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path: root/lib/hipe/regalloc/Makefile
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2017-05-04Update copyright yearRaimo Niskanen
2017-03-16hipe: Add range splitter range_splitMagnus Lång
hipe_range_split is a complex live range splitter, more sophisticated thatn hipe_restore_reuse, but still targeted specifically at temporaries forced onto stack by being live over call instructions. hipe_range_split partitions the control flow graph at call instructions, like hipe_regalloc_prepass. Splitting decisions are made on a per partition and per temporary basis. There are three different ways in which hipe_range_split may choose to split a temporary in a program partition: * Mode1: Spill the temp before calls, and restore it after them * Mode2: Spill the temp after definitions, restore it after calls * Mode3: Spill the temp after definitions, restore it before uses To pick which of these should be used for each temp×partiton pair, hipe_range_split uses a cost function. The cost is simply the sum of the cost of all expected stack accesses, and the cost for an individual stack access is based on the probability weight of the basic block that it resides in. This biases the range splitter so that it attempts moving stack accesses from a functions hot path to the cold path. hipe_bb_weights is used to compute the probability weights. mode3 is effectively the same as what hipe_restore_reuse does. Because of this, hipe_restore_reuse reuses the analysis pass of hipe_restore_reuse in order to compute the minimal needed set of spills and restores. The reason mode3 was introduced to hipe_range_split rather than simply composing it with hipe_restore_reuse (by running both) is that such a composition resulted in poor register allocation results due to insufficiently strong move coalescing in the register allocator. The cost function heuristic has a couple of tuning knobs: * {range_split_min_gain, Gain} (default: 1.1, range: [0.0, inf)) The minimum proportional improvement that the cost of all stack accesses to a temp must display in order for that temp to be split. * {range_split_mode1_fudge, Factor} (default: 1.1, range: [0.0, inf)) Costs for mode1 are multiplied by this factor in order to discourage it when it provides marginal benefits. The justification is that mode1 causes temps to be live for longest, thus leading to higher register pressure. * {range_split_weight_power, Factor} (default: 2, range: (0.0, inf)) Adjusts how much effect the basic block weights have on the cost of a stack access. A stack access in a block with weight 1.0 has cost 1.0, a stack access in a block with weight 0.01 has cost 1/Factor. Additionally, the option range_split_weights chooses whether the basic block weights are used at all. In the case that the input is very big, hipe_range_split automatically falls back to hipe_restore_reuse only in order to keep compile times under control. Note that this is not only because of hipe_range_split being slow, but also due to the resulting program being slow to register allocate, and is not as partitionable by hipe_regalloc_prepass. hipe_restore_reuse, on the other hand, does not affect the programs partitionability. The hipe_range_split pass is controlled by a new option ra_range_split. ra_range_split is added to o2, and ra_restore_reuse is disabled in o2.
2017-03-16hipe: Add range splitter restore_reuseMagnus Lång
hipe_restore_reuse is a simplistic range splitter that splits temps that are forced onto the stack by being live over call instructions. In particular, it attempts to avoid cases where there are several accesses to such stack allocated temps in straight-line code, uninterrupted by any calls. In order to achieve this it splits temps between just before the first access(es) and just after the last access(es) in such straight-line code groups. The hipe_restore_reuse pass is controlled by a new option ra_restore_reuse. ra_restore_reuse is added to o1.
2016-09-02hipe: Add hipe_regalloc_prepassMagnus Lång
hipe_regalloc_prepass speeds up register allocation by spilling any temp that is live over a call (which clobbers all register). In order to detect these, a new function was added to the target interface; defines_all_alloc/1, that takes an instruction and returns a boolean.
2016-07-11hipe_vectors: Change implementation to 'array'Magnus Lång
The 'array' module is highly optimised for the hipe_vectors use-case, and seems to perform slightly better than the gb_trees implementation. Also, we remove the completely unnecessary hipe_vectors.hrl header.
2016-05-31Add compiler option -Werror to MakefilesKostis Sagonas
and correct the name of another, erroneously spelt, option in the process.
2016-03-15update copyright-yearHenrik Nord
2015-06-18Change license text to APLv2Bruce Yinhe
2012-06-05Update to work with whitespace in exec pathLukas Larsson
OTP-10106 OTP-10107
2012-03-30Update copyright yearsBjörn-Egil Dahlberg
2012-02-28Make hipe hipe-compiled w/ --enable-native-libsPatrik Nyblom
2010-01-26OTP-8343 The documentation is now possible to build in an open sourceLars G Thorsen
environment after a number of bugs are fixed and some features are added in the documentation build process. - The arity calculation is updated. - The module prefix used in the function names for bif's are removed in the generated links so the links will look like http://www.erlang.org/doc/man/erlang.html#append_element-2 instead of http://www.erlang.org/doc/man/erlang.html#erlang:append_element-2 - Enhanced the menu positioning in the html documentation when a new page is loaded. - A number of corrections in the generation of man pages (thanks to Sergei Golovan) - Moved some man pages to more apropriate sections, pages in section 4 moved to 5 and pages in 6 moved to 7. - The legal notice is taken from the xml book file so OTP's build process can be used for non OTP applications.
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP