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@@ -74,6 +74,7 @@ unit aoptx86;
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function PostPeepholeOptMov(const p : tai) : Boolean;
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function PostPeepholeOptCmp(var p : tai) : Boolean;
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+ function PostPeepholeOptTestOr(var p : tai) : Boolean;
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procedure OptReferences;
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end;
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@@ -2683,6 +2684,99 @@ unit aoptx86;
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end;
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+ function TX86AsmOptimizer.PostPeepholeOptTestOr(var p : tai) : Boolean;
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+ var
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+ IsTestConstX : Boolean;
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+ hp1,hp2 : tai;
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+ begin
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+ Result:=false;
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+ { removes the line marked with (x) from the sequence
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+ and/or/xor/add/sub/... $x, %y
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+ test/or %y, %y | test $-1, %y (x)
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+ j(n)z _Label
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+ as the first instruction already adjusts the ZF
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+ %y operand may also be a reference }
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+ IsTestConstX:=(taicpu(p).opcode=A_TEST) and
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+ MatchOperand(taicpu(p).oper[0]^,-1);
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+ if (OpsEqual(taicpu(p).oper[0]^,taicpu(p).oper[1]^) or IsTestConstX) and
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+ GetLastInstruction(p, hp1) and
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+ (tai(hp1).typ = ait_instruction) and
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+ GetNextInstruction(p,hp2) and
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+ MatchInstruction(hp2,A_SETcc,A_Jcc,A_CMOVcc,[]) then
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+ case taicpu(hp1).opcode Of
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+ A_ADD, A_SUB, A_OR, A_XOR, A_AND:
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+ begin
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+ if OpsEqual(taicpu(hp1).oper[1]^,taicpu(p).oper[1]^) and
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+ { does not work in case of overflow for G(E)/L(E)/C_O/C_NO }
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+ { and in case of carry for A(E)/B(E)/C/NC }
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+ ((taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) or
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+ ((taicpu(hp1).opcode <> A_ADD) and
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+ (taicpu(hp1).opcode <> A_SUB))) then
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+ begin
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+ hp1 := tai(p.next);
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+ asml.remove(p);
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+ p.free;
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+ p := tai(hp1);
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+ Result:=true;
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+ end;
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+ end;
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+ A_SHL, A_SAL, A_SHR, A_SAR:
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+ begin
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+ if OpsEqual(taicpu(hp1).oper[1]^,taicpu(p).oper[1]^) and
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+ { SHL/SAL/SHR/SAR with a value of 0 do not change the flags }
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+ { therefore, it's only safe to do this optimization for }
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+ { shifts by a (nonzero) constant }
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+ (taicpu(hp1).oper[0]^.typ = top_const) and
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+ (taicpu(hp1).oper[0]^.val <> 0) and
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+ { does not work in case of overflow for G(E)/L(E)/C_O/C_NO }
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+ { and in case of carry for A(E)/B(E)/C/NC }
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+ (taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) then
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+ begin
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+ hp1 := tai(p.next);
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+ asml.remove(p);
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+ p.free;
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+ p := tai(hp1);
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+ Result:=true;
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+ end;
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+ end;
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+ A_DEC, A_INC, A_NEG:
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+ begin
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+ if OpsEqual(taicpu(hp1).oper[0]^,taicpu(p).oper[1]^) and
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+ { does not work in case of overflow for G(E)/L(E)/C_O/C_NO }
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+ { and in case of carry for A(E)/B(E)/C/NC }
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+ (taicpu(hp2).condition in [C_Z,C_NZ,C_E,C_NE]) then
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+ begin
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+ case taicpu(hp1).opcode Of
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+ A_DEC, A_INC:
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+ { replace inc/dec with add/sub 1, because inc/dec doesn't set the carry flag }
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+ begin
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+ case taicpu(hp1).opcode Of
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+ A_DEC: taicpu(hp1).opcode := A_SUB;
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+ A_INC: taicpu(hp1).opcode := A_ADD;
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+ end;
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+ taicpu(hp1).loadoper(1,taicpu(hp1).oper[0]^);
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+ taicpu(hp1).loadConst(0,1);
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+ taicpu(hp1).ops:=2;
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+ end
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+ end;
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+ hp1 := tai(p.next);
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+ asml.remove(p);
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+ p.free;
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+ p := tai(hp1);
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+ Result:=true;
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+ end;
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+ end
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+ else
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+ { change "test $-1,%reg" into "test %reg,%reg" }
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+ if IsTestConstX and (taicpu(p).oper[1]^.typ=top_reg) then
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+ taicpu(p).loadoper(0,taicpu(p).oper[1]^);
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+ end { case }
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+ { change "test $-1,%reg" into "test %reg,%reg" }
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+ else if IsTestConstX and (taicpu(p).oper[1]^.typ=top_reg) then
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+ taicpu(p).loadoper(0,taicpu(p).oper[1]^);
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+ end;
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+
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+
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procedure TX86AsmOptimizer.OptReferences;
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var
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p: tai;
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florian