target/arm: Convert Neon 2-reg-scalar float multiplies to decodetree

Convert the float versions of VMLA, VMLS and VMUL in the Neon
2-reg-scalar group to decodetree.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
As noted in the comment on the WRAP_FP_FN macro, we could have
had a do_2scalar_fp() function, but for 3 insns it seemed
simpler to just do the wrapping to get hold of the fpstatus ptr.
(These are the only fp insns in the group.)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

3 files changed, 71 insertions, 34 deletions

diff --git a/target/arm/neon-dp.decode b/target/arm/neon-dp.decode
index 983747b785..cc2ee9641d 100644
--- a/target/arm/neon-dp.decode
+++ b/target/arm/neon-dp.decode
@@ -478,9 +478,12 @@ Vimm_1r          1111 001 . 1 . 000 ... .... cmode:4 0 . op:1 1 .... @1reg_imm
                  &2scalar vm=%vm_dp vn=%vn_dp vd=%vd_dp
 
     VMLA_2sc     1111 001 . 1 . .. .... .... 0000 . 1 . 0 .... @2scalar
+    VMLA_F_2sc   1111 001 . 1 . .. .... .... 0001 . 1 . 0 .... @2scalar
 
     VMLS_2sc     1111 001 . 1 . .. .... .... 0100 . 1 . 0 .... @2scalar
+    VMLS_F_2sc   1111 001 . 1 . .. .... .... 0101 . 1 . 0 .... @2scalar
 
     VMUL_2sc     1111 001 . 1 . .. .... .... 1000 . 1 . 0 .... @2scalar
+    VMUL_F_2sc   1111 001 . 1 . .. .... .... 1001 . 1 . 0 .... @2scalar
   ]
 }
diff --git a/target/arm/translate-neon.inc.c b/target/arm/translate-neon.inc.c
index 478a0dd5c1..a5c7d60bda 100644
--- a/target/arm/translate-neon.inc.c
+++ b/target/arm/translate-neon.inc.c
@@ -2481,3 +2481,68 @@ static bool trans_VMLS_2sc(DisasContext *s, arg_2scalar *a)
 
     return do_2scalar(s, a, opfn[a->size], accfn[a->size]);
 }
+
+/*
+ * Rather than have a float-specific version of do_2scalar just for
+ * three insns, we wrap a NeonGenTwoSingleOpFn to turn it into
+ * a NeonGenTwoOpFn.
+ */
+#define WRAP_FP_FN(WRAPNAME, FUNC)                              \
+    static void WRAPNAME(TCGv_i32 rd, TCGv_i32 rn, TCGv_i32 rm) \
+    {                                                           \
+        TCGv_ptr fpstatus = get_fpstatus_ptr(1);                \
+        FUNC(rd, rn, rm, fpstatus);                             \
+        tcg_temp_free_ptr(fpstatus);                            \
+    }
+
+WRAP_FP_FN(gen_VMUL_F_mul, gen_helper_vfp_muls)
+WRAP_FP_FN(gen_VMUL_F_add, gen_helper_vfp_adds)
+WRAP_FP_FN(gen_VMUL_F_sub, gen_helper_vfp_subs)
+
+static bool trans_VMUL_F_2sc(DisasContext *s, arg_2scalar *a)
+{
+    static NeonGenTwoOpFn * const opfn[] = {
+        NULL,
+        NULL, /* TODO: fp16 support */
+        gen_VMUL_F_mul,
+        NULL,
+    };
+
+    return do_2scalar(s, a, opfn[a->size], NULL);
+}
+
+static bool trans_VMLA_F_2sc(DisasContext *s, arg_2scalar *a)
+{
+    static NeonGenTwoOpFn * const opfn[] = {
+        NULL,
+        NULL, /* TODO: fp16 support */
+        gen_VMUL_F_mul,
+        NULL,
+    };
+    static NeonGenTwoOpFn * const accfn[] = {
+        NULL,
+        NULL, /* TODO: fp16 support */
+        gen_VMUL_F_add,
+        NULL,
+    };
+
+    return do_2scalar(s, a, opfn[a->size], accfn[a->size]);
+}
+
+static bool trans_VMLS_F_2sc(DisasContext *s, arg_2scalar *a)
+{
+    static NeonGenTwoOpFn * const opfn[] = {
+        NULL,
+        NULL, /* TODO: fp16 support */
+        gen_VMUL_F_mul,
+        NULL,
+    };
+    static NeonGenTwoOpFn * const accfn[] = {
+        NULL,
+        NULL, /* TODO: fp16 support */
+        gen_VMUL_F_sub,
+        NULL,
+    };
+
+    return do_2scalar(s, a, opfn[a->size], accfn[a->size]);
+}
diff --git a/target/arm/translate.c b/target/arm/translate.c
index e9cc237ef8..e4a6a38c78 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -5187,15 +5187,11 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
                 case 0: /* Integer VMLA scalar */
                 case 4: /* Integer VMLS scalar */
                 case 8: /* Integer VMUL scalar */
-                    return 1; /* handled by decodetree */
-
                 case 1: /* Float VMLA scalar */
                 case 5: /* Floating point VMLS scalar */
                 case 9: /* Floating point VMUL scalar */
-                    if (size == 1) {
-                        return 1;
-                    }
-                    /* fall through */
+                    return 1; /* handled by decodetree */
+
                 case 12: /* VQDMULH scalar */
                 case 13: /* VQRDMULH scalar */
                     if (u && ((rd | rn) & 1)) {
@@ -5212,41 +5208,14 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
                             } else {
                                 gen_helper_neon_qdmulh_s32(tmp, cpu_env, tmp, tmp2);
                             }
-                        } else if (op == 13) {
+                        } else {
                             if (size == 1) {
                                 gen_helper_neon_qrdmulh_s16(tmp, cpu_env, tmp, tmp2);
                             } else {
                                 gen_helper_neon_qrdmulh_s32(tmp, cpu_env, tmp, tmp2);
                             }
-                        } else {
-                            TCGv_ptr fpstatus = get_fpstatus_ptr(1);
-                            gen_helper_vfp_muls(tmp, tmp, tmp2, fpstatus);
-                            tcg_temp_free_ptr(fpstatus);
                         }
                         tcg_temp_free_i32(tmp2);
-                        if (op < 8) {
-                            /* Accumulate.  */
-                            tmp2 = neon_load_reg(rd, pass);
-                            switch (op) {
-                            case 1:
-                            {
-                                TCGv_ptr fpstatus = get_fpstatus_ptr(1);
-                                gen_helper_vfp_adds(tmp, tmp, tmp2, fpstatus);
-                                tcg_temp_free_ptr(fpstatus);
-                                break;
-                            }
-                            case 5:
-                            {
-                                TCGv_ptr fpstatus = get_fpstatus_ptr(1);
-                                gen_helper_vfp_subs(tmp, tmp2, tmp, fpstatus);
-                                tcg_temp_free_ptr(fpstatus);
-                                break;
-                            }
-                            default:
-                                abort();
-                            }
-                            tcg_temp_free_i32(tmp2);
-                        }
                         neon_store_reg(rd, pass, tmp);
                     }
                     break;