target/arm: Hoist XSCALE_CPAR, VECLEN, VECSTRIDE in cpu_get_tb_cpu_state

We do not need to compute any of these values for M-profile.
Further, XSCALE_CPAR overlaps VECSTRIDE so obviously the two
sets must be mutually exclusive.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20191023150057.25731-10-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

target/arm/helper.c

@@ -11235,21 +11235,28 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
             }
         } else {
             flags = rebuild_hflags_a32(env, fp_el, mmu_idx);
+
+            /*
+             * Note that XSCALE_CPAR shares bits with VECSTRIDE.
+             * Note that VECLEN+VECSTRIDE are RES0 for M-profile.
+             */
+            if (arm_feature(env, ARM_FEATURE_XSCALE)) {
+                flags = FIELD_DP32(flags, TBFLAG_A32,
+                                   XSCALE_CPAR, env->cp15.c15_cpar);
+            } else {
+                flags = FIELD_DP32(flags, TBFLAG_A32, VECLEN,
+                                   env->vfp.vec_len);
+                flags = FIELD_DP32(flags, TBFLAG_A32, VECSTRIDE,
+                                   env->vfp.vec_stride);
+            }
         }
 
         flags = FIELD_DP32(flags, TBFLAG_A32, THUMB, env->thumb);
-        flags = FIELD_DP32(flags, TBFLAG_A32, VECLEN, env->vfp.vec_len);
-        flags = FIELD_DP32(flags, TBFLAG_A32, VECSTRIDE, env->vfp.vec_stride);
         flags = FIELD_DP32(flags, TBFLAG_A32, CONDEXEC, env->condexec_bits);
         if (env->vfp.xregs[ARM_VFP_FPEXC] & (1 << 30)
             || arm_el_is_aa64(env, 1) || arm_feature(env, ARM_FEATURE_M)) {
             flags = FIELD_DP32(flags, TBFLAG_A32, VFPEN, 1);
         }
-        /* Note that XSCALE_CPAR shares bits with VECSTRIDE */
-        if (arm_feature(env, ARM_FEATURE_XSCALE)) {
-            flags = FIELD_DP32(flags, TBFLAG_A32,
-                               XSCALE_CPAR, env->cp15.c15_cpar);
-        }
     }
 
     /* The SS_ACTIVE and PSTATE_SS bits correspond to the state machine