Mehdi Amini 6f127aff71 Define the ThinLTO Pipeline (experimental) ... Summary: On the contrary to Full LTO, ThinLTO can afford to shift compile time from the frontend to the linker: both phases are parallel (even if it is not totally "free": projects like clang are reusing product from the "compile phase" for multiple link, think about libLLVMSupport reused for opt, llc, etc.). This pipeline is based on the proposal in D13443 for full LTO. We didn't move forward on this proposal because the LTO link was far too long after that. We believe that we can afford it with ThinLTO. The ThinLTO pipeline integrates in the regular O2/O3 flow: - The compile phase perform the inliner with a somehow lighter function simplification. (TODO: tune the inliner thresholds here) This is intendend to simplify the IR and get rid of obvious things like linkonce_odr that will be inlined. - The link phase will run the pipeline from the start, extended with some specific passes that leverage the augmented knowledge we have during LTO. Especially after the inliner is done, a sequence of globalDCE/globalOpt is performed, followed by another run of the "function simplification" passes. It is not clear if this part of the pipeline will stay as is, as the split model of ThinLTO does not allow the same benefit as FullLTO without added tricks. The measurements on the public test suite as well as on our internal suite show an overall net improvement. The binary size for the clang executable is reduced by 5%. We're still tuning it with the bringup of ThinLTO and it will evolve, but this should provide a good starting point. Reviewers: tejohnson Differential Revision: http://reviews.llvm.org/D17115 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 261029		2016-02-16 23:02:29 +00:00
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Hello	Remove autoconf support	2016-01-26 21:29:08 +00:00
InstCombine	[InstCombine] Don't aggressively replace xor with icmp	2016-02-12 18:12:38 +00:00
Instrumentation	[msan] Put msan constructor in a comdat.	2016-02-12 00:37:52 +00:00
IPO	Define the ThinLTO Pipeline (experimental)	2016-02-16 23:02:29 +00:00
ObjCARC	Add support for objc_unsafeClaimAutoreleasedReturnValue to the	2016-01-27 19:05:08 +00:00
Scalar	Tweak the LICM code to reuse the first sub-loop instead of creating a new one	2016-02-15 14:48:50 +00:00
Utils	[SCEVExpander] Make findExistingExpansion smarter	2016-02-16 06:46:58 +00:00
Vectorize	[LV] Add support for insertelt/extractelt processing during type truncation	2016-02-15 15:38:17 +00:00
CMakeLists.txt
LLVMBuild.txt