From: Laurent Vivier <laur...@vivier.eu> Signed-off-by: Laurent Vivier <laur...@vivier.eu> --- target-m68k/helper.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ target-m68k/helpers.h | 1 + target-m68k/translate.c | 32 ++++++++++++++++++++++++++++++++ 3 files changed, 78 insertions(+), 0 deletions(-)
diff --git a/target-m68k/helper.c b/target-m68k/helper.c index 7d99326..0fa59c8 100644 --- a/target-m68k/helper.c +++ b/target-m68k/helper.c @@ -1324,3 +1324,48 @@ uint32_t HELPER(abcd_cc)(CPUState *env, uint32_t src, uint32_t dest) return dest; } + +uint32_t HELPER(sbcd_cc)(CPUState *env, uint32_t src, uint32_t dest) +{ + uint16_t hi, lo; + uint16_t res; + uint32_t flags; + int bcd = 0, carry = 0; + + flags = env->cc_dest; + flags &= ~(CCF_C|CCF_X); + + if (env->cc_x) + carry = 1; + + lo = (dest & 0x0f) - (src & 0x0f) - carry; + hi = (dest & 0xf0) - (src & 0xf0); + + res = hi + lo; + if (lo & 0xf0) { + res -= 0x06; + bcd = 0x06; + } + + if ((((dest & 0xff) - (src & 0xff) - carry) & 0x100) > 0xff) { + res -= 0x60; + } + + /* C and X flags: set if decimal carry, cleared otherwise */ + + if ((((dest & 0xff) - (src & 0xff) - (bcd + carry)) & 0x300) > 0xff) { + flags |= CCF_C|CCF_X; + } + + /* Z flag: cleared if nonzero */ + + if (res & 0xff) + flags &= ~CCF_Z; + + dest = (dest & 0xffffff00) | (res & 0xff); + + env->cc_x = (flags & CCF_X) != 0; + env->cc_dest = flags; + + return dest; +} diff --git a/target-m68k/helpers.h b/target-m68k/helpers.h index f299752..76d3063 100644 --- a/target-m68k/helpers.h +++ b/target-m68k/helpers.h @@ -83,4 +83,5 @@ DEF_HELPER_3(bitfield_load, i64, i32, i32, i32); DEF_HELPER_4(bitfield_store, void, i32, i32, i32, i64); DEF_HELPER_3(abcd_cc, i32, env, i32, i32); +DEF_HELPER_3(sbcd_cc, i32, env, i32, i32); #include "def-helper.h" diff --git a/target-m68k/translate.c b/target-m68k/translate.c index 231d87a..7aef2f6 100644 --- a/target-m68k/translate.c +++ b/target-m68k/translate.c @@ -1095,6 +1095,36 @@ DISAS_INSN(abcd_mem) gen_store(s, OS_BYTE, addr_dest, dest); } +DISAS_INSN(sbcd_reg) +{ + TCGv src; + TCGv dest; + + src = DREG(insn, 0); + dest = DREG(insn, 9); + gen_helper_sbcd_cc(dest, cpu_env, src, dest); +} + +DISAS_INSN(sbcd_mem) +{ + TCGv src; + TCGv addr_src; + TCGv dest; + TCGv addr_dest; + + addr_src = AREG(insn, 0); + tcg_gen_subi_i32(addr_src, addr_src, OS_BYTE); + src = gen_load(s, OS_BYTE, addr_src, 0); + + addr_dest = AREG(insn, 9); + tcg_gen_subi_i32(addr_dest, addr_dest, OS_BYTE); + dest = gen_load(s, OS_BYTE, addr_dest, 0); + + gen_helper_sbcd_cc(dest, cpu_env, src, dest); + + gen_store(s, OS_BYTE, addr_dest, dest); +} + DISAS_INSN(addsub) { TCGv reg; @@ -3909,6 +3939,8 @@ void register_m68k_insns (CPUM68KState *env) INSN(or, 8000, f000, M68000); INSN(divw, 80c0, f0c0, CF_ISA_A); INSN(divw, 80c0, f0c0, M68000); + INSN(sbcd_reg, 8100, f1f8, M68000); + INSN(sbcd_mem, 8108, f1f8, M68000); INSN(addsub, 9000, f000, CF_ISA_A); INSN(addsub, 9000, f000, M68000); INSN(undef, 90c0, f0c0, CF_ISA_A); -- 1.7.2.3