| // Copyright (c) 2019, 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. |
| |
| #ifndef RUNTIME_VM_FRAME_LAYOUT_H_ |
| #define RUNTIME_VM_FRAME_LAYOUT_H_ |
| |
| #include "platform/assert.h" |
| #include "platform/globals.h" |
| |
| // FrameLayout structure captures configuration specific properties of the |
| // frame layout used by the runtime system and compiler. |
| // |
| // Runtime system uses runtime_frame_layout defined in stack_frame.h. |
| // Compiler uses compiler::target::frame_layout defined in runtime_api.h |
| |
| namespace dart { |
| |
| // Forward declarations. |
| class LocalVariable; |
| |
| struct FrameLayout { |
| // The offset (in words) from FP to the first object. |
| intptr_t first_object_from_fp; |
| |
| // The offset (in words) from FP to the last fixed object. |
| intptr_t last_fixed_object_from_fp; |
| |
| // The offset (in words) from FP to the slot past the last parameter. |
| intptr_t param_end_from_fp; |
| |
| // The offset (in words) from SP on entry (before frame is setup) to |
| // the last parameter. |
| intptr_t last_param_from_entry_sp; |
| |
| // The offset (in words) from FP to the first local. |
| intptr_t first_local_from_fp; |
| |
| // The fixed size of the frame. |
| intptr_t dart_fixed_frame_size; |
| |
| // The offset (in words) from FP to the saved pool (if applicable). |
| intptr_t saved_caller_pp_from_fp; |
| |
| // The offset (in words) from FP to the saved FP. |
| intptr_t saved_caller_fp_from_fp; |
| |
| // The offset (in words) from FP to the saved return address. |
| intptr_t saved_caller_pc_from_fp; |
| |
| // The offset (in words) from FP to the code object (if applicable). |
| intptr_t code_from_fp; |
| |
| // Entry and exit frame layout. |
| intptr_t exit_link_slot_from_entry_fp; |
| |
| // The number of fixed slots below the saved PC. |
| intptr_t saved_below_pc() const { return -first_local_from_fp; } |
| |
| // Returns the FP-relative index where [variable] can be found (assumes |
| // [variable] is not captured), in words. |
| intptr_t FrameSlotForVariable(const LocalVariable* variable) const; |
| |
| // Returns the FP-relative index where [variable_index] can be found (assumes |
| // [variable_index] comes from a [LocalVariable::index()], which is not |
| // captured). |
| intptr_t FrameSlotForVariableIndex(intptr_t index) const; |
| |
| // Returns the variable index from a FP-relative index. |
| intptr_t VariableIndexForFrameSlot(intptr_t frame_slot) const { |
| if (frame_slot <= first_local_from_fp) { |
| return frame_slot - first_local_from_fp; |
| } else { |
| ASSERT(frame_slot > param_end_from_fp); |
| return frame_slot - param_end_from_fp; |
| } |
| } |
| |
| // Called to initialize the stack frame layout during startup. |
| static void Init(); |
| }; |
| |
| } // namespace dart |
| |
| #endif // RUNTIME_VM_FRAME_LAYOUT_H_ |