Polynomial-time nested loop fusion with full parallelism

Sha, Edwin Hsing-Mean; Lang, Chenhua; Passos, N.L.

doi:10.1109/icpp.1996.538554

Cited by 8 publications

(13 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…12a. EX2, EX3, and EX4 refer to the DSP applications presented in [17] that have several loops, including WDF (Wave Digital filter), IIR (Infinite Impulse Response filter), DPCM (Differential Pulse-Code Modulation device), and 2D (Two Dimensional filter). EX5 and EX6 refer to the LDGs presented in [21].…”

Section: Simulation Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Loop Distribution and Fusion with Timing and Code Size Optimization

Liu

Sha

Zhuge

et al. 2010

J Sign Process Syst

View full text Add to dashboard Cite

In this paper, a technique that combines loop distribution with maximum direct loop fusion (LD_MDF) is proposed. The technique performs maximum loop distribution, followed by maximum direct loop fusion to optimize timing and code size simultaneously. The loop distribution theorems that state the conditions distributing any multi-level nested loop in the maximum way are proved. It is proved that the statements involved in the dependence cycle can be fully distributed if the summation of the edge weight of the dependence cycle satisfies a certain condition; otherwise, the statements should be put in the same loop after loop distribution. Based on the loop distribution theorems, algorithms are designed to conduct maximum loop distribution. The maximum direct loop fusion problem is mapped to the graph partitioning problem. A polynomial graph partitioning algorithm is developed to compute the fusion partitions. It is proved that the proposed maximum direct loop fusion algorithm produces the fewest number of resultant loop nests without violating dependence constraints. It is also shown that the resultant code size of the fused loops by the technique of loop distribution with maximum direct loop fusion is smaller than the code size of the original loops when the number of fused loops is less than the number of the original loops. The simulation results are presented to validate the proposed technique.

show abstract

Section: Simulation Resultsmentioning

confidence: 99%

“…People have found that various loop transformation techniques including loop fusion, loop distribution and loop interchanging could improve data locality and reduce the number of memory accesses so as to improve timing performance and reduce the energy consumption of data dominated applications [2,3,[13][14][15][16][17][18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Loop Distribution and Fusion with Timing and Code Size Optimization

Liu

Sha

Zhuge

et al. 2010

J Sign Process Syst

View full text Add to dashboard Cite

show abstract

“…LDG1, LDG2, and LDG3 refer to the examples presented in Figure 2, 8, and 17 in [6]. LDG4 and LDG5 refer to the examples shown in Figure 2(a) and Figure 6(a) in [4].…”

Section: Methodsmentioning

confidence: 99%

Loop Distribution and Fusion with Timing and Code Size Optimization for Embedded DSPs

Liu¹,

Zhuge²,

Shao

et al. 2005

Embedded and Ubiquitous Computing – EUC 2005

View full text Add to dashboard Cite

Abstract. Loop distribution and loop fusion are two effective loop transformation techniques to optimize the execution of the programs in DSP applications. In this paper, we propose a new technique combining loop distribution with direct loop fusion, which will improve the timing performance without jeopardizing the code size. We first develop the loop distribution theorems that state the legality conditions of loop distribution for multi-level nested loops. We show that if the summation of the edge weights of the dependence cycle satisfies a certain condition, then the statements involved in the dependence cycle can be distributed; otherwise, they should be put in the same loop after loop distribution. Then, we propose the technique of maximum loop distribution with direct loop fusion. The experimental results show that the execution time of the transformed loops by our technique is reduced 21.0% on average compared to the original loops and the code size of the transformed loops is reduced 7.0% on average compared to the original loops.

show abstract

“…Several valuable works have been proposed for loop fusion recently [19,9,17]. Loop shifting tries to compute loop index offsets for loop fusion.…”

Section: Introductionmentioning

confidence: 99%

General loop fusion technique for nested loops considering timing and code size

Liu

Zhuge

Shao

et al. 2004

Proceedings of the 2004 International Conference on Compilers, Architecture, and Synthesis for Embedded Systems

View full text Add to dashboard Cite

Loop fusion is commonly used to improve the instructionlevel parallelism of loops for high-performance embedded computing systems. Loop fusion, however, is not always directly applicable because the fusion prevention dependencies may exist among loops. Most of the existing techniques still have limitations in fully exploiting the advantages of loop fusion. In this paper, we present a general loop fusion technique for loops or nested loops based on the loop dependency graph model, retiming, and multi-dimensional retiming concepts. We show that any "J+K" model loop can be legally fused using our legalizing fusion technique. Polynomial-time algorithms are developed to solve the loop fusion problem for "J+K" model loops considering both timing and code size of the final code. Our technique produces the final code and calculates the resultant code size directly from the retiming values. The experimental results show that our loop fusion technique always significantly reduces the schedule length.

show abstract

Polynomial-time nested loop fusion with full parallelism

Cited by 8 publications

References 9 publications

Loop Distribution and Fusion with Timing and Code Size Optimization

Loop Distribution and Fusion with Timing and Code Size Optimization

Loop Distribution and Fusion with Timing and Code Size Optimization for Embedded DSPs

General loop fusion technique for nested loops considering timing and code size

Contact Info

Product

Resources

About