target/arm: Implement MVE VQADD and VQSUB

Implement the MVE VQADD and VQSUB insns, which perform saturating
addition of a scalar to each element.  Note that individual bytes of
each result element are used or discarded according to the predicate
mask, but FPSCR.QC is only set if the predicate mask for the lowest
byte of the element is set.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210617121628.20116-28-peter.maydell@linaro.org

diff --git a/target/arm/helper-mve.h b/target/arm/helper-mve.h
index 1b807e1cf5fbcc3997a8b2d56a7ac68c0b629967..092efdab4754c16c514322492b60c0c6565938d5 100644 (file)
--- a/target/arm/helper-mve.h
+++ b/target/arm/helper-mve.h
@@ -173,6 +173,22 @@ DEF_HELPER_FLAGS_4(mve_vhsubu_scalarb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vhsubu_scalarh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vhsubu_scalarw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 
+DEF_HELPER_FLAGS_4(mve_vqadds_scalarb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqadds_scalarh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqadds_scalarw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+
+DEF_HELPER_FLAGS_4(mve_vqaddu_scalarb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqaddu_scalarh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqaddu_scalarw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+
+DEF_HELPER_FLAGS_4(mve_vqsubs_scalarb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqsubs_scalarh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqsubs_scalarw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+
+DEF_HELPER_FLAGS_4(mve_vqsubu_scalarb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqsubu_scalarh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vqsubu_scalarw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+
 DEF_HELPER_FLAGS_4(mve_vbrsrb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vbrsrh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vbrsrw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)

diff --git a/target/arm/mve.decode b/target/arm/mve.decode
index e189e2de6480235aec2931f58258506186aa4ec5..c85227c675a41542459c64e1c2df461a786ec966 100644 (file)
--- a/target/arm/mve.decode
+++ b/target/arm/mve.decode
@@ -167,6 +167,11 @@ VHADD_S_scalar   1110 1110 0 . .. ... 0 ... 0 1111 . 100 .... @2scalar
 VHADD_U_scalar   1111 1110 0 . .. ... 0 ... 0 1111 . 100 .... @2scalar
 VHSUB_S_scalar   1110 1110 0 . .. ... 0 ... 1 1111 . 100 .... @2scalar
 VHSUB_U_scalar   1111 1110 0 . .. ... 0 ... 1 1111 . 100 .... @2scalar
+
+VQADD_S_scalar   1110 1110 0 . .. ... 0 ... 0 1111 . 110 .... @2scalar
+VQADD_U_scalar   1111 1110 0 . .. ... 0 ... 0 1111 . 110 .... @2scalar
+VQSUB_S_scalar   1110 1110 0 . .. ... 0 ... 1 1111 . 110 .... @2scalar
+VQSUB_U_scalar   1111 1110 0 . .. ... 0 ... 1 1111 . 110 .... @2scalar
 VBRSR            1111 1110 0 . .. ... 1 ... 1 1110 . 110 .... @2scalar
 
 # Predicate operations

diff --git a/target/arm/mve_helper.c b/target/arm/mve_helper.c
index 441bc8467b02076dfa1f39092874acfa80eeb448..91139d2c0d014a2f4098c21e6250e70a7338c1e2 100644 (file)
--- a/target/arm/mve_helper.c
+++ b/target/arm/mve_helper.c
@@ -490,6 +490,33 @@ DO_2OP_U(vhaddu, do_vhadd_u)
 DO_2OP_S(vhsubs, do_vhsub_s)
 DO_2OP_U(vhsubu, do_vhsub_u)
 
+static inline int32_t do_sat_bhw(int64_t val, int64_t min, int64_t max, bool *s)
+{
+    if (val > max) {
+        *s = true;
+        return max;
+    } else if (val < min) {
+        *s = true;
+        return min;
+    }
+    return val;
+}
+
+#define DO_SQADD_B(n, m, s) do_sat_bhw((int64_t)n + m, INT8_MIN, INT8_MAX, s)
+#define DO_SQADD_H(n, m, s) do_sat_bhw((int64_t)n + m, INT16_MIN, INT16_MAX, s)
+#define DO_SQADD_W(n, m, s) do_sat_bhw((int64_t)n + m, INT32_MIN, INT32_MAX, s)
+
+#define DO_UQADD_B(n, m, s) do_sat_bhw((int64_t)n + m, 0, UINT8_MAX, s)
+#define DO_UQADD_H(n, m, s) do_sat_bhw((int64_t)n + m, 0, UINT16_MAX, s)
+#define DO_UQADD_W(n, m, s) do_sat_bhw((int64_t)n + m, 0, UINT32_MAX, s)
+
+#define DO_SQSUB_B(n, m, s) do_sat_bhw((int64_t)n - m, INT8_MIN, INT8_MAX, s)
+#define DO_SQSUB_H(n, m, s) do_sat_bhw((int64_t)n - m, INT16_MIN, INT16_MAX, s)
+#define DO_SQSUB_W(n, m, s) do_sat_bhw((int64_t)n - m, INT32_MIN, INT32_MAX, s)
+
+#define DO_UQSUB_B(n, m, s) do_sat_bhw((int64_t)n - m, 0, UINT8_MAX, s)
+#define DO_UQSUB_H(n, m, s) do_sat_bhw((int64_t)n - m, 0, UINT16_MAX, s)
+#define DO_UQSUB_W(n, m, s) do_sat_bhw((int64_t)n - m, 0, UINT32_MAX, s)
 
 #define DO_2OP_SCALAR(OP, ESIZE, TYPE, FN)                              \
     void HELPER(glue(mve_, OP))(CPUARMState *env, void *vd, void *vn,   \
@@ -505,6 +532,27 @@ DO_2OP_U(vhsubu, do_vhsub_u)
         mve_advance_vpt(env);                                           \
     }
 
+#define DO_2OP_SAT_SCALAR(OP, ESIZE, TYPE, FN)                          \
+    void HELPER(glue(mve_, OP))(CPUARMState *env, void *vd, void *vn,   \
+                                uint32_t rm)                            \
+    {                                                                   \
+        TYPE *d = vd, *n = vn;                                          \
+        TYPE m = rm;                                                    \
+        uint16_t mask = mve_element_mask(env);                          \
+        unsigned e;                                                     \
+        bool qc = false;                                                \
+        for (e = 0; e < 16 / ESIZE; e++, mask >>= ESIZE) {              \
+            bool sat = false;                                           \
+            mergemask(&d[H##ESIZE(e)], FN(n[H##ESIZE(e)], m, &sat),     \
+                      mask);                                            \
+            qc |= sat & mask & 1;                                       \
+        }                                                               \
+        if (qc) {                                                       \
+            env->vfp.qc[0] = qc;                                        \
+        }                                                               \
+        mve_advance_vpt(env);                                           \
+    }
+
 /* provide unsigned 2-op scalar helpers for all sizes */
 #define DO_2OP_SCALAR_U(OP, FN)                 \
     DO_2OP_SCALAR(OP##b, 1, uint8_t, FN)        \
@@ -523,6 +571,20 @@ DO_2OP_SCALAR_U(vhaddu_scalar, do_vhadd_u)
 DO_2OP_SCALAR_S(vhsubs_scalar, do_vhsub_s)
 DO_2OP_SCALAR_U(vhsubu_scalar, do_vhsub_u)
 
+DO_2OP_SAT_SCALAR(vqaddu_scalarb, 1, uint8_t, DO_UQADD_B)
+DO_2OP_SAT_SCALAR(vqaddu_scalarh, 2, uint16_t, DO_UQADD_H)
+DO_2OP_SAT_SCALAR(vqaddu_scalarw, 4, uint32_t, DO_UQADD_W)
+DO_2OP_SAT_SCALAR(vqadds_scalarb, 1, int8_t, DO_SQADD_B)
+DO_2OP_SAT_SCALAR(vqadds_scalarh, 2, int16_t, DO_SQADD_H)
+DO_2OP_SAT_SCALAR(vqadds_scalarw, 4, int32_t, DO_SQADD_W)
+
+DO_2OP_SAT_SCALAR(vqsubu_scalarb, 1, uint8_t, DO_UQSUB_B)
+DO_2OP_SAT_SCALAR(vqsubu_scalarh, 2, uint16_t, DO_UQSUB_H)
+DO_2OP_SAT_SCALAR(vqsubu_scalarw, 4, uint32_t, DO_UQSUB_W)
+DO_2OP_SAT_SCALAR(vqsubs_scalarb, 1, int8_t, DO_SQSUB_B)
+DO_2OP_SAT_SCALAR(vqsubs_scalarh, 2, int16_t, DO_SQSUB_H)
+DO_2OP_SAT_SCALAR(vqsubs_scalarw, 4, int32_t, DO_SQSUB_W)
+
 static inline uint32_t do_vbrsrb(uint32_t n, uint32_t m)
 {
     m &= 0xff;

diff --git a/target/arm/translate-mve.c b/target/arm/translate-mve.c
index 7c4c06e434c0d3659a5c4ea84b0dbd390dcf2f84..27c69d9c7dd3f6c191a839dabff9031d3e02a2ed 100644 (file)
--- a/target/arm/translate-mve.c
+++ b/target/arm/translate-mve.c
@@ -446,6 +446,10 @@ DO_2OP_SCALAR(VHADD_S_scalar, vhadds_scalar)
 DO_2OP_SCALAR(VHADD_U_scalar, vhaddu_scalar)
 DO_2OP_SCALAR(VHSUB_S_scalar, vhsubs_scalar)
 DO_2OP_SCALAR(VHSUB_U_scalar, vhsubu_scalar)
+DO_2OP_SCALAR(VQADD_S_scalar, vqadds_scalar)
+DO_2OP_SCALAR(VQADD_U_scalar, vqaddu_scalar)
+DO_2OP_SCALAR(VQSUB_S_scalar, vqsubs_scalar)
+DO_2OP_SCALAR(VQSUB_U_scalar, vqsubu_scalar)
 DO_2OP_SCALAR(VBRSR, vbrsr)
 
 static bool do_long_dual_acc(DisasContext *s, arg_vmlaldav *a,