A method to reduce register overflow caused by fine-grained randomization security optimization

Abstract

The invention discloses a method for reducing register overflow caused by fine-grained randomization safety optimization, and relates to the technical field of compiler cycle optimization. First, the variables in the registers in the cycle body are reclassified, including cycle invariants, cycle induction variables and cycle changes. After the classification, the variables in the registers in the loop body are identified; finally, according to the number of loop invariants, loop induction variables, and loop variations in the loop body registers after identification, the loop expansion factor is obtained. The present invention proposes register pressure sensitive The loop unrolling method can improve the loop optimization effect to a certain extent and reduce the occurrence of register overflow; in addition, for randomization optimization, hot code, generally the loop body is more sensitive to the performance load brought by randomization, thus improving loop unrolling Optimizations can also improve the performance of fine-grained randomization security optimizations.

Description

technical field [0001] The invention relates to the technical field of compiler cycle optimization, in particular to a method for reducing register overflow caused by fine-grained randomization security optimization. Background technique [0002] There are two types of registers in the compilation optimization process, one is the hard register, which is the limited storage space actually used for storage in the processor, and the other is the virtual register, which is a virtual register resource proposed by the compilation process, and the number is much larger than The actual number of registers. Register pressure refers to the number of hard registers required to store all active pseudo-register values ​​​​at a certain program point during compilation, and the register pressure of a basic block, loop or function refers to registers at all program points in the code block maximum pressure. Register overflow is a situation where excess memory access is caused by excessive...

AI Technical Summary

Problems solved by technology

The existing loop unrolling optimization does not take register pressure into account, but only estimates according to heuristic rules, because to a certain extent, it will lead to excessive register pressure and register overflow.

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