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2017-10-27Eliminate the v3_life passBjörn Gustavsson
The v3_life pass does not do enough to be worth being its own pass. Essentially it does two things: * Calculates life-time information starting from the annotations that v3_kernel provides. That part can be moved into v3_codegen. * Rewrites the Kernel Erlang records to similar plain tuples (for example, #k_cons{hd=Hd,tl=Tl} is rewritten to {cons,Hd,Tl}). That rewriting is not needed and can be eliminated.
2017-01-12v3_life: Add types and specsBjörn Gustavsson
2016-11-18v3_kernel: Generate optimized code for guardsBjörn Gustavsson
The compiler produces poor code for complex guard expressions with andalso/orelse. Here is an example from the filename module: -define(IS_DRIVELETTER(Letter),(((Letter >= $A) andalso (Letter =< $Z)) orelse ((Letter >= $a) andalso (Letter =< $z)))). skip_prefix(Name, false) -> Name; skip_prefix([L, DrvSep|Name], DrvSep) when ?IS_DRIVELETTER(L) -> Name; skip_prefix(Name, _) -> Name. beam_bool fails to simplify the code for the guard, leaving several 'bif' instructions: {function, skip_prefix, 2, 49}. {label,48}. {line,[{location,"filename.erl",187}]}. {func_info,{atom,filename},{atom,skip_prefix},2}. {label,49}. {test,is_ne_exact,{f,52},[{x,1},{atom,false}]}. {test,is_nonempty_list,{f,52},[{x,0}]}. {get_list,{x,0},{x,2},{x,3}}. {test,is_nonempty_list,{f,52},[{x,3}]}. {get_list,{x,3},{x,4},{x,5}}. {bif,'=:=',{f,52},[{x,1},{x,4}],{x,6}}. {test,is_ge,{f,50},[{x,2},{integer,65}]}. {bif,'=<',{f,52},[{x,2},{integer,90}],{x,7}}. {test,is_eq_exact,{f,51},[{x,7},{atom,false}]}. {test,is_ge,{f,50},[{x,2},{integer,97}]}. {bif,'=<',{f,52},[{x,2},{integer,122}],{x,7}}. {jump,{f,51}}. {label,50}. {move,{atom,false},{x,7}}. {label,51}. {bif,'=:=',{f,52},[{x,7},{atom,true}],{x,7}}. {test,is_eq_exact,{f,52},[{x,6},{atom,true}]}. {test,is_eq_exact,{f,52},[{x,7},{atom,true}]}. {move,{x,5},{x,0}}. return. {label,52}. return. We can add optimizations of guard tests to v3_kernel to achive a better result: {function, skip_prefix, 2, 49}. {label,48}. {line,[{location,"filename.erl",187}]}. {func_info,{atom,filename},{atom,skip_prefix},2}. {label,49}. {test,is_ne_exact,{f,51},[{x,1},{atom,false}]}. {test,is_nonempty_list,{f,51},[{x,0}]}. {get_list,{x,0},{x,2},{x,3}}. {test,is_nonempty_list,{f,51},[{x,3}]}. {get_list,{x,3},{x,4},{x,5}}. {test,is_eq_exact,{f,51},[{x,1},{x,4}]}. {test,is_ge,{f,51},[{x,2},{integer,65}]}. {test,is_lt,{f,50},[{integer,90},{x,2}]}. {test,is_ge,{f,51},[{x,2},{integer,97}]}. {test,is_ge,{f,51},[{integer,122},{x,2}]}. {label,50}. {move,{x,5},{x,0}}. return. {label,51}. return. Looking at the STDLIB application, there were 112 lines of BIF calls in guards that beam_bool failed to convert to test instructions. This commit eliminates all those BIF calls. Here is how I counted the instructions: $ PATH=$ERL_TOP/bin:$PATH erlc -I ../include -I ../../kernel/include -S *.erl $ grep "bif,'[=<>]" *.S | grep -v f,0 dets.S: {bif,'=:=',{f,547},[{x,4},{atom,read_write}],{x,4}}. dets.S: {bif,'=:=',{f,547},[{x,5},{atom,saved}],{x,5}}. dets.S: {bif,'=:=',{f,589},[{x,5},{atom,read}],{x,5}}. . . . $ grep "bif,'[=<>]" *.S | grep -v f,0 | wc 112 224 6765 $
2016-09-21Simplify handling of internal BIFsBjörn Gustavsson
Do a simpler translation of internal BIFs. While we are it, also remove the dummy values of Index and Uniq from the make_fun internal operation.
2016-09-21v3_life: Eliminate special handling of guardsBjörn Gustavsson
Remove the special handling #k_try{} in guards in v3_life. If we introduce a new #k_protected{} record in v3_kernel, v3_life no longer needs to know whether it is processing guards or bodies.
2016-03-15update copyright-yearHenrik Nord
2015-06-18Change license text to APLv2Bruce Yinhe
2015-05-21v3_life: Refactor variable dbBjörn-Egil Dahlberg
2015-04-22v3_life: Optimize updating of the variable data baseBjörn Gustavsson
Updating of the variable data base takes most of the time.
2015-03-11v3_life: Combine literal/2 and literal2/2Björn Gustavsson
For unclear reasons, there are two functions in v3_life that are almost identical: literal/2 and literal2/2. literal/2 is used for expressions and literal2/2 for patterns. It turns out that literal2/2 can do everything that literal/2 can do, except that it transforms maps differently. If we adjust v3_codegen to accept the same format of maps in expressions and patterns, we can rename literal2/2 to literal/2 and use it for expressions and patterns.
2014-03-25compiler: map_pair cannot be a type clause in v3_lifeBjörn-Egil Dahlberg
Map pairs are encapsulated in a map.
2014-02-07compiler: Fix codegen multiple updates for MapsBjörn-Egil Dahlberg
This fixes an error on multiple updates optimization for map pairs. The error was introduced with moving to term order in Maps. This also fixes an error where register life time was lost for values and could result in erroneuos values being emitted in for map pairs. Simplified v3_codegen by moving multiple update optimizations to v3_kernel.
2014-01-29compiler: Squash #k_map_pair_*{} to #k_map_pair{}Björn-Egil Dahlberg
Simplify compiler internals for kernel passes.
2014-01-28Pass the map pair operators through to the v3_codegen passBjörn Gustavsson
2014-01-28Implement support for maps in the compilerBjörn Gustavsson
To make it possible to build the entire OTP system, also define dummys for the instructions in ops.tab.
2012-03-30Update copyright yearsBjörn-Egil Dahlberg
2012-03-14v3_life: Use common code for guards and bodiesBjörn Gustavsson
2012-01-11v3_kernel.hrl: Remove unused record #k_string{}Björn Gustavsson
2012-01-04Eliminate the match_fail primop in v3_kernel and later passesBjörn Gustavsson
In the v3_life pass, it is assumed that a 'match_fail' primop only occur at the top-level and at the end of a function. But this code: do_split_cases(A) -> case A of x -> Z = dummy1; _ -> Z = dummy2, a=b end, Z. will be optimized by sys_core_fold to the following code: 'split_cases'/1 = fun (_cor0) -> let <_cor7,Z> = case _cor0 of <'x'> when 'true' -> < 'dummy1','dummy1' > <_cor6> when 'true' -> %% Here follows a 'match_fail' primop inside %% multiple return values: < primop 'match_fail'({'badmatch','b'}),'dummy2' > end in Z moving the 'match_fail' primop into a "values" construction. In the future, we would like to get rid of the v3_life pass (it is there for historical reasons), so in the mean-time we prefer to not add more code to it by generalizing the handling of 'match_fail'. Since the 'match_fail' primop can be simulated by erlang:error/{1,2}, the simplest solution is to translate 'match_fail' to a call to erlang:error/{1,2} in v3_kernel and remove the handling of 'match_fail' in v3_life and v3_codegen. It is tempting to get rid of 'match_fail' also in the Core Erlang format, but there are two issues: - Removing the support for 'match_fail' completely may break tools that generate Core Erlang code. We should not do that in a minor release. - There is no easy way to generate a 'function_clause' exception that will remain correct if it will be inlined into another function. (Calling "erlang:error(function_clause, Args)" is fine only if it is not inlined into another function.) A good solution probably involves introducing new instructions, which is better done in a major release. Noticed-by: Håkan Matsson Minimized-test-case-by: Erik Søe Sørensen
2011-12-09Update copyright yearsBjörn-Egil Dahlberg
2011-08-16compiler: Generate line instructionsBjörn Gustavsson
2010-05-20v3_life: Remove clause that cannot match in match_fail/3Björn Gustavsson
The clause that attempts to match a #k_literal{} where the value is an atom cannot possibly match, since single atoms are always encoded as #k_atom{}.
2010-03-22compiler: Don't support the no_constant_pool optionBjörn Gustavsson
The no_constant_pool option was implied by the r11 option. It turns off the usage of the constant (literal) pool, so that BEAM instructions that use constants can be loaded in an R11 system. Since the r11 option has been removed, there is no need to retain the no_constant_pool option.
2010-03-17compiler: Provide more information if the v3_life pass crashesBjörn Gustavsson
Print the name and arity of the function being compiled if the v3_life compiler pass crashes to facilitate finding out which part of the source code that triggered the problem.
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP