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fix: bxor16 with 0xFFFF was wrongly optimized. #1063

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Merged
boriel merged 1 commit into from
Mar 9, 2026
Merged

fix: bxor16 with 0xFFFF was wrongly optimized. #1063

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5 changes: 0 additions & 5 deletions src/arch/z80/backend/_16bit.py
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Original file line number Diff line number Diff line change
Expand Up @@ -752,11 +752,6 @@ def bxor16(cls, ins: Quad) -> list[str]:
output.append("push hl")
return output

if op2 == 0xFFFF: # X ^ 0xFFFF = bNOT X
output.append(runtime_call(RuntimeLabel.NEGHL))
output.append("push hl")
return output

output = cls.get_oper(op1, op2)
output.append(runtime_call(RuntimeLabel.BXOR16))
output.append("push hl")
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25 changes: 5 additions & 20 deletions tests/functional/arch/zx48k/bxor16.asm
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Original file line number Diff line number Diff line change
Expand Up @@ -30,8 +30,9 @@ _b:
call .core.__BXOR16
ld a, l
ld (_b), a
ld de, 65535
ld hl, (_a)
call .core.__NEGHL
call .core.__BXOR16
ld a, l
ld (_b), a
ld hl, (_a)
Expand All @@ -42,8 +43,9 @@ _b:
call .core.__BXOR16
ld a, l
ld (_b), a
ld de, 65535
ld hl, (_a)
call .core.__NEGHL
call .core.__BXOR16
ld a, l
ld (_b), a
ld de, (_a)
Expand Down Expand Up @@ -84,22 +86,5 @@ __BXOR16:
ld l, a
ret
pop namespace
#line 46 "arch/zx48k/bxor16.bas"
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/neg16.asm"
; Negates HL value (16 bit)
push namespace core
__ABS16:
bit 7, h
ret z
__NEGHL:
ld a, l ; HL = -HL
cpl
ld l, a
ld a, h
cpl
ld h, a
inc hl
ret
pop namespace
#line 47 "arch/zx48k/bxor16.bas"
#line 48 "arch/zx48k/bxor16.bas"
END