paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-06-25 12:18:20 +02:00
Code Issues Packages Projects Releases Wiki Activity

+ simplify shl/shr x, if (x mod bitsizeof(left))=0

Browse Source 
git-svn-id: trunk@26628 -
This commit is contained in:
florian 2014-01-30 17:34:33 +00:00
parent b1f54b2853
commit cd235d8409
1 changed files with 47 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

83
compiler/nmat.pas
View File

@ -578,47 +578,58 @@ implementation
begin begin
result:=nil; result:=nil;
{ constant folding } { constant folding }
if is_constintnode(left) and is_constintnode(right) then if is_constintnode(right) then
begin begin
if forinline then if forinline then
begin
{ shl/shr are unsigned operations, so cut off upper bits }
case resultdef.size of
1:
rvalue:=tordconstnode(right).value and byte($7);
2:
rvalue:=tordconstnode(right).value and byte($f);
4:
rvalue:=tordconstnode(right).value and byte($1f);
8:
rvalue:=tordconstnode(right).value and byte($3f);
else
internalerror(2013122302);
end;
end
else
rvalue:=tordconstnode(right).value;
if is_constintnode(left) then
begin begin
{ shl/shr are unsigned operations, so cut off upper bits } if forinline then
case resultdef.size of begin
1: { shl/shr are unsigned operations, so cut off upper bits }
begin case resultdef.size of
rvalue:=tordconstnode(right).value and byte($7); 1:
lvalue:=tordconstnode(left).value and byte($ff); lvalue:=tordconstnode(left).value and byte($ff);
2:
lvalue:=tordconstnode(left).value and word($ffff);
4:
lvalue:=tordconstnode(left).value and dword($ffffffff);
8:
lvalue:=tordconstnode(left).value and qword($ffffffffffffffff);
else
internalerror(2013122301);
end; end;
2: end
begin else
rvalue:=tordconstnode(right).value and byte($f); lvalue:=tordconstnode(left).value;
lvalue:=tordconstnode(left).value and word($ffff); case nodetype of
end; shrn:
4: result:=create_simplified_ord_const(lvalue shr rvalue,resultdef,forinline);
begin shln:
rvalue:=tordconstnode(right).value and byte($1f); result:=create_simplified_ord_const(lvalue shl rvalue,resultdef,forinline);
lvalue:=tordconstnode(left).value and dword($ffffffff);
end;
8:
begin
rvalue:=tordconstnode(right).value and byte($3f);
lvalue:=tordconstnode(left).value and qword($ffffffffffffffff);
end;
else
internalerror(2013122301);
end; end;
end end
else else if rvalue=0 then
begin begin
rvalue:=tordconstnode(right).value; result:=left;
lvalue:=tordconstnode(left).value; left:=nil;
end; end;
case nodetype of
shrn:
result:=create_simplified_ord_const(lvalue shr rvalue,resultdef,forinline);
shln:
result:=create_simplified_ord_const(lvalue shl rvalue,resultdef,forinline);
end;
end; end;
end; end;