paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-13 04:09:33 +02:00
Code Issues Packages Projects Releases Wiki Activity

* arm/a64: Added new TST post-peephole optimisation to replace previous AND/CMP/B(c) optimisation

Browse Source
This commit is contained in:
J. Gareth "Curious Kit" Moreton 2023-10-22 04:10:33 +01:00 committed by FPK
parent b18c10d0d8
commit bf29f2051c
1 changed files with 43 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
compiler/aarch64/aoptcpu.pas
View File

@ -67,6 +67,7 @@ Interface
function PostPeepholeOptAND(var p: tai): Boolean;
function PostPeepholeOptCMP(var p: tai): boolean;
function PostPeepholeOptTST(var p: tai): Boolean;
End;
Implementation
@ -1169,6 +1170,46 @@ Implementation
end;
function TCpuAsmOptimizer.PostPeepholeOptTST(var p : tai): boolean;
var
hp1: tai;
hp3: taicpu;
bitval : cardinal;
begin
Result:=false;
{
tst reg1,<const=power of 2>
b.e/b.ne label
into
tb(n)z reg0,<power of 2>,label
}
if MatchOpType(taicpu(p),top_reg,top_const) and
(PopCnt(QWord(taicpu(p).oper[1]^.val))=1) and
GetNextInstruction(p,hp1) and
MatchInstruction(hp1,A_B,[C_EQ,C_NE],[PF_None]) then
begin
bitval:=BsfQWord(qword(taicpu(p).oper[1]^.val));
case taicpu(hp1).condition of
C_NE:
hp3:=taicpu.op_reg_const_ref(A_TBNZ,taicpu(p).oper[0]^.reg,bitval,taicpu(hp1).oper[0]^.ref^);
C_EQ:
hp3:=taicpu.op_reg_const_ref(A_TBZ,taicpu(p).oper[0]^.reg,bitval,taicpu(hp1).oper[0]^.ref^);
else
Internalerror(2021100210);
end;
taicpu(hp3).fileinfo:=taicpu(p).fileinfo;
asml.insertafter(hp3, p);
RemoveInstruction(hp1);
RemoveCurrentP(p, hp3);
DebugMsg(SPeepholeOptimization + 'TST; B(E/NE) -> TB(Z/NZ) done', p);
Result:=true;
end;
end;
function TCpuAsmOptimizer.PrePeepHoleOptsCpu(var p: tai): boolean;
begin
result := false;
@ -1285,6 +1326,8 @@ Implementation
Result:=PostPeepholeOptCMP(p);
A_AND:
Result:=PostPeepholeOptAND(p);
A_TST:
Result:=PostPeepholeOptTST(p);
else
;
end;