}
}
-static void tcg_opt_gen_mov(TCGContext *s, TCGArg *gen_args, TCGArg dst,
- TCGArg src, int nb_temps, int nb_globals)
+static void tcg_opt_gen_mov(TCGArg *gen_args, TCGArg dst, TCGArg src,
+ int nb_temps, int nb_globals)
{
reset_temp(dst, nb_temps, nb_globals);
assert(temps[src].state != TCG_TEMP_COPY);
- /* Don't try to copy if one of temps is a global or either one
- is local and another is register */
- if (src >= nb_globals && dst >= nb_globals &&
- tcg_arg_is_local(s, src) == tcg_arg_is_local(s, dst)) {
+ if (src >= nb_globals) {
assert(temps[src].state != TCG_TEMP_CONST);
if (temps[src].state != TCG_TEMP_HAS_COPY) {
temps[src].state = TCG_TEMP_HAS_COPY;
return res;
}
+static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x,
+ TCGArg y, TCGCond c)
+{
+ switch (op_bits(op)) {
+ case 32:
+ switch (c) {
+ case TCG_COND_EQ:
+ return (uint32_t)x == (uint32_t)y;
+ case TCG_COND_NE:
+ return (uint32_t)x != (uint32_t)y;
+ case TCG_COND_LT:
+ return (int32_t)x < (int32_t)y;
+ case TCG_COND_GE:
+ return (int32_t)x >= (int32_t)y;
+ case TCG_COND_LE:
+ return (int32_t)x <= (int32_t)y;
+ case TCG_COND_GT:
+ return (int32_t)x > (int32_t)y;
+ case TCG_COND_LTU:
+ return (uint32_t)x < (uint32_t)y;
+ case TCG_COND_GEU:
+ return (uint32_t)x >= (uint32_t)y;
+ case TCG_COND_LEU:
+ return (uint32_t)x <= (uint32_t)y;
+ case TCG_COND_GTU:
+ return (uint32_t)x > (uint32_t)y;
+ }
+ break;
+ case 64:
+ switch (c) {
+ case TCG_COND_EQ:
+ return (uint64_t)x == (uint64_t)y;
+ case TCG_COND_NE:
+ return (uint64_t)x != (uint64_t)y;
+ case TCG_COND_LT:
+ return (int64_t)x < (int64_t)y;
+ case TCG_COND_GE:
+ return (int64_t)x >= (int64_t)y;
+ case TCG_COND_LE:
+ return (int64_t)x <= (int64_t)y;
+ case TCG_COND_GT:
+ return (int64_t)x > (int64_t)y;
+ case TCG_COND_LTU:
+ return (uint64_t)x < (uint64_t)y;
+ case TCG_COND_GEU:
+ return (uint64_t)x >= (uint64_t)y;
+ case TCG_COND_LEU:
+ return (uint64_t)x <= (uint64_t)y;
+ case TCG_COND_GTU:
+ return (uint64_t)x > (uint64_t)y;
+ }
+ break;
+ }
+
+ fprintf(stderr,
+ "Unrecognized bitness %d or condition %d in "
+ "do_constant_folding_cond.\n", op_bits(op), c);
+ tcg_abort();
+}
+
+
/* Propagate constants and copies, fold constant expressions. */
static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
TCGArg *args, TCGOpDef *tcg_op_defs)
const TCGOpDef *def;
TCGArg *gen_args;
TCGArg tmp;
+ TCGCond cond;
+
/* Array VALS has an element for each temp.
If this temp holds a constant then its value is kept in VALS' element.
If this temp is a copy of other ones then this equivalence class'
args[2] = tmp;
}
break;
+ CASE_OP_32_64(brcond):
+ if (temps[args[0]].state == TCG_TEMP_CONST
+ && temps[args[1]].state != TCG_TEMP_CONST) {
+ tmp = args[0];
+ args[0] = args[1];
+ args[1] = tmp;
+ args[2] = tcg_swap_cond(args[2]);
+ }
+ break;
+ CASE_OP_32_64(setcond):
+ if (temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[2]].state != TCG_TEMP_CONST) {
+ tmp = args[1];
+ args[1] = args[2];
+ args[2] = tmp;
+ args[3] = tcg_swap_cond(args[3]);
+ }
+ break;
+ CASE_OP_32_64(movcond):
+ cond = args[5];
+ if (temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[2]].state != TCG_TEMP_CONST) {
+ tmp = args[1];
+ args[1] = args[2];
+ args[2] = tmp;
+ cond = tcg_swap_cond(cond);
+ }
+ /* For movcond, we canonicalize the "false" input reg to match
+ the destination reg so that the tcg backend can implement
+ a "move if true" operation. */
+ if (args[0] == args[3]) {
+ tmp = args[3];
+ args[3] = args[4];
+ args[4] = tmp;
+ cond = tcg_invert_cond(cond);
+ }
+ args[5] = cond;
default:
break;
}
- /* Simplify expression if possible. */
+ /* Simplify expressions for "shift/rot r, 0, a => movi r, 0" */
+ switch (op) {
+ CASE_OP_32_64(shl):
+ CASE_OP_32_64(shr):
+ CASE_OP_32_64(sar):
+ CASE_OP_32_64(rotl):
+ CASE_OP_32_64(rotr):
+ if (temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[1]].val == 0) {
+ gen_opc_buf[op_index] = op_to_movi(op);
+ tcg_opt_gen_movi(gen_args, args[0], 0, nb_temps, nb_globals);
+ args += 3;
+ gen_args += 2;
+ continue;
+ }
+ break;
+ default:
+ break;
+ }
+
+ /* Simplify expression for "op r, a, 0 => mov r, a" cases */
switch (op) {
CASE_OP_32_64(add):
CASE_OP_32_64(sub):
CASE_OP_32_64(sar):
CASE_OP_32_64(rotl):
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[0]].state == TCG_TEMP_COPY
&& temps[args[0]].val == args[1])
|| args[0] == args[1]) {
- args += 3;
gen_opc_buf[op_index] = INDEX_op_nop;
} else {
gen_opc_buf[op_index] = op_to_mov(op);
- tcg_opt_gen_mov(s, gen_args, args[0], args[1],
+ tcg_opt_gen_mov(gen_args, args[0], args[1],
nb_temps, nb_globals);
gen_args += 2;
- args += 3;
}
+ args += 3;
continue;
}
break;
+ default:
+ break;
+ }
+
+ /* Simplify expression for "op r, a, 0 => movi r, 0" cases */
+ switch (op) {
+ CASE_OP_32_64(and):
CASE_OP_32_64(mul):
if ((temps[args[2]].state == TCG_TEMP_CONST
&& temps[args[2]].val == 0)) {
continue;
}
break;
+ default:
+ break;
+ }
+
+ /* Simplify expression for "op r, a, a => mov r, a" cases */
+ switch (op) {
CASE_OP_32_64(or):
CASE_OP_32_64(and):
if (args[1] == args[2]) {
if (args[1] == args[0]) {
- args += 3;
gen_opc_buf[op_index] = INDEX_op_nop;
} else {
gen_opc_buf[op_index] = op_to_mov(op);
- tcg_opt_gen_mov(s, gen_args, args[0], args[1], nb_temps,
+ tcg_opt_gen_mov(gen_args, args[0], args[1], nb_temps,
nb_globals);
gen_args += 2;
- args += 3;
}
+ args += 3;
continue;
}
break;
break;
}
if (temps[args[1]].state != TCG_TEMP_CONST) {
- tcg_opt_gen_mov(s, gen_args, args[0], args[1],
+ tcg_opt_gen_mov(gen_args, args[0], args[1],
nb_temps, nb_globals);
gen_args += 2;
args += 2;
gen_opc_buf[op_index] = op_to_movi(op);
tmp = do_constant_folding(op, temps[args[1]].val, 0);
tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals);
- gen_args += 2;
- args += 2;
- break;
} else {
reset_temp(args[0], nb_temps, nb_globals);
gen_args[0] = args[0];
gen_args[1] = args[1];
- gen_args += 2;
- args += 2;
- break;
}
+ gen_args += 2;
+ args += 2;
+ break;
CASE_OP_32_64(add):
CASE_OP_32_64(sub):
CASE_OP_32_64(mul):
temps[args[2]].val);
tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals);
gen_args += 2;
- args += 3;
- break;
} else {
reset_temp(args[0], nb_temps, nb_globals);
gen_args[0] = args[0];
gen_args[1] = args[1];
gen_args[2] = args[2];
gen_args += 3;
- args += 3;
- break;
}
+ args += 3;
+ break;
+ CASE_OP_32_64(setcond):
+ if (temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST) {
+ gen_opc_buf[op_index] = op_to_movi(op);
+ tmp = do_constant_folding_cond(op, temps[args[1]].val,
+ temps[args[2]].val, args[3]);
+ tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals);
+ gen_args += 2;
+ } else {
+ reset_temp(args[0], nb_temps, nb_globals);
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args[3] = args[3];
+ gen_args += 4;
+ }
+ args += 4;
+ break;
+ CASE_OP_32_64(brcond):
+ if (temps[args[0]].state == TCG_TEMP_CONST
+ && temps[args[1]].state == TCG_TEMP_CONST) {
+ if (do_constant_folding_cond(op, temps[args[0]].val,
+ temps[args[1]].val, args[2])) {
+ memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+ gen_opc_buf[op_index] = INDEX_op_br;
+ gen_args[0] = args[3];
+ gen_args += 1;
+ } else {
+ gen_opc_buf[op_index] = INDEX_op_nop;
+ }
+ } else {
+ memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+ reset_temp(args[0], nb_temps, nb_globals);
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args[3] = args[3];
+ gen_args += 4;
+ }
+ args += 4;
+ break;
+ CASE_OP_32_64(movcond):
+ if (temps[args[1]].state == TCG_TEMP_CONST
+ && temps[args[2]].state == TCG_TEMP_CONST) {
+ tmp = do_constant_folding_cond(op, temps[args[1]].val,
+ temps[args[2]].val, args[5]);
+ if (args[0] == args[4-tmp]
+ || (temps[args[4-tmp]].state == TCG_TEMP_COPY
+ && temps[args[4-tmp]].val == args[0])) {
+ gen_opc_buf[op_index] = INDEX_op_nop;
+ } else if (temps[args[4-tmp]].state == TCG_TEMP_CONST) {
+ gen_opc_buf[op_index] = op_to_movi(op);
+ tcg_opt_gen_movi(gen_args, args[0], temps[args[4-tmp]].val,
+ nb_temps, nb_globals);
+ gen_args += 2;
+ } else {
+ gen_opc_buf[op_index] = op_to_mov(op);
+ tcg_opt_gen_mov(gen_args, args[0], args[4-tmp],
+ nb_temps, nb_globals);
+ gen_args += 2;
+ }
+ } else {
+ reset_temp(args[0], nb_temps, nb_globals);
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args[3] = args[3];
+ gen_args[4] = args[4];
+ gen_args[5] = args[5];
+ gen_args += 6;
+ }
+ args += 6;
+ break;
case INDEX_op_call:
nb_call_args = (args[0] >> 16) + (args[0] & 0xffff);
if (!(args[nb_call_args + 1] & (TCG_CALL_CONST | TCG_CALL_PURE))) {
i--;
}
break;
- case INDEX_op_set_label:
- case INDEX_op_jmp:
- case INDEX_op_br:
- CASE_OP_32_64(brcond):
- memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
- for (i = 0; i < def->nb_args; i++) {
- *gen_args = *args;
- args++;
- gen_args++;
- }
- break;
default:
/* Default case: we do know nothing about operation so no
- propagation is done. We only trash output args. */
- for (i = 0; i < def->nb_oargs; i++) {
- reset_temp(args[i], nb_temps, nb_globals);
+ propagation is done. We trash everything if the operation
+ is the end of a basic block, otherwise we only trash the
+ output args. */
+ if (def->flags & TCG_OPF_BB_END) {
+ memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+ } else {
+ for (i = 0; i < def->nb_oargs; i++) {
+ reset_temp(args[i], nb_temps, nb_globals);
+ }
}
for (i = 0; i < def->nb_args; i++) {
gen_args[i] = args[i];
projects / qemu.git / blobdiff