From 88976ff0a4a8b27046df6fd05fb7be70a2f987da Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 19 Apr 2021 13:22:50 -0700 Subject: [PATCH] target/arm: Enforce alignment for VLDn/VSTn (single) Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20210419202257.161730-25-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/translate-neon.c.inc | 48 ++++++++++++++++++++++++++++----- 1 file changed, 42 insertions(+), 6 deletions(-) diff --git a/target/arm/translate-neon.c.inc b/target/arm/translate-neon.c.inc index e706c37c80..a02b8369a1 100644 --- a/target/arm/translate-neon.c.inc +++ b/target/arm/translate-neon.c.inc @@ -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);