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* fold shifting of constants equally to cpus

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* test adapted, e.g. 1 shl 63 needs now an explicit cast to qword for the one: qword(1) shl 63

git-svn-id: trunk@26295 -
This commit is contained in:
florian 2013-12-28 20:19:35 +00:00
parent d70a880f33
commit 89663e499b
4 changed files with 33 additions and 5 deletions
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32
compiler/nmat.pas
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@ -573,16 +573,44 @@ implementation
****************************************************************************}
function tshlshrnode.simplify(forinline : boolean):tnode;
var
lvalue,rvalue : Tconstexprint;
begin
result:=nil;
{ constant folding }
if is_constintnode(left) and is_constintnode(right) then
begin
{ x86 wraps around }
{ shl/shr are unsigned operations, so cut off upper bits }
case resultdef.size of
1:
begin
rvalue:=tordconstnode(right).value and byte($7);
lvalue:=tordconstnode(left).value and byte($ff);
end;
2:
begin
rvalue:=tordconstnode(right).value and byte($f);
lvalue:=tordconstnode(left).value and word($ffff);
end;
4:
begin
rvalue:=tordconstnode(right).value and byte($1f);
lvalue:=tordconstnode(left).value and dword($ffffffff);
end;
8:
begin
rvalue:=tordconstnode(right).value and byte($3f);
lvalue:=tordconstnode(left).value and qword($ffffffffffffffff);
end;
else
internalerror(2013122301);
end;
case nodetype of
shrn:
result:=create_simplified_ord_const(tordconstnode(left).value shr tordconstnode(right).value,resultdef,forinline);
result:=create_simplified_ord_const(lvalue shr rvalue,resultdef,forinline);
shln:
result:=create_simplified_ord_const(tordconstnode(left).value shl tordconstnode(right).value,resultdef,forinline);
result:=create_simplified_ord_const(lvalue shl rvalue,resultdef,forinline);
end;
end;
end;

2
tests/tbs/tb0295.pp
View File

@ -11,7 +11,7 @@ Var
begin
I:=2;
Writeln(i);
K:=1 shl 62;
K:=qword(1) shl 62;
For j:=1 to 61 do
begin
I:=I*2;

2
tests/webtbs/tw16328.pp
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@ -10,7 +10,7 @@ const
type
TmydbID = type Longword;
TmydbCLSID = type Word;
TmydbDBID = 0..(1 shl 48)-1; // Unique ID of the database
TmydbDBID = 0..(qword(1) shl 48)-1; // Unique ID of the database
TmydbDBTYPE = type Byte;
tarr = bitpacked array[0..10] of TmydbDBID;

2
tests/webtbs/tw22133.pp
View File

@ -19,7 +19,7 @@ begin
end;
begin
T64:=UInt64(1 shl 63);
T64:=UInt64(qword(1) shl 63);
if T64<>uint64(high(int64)+1) then
halt(1);
T64:=UInt64(1) shl 63;