target/arm: Implement MVE VSHLL

Implement the MVE VHLL (vector shift left long) insn.  This has two
encodings: the T1 encoding is the usual shift-by-immediate format,
and the T2 encoding is a special case where the shift count is always
equal to the element size.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210628135835.6690-10-peter.maydell@linaro.org

target/arm/helper-mve.h

@@ -387,3 +387,12 @@ DEF_HELPER_FLAGS_4(mve_vrshli_sw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vrshli_ub, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vrshli_uh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
 DEF_HELPER_FLAGS_4(mve_vrshli_uw, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+
+DEF_HELPER_FLAGS_4(mve_vshllbsb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshllbsh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshllbub, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshllbuh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshlltsb, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshlltsh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshlltub, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)
+DEF_HELPER_FLAGS_4(mve_vshlltuh, TCG_CALL_NO_WG, void, env, ptr, ptr, i32)

target/arm/mve.decode

@@ -64,6 +64,14 @@
 @2_shl_h .... .... .. 01  shift:4 .... .... .... .... &2shift qd=%qd qm=%qm size=1
 @2_shl_w .... .... .. 1   shift:5 .... .... .... .... &2shift qd=%qd qm=%qm size=2
 
+@2_shll_b .... .... ... 01 shift:3 .... .... .... .... &2shift qd=%qd qm=%qm size=0
+@2_shll_h .... .... ... 1  shift:4 .... .... .... .... &2shift qd=%qd qm=%qm size=1
+# VSHLL encoding T2 where shift == esize
+@2_shll_esize_b .... .... .... 00 .. .... .... .... .... &2shift \
+                qd=%qd qm=%qm size=0 shift=8
+@2_shll_esize_h .... .... .... 01 .. .... .... .... .... &2shift \
+                qd=%qd qm=%qm size=1 shift=16
+
 # Right shifts are encoded as N - shift, where N is the element size in bits.
 %rshift_i5  16:5 !function=rsub_32
 %rshift_i4  16:4 !function=rsub_16
@@ -122,11 +130,35 @@ VADD             1110 1111 0 . .. ... 0 ... 0 1000 . 1 . 0 ... 0 @2op
 VSUB             1111 1111 0 . .. ... 0 ... 0 1000 . 1 . 0 ... 0 @2op
 VMUL             1110 1111 0 . .. ... 0 ... 0 1001 . 1 . 1 ... 0 @2op
 
-VMULH_S          111 0 1110 0 . .. ...1 ... 0 1110 . 0 . 0 ... 1 @2op
-VMULH_U          111 1 1110 0 . .. ...1 ... 0 1110 . 0 . 0 ... 1 @2op
+# The VSHLL T2 encoding is not a @2op pattern, but is here because it
+# overlaps what would be size=0b11 VMULH/VRMULH
+{
+  VSHLL_BS       111 0 1110 0 . 11 .. 01 ... 0 1110 0 0 . 0 ... 1 @2_shll_esize_b
+  VSHLL_BS       111 0 1110 0 . 11 .. 01 ... 0 1110 0 0 . 0 ... 1 @2_shll_esize_h
+
+  VMULH_S        111 0 1110 0 . .. ...1 ... 0 1110 . 0 . 0 ... 1 @2op
+}
+
+{
+  VSHLL_BU       111 1 1110 0 . 11 .. 01 ... 0 1110 0 0 . 0 ... 1 @2_shll_esize_b
+  VSHLL_BU       111 1 1110 0 . 11 .. 01 ... 0 1110 0 0 . 0 ... 1 @2_shll_esize_h
 
-VRMULH_S         111 0 1110 0 . .. ...1 ... 1 1110 . 0 . 0 ... 1 @2op
-VRMULH_U         111 1 1110 0 . .. ...1 ... 1 1110 . 0 . 0 ... 1 @2op
+  VMULH_U        111 1 1110 0 . .. ...1 ... 0 1110 . 0 . 0 ... 1 @2op
+}
+
+{
+  VSHLL_TS       111 0 1110 0 . 11 .. 01 ... 1 1110 0 0 . 0 ... 1 @2_shll_esize_b
+  VSHLL_TS       111 0 1110 0 . 11 .. 01 ... 1 1110 0 0 . 0 ... 1 @2_shll_esize_h
+
+  VRMULH_S       111 0 1110 0 . .. ...1 ... 1 1110 . 0 . 0 ... 1 @2op
+}
+
+{
+  VSHLL_TU       111 1 1110 0 . 11 .. 01 ... 1 1110 0 0 . 0 ... 1 @2_shll_esize_b
+  VSHLL_TU       111 1 1110 0 . 11 .. 01 ... 1 1110 0 0 . 0 ... 1 @2_shll_esize_h
+
+  VRMULH_U       111 1 1110 0 . .. ...1 ... 1 1110 . 0 . 0 ... 1 @2op
+}
 
 VMAX_S           111 0 1111 0 . .. ... 0 ... 0 0110 . 1 . 0 ... 0 @2op
 VMAX_U           111 1 1111 0 . .. ... 0 ... 0 0110 . 1 . 0 ... 0 @2op
@@ -326,3 +358,16 @@ VRSHRI_S          111 0 1111 1 . ... ... ... 0 0010 0 1 . 1 ... 0 @2_shr_w
 VRSHRI_U          111 1 1111 1 . ... ... ... 0 0010 0 1 . 1 ... 0 @2_shr_b
 VRSHRI_U          111 1 1111 1 . ... ... ... 0 0010 0 1 . 1 ... 0 @2_shr_h
 VRSHRI_U          111 1 1111 1 . ... ... ... 0 0010 0 1 . 1 ... 0 @2_shr_w
+
+# VSHLL T1 encoding; the T2 VSHLL encoding is elsewhere in this file
+VSHLL_BS          111 0 1110 1 . 1 .. ... ... 0 1111 0 1 . 0 ... 0 @2_shll_b
+VSHLL_BS          111 0 1110 1 . 1 .. ... ... 0 1111 0 1 . 0 ... 0 @2_shll_h
+
+VSHLL_BU          111 1 1110 1 . 1 .. ... ... 0 1111 0 1 . 0 ... 0 @2_shll_b
+VSHLL_BU          111 1 1110 1 . 1 .. ... ... 0 1111 0 1 . 0 ... 0 @2_shll_h
+
+VSHLL_TS          111 0 1110 1 . 1 .. ... ... 1 1111 0 1 . 0 ... 0 @2_shll_b
+VSHLL_TS          111 0 1110 1 . 1 .. ... ... 1 1111 0 1 . 0 ... 0 @2_shll_h
+
+VSHLL_TU          111 1 1110 1 . 1 .. ... ... 1 1111 0 1 . 0 ... 0 @2_shll_b
+VSHLL_TU          111 1 1110 1 . 1 .. ... ... 1 1111 0 1 . 0 ... 0 @2_shll_h

target/arm/mve_helper.c

@@ -1250,3 +1250,35 @@ DO_2SHIFT_SAT_S(vqshli_s, DO_SQSHL_OP)
 DO_2SHIFT_SAT_S(vqshlui_s, DO_SUQSHL_OP)
 DO_2SHIFT_U(vrshli_u, DO_VRSHLU)
 DO_2SHIFT_S(vrshli_s, DO_VRSHLS)
+
+/*
+ * Long shifts taking half-sized inputs from top or bottom of the input
+ * vector and producing a double-width result. ESIZE, TYPE are for
+ * the input, and LESIZE, LTYPE for the output.
+ * Unlike the normal shift helpers, we do not handle negative shift counts,
+ * because the long shift is strictly left-only.
+ */
+#define DO_VSHLL(OP, TOP, ESIZE, TYPE, LESIZE, LTYPE)                   \
+    void HELPER(glue(mve_, OP))(CPUARMState *env, void *vd,             \
+                                void *vm, uint32_t shift)               \
+    {                                                                   \
+        LTYPE *d = vd;                                                  \
+        TYPE *m = vm;                                                   \
+        uint16_t mask = mve_element_mask(env);                          \
+        unsigned le;                                                    \
+        assert(shift <= 16);                                            \
+        for (le = 0; le < 16 / LESIZE; le++, mask >>= LESIZE) {         \
+            LTYPE r = (LTYPE)m[H##ESIZE(le * 2 + TOP)] << shift;        \
+            mergemask(&d[H##LESIZE(le)], r, mask);                      \
+        }                                                               \
+        mve_advance_vpt(env);                                           \
+    }
+
+#define DO_VSHLL_ALL(OP, TOP)                                \
+    DO_VSHLL(OP##sb, TOP, 1, int8_t, 2, int16_t)             \
+    DO_VSHLL(OP##ub, TOP, 1, uint8_t, 2, uint16_t)           \
+    DO_VSHLL(OP##sh, TOP, 2, int16_t, 4, int32_t)            \
+    DO_VSHLL(OP##uh, TOP, 2, uint16_t, 4, uint32_t)          \
+
+DO_VSHLL_ALL(vshllb, false)
+DO_VSHLL_ALL(vshllt, true)

target/arm/translate-mve.c

@@ -893,3 +893,18 @@ DO_2SHIFT(VSHRI_S, vshli_s, true)
 DO_2SHIFT(VSHRI_U, vshli_u, true)
 DO_2SHIFT(VRSHRI_S, vrshli_s, true)
 DO_2SHIFT(VRSHRI_U, vrshli_u, true)
+
+#define DO_VSHLL(INSN, FN)                                      \
+    static bool trans_##INSN(DisasContext *s, arg_2shift *a)    \
+    {                                                           \
+        static MVEGenTwoOpShiftFn * const fns[] = {             \
+            gen_helper_mve_##FN##b,                             \
+            gen_helper_mve_##FN##h,                             \
+        };                                                      \
+        return do_2shift(s, a, fns[a->size], false);            \
+    }
+
+DO_VSHLL(VSHLL_BS, vshllbs)
+DO_VSHLL(VSHLL_BU, vshllbu)
+DO_VSHLL(VSHLL_TS, vshllts)
+DO_VSHLL(VSHLL_TU, vshlltu)