descriptor array.
 void StubCode::GenerateCallStaticFunctionStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   AssemblerMacros::EnterStubFrame(assembler);
   __ pushq(R10);  // Preserve arguments descriptor array.
   __ pushq(raw_null);  // Setup space on stack for return value.
   __ CallRuntime(kPatchStaticCallRuntimeEntry);
   __ popq(RAX);  // Get Code object result.
   __ popq(R10);  // Restore arguments descriptor array.
   // Remove the stub frame as we are about to jump to the dart function.
   __ LeaveFrame();
 
   __ movq(RBX, FieldAddress(RAX, Code::instructions_offset()));
   __ addq(RBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ jmp(RBX);
 }
 
 
 // Called from a static call only when an invalid code has been entered
 // (invalid because its function was optimized or deoptimized).
-// R10: arguments descriptor array (num_args is first Smi element).
+// R10: arguments descriptor array.
 void StubCode::GenerateFixCallersTargetStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   AssemblerMacros::EnterStubFrame(assembler);
   __ pushq(R10);  // Preserve arguments descriptor array.
   __ pushq(raw_null);  // Setup space on stack for return value.
   __ CallRuntime(kFixCallersTargetRuntimeEntry);
   __ popq(RAX);  // Get Code object.
   __ popq(R10);  // Restore arguments descriptor array.
   __ movq(RAX, FieldAddress(RAX, Code::instructions_offset()));
@@ skipping 29 matching lines @@
   __ AddImmediate(RBX, Immediate(kWordSize));
   __ AddImmediate(R12, Immediate(-kWordSize));
   __ Bind(&loop_condition);
   __ decq(R10);
   __ j(POSITIVE, &loop, Assembler::kNearJump);
 }
 
 
 // Input parameters:
 //   RBX: ic-data.
-//   R10: arguments descriptor array (num_args is first Smi element).
+//   R10: arguments descriptor array.
 // Note: The receiver object is the first argument to the function being
 //       called, the stub accesses the receiver from this location directly
 //       when trying to resolve the call.
 void StubCode::GenerateInstanceFunctionLookupStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
 
   // Create a stub frame as we are pushing some objects on the stack before
   // calling into the runtime.
   AssemblerMacros::EnterStubFrame(assembler);
 
   // Preserve values across call to resolving.
   // Stack at this point:
   // TOS + 0: PC marker => RawInstruction object.
   // TOS + 1: Saved RBP of previous frame. <== RBP
   // TOS + 2: Dart code return address
   // TOS + 3: Last argument of caller.
   // ....
-  // Total number of args is the first Smi in args descriptor array (R10).
-  __ movq(RAX, FieldAddress(R10, Array::data_offset()));
+  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ movq(RAX, Address(RBP, RAX, TIMES_4, kWordSize));  // Get receiver.
   __ pushq(R10);  // Preserve arguments descriptor array.
   __ pushq(RAX);  // Preserve receiver.
   __ pushq(RBX);  // Preserve ic-data.
   // First resolve the function to get the function object.
 
   __ pushq(raw_null);  // Setup space on stack for return value.
   __ pushq(RAX);  // Push receiver.
   __ CallRuntime(kResolveCompileInstanceFunctionRuntimeEntry);
   __ popq(RAX);  // Remove receiver pushed earlier.
@@ skipping 78 matching lines @@
 
   __ cmpq(RBX, raw_null);
   Label function_not_found;
   __ j(EQUAL, &function_not_found);
 
   // RBX: Closure object.
   // R13: Arguments descriptor array.
   __ pushq(raw_null);  // Setup space on stack for result from invoking Closure.
   __ pushq(RBX);  // Closure object.
   __ pushq(R13);  // Arguments descriptor.
-  __ movq(R13, FieldAddress(R13, Array::data_offset()));
+  __ movq(R13, FieldAddress(R13, ArgumentsDescriptor::count_offset()));
   __ SmiUntag(R13);
   __ subq(R13, Immediate(1));  // Arguments array length, minus the receiver.
   PushArgumentsArray(assembler, (kWordSize * 6));
   // Stack layout explaining "(kWordSize * 6)" offset.
   // TOS + 0: Argument array.
   // TOS + 1: Arguments descriptor array.
   // TOS + 2: Closure object.
   // TOS + 3: Place for result from closure function.
   // TOS + 4: PC marker => RawInstruction object.
   // TOS + 5: Saved RBP of previous frame. <== RBP
@@ skipping 11 matching lines @@
   // Remove the stub frame as we are about to return.
   __ LeaveFrame();
   __ ret();
 
   __ Bind(&function_not_found);
   // The target function was not found, so invoke method
   // "void noSuchMethod(function_name, args_array)".
   //   RAX: receiver.
   //   R10: ic-data.
   //   RBX: raw_null.
-  //   R13: argument descriptor array.
+  //   R13: arguments descriptor array.
 
   __ pushq(raw_null);  // Setup space on stack for result from noSuchMethod.
   __ pushq(RAX);  // Receiver.
   __ pushq(R10);  // IC-data array.
-  __ pushq(R13);  // Argument descriptor array.
-  __ movq(R13, FieldAddress(R13, Array::data_offset()));
+  __ pushq(R13);  // Arguments descriptor array.
+  __ movq(R13, FieldAddress(R13, ArgumentsDescriptor::count_offset()));
   __ SmiUntag(R13);
   __ subq(R13, Immediate(1));  // Arguments array length, minus the receiver.
   // See stack layout below explaining "wordSize * 7" offset.
   PushArgumentsArray(assembler, (kWordSize * 7));
 
   // Stack:
-  // TOS + 0: Argument array.
-  // TOS + 1: Argument descriptor array.
+  // TOS + 0: Arguments array.
+  // TOS + 1: Arguments descriptor array.
   // TOS + 2: IC-data array.
   // TOS + 3: Receiver.
   // TOS + 4: Place for result from noSuchMethod.
   // TOS + 5: PC marker => RawInstruction object.
   // TOS + 6: Saved RBP of previous frame. <== RBP
   // TOS + 7: Dart code return address
   // TOS + 8: Last argument of caller.
   // ....
 
   __ CallRuntime(kInvokeNoSuchMethodFunctionRuntimeEntry);
@@ skipping 251 matching lines @@
   __ CallRuntime(kAllocateArrayRuntimeEntry);
   __ popq(RAX);  // Pop element type argument.
   __ popq(R10);  // Pop array length argument.
   __ popq(RAX);  // Pop return value from return slot.
   __ LeaveFrame();
   __ ret();
 }
 
 
 // Input parameters:
-//   R10: Arguments descriptor array (num_args is first Smi element, closure
-//        object is included in num_args and is first argument).
+//   R10: Arguments descriptor array.
 // Note: The closure object is the first argument to the function being
 //       called, the stub accesses the closure from this location directly
 //       when trying to resolve the call.
 void StubCode::GenerateCallClosureFunctionStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
 
-  // Total number of args is the first Smi in args descriptor array (R10).
-  __ movq(RAX, FieldAddress(R10, Array::data_offset()));  // Load num_args.
+  // Load num_args.
+  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   // Load closure object in R13.
   __ movq(R13, Address(RSP, RAX, TIMES_4, 0));  // RAX is a Smi.
 
   // Verify that R13 is a closure by checking its class.
   Label not_closure;
   __ cmpq(R13, raw_null);
   // Not a closure, but null object.
   __ j(EQUAL, &not_closure);
   __ testq(R13, Immediate(kSmiTagMask));
   __ j(ZERO, &not_closure);  // Not a closure, but a smi.
@@ skipping 28 matching lines @@
   __ popq(R10);  // Restore arguments descriptor array.
   // Restore RAX.
   __ movq(RAX, FieldAddress(RBX, Function::code_offset()));
 
   // Remove the stub frame as we are about to jump to the closure function.
   __ LeaveFrame();
 
   __ Bind(&function_compiled);
   // RAX: Code.
   // RBX: Function.
-  // R10: Arguments descriptor array (num_args is first Smi element).
+  // R10: Arguments descriptor array.
 
   __ movq(RBX, FieldAddress(RAX, Code::instructions_offset()));
   __ addq(RBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ jmp(RBX);
 
   __ Bind(&not_closure);
   // Call runtime to report that a closure call was attempted on a non-closure
   // object, passing the non-closure object and its arguments array.
   // R13: non-closure object.
-  // R10: arguments descriptor array (num_args is first Smi element, closure
-  //      object is included in num_args).
+  // R10: arguments descriptor array.
 
   // Create a stub frame as we are pushing some objects on the stack before
   // calling into the runtime.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushq(raw_null);  // Setup space on stack for result from error reporting.
   __ pushq(R13);  // Non-closure object.
-    // Total number of args is the first Smi in args descriptor array (R10).
-  __ movq(R13, FieldAddress(R10, Array::data_offset()));  // Load num_args.
+  // Load num_args.
+  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ SmiUntag(R13);
   __ subq(R13, Immediate(1));  // Arguments array length, minus the closure.
   // See stack layout below explaining "wordSize * 5" offset.
   PushArgumentsArray(assembler, (kWordSize * 5));
 
   // Stack:
   // TOS + 0: Argument array.
   // TOS + 1: Non-closure object.
   // TOS + 2: Place for result from reporting the error.
   // TOS + 3: PC marker => RawInstruction object.
@@ skipping 55 matching lines @@
   // Note that VisitObjectPointers will find this saved Context pointer during
   // GC marking, since it traverses any information between SP and
   // FP - kExitLinkOffsetInEntryFrame.
   __ movq(RAX, Address(R8, Isolate::top_context_offset()));
   __ pushq(RAX);
 
   // Load arguments descriptor array into R10, which is passed to Dart code.
   __ movq(R10, Address(RSI, VMHandles::kOffsetOfRawPtrInHandle));
 
   // Load number of arguments into RBX.
-  __ movq(RBX, FieldAddress(R10, Array::data_offset()));
+  __ movq(RBX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ SmiUntag(RBX);
 
   // Set up arguments for the Dart call.
   Label push_arguments;
   Label done_push_arguments;
   __ testq(RBX, RBX);  // check if there are arguments.
   __ j(ZERO, &done_push_arguments, Assembler::kNearJump);
   __ movq(RAX, Immediate(0));
   __ Bind(&push_arguments);
   __ movq(RCX, Address(RDX, RAX, TIMES_8, 0));  // RDX is start of arguments.
   __ movq(RCX, Address(RCX, VMHandles::kOffsetOfRawPtrInHandle));
   __ pushq(RCX);
   __ incq(RAX);
   __ cmpq(RAX, RBX);
   __ j(LESS, &push_arguments, Assembler::kNearJump);
   __ Bind(&done_push_arguments);
 
   // Call the Dart code entrypoint.
   __ call(RDI);  // R10 is the arguments descriptor array.
 
   // Read the saved new Context pointer.
   __ movq(CTX, Address(RBP, kNewContextOffset));
   __ movq(CTX, Address(CTX, VMHandles::kOffsetOfRawPtrInHandle));
 
   // Read the saved arguments descriptor array to obtain the number of passed
-  // arguments, which is the first element of the array, a Smi.
+  // arguments.
   __ movq(RSI, Address(RBP, kArgumentsDescOffset));
   __ movq(R10, Address(RSI, VMHandles::kOffsetOfRawPtrInHandle));
-  __ movq(RDX, FieldAddress(R10, Array::data_offset()));
+  __ movq(RDX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   // Get rid of arguments pushed on the stack.
   __ leaq(RSP, Address(RSP, RDX, TIMES_4, 0));  // RDX is a Smi.
 
   // Load Isolate pointer from Context structure into CTX. Drop Context.
   __ movq(CTX, FieldAddress(CTX, Context::isolate_offset()));
 
   // Restore the saved Context pointer into the Isolate structure.
   // Uses RCX as a temporary register for this.
   __ popq(RCX);
   __ movq(Address(CTX, Isolate::top_context_offset()), RCX);
@@ skipping 536 matching lines @@
 void StubCode::GenerateCallNoSuchMethodFunctionStub(Assembler* assembler) {
   // The target function was not found, so invoke method
   // "void noSuchMethod(function_name, Array arguments)".
   // TODO(regis): For now, we simply pass the actual arguments, both positional
   // and named, as the argument array. This is not correct if out-of-order
   // named arguments were passed.
   // The signature of the "noSuchMethod" method has to change from
   // noSuchMethod(String name, Array arguments) to something like
   // noSuchMethod(InvocationMirror call).
   // Also, the class NoSuchMethodError has to be modified accordingly.
-  // Total number of args is the first Smi in args descriptor array (R10).
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
-  __ movq(R13, FieldAddress(R10, Array::data_offset()));
+  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ SmiUntag(R13);
   __ movq(RAX, Address(RBP, R13, TIMES_8, kWordSize));  // Get receiver.
 
   // Create a stub frame.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushq(raw_null);  // Setup space on stack for result from noSuchMethod.
   __ pushq(RAX);  // Receiver.
   __ pushq(RBX);  // IC data array.
   __ pushq(R10);  // Arguments descriptor array.
@@ skipping 114 matching lines @@
 
   // Loop that checks if there is an IC data match.
   Label loop, update, test, found, get_class_id_as_smi;
   // RBX: IC data object (preserved).
   __ movq(R12, FieldAddress(RBX, ICData::ic_data_offset()));
   // R12: ic_data_array with check entries: classes and target functions.
   __ leaq(R12, FieldAddress(R12, Array::data_offset()));
   // R12: points directly to the first ic data array element.
 
   // Get the receiver's class ID (first read number of arguments from
-  // argument descriptor array and then access the receiver from the stack).
-  __ movq(RAX, FieldAddress(R10, Array::data_offset()));
+  // arguments descriptor array and then access the receiver from the stack).
+  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ movq(RAX, Address(RSP, RAX, TIMES_4, 0));  // RAX (argument count) is Smi.
   __ call(&get_class_id_as_smi);
   // RAX: receiver's class ID as smi.
   __ movq(R13, Address(R12, 0));  // First class ID (Smi) to check.
   __ jmp(&test);
 
   __ Bind(&loop);
   for (int i = 0; i < num_args; i++) {
     if (i > 0) {
       // If not the first, load the next argument's class ID.
-      __ movq(RAX, FieldAddress(R10, Array::data_offset()));
+      __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
       __ movq(RAX, Address(RSP, RAX, TIMES_4, - i * kWordSize));
       __ call(&get_class_id_as_smi);
       // RAX: next argument class ID (smi).
       __ movq(R13, Address(R12, i * kWordSize));
       // R13: next class ID to check (smi).
     }
     __ cmpq(RAX, R13);  // Class id match?
     if (i < (num_args - 1)) {
       __ j(NOT_EQUAL, &update);  // Continue.
     } else {
       // Last check, all checks before matched.
       __ j(EQUAL, &found);  // Break.
     }
   }
   __ Bind(&update);
   // Reload receiver class ID.  It has not been destroyed when num_args == 1.
   if (num_args > 1) {
-    __ movq(RAX, FieldAddress(R10, Array::data_offset()));
+    __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
     __ movq(RAX, Address(RSP, RAX, TIMES_4, 0));
     __ call(&get_class_id_as_smi);
   }
 
   const intptr_t entry_size = ICData::TestEntryLengthFor(num_args) * kWordSize;
   __ addq(R12, Immediate(entry_size));  // Next entry.
   __ movq(R13, Address(R12, 0));  // Next class ID.
 
   __ Bind(&test);
   __ cmpq(R13, Immediate(Smi::RawValue(kIllegalCid)));  // Done?
   __ j(NOT_EQUAL, &loop, Assembler::kNearJump);
 
   // IC miss.
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   // Compute address of arguments (first read number of arguments from
-  // argument descriptor array and then compute address on the stack).
-  __ movq(RAX, FieldAddress(R10, Array::data_offset()));
+  // arguments descriptor array and then compute address on the stack).
+  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   __ leaq(RAX, Address(RSP, RAX, TIMES_4, 0));  // RAX is Smi.
   AssemblerMacros::EnterStubFrame(assembler);
-  __ pushq(R10);  // Preserve arguments array.
+  __ pushq(R10);  // Preserve arguments descriptor array.
   __ pushq(RBX);  // Preserve IC data array
   __ pushq(raw_null);  // Setup space on stack for result (target code object).
   // Push call arguments.
   for (intptr_t i = 0; i < num_args; i++) {
     __ movq(R10, Address(RAX, -kWordSize * i));
     __ pushq(R10);
   }
   if (num_args == 1) {
     __ CallRuntime(kInlineCacheMissHandlerOneArgRuntimeEntry);
   } else if (num_args == 2) {
     __ CallRuntime(kInlineCacheMissHandlerTwoArgsRuntimeEntry);
   } else if (num_args == 3) {
     __ CallRuntime(kInlineCacheMissHandlerThreeArgsRuntimeEntry);
   } else {
     UNIMPLEMENTED();
   }
   // Remove call arguments pushed earlier.
   for (intptr_t i = 0; i < num_args; i++) {
     __ popq(RAX);
   }
   __ popq(RAX);  // Pop returned code object into RAX (null if not found).
   __ popq(RBX);  // Restore IC data array.
-  __ popq(R10);  // Restore arguments array.
+  __ popq(R10);  // Restore arguments descriptor array.
   __ LeaveFrame();
   Label call_target_function;
   __ cmpq(RAX, raw_null);
   __ j(NOT_EQUAL, &call_target_function, Assembler::kNearJump);
   // NoSuchMethod or closure.
   // Mark IC call that it may be a closure call that does not collect
   // type feedback.
   __ movb(FieldAddress(RBX, ICData::is_closure_call_offset()), Immediate(1));
   __ jmp(&StubCode::InstanceFunctionLookupLabel());
 
@@ skipping 25 matching lines @@
   __ Bind(&not_smi);
   __ LoadClassId(RAX, RAX);
   __ SmiTag(RAX);
   __ ret();
 }
 
 
 // Use inline cache data array to invoke the target or continue in inline
 // cache miss handler. Stub for 1-argument check (receiver class).
 //  RBX: Inline cache data object.
-//  RDX: Arguments array.
+//  R10: Arguments descriptor array.
 //  TOS(0): Return address.
 // Inline cache data object structure:
 // 0: function-name
 // 1: N, number of arguments checked.
 // 2 .. (length - 1): group of checks, each check containing:
 //   - N classes.
 //   - 1 target function.
 void StubCode::GenerateOneArgCheckInlineCacheStub(Assembler* assembler) {
   GenerateUsageCounterIncrement(assembler, RCX);
   GenerateNArgsCheckInlineCacheStub(assembler, 1);
 }
 
 
 void StubCode::GenerateTwoArgsCheckInlineCacheStub(Assembler* assembler) {
   GenerateUsageCounterIncrement(assembler, RCX);
   GenerateNArgsCheckInlineCacheStub(assembler, 2);
 }
 
 
 void StubCode::GenerateThreeArgsCheckInlineCacheStub(Assembler* assembler) {
   GenerateUsageCounterIncrement(assembler, RCX);
   GenerateNArgsCheckInlineCacheStub(assembler, 3);
 }
 
 // Use inline cache data array to invoke the target or continue in inline
 // cache miss handler. Stub for 1-argument check (receiver class).
 //  RDI: function which counter needs to be incremented.
 //  RBX: Inline cache data object.
-//  RDX: Arguments array.
+//  R10: Arguments descriptor array.
 //  TOS(0): Return address.
 // Inline cache data object structure:
 // 0: function-name
 // 1: N, number of arguments checked.
 // 2 .. (length - 1): group of checks, each check containing:
 //   - N classes.
 //   - 1 target function.
 void StubCode::GenerateOneArgOptimizedCheckInlineCacheStub(
     Assembler* assembler) {
   GenerateOptimizedUsageCounterIncrement(assembler);
@@ skipping 20 matching lines @@
   GenerateNArgsCheckInlineCacheStub(assembler, 1);
 }
 
 
 // Megamorphic call is currently implemented as IC call but through a stub
 // that does not check/count function invocations.
 void StubCode::GenerateMegamorphicCallStub(Assembler* assembler) {
   GenerateNArgsCheckInlineCacheStub(assembler, 1);
 }
 
-//  R10: Arguments array.
+//  R10: Arguments descriptor array.
 //  TOS(0): return address (Dart code).
 void StubCode::GenerateBreakpointStaticStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   AssemblerMacros::EnterStubFrame(assembler);
   __ pushq(R10);  // Preserve arguments descriptor.
   __ pushq(raw_null);  // Room for result.
   __ CallRuntime(kBreakpointStaticHandlerRuntimeEntry);
   __ popq(RAX);  // Code object.
   __ popq(R10);  // Restore arguments descriptor.
@@ skipping 15 matching lines @@
   __ popq(RAX);
   __ LeaveFrame();
 
   __ popq(R11);  // discard return address of call to this stub.
   __ LeaveFrame();
   __ ret();
 }
 
 
 //  RBX: Inline cache data array.
-//  R10: Arguments array.
+//  R10: Arguments descriptor array.
 //  TOS(0): return address (Dart code).
 void StubCode::GenerateBreakpointDynamicStub(Assembler* assembler) {
   AssemblerMacros::EnterStubFrame(assembler);
   __ pushq(RBX);
   __ pushq(R10);
   __ CallRuntime(kBreakpointDynamicHandlerRuntimeEntry);
   __ popq(R10);
   __ popq(RBX);
   __ LeaveFrame();
 
@@ skipping 354 matching lines @@
   __ cmpq(left, right);
   __ Bind(&done);
   __ popq(right);
   __ popq(left);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64