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optimize TST on register direct

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This commit is contained in:
Neil Webber 2024-05-17 12:03:09 -05:00
parent 6da0df526d
commit 715ff48d22
1 changed files with 6 additions and 1 deletions
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5
op00.py
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@ -169,6 +169,11 @@ def op00_56_sbc(cpu, inst, opsize=2):
def op00_57_tst(cpu, inst, opsize=2): def op00_57_tst(cpu, inst, opsize=2):
"""TST(B) (determined by opsize). Test destination.""" """TST(B) (determined by opsize). Test destination."""
dst = inst & 0o77 dst = inst & 0o77
if dst < 8:
val = cpu.r[dst]
if opsize == 1:
val &= 0o377
else:
val = cpu.operandx(dst, opsize=opsize) val = cpu.operandx(dst, opsize=opsize)
cpu.psw_n = (val & cpu.SIGN816[opsize]) cpu.psw_n = (val & cpu.SIGN816[opsize])
cpu.psw_z = (val == 0) cpu.psw_z = (val == 0)