target/arm: Implement MVE scatter-gather immediate forms

Implement the MVE VLDR/VSTR insns which do scatter-gather using base
addresses from Qm plus or minus an immediate offset (possibly with
writeback). Note that writeback is not predicated but it does have
to honour ECI state, so we have to add an eci_mask check to the
VSTR_SG macros (the VLDR_SG macros already needed this to be able
to distinguish "skip beat" from "set predicated element to 0").

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 63 insertions, 36 deletions

diff --git a/target/arm/mve_helper.c b/target/arm/mve_helper.c
index 2b882db..bbbaa53 100644
--- a/target/arm/mve_helper.c
+++ b/target/arm/mve_helper.c
@@ -213,7 +213,7 @@ DO_VSTR(vstrh_w, 2, stw, 4, int32_t)
  * For loads, predicated lanes are zeroed instead of retaining
  * their previous values.
  */
-#define DO_VLDR_SG(OP, LDTYPE, ESIZE, TYPE, OFFTYPE, ADDRFN)            \
+#define DO_VLDR_SG(OP, LDTYPE, ESIZE, TYPE, OFFTYPE, ADDRFN, WB)        \
     void HELPER(mve_##OP)(CPUARMState *env, void *vd, void *vm,         \
                           uint32_t base)                                \
     {                                                                   \
@@ -230,25 +230,35 @@ DO_VSTR(vstrh_w, 2, stw, 4, int32_t)
             addr = ADDRFN(base, m[H##ESIZE(e)]);                        \
             d[H##ESIZE(e)] = (mask & 1) ?                               \
                 cpu_##LDTYPE##_data_ra(env, addr, GETPC()) : 0;         \
+            if (WB) {                                                   \
+                m[H##ESIZE(e)] = addr;                                  \
+            }                                                           \
         }                                                               \
         mve_advance_vpt(env);                                           \
     }
 
 /* We know here TYPE is unsigned so always the same as the offset type */
-#define DO_VSTR_SG(OP, STTYPE, ESIZE, TYPE, ADDRFN)                     \
+#define DO_VSTR_SG(OP, STTYPE, ESIZE, TYPE, ADDRFN, WB)                 \
     void HELPER(mve_##OP)(CPUARMState *env, void *vd, void *vm,         \
                           uint32_t base)                                \
     {                                                                   \
         TYPE *d = vd;                                                   \
         TYPE *m = vm;                                                   \
         uint16_t mask = mve_element_mask(env);                          \
+        uint16_t eci_mask = mve_eci_mask(env);                          \
         unsigned e;                                                     \
         uint32_t addr;                                                  \
-        for (e = 0; e < 16 / ESIZE; e++, mask >>= ESIZE) {              \
+        for (e = 0; e < 16 / ESIZE; e++, mask >>= ESIZE, eci_mask >>= ESIZE) { \
+            if (!(eci_mask & 1)) {                                      \
+                continue;                                               \
+            }                                                           \
             addr = ADDRFN(base, m[H##ESIZE(e)]);                        \
             if (mask & 1) {                                             \
                 cpu_##STTYPE##_data_ra(env, addr, d[H##ESIZE(e)], GETPC()); \
             }                                                           \
+            if (WB) {                                                   \
+                m[H##ESIZE(e)] = addr;                                  \
+            }                                                           \
         }                                                               \
         mve_advance_vpt(env);                                           \
     }
@@ -258,8 +268,10 @@ DO_VSTR(vstrh_w, 2, stw, 4, int32_t)
  * accesses, controlled by the predicate mask for the relevant beat,
  * and with a single 32-bit offset in the first of the two Qm elements.
  * Note that for QEMU our IMPDEF AIRCR.ENDIANNESS is always 0 (little).
+ * Address writeback happens on the odd beats and updates the address
+ * stored in the even-beat element.
  */
-#define DO_VLDR64_SG(OP, ADDRFN)                                        \
+#define DO_VLDR64_SG(OP, ADDRFN, WB)                                    \
     void HELPER(mve_##OP)(CPUARMState *env, void *vd, void *vm,         \
                           uint32_t base)                                \
     {                                                                   \
@@ -276,25 +288,35 @@ DO_VSTR(vstrh_w, 2, stw, 4, int32_t)
             addr = ADDRFN(base, m[H4(e & ~1)]);                         \
             addr += 4 * (e & 1);                                        \
             d[H4(e)] = (mask & 1) ? cpu_ldl_data_ra(env, addr, GETPC()) : 0; \
+            if (WB && (e & 1)) {                                        \
+                m[H4(e & ~1)] = addr - 4;                               \
+            }                                                           \
         }                                                               \
         mve_advance_vpt(env);                                           \
     }
 
-#define DO_VSTR64_SG(OP, ADDRFN)                                        \
+#define DO_VSTR64_SG(OP, ADDRFN, WB)                                    \
     void HELPER(mve_##OP)(CPUARMState *env, void *vd, void *vm,         \
                           uint32_t base)                                \
     {                                                                   \
         uint32_t *d = vd;                                               \
         uint32_t *m = vm;                                               \
         uint16_t mask = mve_element_mask(env);                          \
+        uint16_t eci_mask = mve_eci_mask(env);                          \
         unsigned e;                                                     \
         uint32_t addr;                                                  \
-        for (e = 0; e < 16 / 4; e++, mask >>= 4) {                      \
+        for (e = 0; e < 16 / 4; e++, mask >>= 4, eci_mask >>= 4) {      \
+            if (!(eci_mask & 1)) {                                      \
+                continue;                                               \
+            }                                                           \
             addr = ADDRFN(base, m[H4(e & ~1)]);                         \
             addr += 4 * (e & 1);                                        \
             if (mask & 1) {                                             \
                 cpu_stl_data_ra(env, addr, d[H4(e)], GETPC());          \
             }                                                           \
+            if (WB && (e & 1)) {                                        \
+                m[H4(e & ~1)] = addr - 4;                               \
+            }                                                           \
         }                                                               \
         mve_advance_vpt(env);                                           \
     }
@@ -304,36 +326,41 @@ DO_VSTR(vstrh_w, 2, stw, 4, int32_t)
 #define ADDR_ADD_OSW(BASE, OFFSET) ((BASE) + ((OFFSET) << 2))
 #define ADDR_ADD_OSD(BASE, OFFSET) ((BASE) + ((OFFSET) << 3))
 
-DO_VLDR_SG(vldrb_sg_sh, ldsb, 2, int16_t, uint16_t, ADDR_ADD)
-DO_VLDR_SG(vldrb_sg_sw, ldsb, 4, int32_t, uint32_t, ADDR_ADD)
-DO_VLDR_SG(vldrh_sg_sw, ldsw, 4, int32_t, uint32_t, ADDR_ADD)
-
-DO_VLDR_SG(vldrb_sg_ub, ldub, 1, uint8_t, uint8_t, ADDR_ADD)
-DO_VLDR_SG(vldrb_sg_uh, ldub, 2, uint16_t, uint16_t, ADDR_ADD)
-DO_VLDR_SG(vldrb_sg_uw, ldub, 4, uint32_t, uint32_t, ADDR_ADD)
-DO_VLDR_SG(vldrh_sg_uh, lduw, 2, uint16_t, uint16_t, ADDR_ADD)
-DO_VLDR_SG(vldrh_sg_uw, lduw, 4, uint32_t, uint32_t, ADDR_ADD)
-DO_VLDR_SG(vldrw_sg_uw, ldl, 4, uint32_t, uint32_t, ADDR_ADD)
-DO_VLDR64_SG(vldrd_sg_ud, ADDR_ADD)
-
-DO_VLDR_SG(vldrh_sg_os_sw, ldsw, 4, int32_t, uint32_t, ADDR_ADD_OSH)
-DO_VLDR_SG(vldrh_sg_os_uh, lduw, 2, uint16_t, uint16_t, ADDR_ADD_OSH)
-DO_VLDR_SG(vldrh_sg_os_uw, lduw, 4, uint32_t, uint32_t, ADDR_ADD_OSH)
-DO_VLDR_SG(vldrw_sg_os_uw, ldl, 4, uint32_t, uint32_t, ADDR_ADD_OSW)
-DO_VLDR64_SG(vldrd_sg_os_ud, ADDR_ADD_OSD)
-
-DO_VSTR_SG(vstrb_sg_ub, stb, 1, uint8_t, ADDR_ADD)
-DO_VSTR_SG(vstrb_sg_uh, stb, 2, uint16_t, ADDR_ADD)
-DO_VSTR_SG(vstrb_sg_uw, stb, 4, uint32_t, ADDR_ADD)
-DO_VSTR_SG(vstrh_sg_uh, stw, 2, uint16_t, ADDR_ADD)
-DO_VSTR_SG(vstrh_sg_uw, stw, 4, uint32_t, ADDR_ADD)
-DO_VSTR_SG(vstrw_sg_uw, stl, 4, uint32_t, ADDR_ADD)
-DO_VSTR64_SG(vstrd_sg_ud, ADDR_ADD)
-
-DO_VSTR_SG(vstrh_sg_os_uh, stw, 2, uint16_t, ADDR_ADD_OSH)
-DO_VSTR_SG(vstrh_sg_os_uw, stw, 4, uint32_t, ADDR_ADD_OSH)
-DO_VSTR_SG(vstrw_sg_os_uw, stl, 4, uint32_t, ADDR_ADD_OSW)
-DO_VSTR64_SG(vstrd_sg_os_ud, ADDR_ADD_OSD)
+DO_VLDR_SG(vldrb_sg_sh, ldsb, 2, int16_t, uint16_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrb_sg_sw, ldsb, 4, int32_t, uint32_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrh_sg_sw, ldsw, 4, int32_t, uint32_t, ADDR_ADD, false)
+
+DO_VLDR_SG(vldrb_sg_ub, ldub, 1, uint8_t, uint8_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrb_sg_uh, ldub, 2, uint16_t, uint16_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrb_sg_uw, ldub, 4, uint32_t, uint32_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrh_sg_uh, lduw, 2, uint16_t, uint16_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrh_sg_uw, lduw, 4, uint32_t, uint32_t, ADDR_ADD, false)
+DO_VLDR_SG(vldrw_sg_uw, ldl, 4, uint32_t, uint32_t, ADDR_ADD, false)
+DO_VLDR64_SG(vldrd_sg_ud, ADDR_ADD, false)
+
+DO_VLDR_SG(vldrh_sg_os_sw, ldsw, 4, int32_t, uint32_t, ADDR_ADD_OSH, false)
+DO_VLDR_SG(vldrh_sg_os_uh, lduw, 2, uint16_t, uint16_t, ADDR_ADD_OSH, false)
+DO_VLDR_SG(vldrh_sg_os_uw, lduw, 4, uint32_t, uint32_t, ADDR_ADD_OSH, false)
+DO_VLDR_SG(vldrw_sg_os_uw, ldl, 4, uint32_t, uint32_t, ADDR_ADD_OSW, false)
+DO_VLDR64_SG(vldrd_sg_os_ud, ADDR_ADD_OSD, false)
+
+DO_VSTR_SG(vstrb_sg_ub, stb, 1, uint8_t, ADDR_ADD, false)
+DO_VSTR_SG(vstrb_sg_uh, stb, 2, uint16_t, ADDR_ADD, false)
+DO_VSTR_SG(vstrb_sg_uw, stb, 4, uint32_t, ADDR_ADD, false)
+DO_VSTR_SG(vstrh_sg_uh, stw, 2, uint16_t, ADDR_ADD, false)
+DO_VSTR_SG(vstrh_sg_uw, stw, 4, uint32_t, ADDR_ADD, false)
+DO_VSTR_SG(vstrw_sg_uw, stl, 4, uint32_t, ADDR_ADD, false)
+DO_VSTR64_SG(vstrd_sg_ud, ADDR_ADD, false)
+
+DO_VSTR_SG(vstrh_sg_os_uh, stw, 2, uint16_t, ADDR_ADD_OSH, false)
+DO_VSTR_SG(vstrh_sg_os_uw, stw, 4, uint32_t, ADDR_ADD_OSH, false)
+DO_VSTR_SG(vstrw_sg_os_uw, stl, 4, uint32_t, ADDR_ADD_OSW, false)
+DO_VSTR64_SG(vstrd_sg_os_ud, ADDR_ADD_OSD, false)
+
+DO_VLDR_SG(vldrw_sg_wb_uw, ldl, 4, uint32_t, uint32_t, ADDR_ADD, true)
+DO_VLDR64_SG(vldrd_sg_wb_ud, ADDR_ADD, true)
+DO_VSTR_SG(vstrw_sg_wb_uw, stl, 4, uint32_t, ADDR_ADD, true)
+DO_VSTR64_SG(vstrd_sg_wb_ud, ADDR_ADD, true)
 
 /*
  * The mergemask(D, R, M) macro performs the operation "*D = R" but