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* optimize case statements with a single branch into if statements (ord const only)

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git-svn-id: trunk@43766 -
This commit is contained in:
florian 2019-12-23 22:42:53 +00:00
parent cb44d7d4e2
commit abb79553d2
1 changed files with 24 additions and 1 deletions
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25
compiler/nset.pas
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@ -919,8 +919,31 @@ implementation
end; end;
result:=cifnode.create(left,node_thenblock,node_elseblock); result:=cifnode.create(left,node_thenblock,node_elseblock);
left:=nil; left:=nil;
exit;
end; end;
end; { convert single case branch into if-statement }
if (flabels^.greater=nil) and (flabels^.less=nil) then
if flabels^.label_type=ltOrdinal then
begin
if flabels^._low=flabels^._high then
begin
result:=cifnode.create_internal(
caddnode.create_internal(equaln,left.getcopy,cordconstnode.create(flabels^._low,left.resultdef,false)),
pcaseblock(blocks[flabels^.blockid])^.statement.getcopy,elseblock);
end
else
begin
result:=cifnode.create_internal(
caddnode.create_internal(andn,
caddnode.create_internal(gten,left.getcopy,cordconstnode.create(flabels^._low,left.resultdef,false)),
caddnode.create_internal(lten,left.getcopy,cordconstnode.create(flabels^._high,left.resultdef,false))
),
pcaseblock(blocks[flabels^.blockid])^.statement.getcopy,elseblock);
end;
elseblock:=nil;
exit;
end;
end;
function tcasenode.simplify(forinline:boolean):tnode; function tcasenode.simplify(forinline:boolean):tnode;