return x ^ y;
case INDEX_op_shl_i32:
- return (uint32_t)x << (uint32_t)y;
+ return (uint32_t)x << (y & 31);
case INDEX_op_shl_i64:
- return (uint64_t)x << (uint64_t)y;
+ return (uint64_t)x << (y & 63);
case INDEX_op_shr_i32:
- return (uint32_t)x >> (uint32_t)y;
+ return (uint32_t)x >> (y & 31);
+ case INDEX_op_trunc_shr_i32:
case INDEX_op_shr_i64:
- return (uint64_t)x >> (uint64_t)y;
+ return (uint64_t)x >> (y & 63);
case INDEX_op_sar_i32:
- return (int32_t)x >> (int32_t)y;
+ return (int32_t)x >> (y & 31);
case INDEX_op_sar_i64:
- return (int64_t)x >> (int64_t)y;
+ return (int64_t)x >> (y & 63);
case INDEX_op_rotr_i32:
- return ror32(x, y);
+ return ror32(x, y & 31);
case INDEX_op_rotr_i64:
- return ror64(x, y);
+ return ror64(x, y & 63);
case INDEX_op_rotl_i32:
- return rol32(x, y);
+ return rol32(x, y & 31);
case INDEX_op_rotl_i64:
- return rol64(x, y);
+ return rol64(x, y & 63);
CASE_OP_32_64(not):
return ~x;
static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
TCGArg *args, TCGOpDef *tcg_op_defs)
{
- int i, nb_ops, op_index, nb_temps, nb_globals, nb_call_args;
- tcg_target_ulong mask, affected;
- TCGOpcode op;
- const TCGOpDef *def;
+ int nb_ops, op_index, nb_temps, nb_globals;
TCGArg *gen_args;
- TCGArg tmp;
/* Array VALS has an element for each temp.
If this temp holds a constant then its value is kept in VALS' element.
nb_ops = tcg_opc_ptr - s->gen_opc_buf;
gen_args = args;
for (op_index = 0; op_index < nb_ops; op_index++) {
- op = s->gen_opc_buf[op_index];
- def = &tcg_op_defs[op];
- /* Do copy propagation */
+ TCGOpcode op = s->gen_opc_buf[op_index];
+ const TCGOpDef *def = &tcg_op_defs[op];
+ tcg_target_ulong mask, affected;
+ int nb_oargs, nb_iargs, nb_args, i;
+ TCGArg tmp;
+
if (op == INDEX_op_call) {
- int nb_oargs = args[0] >> 16;
- int nb_iargs = args[0] & 0xffff;
- for (i = nb_oargs + 1; i < nb_oargs + nb_iargs + 1; i++) {
- if (temps[args[i]].state == TCG_TEMP_COPY) {
- args[i] = find_better_copy(s, args[i]);
- }
- }
+ *gen_args++ = tmp = *args++;
+ nb_oargs = tmp >> 16;
+ nb_iargs = tmp & 0xffff;
+ nb_args = nb_oargs + nb_iargs + def->nb_cargs;
} else {
- for (i = def->nb_oargs; i < def->nb_oargs + def->nb_iargs; i++) {
- if (temps[args[i]].state == TCG_TEMP_COPY) {
- args[i] = find_better_copy(s, args[i]);
- }
+ nb_oargs = def->nb_oargs;
+ nb_iargs = def->nb_iargs;
+ nb_args = def->nb_args;
+ }
+
+ /* Do copy propagation */
+ for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
+ if (temps[args[i]].state == TCG_TEMP_COPY) {
+ args[i] = find_better_copy(s, args[i]);
}
}
}
}
break;
+ CASE_OP_32_64(xor):
+ CASE_OP_32_64(nand):
+ if (temps[args[1]].state != TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST
+ && temps[args[2]].val == -1) {
+ i = 1;
+ goto try_not;
+ }
+ break;
+ CASE_OP_32_64(nor):
+ if (temps[args[1]].state != TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST
+ && temps[args[2]].val == 0) {
+ i = 1;
+ goto try_not;
+ }
+ break;
+ CASE_OP_32_64(andc):
+ if (temps[args[2]].state != TCG_TEMP_CONST
+ && temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[1]].val == -1) {
+ i = 2;
+ goto try_not;
+ }
+ break;
+ CASE_OP_32_64(orc):
+ CASE_OP_32_64(eqv):
+ if (temps[args[2]].state != TCG_TEMP_CONST
+ && temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[1]].val == 0) {
+ i = 2;
+ goto try_not;
+ }
+ break;
+ try_not:
+ {
+ TCGOpcode not_op;
+ bool have_not;
+
+ if (def->flags & TCG_OPF_64BIT) {
+ not_op = INDEX_op_not_i64;
+ have_not = TCG_TARGET_HAS_not_i64;
+ } else {
+ not_op = INDEX_op_not_i32;
+ have_not = TCG_TARGET_HAS_not_i32;
+ }
+ if (!have_not) {
+ break;
+ }
+ s->gen_opc_buf[op_index] = not_op;
+ reset_temp(args[0]);
+ gen_args[0] = args[0];
+ gen_args[1] = args[i];
+ args += 3;
+ gen_args += 2;
+ continue;
+ }
default:
break;
}
- /* Simplify expression for "op r, a, 0 => mov r, a" cases */
+ /* Simplify expression for "op r, a, const => mov r, a" cases */
switch (op) {
CASE_OP_32_64(add):
CASE_OP_32_64(sub):
CASE_OP_32_64(rotr):
CASE_OP_32_64(or):
CASE_OP_32_64(xor):
- if (temps[args[1]].state == TCG_TEMP_CONST) {
- /* Proceed with possible constant folding. */
- break;
- }
- if (temps[args[2]].state == TCG_TEMP_CONST
+ CASE_OP_32_64(andc):
+ if (temps[args[1]].state != TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST
&& temps[args[2]].val == 0) {
- if (temps_are_copies(args[0], args[1])) {
- s->gen_opc_buf[op_index] = INDEX_op_nop;
- } else {
- s->gen_opc_buf[op_index] = op_to_mov(op);
- tcg_opt_gen_mov(s, gen_args, args[0], args[1]);
- gen_args += 2;
- }
- args += 3;
- continue;
+ goto do_mov3;
+ }
+ break;
+ CASE_OP_32_64(and):
+ CASE_OP_32_64(orc):
+ CASE_OP_32_64(eqv):
+ if (temps[args[1]].state != TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST
+ && temps[args[2]].val == -1) {
+ goto do_mov3;
}
break;
+ do_mov3:
+ if (temps_are_copies(args[0], args[1])) {
+ s->gen_opc_buf[op_index] = INDEX_op_nop;
+ } else {
+ s->gen_opc_buf[op_index] = op_to_mov(op);
+ tcg_opt_gen_mov(s, gen_args, args[0], args[1]);
+ gen_args += 2;
+ }
+ args += 3;
+ continue;
default:
break;
}
- /* Simplify using known-zero bits */
+ /* Simplify using known-zero bits. Currently only ops with a single
+ output argument is supported. */
mask = -1;
affected = -1;
switch (op) {
mask = temps[args[1]].mask & mask;
break;
- CASE_OP_32_64(sar):
+ CASE_OP_32_64(andc):
+ /* Known-zeros does not imply known-ones. Therefore unless
+ args[2] is constant, we can't infer anything from it. */
if (temps[args[2]].state == TCG_TEMP_CONST) {
- mask = ((tcg_target_long)temps[args[1]].mask
- >> temps[args[2]].val);
+ mask = ~temps[args[2]].mask;
+ goto and_const;
}
+ /* But we certainly know nothing outside args[1] may be set. */
+ mask = temps[args[1]].mask;
break;
- CASE_OP_32_64(shr):
+ case INDEX_op_sar_i32:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ tmp = temps[args[2]].val & 31;
+ mask = (int32_t)temps[args[1]].mask >> tmp;
+ }
+ break;
+ case INDEX_op_sar_i64:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ tmp = temps[args[2]].val & 63;
+ mask = (int64_t)temps[args[1]].mask >> tmp;
+ }
+ break;
+
+ case INDEX_op_shr_i32:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ tmp = temps[args[2]].val & 31;
+ mask = (uint32_t)temps[args[1]].mask >> tmp;
+ }
+ break;
+ case INDEX_op_shr_i64:
if (temps[args[2]].state == TCG_TEMP_CONST) {
- mask = temps[args[1]].mask >> temps[args[2]].val;
+ tmp = temps[args[2]].val & 63;
+ mask = (uint64_t)temps[args[1]].mask >> tmp;
}
break;
+ case INDEX_op_trunc_shr_i32:
+ mask = (uint64_t)temps[args[1]].mask >> args[2];
+ break;
+
CASE_OP_32_64(shl):
if (temps[args[2]].state == TCG_TEMP_CONST) {
- mask = temps[args[1]].mask << temps[args[2]].val;
+ tmp = temps[args[2]].val & (TCG_TARGET_REG_BITS - 1);
+ mask = temps[args[1]].mask << tmp;
}
break;
break;
CASE_OP_32_64(deposit):
- tmp = ((1ull << args[4]) - 1);
- mask = ((temps[args[1]].mask & ~(tmp << args[3]))
- | ((temps[args[2]].mask & tmp) << args[3]));
+ mask = deposit64(temps[args[1]].mask, args[3], args[4],
+ temps[args[2]].mask);
break;
CASE_OP_32_64(or):
break;
CASE_OP_32_64(setcond):
+ case INDEX_op_setcond2_i32:
mask = 1;
break;
mask = temps[args[3]].mask | temps[args[4]].mask;
break;
+ CASE_OP_32_64(ld8u):
+ case INDEX_op_qemu_ld8u:
+ mask = 0xff;
+ break;
+ CASE_OP_32_64(ld16u):
+ case INDEX_op_qemu_ld16u:
+ mask = 0xffff;
+ break;
+ case INDEX_op_ld32u_i64:
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_qemu_ld32u:
+#endif
+ mask = 0xffffffffu;
+ break;
+
+ CASE_OP_32_64(qemu_ld):
+ {
+ TCGMemOp mop = args[nb_oargs + nb_iargs];
+ if (!(mop & MO_SIGN)) {
+ mask = (2ULL << ((8 << (mop & MO_SIZE)) - 1)) - 1;
+ }
+ }
+ break;
+
default:
break;
}
+ /* 32-bit ops (non 64-bit ops and non load/store ops) generate 32-bit
+ results */
+ if (!(def->flags & (TCG_OPF_CALL_CLOBBER | TCG_OPF_64BIT))) {
+ mask &= 0xffffffffu;
+ }
+
if (mask == 0) {
- assert(def->nb_oargs == 1);
+ assert(nb_oargs == 1);
s->gen_opc_buf[op_index] = op_to_movi(op);
tcg_opt_gen_movi(gen_args, args[0], 0);
- args += def->nb_oargs + def->nb_iargs + def->nb_cargs;
+ args += nb_args;
gen_args += 2;
continue;
}
if (affected == 0) {
- assert(def->nb_oargs == 1);
+ assert(nb_oargs == 1);
if (temps_are_copies(args[0], args[1])) {
s->gen_opc_buf[op_index] = INDEX_op_nop;
} else if (temps[args[1]].state != TCG_TEMP_CONST) {
tcg_opt_gen_movi(gen_args, args[0], temps[args[1]].val);
gen_args += 2;
}
- args += def->nb_iargs + 1;
+ args += nb_args;
continue;
}
/* Simplify expression for "op r, a, a => movi r, 0" cases */
switch (op) {
+ CASE_OP_32_64(andc):
CASE_OP_32_64(sub):
CASE_OP_32_64(xor):
if (temps_are_copies(args[1], args[2])) {
}
goto do_default;
+ case INDEX_op_trunc_shr_i32:
+ if (temps[args[1]].state == TCG_TEMP_CONST) {
+ s->gen_opc_buf[op_index] = op_to_movi(op);
+ tmp = do_constant_folding(op, temps[args[1]].val, args[2]);
+ tcg_opt_gen_movi(gen_args, args[0], tmp);
+ gen_args += 2;
+ args += 3;
+ break;
+ }
+ goto do_default;
+
CASE_OP_32_64(add):
CASE_OP_32_64(sub):
CASE_OP_32_64(mul):
if (temps[args[1]].state == TCG_TEMP_CONST
&& temps[args[2]].state == TCG_TEMP_CONST) {
s->gen_opc_buf[op_index] = op_to_movi(op);
- tmp = ((1ull << args[4]) - 1);
- tmp = (temps[args[1]].val & ~(tmp << args[3]))
- | ((temps[args[2]].val & tmp) << args[3]);
+ tmp = deposit64(temps[args[1]].val, args[3], args[4],
+ temps[args[2]].val);
tcg_opt_gen_movi(gen_args, args[0], tmp);
gen_args += 2;
args += 5;
tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]);
if (tmp != 2) {
if (tmp) {
+ do_brcond_true:
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_br;
gen_args[0] = args[5];
gen_args += 1;
} else {
+ do_brcond_false:
s->gen_opc_buf[op_index] = INDEX_op_nop;
}
} else if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE)
&& temps[args[3]].val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
+ do_brcond_high:
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
gen_args[0] = args[1];
gen_args[2] = args[4];
gen_args[3] = args[5];
gen_args += 4;
+ } else if (args[4] == TCG_COND_EQ) {
+ /* Simplify EQ comparisons where one of the pairs
+ can be simplified. */
+ tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
+ args[0], args[2], TCG_COND_EQ);
+ if (tmp == 0) {
+ goto do_brcond_false;
+ } else if (tmp == 1) {
+ goto do_brcond_high;
+ }
+ tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
+ args[1], args[3], TCG_COND_EQ);
+ if (tmp == 0) {
+ goto do_brcond_false;
+ } else if (tmp != 1) {
+ goto do_default;
+ }
+ do_brcond_low:
+ reset_all_temps(nb_temps);
+ s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
+ gen_args[0] = args[0];
+ gen_args[1] = args[2];
+ gen_args[2] = args[4];
+ gen_args[3] = args[5];
+ gen_args += 4;
+ } else if (args[4] == TCG_COND_NE) {
+ /* Simplify NE comparisons where one of the pairs
+ can be simplified. */
+ tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
+ args[0], args[2], TCG_COND_NE);
+ if (tmp == 0) {
+ goto do_brcond_high;
+ } else if (tmp == 1) {
+ goto do_brcond_true;
+ }
+ tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
+ args[1], args[3], TCG_COND_NE);
+ if (tmp == 0) {
+ goto do_brcond_low;
+ } else if (tmp == 1) {
+ goto do_brcond_true;
+ }
+ goto do_default;
} else {
goto do_default;
}
case INDEX_op_setcond2_i32:
tmp = do_constant_folding_cond2(&args[1], &args[3], args[5]);
if (tmp != 2) {
+ do_setcond_const:
s->gen_opc_buf[op_index] = INDEX_op_movi_i32;
tcg_opt_gen_movi(gen_args, args[0], tmp);
gen_args += 2;
&& temps[args[4]].val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
+ do_setcond_high:
s->gen_opc_buf[op_index] = INDEX_op_setcond_i32;
reset_temp(args[0]);
+ temps[args[0]].mask = 1;
gen_args[0] = args[0];
gen_args[1] = args[2];
gen_args[2] = args[4];
gen_args[3] = args[5];
gen_args += 4;
+ } else if (args[5] == TCG_COND_EQ) {
+ /* Simplify EQ comparisons where one of the pairs
+ can be simplified. */
+ tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
+ args[1], args[3], TCG_COND_EQ);
+ if (tmp == 0) {
+ goto do_setcond_const;
+ } else if (tmp == 1) {
+ goto do_setcond_high;
+ }
+ tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
+ args[2], args[4], TCG_COND_EQ);
+ if (tmp == 0) {
+ goto do_setcond_high;
+ } else if (tmp != 1) {
+ goto do_default;
+ }
+ do_setcond_low:
+ reset_temp(args[0]);
+ temps[args[0]].mask = 1;
+ s->gen_opc_buf[op_index] = INDEX_op_setcond_i32;
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[3];
+ gen_args[3] = args[5];
+ gen_args += 4;
+ } else if (args[5] == TCG_COND_NE) {
+ /* Simplify NE comparisons where one of the pairs
+ can be simplified. */
+ tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
+ args[1], args[3], TCG_COND_NE);
+ if (tmp == 0) {
+ goto do_setcond_high;
+ } else if (tmp == 1) {
+ goto do_setcond_const;
+ }
+ tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
+ args[2], args[4], TCG_COND_NE);
+ if (tmp == 0) {
+ goto do_setcond_low;
+ } else if (tmp == 1) {
+ goto do_setcond_const;
+ }
+ goto do_default;
} else {
goto do_default;
}
break;
case INDEX_op_call:
- nb_call_args = (args[0] >> 16) + (args[0] & 0xffff);
- if (!(args[nb_call_args + 1] & (TCG_CALL_NO_READ_GLOBALS |
- TCG_CALL_NO_WRITE_GLOBALS))) {
+ if (!(args[nb_oargs + nb_iargs + 1]
+ & (TCG_CALL_NO_READ_GLOBALS | TCG_CALL_NO_WRITE_GLOBALS))) {
for (i = 0; i < nb_globals; i++) {
reset_temp(i);
}
}
- for (i = 0; i < (args[0] >> 16); i++) {
- reset_temp(args[i + 1]);
- }
- i = nb_call_args + 3;
- while (i) {
- *gen_args = *args;
- args++;
- gen_args++;
- i--;
- }
- break;
+ goto do_reset_output;
default:
do_default:
if (def->flags & TCG_OPF_BB_END) {
reset_all_temps(nb_temps);
} else {
- for (i = 0; i < def->nb_oargs; i++) {
+ do_reset_output:
+ for (i = 0; i < nb_oargs; i++) {
reset_temp(args[i]);
+ /* Save the corresponding known-zero bits mask for the
+ first output argument (only one supported so far). */
+ if (i == 0) {
+ temps[args[i]].mask = mask;
+ }
}
}
- for (i = 0; i < def->nb_args; i++) {
+ for (i = 0; i < nb_args; i++) {
gen_args[i] = args[i];
}
- args += def->nb_args;
- gen_args += def->nb_args;
+ args += nb_args;
+ gen_args += nb_args;
break;
}
}
projects / qemu.git / blobdiff