target/arm: Convert VFP comparison insns to decodetree

Convert the VFP comparison instructions to decodetree.

Note that comparison instructions should not honour the VFP
short-vector length and stride information: they are scalar-only
operations.  This applies to all the 2-operand instructions except
for VMOV, VABS, VNEG and VSQRT.  (In the old decoder this is
implemented via the "if (op == 15 && rn > 3) { veclen = 0; }" check.)

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

1 files changed, 75 insertions, 0 deletions

diff --git a/target/arm/translate-vfp.inc.c b/target/arm/translate-vfp.inc.c
index a7e4ae3198..ebde86210a 100644
--- a/target/arm/translate-vfp.inc.c
+++ b/target/arm/translate-vfp.inc.c
@@ -1938,3 +1938,78 @@ static bool trans_VSQRT_dp(DisasContext *s, arg_VSQRT_dp *a)
 {
     return do_vfp_2op_dp(s, gen_VSQRT_dp, a->vd, a->vm);
 }
+
+static bool trans_VCMP_sp(DisasContext *s, arg_VCMP_sp *a)
+{
+    TCGv_i32 vd, vm;
+
+    /* Vm/M bits must be zero for the Z variant */
+    if (a->z && a->vm != 0) {
+        return false;
+    }
+
+    if (!vfp_access_check(s)) {
+        return true;
+    }
+
+    vd = tcg_temp_new_i32();
+    vm = tcg_temp_new_i32();
+
+    neon_load_reg32(vd, a->vd);
+    if (a->z) {
+        tcg_gen_movi_i32(vm, 0);
+    } else {
+        neon_load_reg32(vm, a->vm);
+    }
+
+    if (a->e) {
+        gen_helper_vfp_cmpes(vd, vm, cpu_env);
+    } else {
+        gen_helper_vfp_cmps(vd, vm, cpu_env);
+    }
+
+    tcg_temp_free_i32(vd);
+    tcg_temp_free_i32(vm);
+
+    return true;
+}
+
+static bool trans_VCMP_dp(DisasContext *s, arg_VCMP_dp *a)
+{
+    TCGv_i64 vd, vm;
+
+    /* Vm/M bits must be zero for the Z variant */
+    if (a->z && a->vm != 0) {
+        return false;
+    }
+
+    /* UNDEF accesses to D16-D31 if they don't exist. */
+    if (!dc_isar_feature(aa32_fp_d32, s) && ((a->vd | a->vm) & 0x10)) {
+        return false;
+    }
+
+    if (!vfp_access_check(s)) {
+        return true;
+    }
+
+    vd = tcg_temp_new_i64();
+    vm = tcg_temp_new_i64();
+
+    neon_load_reg64(vd, a->vd);
+    if (a->z) {
+        tcg_gen_movi_i64(vm, 0);
+    } else {
+        neon_load_reg64(vm, a->vm);
+    }
+
+    if (a->e) {
+        gen_helper_vfp_cmped(vd, vm, cpu_env);
+    } else {
+        gen_helper_vfp_cmpd(vd, vm, cpu_env);
+    }
+
+    tcg_temp_free_i64(vd);
+    tcg_temp_free_i64(vm);
+
+    return true;
+}