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* a nil node is also a constant pointer node

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+ convert (v1=const1) and (v2=const2) into ((v1 xor const1) or (v2 xor const2))=0 if the expressions have no side effects

git-svn-id: trunk@45555 -
This commit is contained in:
florian 2020-06-01 20:50:38 +00:00
parent 19a66947bc
commit 792cf056eb
2 changed files with 71 additions and 2 deletions
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71
compiler/nadd.pas
View File

@ -493,7 +493,7 @@ implementation
t , vl, hp: tnode; t , vl, hp: tnode;
lt,rt : tnodetype; lt,rt : tnodetype;
hdef, hdef,
rd,ld : tdef; rd,ld , inttype: tdef;
rv,lv,v : tconstexprint; rv,lv,v : tconstexprint;
rvd,lvd : bestreal; rvd,lvd : bestreal;
ws1,ws2 : pcompilerwidestring; ws1,ws2 : pcompilerwidestring;
@ -505,6 +505,7 @@ implementation
res, res,
b : boolean; b : boolean;
cr, cl : Tconstexprint; cr, cl : Tconstexprint;
v2p, c2p, c1p, v1p: pnode;
begin begin
result:=nil; result:=nil;
l1:=0; l1:=0;
@ -1255,6 +1256,74 @@ implementation
exit; exit;
end; end;
{
(v1=const1) and (v2=const2)
can be converted into
((v1 xor const1) or (v2 xor const2))=0
}
if (nodetype=andn) and
(left.nodetype=equaln) and
(right.nodetype=equaln) and
(not might_have_sideeffects(left)) and
(not might_have_sideeffects(right)) and
(is_constintnode(taddnode(left).left) or is_constintnode(taddnode(left).right) or
is_constpointernode(taddnode(left).left) or is_constpointernode(taddnode(left).right)) and
(is_constintnode(taddnode(right).left) or is_constintnode(taddnode(right).right) or
is_constpointernode(taddnode(right).left) or is_constpointernode(taddnode(right).right)) then
begin
if is_constnode(taddnode(left).left) then
begin
v1p:=@taddnode(left).right;
c1p:=@taddnode(left).left;
end
else
begin
v1p:=@taddnode(left).left;
c1p:=@taddnode(left).right;
end;
if is_constnode(taddnode(right).left) then
begin
v2p:=@taddnode(right).right;
c2p:=@taddnode(right).left;
end
else
begin
v2p:=@taddnode(right).left;
c2p:=@taddnode(right).right;
end;
if v1p^.resultdef.size=v2p^.resultdef.size then
begin
if not(is_integer(v1p^.resultdef)) or not(is_integer(v2p^.resultdef)) then
begin
case v1p^.resultdef.size of
2:
inttype:=u16inttype;
4:
inttype:=u32inttype;
8:
inttype:=u64inttype;
else
Internalerror(2020060101);
end;
result:=caddnode.create_internal(equaln,
caddnode.create_internal(orn,
caddnode.create_internal(xorn,ctypeconvnode.create_internal(v1p^.getcopy,inttype),
ctypeconvnode.create_internal(c1p^.getcopy,inttype)),
caddnode.create_internal(xorn,ctypeconvnode.create_internal(v2p^.getcopy,inttype),
ctypeconvnode.create_internal(c2p^.getcopy,inttype))
),
cordconstnode.create(0,inttype,false));
end
else
result:=caddnode.create_internal(equaln,
caddnode.create_internal(orn,
caddnode.create_internal(xorn,v1p^.getcopy,c1p^.getcopy),
caddnode.create_internal(xorn,v2p^.getcopy,c2p^.getcopy)
),
cordconstnode.create(0,v1p^.resultdef,false));
end;
end;
{ even when short circuit boolean evaluation is active, this { even when short circuit boolean evaluation is active, this
optimization cannot be performed in case the node has optimization cannot be performed in case the node has
side effects, because this can change the result (e.g., in an side effects, because this can change the result (e.g., in an

2
compiler/node.pas
View File

@ -741,7 +741,7 @@ implementation
function is_constpointernode(p : tnode) : boolean; function is_constpointernode(p : tnode) : boolean;
begin begin
is_constpointernode:=(p.nodetype=pointerconstn); is_constpointernode:=(p.nodetype in [pointerconstn,niln]);
end; end;
function is_conststringnode(p : tnode) : boolean; function is_conststringnode(p : tnode) : boolean;