diff mbox series

[11/11] target/arm: Enforce alignment for VLDn/VSTn (single)

Message ID 20201125040642.2339476-12-richard.henderson@linaro.org (mailing list archive)
State New, archived
Headers show
Series target/arm: enforce alignment | expand

Commit Message

Richard Henderson Nov. 25, 2020, 4:06 a.m. UTC
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-neon.c.inc | 39 ++++++++++++++++++++++++++-------
 1 file changed, 31 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/target/arm/translate-neon.c.inc b/target/arm/translate-neon.c.inc
index 330b5fc7b0..160dc3d755 100644
--- a/target/arm/translate-neon.c.inc
+++ b/target/arm/translate-neon.c.inc
@@ -602,6 +602,7 @@  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;
@@ -651,25 +652,47 @@  static bool trans_VLDST_single(DisasContext *s, arg_VLDST_single *a)
         return true;
     }
 
+    mop = s->be_data | a->size;
+    if (a->align) {
+        static const MemOp mop_align[] = {
+            MO_ALIGN_2, MO_ALIGN_4, MO_ALIGN_8, MO_ALIGN_16
+        };
+
+        switch (nregs) {
+        case 1:
+            mop |= MO_ALIGN;
+            break;
+        case 2:
+            mop |= mop_align[a->size];
+            break;
+        case 3:
+            /* the align field is repurposed for VLD3 */
+            break;
+        case 4:
+            mop |= mop_align[a->size + a->align];
+            break;
+        default:
+            g_assert_not_reached();
+        }
+    }
+
     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),
-                            s->be_data | a->size);
+            gen_aa32_ld_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),
-                            s->be_data | a->size);
+            gen_aa32_st_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);