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PostPeepholeOptTestOr now removes TEST when dealing with POPCNT and LZCNT

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This commit is contained in:
J. Gareth "Curious Kit" Moreton 2022-01-05 06:08:01 +00:00
parent 89f9ebc7b7
commit 33cf86ff9f
1 changed files with 27 additions and 7 deletions
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34
compiler/x86/aoptx86.pas
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@ -12310,14 +12310,34 @@ unit aoptx86;
GetNextInstruction(p,hp2) and
MatchInstruction(hp2,A_SETcc,A_Jcc,A_CMOVcc,[]) then
case taicpu(hp1).opcode Of
A_ADD, A_SUB, A_OR, A_XOR, A_AND:
A_ADD, A_SUB, A_OR, A_XOR, A_AND,
{ These two instructions set the zero flag if the result is zero }
A_POPCNT, A_LZCNT:
begin
if OpsEqual(taicpu(hp1).oper[1]^,taicpu(p).oper[1]^) and
{ does not work in case of overflow for G(E)/L(E)/C_O/C_NO }
{ and in case of carry for A(E)/B(E)/C/NC }
((taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) or
((taicpu(hp1).opcode <> A_ADD) and
(taicpu(hp1).opcode <> A_SUB))) then
if (
{ With POPCNT, an input of zero will set the zero flag
because the population count of zero is zero }
(taicpu(hp1).opcode = A_POPCNT) and
(taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) and
(
OpsEqual(taicpu(hp1).oper[0]^, taicpu(p).oper[1]^) or
{ Faster than going through the second half of the 'or'
condition below }
OpsEqual(taicpu(hp1).oper[1]^, taicpu(p).oper[1]^)
)
) or (
OpsEqual(taicpu(hp1).oper[1]^, taicpu(p).oper[1]^) and
{ does not work in case of overflow for G(E)/L(E)/C_O/C_NO }
{ and in case of carry for A(E)/B(E)/C/NC }
(
(taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) or
(
(taicpu(hp1).opcode <> A_ADD) and
(taicpu(hp1).opcode <> A_SUB) and
(taicpu(hp1).opcode <> A_LZCNT)
)
)
) then
begin
RemoveCurrentP(p, hp2);
Result:=true;