From: Laurent Vivier <laur...@vivier.eu> This instruction is needed to execute commands like "ls" or "date" (from a debian lenny m68k).
It define a new feaure, CAS, and attach this new instruction to it. Signed-off-by: Laurent Vivier <laur...@vivier.eu> --- target-m68k/cpu.h | 3 +- target-m68k/helper.c | 2 + target-m68k/translate.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 66 insertions(+), 1 deletions(-) diff --git a/target-m68k/cpu.h b/target-m68k/cpu.h index 91d3141..ae4f6fa 100644 --- a/target-m68k/cpu.h +++ b/target-m68k/cpu.h @@ -210,7 +210,8 @@ enum m68k_features { M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */ M68K_FEATURE_BCCL, /* Long conditional branches. */ M68K_FEATURE_BITFIELD, /* Bit field insns. */ - M68K_FEATURE_FPU + M68K_FEATURE_FPU, + M68K_FEATURE_CAS }; static inline int m68k_feature(CPUM68KState *env, int feature) diff --git a/target-m68k/helper.c b/target-m68k/helper.c index fd9867d..d0fc155 100644 --- a/target-m68k/helper.c +++ b/target-m68k/helper.c @@ -165,6 +165,7 @@ static int cpu_m68k_set_model(CPUM68KState *env, const char *name) m68k_set_feature(env, M68K_FEATURE_SCALED_INDEX); m68k_set_feature(env, M68K_FEATURE_LONG_MULDIV); m68k_set_feature(env, M68K_FEATURE_FPU); + m68k_set_feature(env, M68K_FEATURE_CAS); case M68K_CPUID_M68000: m68k_set_feature(env, M68K_FEATURE_M68000); m68k_set_feature(env, M68K_FEATURE_USP); @@ -210,6 +211,7 @@ static int cpu_m68k_set_model(CPUM68KState *env, const char *name) m68k_set_feature(env, M68K_FEATURE_BITFIELD); m68k_set_feature(env, M68K_FEATURE_LONG_MULDIV); m68k_set_feature(env, M68K_FEATURE_QUAD_MULDIV); + m68k_set_feature(env, M68K_FEATURE_CAS); break; } diff --git a/target-m68k/translate.c b/target-m68k/translate.c index fa67ff9..c186fe1 100644 --- a/target-m68k/translate.c +++ b/target-m68k/translate.c @@ -1371,6 +1371,67 @@ DISAS_INSN(arith_im) } } +DISAS_INSN(cas) +{ + int opsize; + TCGv dest; + TCGv tmp; + TCGv cmp; + TCGv update; + TCGv addr; + TCGv res; + uint16_t ext; + int l1, l2; + + if ((insn & 0x3f) == 0x3c) { + /* CAS2: Not yet implemented */ + gen_exception(s, s->pc - 4, EXCP_UNSUPPORTED); + } + + switch((insn >> 9) & 3) { + case 1: + opsize = OS_BYTE; + break; + case 2: + opsize = OS_WORD; + break; + case 3: + opsize = OS_LONG; + break; + default: + abort(); + } + + ext = lduw_code(s->pc); + s->pc += 2; + addr = gen_lea(s, insn, opsize); + if (IS_NULL_QREG(addr)) { + gen_addr_fault(s); + return; + } + + cmp = DREG(ext, 0); + update = DREG(ext, 6); + tmp = gen_load(s, opsize, addr, 0); + dest = tcg_temp_local_new(); + tcg_gen_mov_i32(dest, tmp); + + res = tcg_temp_new(); + tcg_gen_sub_i32(res, dest, cmp); + gen_logic_cc(s, res); + + l1 = gen_new_label(); + l2 = gen_new_label(); + + gen_jmpcc(s, 6 /* !Z */, l1); + gen_store(s, opsize, addr, update); + tcg_gen_br(l2); + gen_set_label(l1); + tcg_gen_mov_i32(cmp, dest); + gen_set_label(l2); + tcg_temp_free(dest); +} + DISAS_INSN(byterev) { TCGv reg; @@ -3660,6 +3721,7 @@ void register_m68k_insns (CPUM68KState *env) INSN(bitop_im, 0840, ffc0, M68000); INSN(bitop_im, 0880, ffc0, CF_ISA_A); INSN(bitop_im, 0880, ffc0, M68000); + INSN(cas, 08c0, f9c0, CAS); INSN(bitop_im, 08c0, ffc0, CF_ISA_A); INSN(bitop_im, 08c0, ffc0, M68000); INSN(arith_im, 0a80, fff8, CF_ISA_A); -- 1.7.2.3