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-rw-r--r--lib/hipe/x86/hipe_x86_postpass.erl56
1 files changed, 32 insertions, 24 deletions
diff --git a/lib/hipe/x86/hipe_x86_postpass.erl b/lib/hipe/x86/hipe_x86_postpass.erl
index 939baeccec..925054dd68 100644
--- a/lib/hipe/x86/hipe_x86_postpass.erl
+++ b/lib/hipe/x86/hipe_x86_postpass.erl
@@ -1,9 +1,5 @@
%%% -*- erlang-indent-level: 2 -*-
%%%
-%%% %CopyrightBegin%
-%%%
-%%% Copyright Ericsson AB 2003-2016. 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
@@ -15,8 +11,6 @@
%%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%%% See the License for the specific language governing permissions and
%%% limitations under the License.
-%%%
-%%% %CopyrightEnd%
%%%
%%%----------------------------------------------------------------------
%%% File : hipe_x86_postpass.erl
@@ -63,9 +57,10 @@ postpass(#defun{code=Code0}=Defun, Options) ->
peephole_optimization(Insns) ->
peep(Insns, [], []).
-%% MoveSelf related peep-opts
+
+%% MoveSelf related peep-opts
%% ------------------------------
-peep([#fmove{src=Src, dst=Src} | Insns], Res,Lst) ->
+peep([#fmove{src=Src, dst=Src} | Insns], Res,Lst) ->
peep(Insns, Res, [moveSelf1|Lst]);
peep([I=#fmove{src=Src, dst=Dst},
#fmove{src=Dst, dst=Src} | Insns], Res,Lst) ->
@@ -95,7 +90,8 @@ peep([I=#move{src=#x86_temp{reg=Src}, dst=#x86_temp{reg=Dst}},
%% ElimBinALMDouble
%% ----------------
-peep([Move=#move{src=Src, dst=Dst}, Alu=#alu{src=Src, dst=Dst}|Insns], Res, Lst) ->
+peep([Move=#move{src=Src, dst=Dst}, Alu=#alu{src=Src, dst=Dst}|Insns], Res, Lst)
+ when not is_record(Dst, x86_mem) ->
peep([Alu#alu{src=Dst}|Insns], [Move|Res], [elimBinALMDouble|Lst]);
@@ -119,19 +115,15 @@ peep([#move{src=Src1, dst=Dst},
%% ElimCmp0
%% --------
-peep([C=#cmp{src=Src, dst=Dst},J=#jcc{cc=Cond, label=Lab}|Insns],Res,Lst) ->
- case (((Src =:= #x86_imm{value=0}) or (Dst =:= #x86_imm{value=0})) and
- ((Cond =:= 'eq') or (Cond =:= 'neq'))) of
- true ->
- Src2 = case Src of #x86_imm{value=0} -> Src; _ -> Dst end,
- Cond2 = case Cond of 'eq' -> 'z'; 'neq' -> 'nz' end,
- Test = #test{src=Src2, dst=#x86_imm{value=0}},
- Jump = #jcc{cc=Cond2, label=Lab},
- peep(Insns, [Jump, Test|Res], [elimCmp0|Lst]);
- _ ->
- peep(Insns, [J,C|Res], Lst)
- end;
-
+peep([#cmp{src=#x86_imm{value=0}, dst=Dst=#x86_temp{}}|Insns],Res,Lst) ->
+ %% TEST leaves the adjust flag undefined, whereas CMP sets it properly (in
+ %% this case to 0). However, since HiPE does not use any instructions that
+ %% read the adjust flag, we can do this transform safely.
+ peep(Insns, [#test{src=Dst, dst=Dst} | Res], [elimCmp0_1|Lst]);
+peep([#cmp{src=Src=#x86_temp{}, dst=#x86_imm{value=0}},
+ J=#jcc{cc=Cond}|Insns],Res,Lst)
+ when Cond =:= 'e'; Cond =:= 'ne' -> % We're commuting the comparison
+ peep(Insns, [J, #test{src=Src, dst=Src} | Res], [elimCmp0_2|Lst]);
%% ElimCmpTest
%% -----------
@@ -168,8 +160,7 @@ peep([#jcc{label=Lab}, I=#label{label=Lab}|Insns], Res, Lst) ->
%% ElimSet0
%% --------
-peep([#move{src=#x86_imm{value=0},dst=Dst}|Insns],Res,Lst)
-when (Dst==#x86_temp{}) ->
+peep([#move{src=#x86_imm{value=0},dst=Dst=#x86_temp{}}|Insns],Res,Lst) ->
peep(Insns, [#alu{aluop='xor', src=Dst, dst=Dst}|Res], [elimSet0|Lst]);
%% ElimMDPow2
@@ -186,6 +177,18 @@ peep([B = #alu{aluop=Op,src=#x86_imm{value=Val},dst=Dst}|Insns], Res, Lst) ->
peep(Insns, [B|Res], Lst)
end;
+%% LeaToAdd
+%% This rule transforms lea into add when the destination is the same as one of
+%% the operands. Sound because lea is never used where the condition codes are
+%% live (and would be clobbered by add).
+%% ----------
+peep([#lea{mem=#x86_mem{base=#x86_temp{reg=DstR},off=Src},
+ temp=Dst=#x86_temp{reg=DstR}}|Insns], Res, Lst) ->
+ peep(Insns, [#alu{aluop='add',src=Src,dst=Dst}|Res], [leaToAdd|Lst]);
+peep([#lea{mem=#x86_mem{base=Src,off=#x86_temp{reg=DstR}},
+ temp=Dst=#x86_temp{reg=DstR}}|Insns], Res, Lst) ->
+ peep(Insns, [#alu{aluop='add',src=Src,dst=Dst}|Res], [leaToAdd|Lst]);
+
%% SubToDec
%% This rule turns "subl $1,Dst; jl Lab" into "decl Dst; jl Lab", which
%% changes reduction counter tests to use decl instead of subl.
@@ -208,6 +211,11 @@ trivial_goto_elimination(Insns) -> goto_elim(Insns, []).
goto_elim([#jmp_label{label=Label}, I = #label{label=Label}|Insns], Res) ->
goto_elim([I|Insns], Res);
+goto_elim([#jcc{cc=CC, label=Label} = IJCC,
+ #jmp_label{label=BranchTgt},
+ #label{label=Label} = ILBL|Insns], Res) ->
+ goto_elim([IJCC#jcc{cc=hipe_x86:neg_cc(CC), label=BranchTgt},
+ ILBL|Insns], Res);
goto_elim([I | Insns], Res) ->
goto_elim(Insns, [I|Res]);
goto_elim([], Res) ->