Advanced Optimization Features

Mac hardware based on Intel processors can also benefit from advanced optimization features, a few of which are explained briefly here, with links to more complete descriptions.

• Auto-vectorization parallelizes code to utilize the Streaming SIMD Extensions (SSE) instruction set architectures (SSE, SSE2, SSE3, SSSE3, and SSE4) of our latest processors.
• High-Performance Parallel Optimizer (HPO) restructures and optimizes loops to ensure that auto-vectorization, OpenMP, or auto-paralllelization best utilizes the processor’s capabilities for cache and memory accesses, SIMD instruction sets, and for multiple cores. This revolutionary capability, new for 10.0, combines vectorization, parallelization and loop transformations into a single pass which is faster, more effective and more reliable than prior discrete phases.
• Interprocedural Optimization (IPO) dramatically improves performance of small- or medium-sized functions that are used frequently, especially programs that contain calls within loops. The analysis capabilities of this optimizer can also give feedback on vulnerabilities and coding errors, such as uninitialized variables or OpenMP API issues, which cannot be detected as well by compilers which rely strictly on analysis by a compiler front-end.
• Profile-Guided Optimization (PGO) improves application performance by reducing instruction-cache thrashing, reorganizing code layout, shrinking code size, and reducing branch mispredictions.
• Optimized Code Debugging with the Intel® Debugger improves the efficiency of the debugging process on code that has been optimized for Intel® architecture.