diff options
Diffstat (limited to 'target/sh4')
| -rw-r--r-- | target/sh4/translate.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/target/sh4/translate.c b/target/sh4/translate.c index a4e614d0f7..385b69ef14 100644 --- a/target/sh4/translate.c +++ b/target/sh4/translate.c @@ -1869,10 +1869,17 @@ static void decode_opc(DisasContext * ctx) */ static int decode_gusa(DisasContext *ctx, CPUSH4State *env, int *pmax_insns) { + uint16_t insns[5]; + int ld_adr, ld_dst, ld_mop; + int op_dst, op_src, op_opc; + int mv_src, mt_dst, st_src, st_mop; + TCGv op_arg; + uint32_t pc = ctx->pc; uint32_t pc_end = ctx->tb->cs_base; int backup = sextract32(ctx->tbflags, GUSA_SHIFT, 8); int max_insns = (pc_end - pc) / 2; + int i; if (pc != pc_end + backup || max_insns < 2) { /* This is a malformed gUSA region. Don't do anything special, @@ -1889,6 +1896,320 @@ static int decode_gusa(DisasContext *ctx, CPUSH4State *env, int *pmax_insns) return 0; } + /* The state machine below will consume only a few insns. + If there are more than that in a region, fail now. */ + if (max_insns > ARRAY_SIZE(insns)) { + goto fail; + } + + /* Read all of the insns for the region. */ + for (i = 0; i < max_insns; ++i) { + insns[i] = cpu_lduw_code(env, pc + i * 2); + } + + ld_adr = ld_dst = ld_mop = -1; + mv_src = -1; + op_dst = op_src = op_opc = -1; + mt_dst = -1; + st_src = st_mop = -1; + TCGV_UNUSED(op_arg); + i = 0; + +#define NEXT_INSN \ + do { if (i >= max_insns) goto fail; ctx->opcode = insns[i++]; } while (0) + + /* + * Expect a load to begin the region. + */ + NEXT_INSN; + switch (ctx->opcode & 0xf00f) { + case 0x6000: /* mov.b @Rm,Rn */ + ld_mop = MO_SB; + break; + case 0x6001: /* mov.w @Rm,Rn */ + ld_mop = MO_TESW; + break; + case 0x6002: /* mov.l @Rm,Rn */ + ld_mop = MO_TESL; + break; + default: + goto fail; + } + ld_adr = B7_4; + ld_dst = B11_8; + if (ld_adr == ld_dst) { + goto fail; + } + /* Unless we see a mov, any two-operand operation must use ld_dst. */ + op_dst = ld_dst; + + /* + * Expect an optional register move. + */ + NEXT_INSN; + switch (ctx->opcode & 0xf00f) { + case 0x6003: /* mov Rm,Rn */ + /* Here we want to recognize ld_dst being saved for later consumtion, + or for another input register being copied so that ld_dst need not + be clobbered during the operation. */ + op_dst = B11_8; + mv_src = B7_4; + if (op_dst == ld_dst) { + /* Overwriting the load output. */ + goto fail; + } + if (mv_src != ld_dst) { + /* Copying a new input; constrain op_src to match the load. */ + op_src = ld_dst; + } + break; + + default: + /* Put back and re-examine as operation. */ + --i; + } + + /* + * Expect the operation. + */ + NEXT_INSN; + switch (ctx->opcode & 0xf00f) { + case 0x300c: /* add Rm,Rn */ + op_opc = INDEX_op_add_i32; + goto do_reg_op; + case 0x2009: /* and Rm,Rn */ + op_opc = INDEX_op_and_i32; + goto do_reg_op; + case 0x200a: /* xor Rm,Rn */ + op_opc = INDEX_op_xor_i32; + goto do_reg_op; + case 0x200b: /* or Rm,Rn */ + op_opc = INDEX_op_or_i32; + do_reg_op: + /* The operation register should be as expected, and the + other input cannot depend on the load. */ + if (op_dst != B11_8) { + goto fail; + } + if (op_src < 0) { + /* Unconstrainted input. */ + op_src = B7_4; + } else if (op_src == B7_4) { + /* Constrained input matched load. All operations are + commutative; "swap" them by "moving" the load output + to the (implicit) first argument and the move source + to the (explicit) second argument. */ + op_src = mv_src; + } else { + goto fail; + } + op_arg = REG(op_src); + break; + + case 0x6007: /* not Rm,Rn */ + if (ld_dst != B7_4 || mv_src >= 0) { + goto fail; + } + op_dst = B11_8; + op_opc = INDEX_op_xor_i32; + op_arg = tcg_const_i32(-1); + break; + + case 0x7000 ... 0x700f: /* add #imm,Rn */ + if (op_dst != B11_8 || mv_src >= 0) { + goto fail; + } + op_opc = INDEX_op_add_i32; + op_arg = tcg_const_i32(B7_0s); + break; + + case 0x3000: /* cmp/eq Rm,Rn */ + /* Looking for the middle of a compare-and-swap sequence, + beginning with the compare. Operands can be either order, + but with only one overlapping the load. */ + if ((ld_dst == B11_8) + (ld_dst == B7_4) != 1 || mv_src >= 0) { + goto fail; + } + op_opc = INDEX_op_setcond_i32; /* placeholder */ + op_src = (ld_dst == B11_8 ? B7_4 : B11_8); + op_arg = REG(op_src); + + NEXT_INSN; + switch (ctx->opcode & 0xff00) { + case 0x8b00: /* bf label */ + case 0x8f00: /* bf/s label */ + if (pc + (i + 1 + B7_0s) * 2 != pc_end) { + goto fail; + } + if ((ctx->opcode & 0xff00) == 0x8b00) { /* bf label */ + break; + } + /* We're looking to unconditionally modify Rn with the + result of the comparison, within the delay slot of + the branch. This is used by older gcc. */ + NEXT_INSN; + if ((ctx->opcode & 0xf0ff) == 0x0029) { /* movt Rn */ + mt_dst = B11_8; + } else { + goto fail; + } + break; + + default: + goto fail; + } + break; + + case 0x2008: /* tst Rm,Rn */ + /* Looking for a compare-and-swap against zero. */ + if (ld_dst != B11_8 || ld_dst != B7_4 || mv_src >= 0) { + goto fail; + } + op_opc = INDEX_op_setcond_i32; + op_arg = tcg_const_i32(0); + + NEXT_INSN; + if ((ctx->opcode & 0xff00) != 0x8900 /* bt label */ + || pc + (i + 1 + B7_0s) * 2 != pc_end) { + goto fail; + } + break; + + default: + /* Put back and re-examine as store. */ + --i; + } + + /* + * Expect the store. + */ + /* The store must be the last insn. */ + if (i != max_insns - 1) { + goto fail; + } + NEXT_INSN; + switch (ctx->opcode & 0xf00f) { + case 0x2000: /* mov.b Rm,@Rn */ + st_mop = MO_UB; + break; + case 0x2001: /* mov.w Rm,@Rn */ + st_mop = MO_UW; + break; + case 0x2002: /* mov.l Rm,@Rn */ + st_mop = MO_UL; + break; + default: + goto fail; + } + /* The store must match the load. */ + if (ld_adr != B11_8 || st_mop != (ld_mop & MO_SIZE)) { + goto fail; + } + st_src = B7_4; + +#undef NEXT_INSN + + /* + * Emit the operation. + */ + tcg_gen_insn_start(pc, ctx->envflags); + switch (op_opc) { + case -1: + /* No operation found. Look for exchange pattern. */ + if (st_src == ld_dst || mv_src >= 0) { + goto fail; + } + tcg_gen_atomic_xchg_i32(REG(ld_dst), REG(ld_adr), REG(st_src), + ctx->memidx, ld_mop); + break; + + case INDEX_op_add_i32: + if (op_dst != st_src) { + goto fail; + } + if (op_dst == ld_dst && st_mop == MO_UL) { + tcg_gen_atomic_add_fetch_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + } else { + tcg_gen_atomic_fetch_add_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + if (op_dst != ld_dst) { + /* Note that mop sizes < 4 cannot use add_fetch + because it won't carry into the higher bits. */ + tcg_gen_add_i32(REG(op_dst), REG(ld_dst), op_arg); + } + } + break; + + case INDEX_op_and_i32: + if (op_dst != st_src) { + goto fail; + } + if (op_dst == ld_dst) { + tcg_gen_atomic_and_fetch_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + } else { + tcg_gen_atomic_fetch_and_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + tcg_gen_and_i32(REG(op_dst), REG(ld_dst), op_arg); + } + break; + + case INDEX_op_or_i32: + if (op_dst != st_src) { + goto fail; + } + if (op_dst == ld_dst) { + tcg_gen_atomic_or_fetch_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + } else { + tcg_gen_atomic_fetch_or_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + tcg_gen_or_i32(REG(op_dst), REG(ld_dst), op_arg); + } + break; + + case INDEX_op_xor_i32: + if (op_dst != st_src) { + goto fail; + } + if (op_dst == ld_dst) { + tcg_gen_atomic_xor_fetch_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + } else { + tcg_gen_atomic_fetch_xor_i32(REG(ld_dst), REG(ld_adr), + op_arg, ctx->memidx, ld_mop); + tcg_gen_xor_i32(REG(op_dst), REG(ld_dst), op_arg); + } + break; + + case INDEX_op_setcond_i32: + if (st_src == ld_dst) { + goto fail; + } + tcg_gen_atomic_cmpxchg_i32(REG(ld_dst), REG(ld_adr), op_arg, + REG(st_src), ctx->memidx, ld_mop); + tcg_gen_setcond_i32(TCG_COND_EQ, cpu_sr_t, REG(ld_dst), op_arg); + if (mt_dst >= 0) { + tcg_gen_mov_i32(REG(mt_dst), cpu_sr_t); + } + break; + + default: + g_assert_not_reached(); + } + + /* If op_src is not a valid register, then op_arg was a constant. */ + if (op_src < 0) { + tcg_temp_free_i32(op_arg); + } + + /* The entire region has been translated. */ + ctx->envflags &= ~GUSA_MASK; + ctx->pc = pc_end; + return max_insns; + + fail: qemu_log_mask(LOG_UNIMP, "Unrecognized gUSA sequence %08x-%08x\n", pc, pc_end); |