target/arm: Use cmpsel in gen_ushl_vec
Instead of cmp+and or cmp+andc, use cmpsel. This will
be better for hosts that use predicate registers for cmp.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240912024114.1097832-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/target/arm/tcg/gengvec.c b/target/arm/tcg/gengvec.c
index 726a138..3edbf3a 100644
--- a/target/arm/tcg/gengvec.c
+++ b/target/arm/tcg/gengvec.c
@@ -1041,7 +1041,7 @@
TCGv_vec rval = tcg_temp_new_vec_matching(dst);
TCGv_vec lsh = tcg_temp_new_vec_matching(dst);
TCGv_vec rsh = tcg_temp_new_vec_matching(dst);
- TCGv_vec max;
+ TCGv_vec max, zero;
tcg_gen_neg_vec(vece, rsh, shift);
if (vece == MO_8) {
@@ -1061,23 +1061,20 @@
tcg_gen_shrv_vec(vece, rval, src, rsh);
/*
- * The choice of LT (signed) and GEU (unsigned) are biased toward
+ * The choice of GE (signed) and GEU (unsigned) are biased toward
* the instructions of the x86_64 host. For MO_8, the whole byte
* is significant so we must use an unsigned compare; otherwise we
* have already masked to a byte and so a signed compare works.
* Other tcg hosts have a full set of comparisons and do not care.
*/
+ zero = tcg_constant_vec_matching(dst, vece, 0);
max = tcg_constant_vec_matching(dst, vece, 8 << vece);
if (vece == MO_8) {
- tcg_gen_cmp_vec(TCG_COND_GEU, vece, lsh, lsh, max);
- tcg_gen_cmp_vec(TCG_COND_GEU, vece, rsh, rsh, max);
- tcg_gen_andc_vec(vece, lval, lval, lsh);
- tcg_gen_andc_vec(vece, rval, rval, rsh);
+ tcg_gen_cmpsel_vec(TCG_COND_GEU, vece, lval, lsh, max, zero, lval);
+ tcg_gen_cmpsel_vec(TCG_COND_GEU, vece, rval, rsh, max, zero, rval);
} else {
- tcg_gen_cmp_vec(TCG_COND_LT, vece, lsh, lsh, max);
- tcg_gen_cmp_vec(TCG_COND_LT, vece, rsh, rsh, max);
- tcg_gen_and_vec(vece, lval, lval, lsh);
- tcg_gen_and_vec(vece, rval, rval, rsh);
+ tcg_gen_cmpsel_vec(TCG_COND_GE, vece, lval, lsh, max, zero, lval);
+ tcg_gen_cmpsel_vec(TCG_COND_GE, vece, rval, rsh, max, zero, rval);
}
tcg_gen_or_vec(vece, dst, lval, rval);
}
@@ -1087,7 +1084,7 @@
{
static const TCGOpcode vecop_list[] = {
INDEX_op_neg_vec, INDEX_op_shlv_vec,
- INDEX_op_shrv_vec, INDEX_op_cmp_vec, 0
+ INDEX_op_shrv_vec, INDEX_op_cmpsel_vec, 0
};
static const GVecGen3 ops[4] = {
{ .fniv = gen_ushl_vec,
