target/sh4: introduce DELAY_SLOT_MASK

This will make easier the introduction of a new flag in the next
patches.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

target/sh4/cpu.h

@@ -91,6 +91,7 @@
 #define FPSCR_RM_NEAREST       (0 << 0)
 #define FPSCR_RM_ZERO          (1 << 0)
 
+#define DELAY_SLOT_MASK        0x3
 #define DELAY_SLOT             (1 << 0)
 #define DELAY_SLOT_CONDITIONAL (1 << 1)
 
@@ -380,7 +381,7 @@ static inline void cpu_get_tb_cpu_state(CPUSH4State *env, target_ulong *pc,
 {
     *pc = env->pc;
     *cs_base = 0;
-    *flags = (env->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) /* Bits 0-1 */
+    *flags = (env->flags & DELAY_SLOT_MASK)                    /* Bits  0- 1 */
             | (env->fpscr & (FPSCR_FR | FPSCR_SZ | FPSCR_PR))  /* Bits 19-21 */
             | (env->sr & ((1u << SR_MD) | (1u << SR_RB)))      /* Bits 29-30 */
             | (env->sr & (1u << SR_FD))                        /* Bit 15 */

target/sh4/helper.c

@@ -172,11 +172,11 @@ void superh_cpu_do_interrupt(CPUState *cs)
     env->sgr = env->gregs[15];
     env->sr |= (1u << SR_BL) | (1u << SR_MD) | (1u << SR_RB);
 
-    if (env->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
+    if (env->flags & DELAY_SLOT_MASK) {
         /* Branch instruction should be executed again before delay slot. */
 	env->spc -= 2;
 	/* Clear flags for exception/interrupt routine. */
-        env->flags &= ~(DELAY_SLOT | DELAY_SLOT_CONDITIONAL);
+        env->flags &= ~DELAY_SLOT_MASK;
     }
 
     if (do_exp) {

target/sh4/translate.c

@@ -217,8 +217,7 @@ static inline void gen_save_cpu_state(DisasContext *ctx, bool save_pc)
     if (ctx->delayed_pc != (uint32_t) -1) {
         tcg_gen_movi_i32(cpu_delayed_pc, ctx->delayed_pc);
     }
-    if ((ctx->tbflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL))
-        != ctx->envflags) {
+    if ((ctx->tbflags & DELAY_SLOT_MASK) != ctx->envflags) {
         tcg_gen_movi_i32(cpu_flags, ctx->envflags);
     }
 }
@@ -329,7 +328,7 @@ static inline void gen_store_fpr64 (TCGv_i64 t, int reg)
 #define DREG(x) FREG(x) /* Assumes lsb of (x) is always 0 */
 
 #define CHECK_NOT_DELAY_SLOT \
-    if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {     \
+    if (ctx->envflags & DELAY_SLOT_MASK) {                           \
         gen_save_cpu_state(ctx, true);                               \
         gen_helper_raise_slot_illegal_instruction(cpu_env);          \
         ctx->bstate = BS_EXCP;                                       \
@@ -339,7 +338,7 @@ static inline void gen_store_fpr64 (TCGv_i64 t, int reg)
 #define CHECK_PRIVILEGED                                             \
     if (IS_USER(ctx)) {                                              \
         gen_save_cpu_state(ctx, true);                               \
-        if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
+        if (ctx->envflags & DELAY_SLOT_MASK) {                       \
             gen_helper_raise_slot_illegal_instruction(cpu_env);      \
         } else {                                                     \
             gen_helper_raise_illegal_instruction(cpu_env);           \
@@ -351,7 +350,7 @@ static inline void gen_store_fpr64 (TCGv_i64 t, int reg)
 #define CHECK_FPU_ENABLED                                            \
     if (ctx->tbflags & (1u << SR_FD)) {                              \
         gen_save_cpu_state(ctx, true);                               \
-        if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
+        if (ctx->envflags & DELAY_SLOT_MASK) {                       \
             gen_helper_raise_slot_fpu_disable(cpu_env);              \
         } else {                                                     \
             gen_helper_raise_fpu_disable(cpu_env);                   \
@@ -1784,7 +1783,7 @@ static void _decode_opc(DisasContext * ctx)
     fflush(stderr);
 #endif
     gen_save_cpu_state(ctx, true);
-    if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
+    if (ctx->envflags & DELAY_SLOT_MASK) {
         gen_helper_raise_slot_illegal_instruction(cpu_env);
     } else {
         gen_helper_raise_illegal_instruction(cpu_env);
@@ -1798,9 +1797,9 @@ static void decode_opc(DisasContext * ctx)
 
     _decode_opc(ctx);
 
-    if (old_flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
+    if (old_flags & DELAY_SLOT_MASK) {
         /* go out of the delay slot */
-        ctx->envflags &= ~(DELAY_SLOT | DELAY_SLOT_CONDITIONAL);
+        ctx->envflags &= ~DELAY_SLOT_MASK;
         tcg_gen_movi_i32(cpu_flags, ctx->envflags);
         ctx->bstate = BS_BRANCH;
         if (old_flags & DELAY_SLOT_CONDITIONAL) {
@@ -1824,7 +1823,7 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
     pc_start = tb->pc;
     ctx.pc = pc_start;
     ctx.tbflags = (uint32_t)tb->flags;
-    ctx.envflags = tb->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL);
+    ctx.envflags = tb->flags & DELAY_SLOT_MASK;
     ctx.bstate = BS_NONE;
     ctx.memidx = (ctx.tbflags & (1u << SR_MD)) == 0 ? 1 : 0;
     /* We don't know if the delayed pc came from a dynamic or static branch,