target/arm: Enforce alignment for VLDn/VSTn (single)

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-25-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Richard Henderson 2021-04-19 13:22:50 -07:00 committed by Peter Maydell
parent 7c68c196cf
commit 88976ff0a4
1 changed files with 42 additions and 6 deletions

View File

@ -629,6 +629,7 @@ static bool trans_VLDST_single(DisasContext *s, arg_VLDST_single *a)
int nregs = a->n + 1;
int vd = a->vd;
TCGv_i32 addr, tmp;
MemOp mop;
if (!arm_dc_feature(s, ARM_FEATURE_NEON)) {
return false;
@ -678,23 +679,58 @@ static bool trans_VLDST_single(DisasContext *s, arg_VLDST_single *a)
return true;
}
/* Pick up SCTLR settings */
mop = finalize_memop(s, a->size);
if (a->align) {
MemOp align_op;
switch (nregs) {
case 1:
/* For VLD1, use natural alignment. */
align_op = MO_ALIGN;
break;
case 2:
/* For VLD2, use double alignment. */
align_op = pow2_align(a->size + 1);
break;
case 4:
if (a->size == MO_32) {
/*
* For VLD4.32, align = 1 is double alignment, align = 2 is
* quad alignment; align = 3 is rejected above.
*/
align_op = pow2_align(a->size + a->align);
} else {
/* For VLD4.8 and VLD.16, we want quad alignment. */
align_op = pow2_align(a->size + 2);
}
break;
default:
/* For VLD3, the alignment field is zero and rejected above. */
g_assert_not_reached();
}
mop = (mop & ~MO_AMASK) | align_op;
}
tmp = tcg_temp_new_i32();
addr = tcg_temp_new_i32();
load_reg_var(s, addr, a->rn);
/*
* TODO: if we implemented alignment exceptions, we should check
* addr against the alignment encoded in a->align here.
*/
for (reg = 0; reg < nregs; reg++) {
if (a->l) {
gen_aa32_ld_i32(s, tmp, addr, get_mem_index(s), a->size);
gen_aa32_ld_internal_i32(s, tmp, addr, get_mem_index(s), mop);
neon_store_element(vd, a->reg_idx, a->size, tmp);
} else { /* Store */
neon_load_element(tmp, vd, a->reg_idx, a->size);
gen_aa32_st_i32(s, tmp, addr, get_mem_index(s), a->size);
gen_aa32_st_internal_i32(s, tmp, addr, get_mem_index(s), mop);
}
vd += a->stride;
tcg_gen_addi_i32(addr, addr, 1 << a->size);
/* Subsequent memory operations inherit alignment */
mop &= ~MO_AMASK;
}
tcg_temp_free_i32(addr);
tcg_temp_free_i32(tmp);