diff options
Diffstat (limited to 'lib/hipe/icode/hipe_icode.erl')
-rw-r--r-- | lib/hipe/icode/hipe_icode.erl | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/lib/hipe/icode/hipe_icode.erl b/lib/hipe/icode/hipe_icode.erl index 13a0bf6141..24b7ac4783 100644 --- a/lib/hipe/icode/hipe_icode.erl +++ b/lib/hipe/icode/hipe_icode.erl @@ -1,9 +1,5 @@ %% -*- erlang-indent-level: 2 -*- %% -%% %CopyrightBegin% -%% -%% Copyright Ericsson AB 2001-2016. All Rights Reserved. -%% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. %% You may obtain a copy of the License at @@ -16,8 +12,6 @@ %% See the License for the specific language governing permissions and %% limitations under the License. %% -%% %CopyrightEnd% -%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% HiPE Intermediate Code %% ==================================================================== @@ -30,9 +24,6 @@ %% 2003-03-15 ES ([email protected]): %% Started commenting in Edoc. %% Moved pretty printer to separate file. -%% -%% $Id$ -%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%@doc @@ -438,6 +429,7 @@ if_true_label/1, if_false_label/1, if_args/1, + if_args_update/2, if_pred/1, %% is_if/1, @@ -594,6 +586,7 @@ uses/1, defines/1, is_safe/1, + reduce_unused/1, strip_comments/1, subst/2, subst_uses/2, @@ -713,6 +706,9 @@ if_op_update(IF, NewOp) -> IF#icode_if{op=NewOp}. -spec if_args(#icode_if{}) -> [icode_term_arg()]. if_args(#icode_if{args=Args}) -> Args. +-spec if_args_update(#icode_if{}, [icode_term_arg()]) -> #icode_if{}. +if_args_update(IF, Args) -> IF#icode_if{args=Args}. + -spec if_true_label(#icode_if{}) -> icode_lbl(). if_true_label(#icode_if{true_label=TrueLbl}) -> TrueLbl. @@ -1765,6 +1761,18 @@ is_safe(Instr) -> #icode_end_try{} -> false end. +%% @doc Produces a simplified instruction sequence that is equivalent to [Instr] +%% under the assumption that all results of Instr are unused, or 'false' if +%% there is no such sequence (other than [Instr] itself). + +-spec reduce_unused(icode_instr()) -> false | [icode_instr()]. + +reduce_unused(Instr) -> + case is_safe(Instr) of + true -> []; + false -> false + end. + %%----------------------------------------------------------------------- -spec highest_var(icode_instrs()) -> non_neg_integer(). |