target/alpha: Merge several flag bytes into ENV->FLAGS

The flags are arranged such that we can manipulate them either
a whole, or as individual bytes.  The computation within
cpu_get_tb_cpu_state is now reduced to a single load and mask.

Tested-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 31 insertions, 39 deletions

diff --git a/target/alpha/cpu.h b/target/alpha/cpu.h
index aa83417be1..e95be2b34b 100644
--- a/target/alpha/cpu.h
+++ b/target/alpha/cpu.h
@@ -242,13 +242,11 @@ struct CPUAlphaState {
     uint8_t fpcr_dyn_round;
     uint8_t fpcr_flush_to_zero;
 
-    /* The Internal Processor Registers.  Some of these we assume always
-       exist for use in user-mode.  */
-    uint8_t ps;
-    uint8_t intr_flag;
-    uint8_t pal_mode;
-    uint8_t fen;
+    /* Mask of PALmode, Processor State et al.  Most of this gets copied
+       into the TranslatorBlock flags and controls code generation.  */
+    uint32_t flags;
 
+    /* The high 32-bits of the processor cycle counter.  */
     uint32_t pcc_ofs;
 
     /* These pass data from the exception logic in the translator and
@@ -398,24 +396,37 @@ enum {
 };
 
 /* Processor status constants.  */
-enum {
-    /* Low 3 bits are interrupt mask level.  */
-    PS_INT_MASK = 7,
+/* Low 3 bits are interrupt mask level.  */
+#define PS_INT_MASK   7u
 
-    /* Bits 4 and 5 are the mmu mode.  The VMS PALcode uses all 4 modes;
-       The Unix PALcode only uses bit 4.  */
-    PS_USER_MODE = 8
-};
+/* Bits 4 and 5 are the mmu mode.  The VMS PALcode uses all 4 modes;
+   The Unix PALcode only uses bit 4.  */
+#define PS_USER_MODE  8u
+
+/* CPUAlphaState->flags constants.  These are layed out so that we
+   can set or reset the pieces individually by assigning to the byte,
+   or manipulated as a whole.  */
+
+#define ENV_FLAG_PAL_SHIFT    0
+#define ENV_FLAG_PS_SHIFT     8
+#define ENV_FLAG_RX_SHIFT     16
+#define ENV_FLAG_FEN_SHIFT    24
+
+#define ENV_FLAG_PAL_MODE     (1u << ENV_FLAG_PAL_SHIFT)
+#define ENV_FLAG_PS_USER      (PS_USER_MODE << ENV_FLAG_PS_SHIFT)
+#define ENV_FLAG_RX_FLAG      (1u << ENV_FLAG_RX_SHIFT)
+#define ENV_FLAG_FEN          (1u << ENV_FLAG_FEN_SHIFT)
+
+#define ENV_FLAG_TB_MASK \
+    (ENV_FLAG_PAL_MODE | ENV_FLAG_PS_USER | ENV_FLAG_FEN)
 
 static inline int cpu_mmu_index(CPUAlphaState *env, bool ifetch)
 {
-    if (env->pal_mode) {
-        return MMU_KERNEL_IDX;
-    } else if (env->ps & PS_USER_MODE) {
-        return MMU_USER_IDX;
-    } else {
-        return MMU_KERNEL_IDX;
+    int ret = env->flags & ENV_FLAG_PS_USER ? MMU_USER_IDX : MMU_KERNEL_IDX;
+    if (env->flags & ENV_FLAG_PAL_MODE) {
+        ret = MMU_KERNEL_IDX;
     }
+    return ret;
 }
 
 enum {
@@ -482,31 +493,12 @@ QEMU_NORETURN void alpha_cpu_unassigned_access(CPUState *cpu, hwaddr addr,
                                                int unused, unsigned size);
 #endif
 
-/* Bits in TB->FLAGS that control how translation is processed.  */
-enum {
-    TB_FLAGS_PAL_MODE = 1,
-    TB_FLAGS_FEN = 2,
-    TB_FLAGS_USER_MODE = 8,
-};
-
 static inline void cpu_get_tb_cpu_state(CPUAlphaState *env, target_ulong *pc,
                                         target_ulong *cs_base, uint32_t *pflags)
 {
-    int flags = 0;
-
     *pc = env->pc;
     *cs_base = 0;
-
-    if (env->pal_mode) {
-        flags = TB_FLAGS_PAL_MODE;
-    } else {
-        flags = env->ps & PS_USER_MODE;
-    }
-    if (env->fen) {
-        flags |= TB_FLAGS_FEN;
-    }
-
-    *pflags = flags;
+    *pflags = env->flags & ENV_FLAG_TB_MASK;
 }
 
 #endif /* ALPHA_CPU_H */