Embedded2010.04.22 21:12
GCC4.5.0이 발표되었습니다.

가장 큰 특징은 Link Time Optimization입니다. 이전에는 모듈 단위의 컴파일에서 최적화를 수행할 수 있었는데 이제는 모듈들을 링크해서 묶을때에도 최적화를 시킬 수 있습니다.  이것에 의해서 성능과 크기에 대한 최적화를 얻을 수 있다고 합니다.
LD로 메모리 올릴떄는 최적화가 되진 않을 것 같지만, 여러개의 모듈들을 하나의 Static으로 만들떄는 최적화가 될 것 같습니다.  

두번째 최적화 포인트는 루프 최적화입니다. 중첩 루프에 대한 최적화 방안인 Polytope 모델을 적용했습니다.
- 어려워서 패스~~

이에 관해서는 아래 링크를 참조하시기 바랍니다.

버그 수정 본은 2010년 7월경에 4.5.1로 내놓을 예정이라고 하네요
빠르기도 하시지~



The Free Software Foundation and the GNU Compiler Collection (GCC)
development team have released GCC 4.5.0.  This release is a major
upgrade to the compilers, with a particular focus on the performance
of the generated code.  The developers have measured performance
improvements of 5% to 10% on high-performance computing benchmarks.
(Of course, results vary depending on choice of CPU, benchmark, and
optimization options.)

GCC 4.5.0 is now capable of "link-time optimization".  Traditionally,
most C and C++ compilers (including GCC) have only been able to
optimize within a single source file or "module".  GCC was therefore
unable to take advantage of optimization opportunities that required
knowledge about multiple modules.  This limitation has been removed in
GCC 4.5.0.  This optimization can provide significant increases in
performance and equally significant reductions in code size.

In addition, GCC 4.5.0 has improved loop optimization infrastructure.
This infrastructure, based on an advanced "polyhedral" model for
optimization, allows GCC to perform more advanced loop optimizations.
In the future, this infrastructure will be tuned and used more heavily.

GCC 4.5.0 also features improvements for a wide variety of specific
architectures, including support for recent CPUs using the ARM, AVR,
ColdFire, MIPS, Power, SuperH, and x86 architectures.  GCC also
generates better debug information for optimized code, including
information about the value of variables that have been optimized
away.  And, of course, a wide variety of defects in all parts of the
compiler (ranging from language conformance to code-generation) have
been corrected.

Refer to gcc.gnu.org:


for more information about this release.

GCC 4.5.1, with corrections for any critical defects reported in GCC
4.5.0, is expected in July, 2010.

As always, a vast number of people contributed to this GCC release --
far too many to thank individually!  

Mark Mitchell

Posted by GUNDAM_IM