ScEpTIC.AST.transformations.virtual_memory.analysis package

Submodules

ScEpTIC.AST.transformations.virtual_memory.analysis.memory_instructions_indentifier module

class ScEpTIC.AST.transformations.virtual_memory.analysis.memory_instructions_indentifier.MemoryInstructionsIdentifier

Bases: object

This class contains the analysis required for identifying the first/last memory read/write instructions.

static resolve_first_reads_writes(basic_blocks, only_nvm=False, conditional_container=None, conditional_path=None)
Analyses the provided sequence of basic blocks and returns:

  • the list of all the read instructions that can execute before any write

  • the list of all the write instructions that can execute as first

Each list is a python dictionary, whose key is the memory tag

static resolve_last_reads_writes(basic_blocks, only_nvm=False, conditional_container=None, conditional_path=None)
Analyses the provided sequence of basic blocks and returns:

  • the list of all the read instructions that can execute after any write

  • the list of all the write instructions that can execute as last

Each list is a python dictionary, whose key is the memory tag

ScEpTIC.AST.transformations.virtual_memory.analysis.memory_usage module

class ScEpTIC.AST.transformations.virtual_memory.analysis.memory_usage.MemoryUsage

Bases: object

static get_base_memory_tag(memory_tag)

Returns the base memory tag, that is, a scalar-equivalent memory tag e.g. a[0] -> returns a[]

static get_memory_usage_list(computation_intervals, order_function, initial_alive_tags)

Analyses the memory tags that need to be preserved across power failures :returns:

  • set of the tags that the function gets from outside its stack frame

  • set of the tags that the function writes outside its stack frame

  • list of the tags that need to be preserved, for each computation interval

Outside-frame accesses supported only for global variables. TODO: pointers (not required for evaluation)

static get_outside_frame_read_volatile(before_call_data, outside_frame_reads)

Computes the elements that need to be retrieved from volatile memory

static get_unique_volatile_elements(volatile_elements, merge_data={})

Merges volatile_elements and merge_data Parses retrieved volatile data and returns unique sets for each function

static get_volatile_elements_after_calls(computation_intervals, order_function, checkpoint_function_name)

Returns for each function the memory tags whose store can target volatile memory Does not support call depth > 1 (sufficient for evaluation) TODO: support call depth > 1

static get_volatile_elements_before_calls(computation_intervals, order_function, checkpoint_function_name)

Returns for each function the memory tags whose reads can target volatile memory Does not support call depth > 1 (sufficient for evaluation) TODO: support call depth > 1

static remove_after_call_data_from_outside_frame_writes(after_call_data, outside_frame_writes)

Computes the elements that need to be preserved by the function call that has only one computation interval. The method returns a list of sets (one set per call to the function)

ScEpTIC.AST.transformations.virtual_memory.analysis.nvm_instructions_identifier module

class ScEpTIC.AST.transformations.virtual_memory.analysis.nvm_instructions_identifier.NVMInstructionsIdentifier

Bases: object

Class for identifying specific sets of NVM read/write instructions

static already_processed(metadata)

Returns if the metadata has already been processed due to instructions included in previous instructions

static identify_nvm_instruction(basic_blocks, conditional_container=None, conditional_path=None)

Identifies all the NVM read/write instructions in basic_block

static identify_nvm_instructions_to_consolidate(metadata, n_min_function)

ScEpTIC.AST.transformations.virtual_memory.analysis.registers_usage module

class ScEpTIC.AST.transformations.virtual_memory.analysis.registers_usage.RegistersUsage

Bases: object

static account_for_pc_save_only(comp_int_manager, name)

Adjust checkpoints that need to save the stack pointer (that is, if a checkpoint need to save a register, except PC) If a checkpoint need to save only the PC (that is, checkpoint_save_esp = False) -> no 2-phase-commit needed as PC save is atomic

static get_alloca_regs(computation_intervals, n_args)

Returns the registers that are target of alloca instructions

static get_regs_first_use_def(basic_blocks, alloca_regs)
Returns two lists:

  • registers whose use happens before their defs

  • registers defined

static reset_register_info(comp_int_manager, name)

Resets the register-saving information associated to each checkpoint

static set_checkpoints_esp_reg(comp_int_manager, name)

Sets the checkpoints in the computation interval that need to save the stack pointer

static set_checkpoints_general_purpose_regs(comp_int_manager, name)

Sets the general purpose registers that each checkpoint in the computation interval need to save

static set_checkpoints_regs(comp_int_manager)

Identifies the registers that each checkpoint need to save

Module contents