target/arm: Split VFM decode

Passing the raw o1 and o2 fields from the manual is less
instructive than it might be.  Do the full decode and let
the trans_* functions pass in booleans to a helper.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200224222232.13807-17-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 55 insertions, 14 deletions

diff --git a/target/arm/translate-vfp.inc.c b/target/arm/translate-vfp.inc.c
index 1964af3ea5..41aa67c133 100644
--- a/target/arm/translate-vfp.inc.c
+++ b/target/arm/translate-vfp.inc.c
@@ -1784,7 +1784,7 @@ static bool trans_VDIV_dp(DisasContext *s, arg_VDIV_dp *a)
     return do_vfp_3op_dp(s, gen_helper_vfp_divd, a->vd, a->vn, a->vm, false);
 }
 
-static bool trans_VFM_sp(DisasContext *s, arg_VFM_sp *a)
+static bool do_vfm_sp(DisasContext *s, arg_VFMA_sp *a, bool neg_n, bool neg_d)
 {
     /*
      * VFNMA : fd = muladd(-fd,  fn, fm)
@@ -1828,12 +1828,12 @@ static bool trans_VFM_sp(DisasContext *s, arg_VFM_sp *a)
 
     neon_load_reg32(vn, a->vn);
     neon_load_reg32(vm, a->vm);
-    if (a->o2) {
+    if (neg_n) {
         /* VFNMS, VFMS */
         gen_helper_vfp_negs(vn, vn);
     }
     neon_load_reg32(vd, a->vd);
-    if (a->o1 & 1) {
+    if (neg_d) {
         /* VFNMA, VFNMS */
         gen_helper_vfp_negs(vd, vd);
     }
@@ -1849,7 +1849,27 @@ static bool trans_VFM_sp(DisasContext *s, arg_VFM_sp *a)
     return true;
 }
 
-static bool trans_VFM_dp(DisasContext *s, arg_VFM_dp *a)
+static bool trans_VFMA_sp(DisasContext *s, arg_VFMA_sp *a)
+{
+    return do_vfm_sp(s, a, false, false);
+}
+
+static bool trans_VFMS_sp(DisasContext *s, arg_VFMS_sp *a)
+{
+    return do_vfm_sp(s, a, true, false);
+}
+
+static bool trans_VFNMA_sp(DisasContext *s, arg_VFNMA_sp *a)
+{
+    return do_vfm_sp(s, a, false, true);
+}
+
+static bool trans_VFNMS_sp(DisasContext *s, arg_VFNMS_sp *a)
+{
+    return do_vfm_sp(s, a, true, true);
+}
+
+static bool do_vfm_dp(DisasContext *s, arg_VFMA_dp *a, bool neg_n, bool neg_d)
 {
     /*
      * VFNMA : fd = muladd(-fd,  fn, fm)
@@ -1905,12 +1925,12 @@ static bool trans_VFM_dp(DisasContext *s, arg_VFM_dp *a)
 
     neon_load_reg64(vn, a->vn);
     neon_load_reg64(vm, a->vm);
-    if (a->o2) {
+    if (neg_n) {
         /* VFNMS, VFMS */
         gen_helper_vfp_negd(vn, vn);
     }
     neon_load_reg64(vd, a->vd);
-    if (a->o1 & 1) {
+    if (neg_d) {
         /* VFNMA, VFNMS */
         gen_helper_vfp_negd(vd, vd);
     }
@@ -1926,6 +1946,26 @@ static bool trans_VFM_dp(DisasContext *s, arg_VFM_dp *a)
     return true;
 }
 
+static bool trans_VFMA_dp(DisasContext *s, arg_VFMA_dp *a)
+{
+    return do_vfm_dp(s, a, false, false);
+}
+
+static bool trans_VFMS_dp(DisasContext *s, arg_VFMS_dp *a)
+{
+    return do_vfm_dp(s, a, true, false);
+}
+
+static bool trans_VFNMA_dp(DisasContext *s, arg_VFNMA_dp *a)
+{
+    return do_vfm_dp(s, a, false, true);
+}
+
+static bool trans_VFNMS_dp(DisasContext *s, arg_VFNMS_dp *a)
+{
+    return do_vfm_dp(s, a, true, true);
+}
+
 static bool trans_VMOV_imm_sp(DisasContext *s, arg_VMOV_imm_sp *a)
 {
     uint32_t delta_d = 0;
diff --git a/target/arm/vfp.decode b/target/arm/vfp.decode
index 4f294f88be..5fd70f975a 100644
--- a/target/arm/vfp.decode
+++ b/target/arm/vfp.decode
@@ -130,14 +130,15 @@ VSUB_dp      ---- 1110 0.11 .... .... 1011 .1.0 ....        @vfp_dnm_d
 VDIV_sp      ---- 1110 1.00 .... .... 1010 .0.0 ....        @vfp_dnm_s
 VDIV_dp      ---- 1110 1.00 .... .... 1011 .0.0 ....        @vfp_dnm_d
 
-VFM_sp       ---- 1110 1.01 .... .... 1010 . o2:1 . 0 .... \
-             vm=%vm_sp vn=%vn_sp vd=%vd_sp o1=1
-VFM_dp       ---- 1110 1.01 .... .... 1011 . o2:1 . 0 .... \
-             vm=%vm_dp vn=%vn_dp vd=%vd_dp o1=1
-VFM_sp       ---- 1110 1.10 .... .... 1010 . o2:1 . 0 .... \
-             vm=%vm_sp vn=%vn_sp vd=%vd_sp o1=2
-VFM_dp       ---- 1110 1.10 .... .... 1011 . o2:1 . 0 .... \
-             vm=%vm_dp vn=%vn_dp vd=%vd_dp o1=2
+VFMA_sp      ---- 1110 1.10 .... .... 1010 .0. 0 ....       @vfp_dnm_s
+VFMS_sp      ---- 1110 1.10 .... .... 1010 .1. 0 ....       @vfp_dnm_s
+VFNMA_sp     ---- 1110 1.01 .... .... 1010 .0. 0 ....       @vfp_dnm_s
+VFNMS_sp     ---- 1110 1.01 .... .... 1010 .1. 0 ....       @vfp_dnm_s
+
+VFMA_dp      ---- 1110 1.10 .... .... 1011 .0.0 ....        @vfp_dnm_d
+VFMS_dp      ---- 1110 1.10 .... .... 1011 .1.0 ....        @vfp_dnm_d
+VFNMA_dp     ---- 1110 1.01 .... .... 1011 .0.0 ....        @vfp_dnm_d
+VFNMS_dp     ---- 1110 1.01 .... .... 1011 .1.0 ....        @vfp_dnm_d
 
 VMOV_imm_sp  ---- 1110 1.11 .... .... 1010 0000 .... \
              vd=%vd_sp imm=%vmov_imm