diff options
Diffstat (limited to 'lib/compiler/src/beam_flatten.erl')
| -rw-r--r-- | lib/compiler/src/beam_flatten.erl | 55 |
1 files changed, 17 insertions, 38 deletions
diff --git a/lib/compiler/src/beam_flatten.erl b/lib/compiler/src/beam_flatten.erl index 6c7cb849aa..25428c0c10 100644 --- a/lib/compiler/src/beam_flatten.erl +++ b/lib/compiler/src/beam_flatten.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1999-2010. All Rights Reserved. +%% Copyright Ericsson AB 1999-2013. All Rights Reserved. %% %% The contents of this file are subject to the Erlang Public License, %% Version 1.1, (the "License"); you may not use this file except in @@ -79,49 +79,28 @@ norm_allocate({nozero,Ns,Nh,Inits}, Regs) -> %% insert_alloc_in_bs_init(ReverseInstructionStream, AllocationInfo) -> %% impossible | ReverseInstructionStream' -%% A bs_init2/6 instruction should not be followed by a test heap instruction. +%% A bs_init/6 instruction should not be followed by a test heap instruction. %% Given the AllocationInfo from a test heap instruction, merge the -%% allocation amounts into the previous bs_init2/6 instruction (if any). +%% allocation amounts into the previous bs_init/6 instruction (if any). %% -insert_alloc_in_bs_init([I|_]=Is, Alloc) -> - case is_bs_constructor(I) of - false -> impossible; - true -> insert_alloc_1(Is, Alloc, []) - end. - -insert_alloc_1([{bs_init2=Op,Fail,Bs,Ws1,Regs,F,Dst}|Is], {_,nostack,Ws2,[]}, Acc) -> - Al = beam_utils:combine_heap_needs(Ws1, Ws2), - I = {Op,Fail,Bs,Al,Regs,F,Dst}, - reverse(Acc, [I|Is]); -insert_alloc_1([{bs_init_bits=Op,Fail,Bs,Ws1,Regs,F,Dst}|Is], {_,nostack,Ws2,[]}, Acc) -> - Al = beam_utils:combine_heap_needs(Ws1, Ws2), - I = {Op,Fail,Bs,Al,Regs,F,Dst}, - reverse(Acc, [I|Is]); -insert_alloc_1([{bs_append,Fail,Sz,Ws1,Regs,U,Bin,Fl,Dst}|Is], - {_,nostack,Ws2,[]}, Acc) -> +insert_alloc_in_bs_init([{bs_put,_,_,_}=I|Is], Alloc) -> + %% The instruction sequence ends with an bs_put/4 instruction. + %% We'll need to search backwards for the bs_init/6 instruction. + insert_alloc_1(Is, Alloc, [I]); +insert_alloc_in_bs_init(_, _) -> impossible. + +insert_alloc_1([{bs_init=Op,Fail,Info0,Live,Ss,Dst}|Is], + {_,nostack,Ws2,[]}, Acc) when is_integer(Live) -> + %% The number of extra heap words is always in the second position + %% in the Info tuple. + Ws1 = element(2, Info0), Al = beam_utils:combine_heap_needs(Ws1, Ws2), - I = {bs_append,Fail,Sz,Al,Regs,U,Bin,Fl,Dst}, + Info = setelement(2, Info0, Al), + I = {Op,Fail,Info,Live,Ss,Dst}, reverse(Acc, [I|Is]); -insert_alloc_1([I|Is], Alloc, Acc) -> +insert_alloc_1([{bs_put,_,_,_}=I|Is], Alloc, Acc) -> insert_alloc_1(Is, Alloc, [I|Acc]). - -%% is_bs_constructor(Instruction) -> true|false. -%% Test whether the instruction is a bit syntax construction -%% instruction that can occur at the end of a bit syntax -%% construction. (Since an empty binary would be expressed -%% as a literal, the bs_init2/6 instruction will not occur -%% at the end and therefore it is no need to test for it here.) -%% -is_bs_constructor({bs_put_integer,_,_,_,_,_}) -> true; -is_bs_constructor({bs_put_utf8,_,_,_}) -> true; -is_bs_constructor({bs_put_utf16,_,_,_}) -> true; -is_bs_constructor({bs_put_utf32,_,_,_}) -> true; -is_bs_constructor({bs_put_float,_,_,_,_,_}) -> true; -is_bs_constructor({bs_put_binary,_,_,_,_,_}) -> true; -is_bs_constructor({bs_put_string,_,_}) -> true; -is_bs_constructor(_) -> false. - %% opt(Is0) -> Is %% Simple peep-hole optimization to move a {move,Any,{x,0}} past %% any kill up to the next call instruction. (To give the loader |