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Diffstat (limited to 'tcg/optimize.c')
-rw-r--r--tcg/optimize.c165
1 files changed, 144 insertions, 21 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c
index 89e2d6a3b3..7777743e88 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -655,11 +655,68 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
}
}
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):
@@ -670,28 +727,38 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
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) {
@@ -726,16 +793,36 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
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) {
- mask = temps[args[1]].mask >> temps[args[2]].val;
+ mask = (int32_t)temps[args[1]].mask >> temps[args[2]].val;
+ }
+ break;
+ case INDEX_op_sar_i64:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ mask = (int64_t)temps[args[1]].mask >> temps[args[2]].val;
+ }
+ break;
+
+ case INDEX_op_shr_i32:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ mask = (uint32_t)temps[args[1]].mask >> temps[args[2]].val;
+ }
+ break;
+ case INDEX_op_shr_i64:
+ if (temps[args[2]].state == TCG_TEMP_CONST) {
+ mask = (uint64_t)temps[args[1]].mask >> temps[args[2]].val;
}
break;
@@ -769,10 +856,40 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
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[def->nb_oargs + def->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);
s->gen_opc_buf[op_index] = op_to_movi(op);
@@ -839,6 +956,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
/* 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])) {
@@ -1140,6 +1258,11 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
} else {
for (i = 0; i < def->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++) {
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-15 09:55:55 +0000