Toward real-time performance benchmarks for Ada
Communications of the ACM
A portable global optimizer and linker
PLDI '88 Proceedings of the ACM SIGPLAN 1988 conference on Programming Language design and Implementation
Predicting conditional branch directions from previous runs of a program
ASPLOS V Proceedings of the fifth international conference on Architectural support for programming languages and operating systems
Improving the accuracy of static branch prediction using branch correlation
ASPLOS VI Proceedings of the sixth international conference on Architectural support for programming languages and operating systems
Reducing branch costs via branch alignment
ASPLOS VI Proceedings of the sixth international conference on Architectural support for programming languages and operating systems
Avoiding conditional branches by code replication
PLDI '95 Proceedings of the ACM SIGPLAN 1995 conference on Programming language design and implementation
Interprocedural conditional branch elimination
Proceedings of the ACM SIGPLAN 1997 conference on Programming language design and implementation
Near-optimal intraprocedural branch alignment
Proceedings of the ACM SIGPLAN 1997 conference on Programming language design and implementation
Coalescing Conditional Branches into Efficient Indirect Jumps
SAS '97 Proceedings of the 4th International Symposium on Static Analysis
Aggressive Loop Unrolling in a Retargetable Optimizing Compiler
CC '96 Proceedings of the 6th International Conference on Compiler Construction
Effectively exploiting indirect jumps
Effectively exploiting indirect jumps
The program decision logic approach to predicated execution
ISCA '99 Proceedings of the 26th annual international symposium on Computer architecture
Control CPR: a branch height reduction optimization for EPIC architectures
Proceedings of the ACM SIGPLAN 1999 conference on Programming language design and implementation
BPF+: exploiting global data-flow optimization in a generalized packet filter architecture
Proceedings of the conference on Applications, technologies, architectures, and protocols for computer communication
Branch elimination by condition merging
Software—Practice & Experience
Generalized index-set splitting
CC'05 Proceedings of the 14th international conference on Compiler Construction
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The conditional branch has long been considered an expensive operation. The relative cost of conditional branches has increased as recently designed machines are now relying on deeper pipelines and higher multiple issue. Reducing the number of conditional branches executed can often result in a substantial performance benefit. This paper describes a code-improving transformation to reorder sequences of conditional branches. First, sequences of branches that can be reordered are detected in the control flow. Second, profiling information is collected to predict the probability that each branch will transfer control out of the sequence. Third, the cost of performing each conditional branch is estimated. Fourth, the most beneficial ordering of the branches based on the estimated probability and cost is selected. The most beneficial ordering often included the insertion of additional conditional branches that did not previously exist in the sequence. Finally, the control flow is restructured to refflect the new ordering. The results of applying the transformation were significant reductions in the dynamic number of instructions and branches, as well as decreases in execution time.