摘要:
A method, system, and computer program product for performing register promotion, that optimizes placement of load and store operations of a computer program within a compiler. Based on the observation that the circumstances for promoting a memory location's value to register coincide with situations where the program exhibits partial redundancy between accesses to the memory location, the system is an approach to register promotion that models the optimization as two separate problems: (1) the partial redundancy elimination (PRE) of loads and (2) the PRE of stores. Both of these problems are solved through a sparse approach to PRE. The static single assignment PRE (SSAPRE) method for eliminating partial redundancy using a sparse SSA representation representations the foundation in eliminating redundancy among memory accesses, enabling the achievement of both computational and live range optimality in register promotion results. A static single use (SSU) representation is defined allowing the dual of the SSAPRE algorithm, called SSUPRE, to perform the partial redundancy elimination of stores. SSUPRE is performed after the PRE of loads, taking advantage of the loads' having been converted into pseudo-register references so that there are fewer barriers to the movement of stores. Consequently, the compiler produces more efficient, register-promoted executable program code from the SSA representation.
摘要:
A method, system, and computer product uses a hashed static single assignment (SSA) form as a program representation and a medium for performing global scalar optimization. A compiler, after expressing the computer program in SSA form, can perform one or more static single assignment (SSA)-based, SSA-preserving global scalar optimization procedures on the SSA representation. Such a procedure modifies, (i.e., optimizes) the SSA representation of the program while preserving the utility of its embedded use-deprogram information for purposes of subsequent SSA-based, SSA-preserving global scalar optimizations. This saves the overhead expense of having to explicitly regenerate use-def program information for successive SSA-based, SSA-preserving global scalar optimizations.
摘要:
Partial redundancy elimination of a computer program is described that operates using a static single assignment (SSA) representation of a computer program. The SSA representation of the computer program is processed to eliminate partially redundant expressions in the computer program. This processing involves inserting .PHI. functions for expressions where different values of the expressions reach common points in the computer program. A result of each of the .PHI. functions is stored in a hypothetical variable h. The processing also involves a renaming step where SSA versions are assigned to hypothetical variables h in the computer program, a down safety step of determining whether each .PHI. function in the computer program is down safe, and a will be available step of determining whether each expression in the computer program will be available at each .PHI. function following eventual insertion of code into the computer program for purposes of partial redundancy elimination. The processing also includes a finalize step of transforming the SSA representation of the computer program having hypothetical variables h to a SSA graph that includes some insertion information reflecting eventual insertions of code into the computer program for purposes of partial redundancy elimination, and a code motion step of updating the SSA graph based on the insertion information to introduce real temporary variables t for the hypothetical variables h.
摘要:
Systems and methods for implementing network changes are described herein. In one aspect, a network change procedure may be comprised of a plurality of scripts that may implement a change in the network. In one embodiment, the deployment may be paused after the script has been executed. During the pause, a change management server may determine the impact of the change on the network. If the change had a positive effect, the change management server may execute another script to make another network change. However, if the change had a negative effect, the change management server may initiate one or more remedial actions.
摘要:
Methods, wires, and apparatus for use in cutting (e.g., slicing) hard, brittle materials is provided. The wire can be a super-abrasive wire that includes a wire core and super-abrasive particles bonded to the wire core via a metal bonding layer. This wire, or another type of wire, can be used to slice workpieces useful for producing wafers. The workpieces can be aligned within a holder to produce wafers using the device and methods presently provided. The holder rotates about its central axis, which translates to workpieces moving in orbit around this axis. A single abrasive wire, or multiple turns of wire stretched tightly between wire guides, is then contacted with the rotating holder to slice the workpieces.
摘要:
Novel imidazoles and novel pyrroles are provided. Also provided are pharmaceutical compositions, methods of making and methods of using the compounds.
摘要:
A mechanical device to be cooperatively associated with a computer mouse to cause proper positioning of a user's hand and wrist when using the mouse. The device comprises a support surface to be positioned both longitudinally and height-wise with respect to the mouse so as to support the heel of the user's hand so that the user's hand and wrist are in an ergonomically correct position relative to each other during use of the mouse.
摘要:
Novel imidazoles are provided. The compounds are useful as HMGCo-A Reductase Inhibitor. Also provided are pharmaceutical compositions of the compounds. Methods of making and methods of using the compounds are also provided.
摘要:
A seat belt restraint lock for children is disclosed, comprised of an improved female receptacle for a motor vehicle seat belt buckle. The female receptacle consists of a main body, of a generally rectangular, box configuration. A plate located on the top surface of the main body covers the traditional release button. The plate can only be opened by compressing two locking cylinders located on the lateral sides of the main body. The locking cylinders possess spring tension to ensure that a child cannot open the plate.
摘要:
A separation chamber comprising a solid walled container vessel having a removably sealable top which contains an inlet port, the chamber having an inner perforated screen wall with an outlet port positioned in the side of the vessel extending into the interior of the perforated screen inner wall, a static vacuum line communicating with the outlet line and the annular space between the solid outer container wall and the inner perforated screen wall, and a self-contained disposal bag having an inlet sleeve and an outlet sleeve, said bag design to conform to the contours of the inner perforated screen wall and said inlet sleeve for extending through the inlet port and the outlet sleeve for extending outwardly through said outlet port, both sleeves having a means for securing the sleeves in a closed and secure position once the disposal bag has become filled with particulate matter, the bag, complying with disposal requirements, then being deposited in an appropriate disposal area.