target/sh4: split ctx->flags into ctx->tbflags and ctx->envflags

There is a confusion (and not only in the SH4 target) between tb->flags,
env->flags and ctx->flags. To avoid it, split ctx->flags into
ctx->tbflags and ctx->envflags. ctx->tbflags stays unchanged during the
whole TB translation, while ctx->envflags evolves and is kept in sync
with env->flags using TCG instructions. ctx->envflags now only contains
the part that of env->flags that is contained in the TB state, i.e. the
DELAY_SLOT* flags.

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

1 files changed, 82 insertions, 79 deletions

diff --git a/target/sh4/translate.c b/target/sh4/translate.c
index c89a147..6b526a0 100644
--- a/target/sh4/translate.c
+++ b/target/sh4/translate.c
@@ -37,7 +37,8 @@ typedef struct DisasContext {
     struct TranslationBlock *tb;
     target_ulong pc;
     uint16_t opcode;
-    uint32_t flags;
+    uint32_t tbflags;    /* should stay unmodified during the TB translation */
+    uint32_t envflags;   /* should stay in sync with env->flags using TCG ops */
     int bstate;
     int memidx;
     uint32_t delayed_pc;
@@ -49,7 +50,7 @@ typedef struct DisasContext {
 #if defined(CONFIG_USER_ONLY)
 #define IS_USER(ctx) 1
 #else
-#define IS_USER(ctx) (!(ctx->flags & (1u << SR_MD)))
+#define IS_USER(ctx) (!(ctx->tbflags & (1u << SR_MD)))
 #endif
 
 enum {
@@ -317,51 +318,50 @@ static inline void gen_store_fpr64 (TCGv_i64 t, int reg)
 #define B11_8 ((ctx->opcode >> 8) & 0xf)
 #define B15_12 ((ctx->opcode >> 12) & 0xf)
 
-#define REG(x) ((x) < 8 && (ctx->flags & (1u << SR_MD))\
-                        && (ctx->flags & (1u << SR_RB))\
+#define REG(x) ((x) < 8 && (ctx->tbflags & (1u << SR_MD))\
+                        && (ctx->tbflags & (1u << SR_RB))\
                 ? (cpu_gregs[x + 16]) : (cpu_gregs[x]))
 
-#define ALTREG(x) ((x) < 8 && (!(ctx->flags & (1u << SR_MD))\
-                               || !(ctx->flags & (1u << SR_RB)))\
+#define ALTREG(x) ((x) < 8 && (!(ctx->tbflags & (1u << SR_MD))\
+                               || !(ctx->tbflags & (1u << SR_RB)))\
 		? (cpu_gregs[x + 16]) : (cpu_gregs[x]))
 
-#define FREG(x) (ctx->flags & FPSCR_FR ? (x) ^ 0x10 : (x))
+#define FREG(x) (ctx->tbflags & FPSCR_FR ? (x) ^ 0x10 : (x))
 #define XHACK(x) ((((x) & 1 ) << 4) | ((x) & 0xe))
-#define XREG(x) (ctx->flags & FPSCR_FR ? XHACK(x) ^ 0x10 : XHACK(x))
+#define XREG(x) (ctx->tbflags & FPSCR_FR ? XHACK(x) ^ 0x10 : XHACK(x))
 #define DREG(x) FREG(x) /* Assumes lsb of (x) is always 0 */
 
 #define CHECK_NOT_DELAY_SLOT \
-  if (ctx->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL))     \
-  {                                                           \
-      tcg_gen_movi_i32(cpu_pc, ctx->pc);                      \
-      gen_helper_raise_slot_illegal_instruction(cpu_env);     \
-      ctx->bstate = BS_BRANCH;                                \
-      return;                                                 \
-  }
-
-#define CHECK_PRIVILEGED                                        \
-  if (IS_USER(ctx)) {                                           \
-      tcg_gen_movi_i32(cpu_pc, ctx->pc);                        \
-      if (ctx->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
-          gen_helper_raise_slot_illegal_instruction(cpu_env);   \
-      } else {                                                  \
-          gen_helper_raise_illegal_instruction(cpu_env);        \
-      }                                                         \
-      ctx->bstate = BS_BRANCH;                                  \
-      return;                                                   \
-  }
-
-#define CHECK_FPU_ENABLED                                       \
-  if (ctx->flags & (1u << SR_FD)) {                             \
-      tcg_gen_movi_i32(cpu_pc, ctx->pc);                        \
-      if (ctx->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
-          gen_helper_raise_slot_fpu_disable(cpu_env);           \
-      } else {                                                  \
-          gen_helper_raise_fpu_disable(cpu_env);                \
-      }                                                         \
-      ctx->bstate = BS_BRANCH;                                  \
-      return;                                                   \
-  }
+    if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {     \
+        tcg_gen_movi_i32(cpu_pc, ctx->pc);                           \
+        gen_helper_raise_slot_illegal_instruction(cpu_env);          \
+        ctx->bstate = BS_BRANCH;                                     \
+        return;                                                      \
+    }
+
+#define CHECK_PRIVILEGED                                             \
+    if (IS_USER(ctx)) {                                              \
+        tcg_gen_movi_i32(cpu_pc, ctx->pc);                           \
+        if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
+            gen_helper_raise_slot_illegal_instruction(cpu_env);      \
+        } else {                                                     \
+            gen_helper_raise_illegal_instruction(cpu_env);           \
+        }                                                            \
+        ctx->bstate = BS_BRANCH;                                     \
+        return;                                                      \
+    }
+
+#define CHECK_FPU_ENABLED                                            \
+    if (ctx->tbflags & (1u << SR_FD)) {                              \
+        tcg_gen_movi_i32(cpu_pc, ctx->pc);                           \
+        if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) { \
+            gen_helper_raise_slot_fpu_disable(cpu_env);              \
+        } else {                                                     \
+            gen_helper_raise_fpu_disable(cpu_env);                   \
+        }                                                            \
+        ctx->bstate = BS_BRANCH;                                     \
+        return;                                                      \
+    }
 
 static void _decode_opc(DisasContext * ctx)
 {
@@ -409,7 +409,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0x000b:		/* rts */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_mov_i32(cpu_delayed_pc, cpu_pr);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x0028:		/* clrmac */
@@ -431,7 +431,7 @@ static void _decode_opc(DisasContext * ctx)
 	CHECK_NOT_DELAY_SLOT
         gen_write_sr(cpu_ssr);
 	tcg_gen_mov_i32(cpu_delayed_pc, cpu_spc);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x0058:		/* sets */
@@ -498,14 +498,14 @@ static void _decode_opc(DisasContext * ctx)
 	CHECK_NOT_DELAY_SLOT
 	ctx->delayed_pc = ctx->pc + 4 + B11_0s * 2;
 	tcg_gen_movi_i32(cpu_delayed_pc, ctx->delayed_pc);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	return;
     case 0xb000:		/* bsr disp */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_movi_i32(cpu_pr, ctx->pc + 4);
 	ctx->delayed_pc = ctx->pc + 4 + B11_0s * 2;
 	tcg_gen_movi_i32(cpu_delayed_pc, ctx->delayed_pc);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	return;
     }
 
@@ -939,7 +939,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf00c: /* fmov {F,D,X}Rm,{F,D,X}Rn - FPSCR: Nothing */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_SZ) {
+        if (ctx->tbflags & FPSCR_SZ) {
 	    TCGv_i64 fp = tcg_temp_new_i64();
 	    gen_load_fpr64(fp, XREG(B7_4));
 	    gen_store_fpr64(fp, XREG(B11_8));
@@ -950,7 +950,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf00a: /* fmov {F,D,X}Rm,@Rn - FPSCR: Nothing */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_SZ) {
+        if (ctx->tbflags & FPSCR_SZ) {
 	    TCGv addr_hi = tcg_temp_new();
 	    int fr = XREG(B7_4);
 	    tcg_gen_addi_i32(addr_hi, REG(B11_8), 4);
@@ -966,7 +966,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf008: /* fmov @Rm,{F,D,X}Rn - FPSCR: Nothing */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_SZ) {
+        if (ctx->tbflags & FPSCR_SZ) {
 	    TCGv addr_hi = tcg_temp_new();
 	    int fr = XREG(B11_8);
 	    tcg_gen_addi_i32(addr_hi, REG(B7_4), 4);
@@ -980,7 +980,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf009: /* fmov @Rm+,{F,D,X}Rn - FPSCR: Nothing */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_SZ) {
+        if (ctx->tbflags & FPSCR_SZ) {
 	    TCGv addr_hi = tcg_temp_new();
 	    int fr = XREG(B11_8);
 	    tcg_gen_addi_i32(addr_hi, REG(B7_4), 4);
@@ -998,7 +998,7 @@ static void _decode_opc(DisasContext * ctx)
 	CHECK_FPU_ENABLED
         TCGv addr = tcg_temp_new_i32();
         tcg_gen_subi_i32(addr, REG(B11_8), 4);
-        if (ctx->flags & FPSCR_SZ) {
+        if (ctx->tbflags & FPSCR_SZ) {
 	    int fr = XREG(B7_4);
             tcg_gen_qemu_st_i32(cpu_fregs[fr+1], addr, ctx->memidx, MO_TEUL);
 	    tcg_gen_subi_i32(addr, addr, 4);
@@ -1015,7 +1015,7 @@ static void _decode_opc(DisasContext * ctx)
 	{
 	    TCGv addr = tcg_temp_new_i32();
 	    tcg_gen_add_i32(addr, REG(B7_4), REG(0));
-            if (ctx->flags & FPSCR_SZ) {
+            if (ctx->tbflags & FPSCR_SZ) {
 		int fr = XREG(B11_8);
                 tcg_gen_qemu_ld_i32(cpu_fregs[fr], addr,
                                     ctx->memidx, MO_TEUL);
@@ -1034,7 +1034,7 @@ static void _decode_opc(DisasContext * ctx)
 	{
 	    TCGv addr = tcg_temp_new();
 	    tcg_gen_add_i32(addr, REG(B11_8), REG(0));
-            if (ctx->flags & FPSCR_SZ) {
+            if (ctx->tbflags & FPSCR_SZ) {
 		int fr = XREG(B7_4);
                 tcg_gen_qemu_ld_i32(cpu_fregs[fr], addr,
                                     ctx->memidx, MO_TEUL);
@@ -1056,7 +1056,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0xf005: /* fcmp/gt Rm,Rn - FPSCR: R[PR,Enable.V]/W[Cause,Flag] */
 	{
 	    CHECK_FPU_ENABLED
-            if (ctx->flags & FPSCR_PR) {
+            if (ctx->tbflags & FPSCR_PR) {
                 TCGv_i64 fp0, fp1;
 
 		if (ctx->opcode & 0x0110)
@@ -1125,7 +1125,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0xf00e: /* fmac FR0,RM,Rn */
         {
             CHECK_FPU_ENABLED
-            if (ctx->flags & FPSCR_PR) {
+            if (ctx->tbflags & FPSCR_PR) {
                 break; /* illegal instruction */
             } else {
                 gen_helper_fmac_FT(cpu_fregs[FREG(B11_8)], cpu_env,
@@ -1162,7 +1162,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0x8f00:		/* bf/s label */
 	CHECK_NOT_DELAY_SLOT
 	gen_branch_slot(ctx->delayed_pc = ctx->pc + 4 + B7_0s * 2, 0);
-	ctx->flags |= DELAY_SLOT_CONDITIONAL;
+        ctx->envflags |= DELAY_SLOT_CONDITIONAL;
 	return;
     case 0x8900:		/* bt label */
 	CHECK_NOT_DELAY_SLOT
@@ -1173,7 +1173,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0x8d00:		/* bt/s label */
 	CHECK_NOT_DELAY_SLOT
 	gen_branch_slot(ctx->delayed_pc = ctx->pc + 4 + B7_0s * 2, 1);
-	ctx->flags |= DELAY_SLOT_CONDITIONAL;
+        ctx->envflags |= DELAY_SLOT_CONDITIONAL;
 	return;
     case 0x8800:		/* cmp/eq #imm,R0 */
         tcg_gen_setcondi_i32(TCG_COND_EQ, cpu_sr_t, REG(0), B7_0s);
@@ -1354,14 +1354,14 @@ static void _decode_opc(DisasContext * ctx)
     case 0x0023:		/* braf Rn */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_addi_i32(cpu_delayed_pc, REG(B11_8), ctx->pc + 4);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x0003:		/* bsrf Rn */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_movi_i32(cpu_pr, ctx->pc + 4);
 	tcg_gen_add_i32(cpu_delayed_pc, REG(B11_8), cpu_pr);
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x4015:		/* cmp/pl Rn */
@@ -1377,14 +1377,14 @@ static void _decode_opc(DisasContext * ctx)
     case 0x402b:		/* jmp @Rn */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_mov_i32(cpu_delayed_pc, REG(B11_8));
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x400b:		/* jsr @Rn */
 	CHECK_NOT_DELAY_SLOT
 	tcg_gen_movi_i32(cpu_pr, ctx->pc + 4);
 	tcg_gen_mov_i32(cpu_delayed_pc, REG(B11_8));
-	ctx->flags |= DELAY_SLOT;
+        ctx->envflags |= DELAY_SLOT;
 	ctx->delayed_pc = (uint32_t) - 1;
 	return;
     case 0x400e:		/* ldc Rm,SR */
@@ -1663,7 +1663,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf02d: /* float FPUL,FRn/DRn - FPSCR: R[PR,Enable.I]/W[Cause,Flag] */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_PR) {
+        if (ctx->tbflags & FPSCR_PR) {
 	    TCGv_i64 fp;
 	    if (ctx->opcode & 0x0100)
 		break; /* illegal instruction */
@@ -1678,7 +1678,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf03d: /* ftrc FRm/DRm,FPUL - FPSCR: R[PR,Enable.V]/W[Cause,Flag] */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_PR) {
+        if (ctx->tbflags & FPSCR_PR) {
 	    TCGv_i64 fp;
 	    if (ctx->opcode & 0x0100)
 		break; /* illegal instruction */
@@ -1699,7 +1699,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf05d: /* fabs FRn/DRn */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_PR) {
+        if (ctx->tbflags & FPSCR_PR) {
 	    if (ctx->opcode & 0x0100)
 		break; /* illegal instruction */
 	    TCGv_i64 fp = tcg_temp_new_i64();
@@ -1713,7 +1713,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf06d: /* fsqrt FRn */
 	CHECK_FPU_ENABLED
-        if (ctx->flags & FPSCR_PR) {
+        if (ctx->tbflags & FPSCR_PR) {
 	    if (ctx->opcode & 0x0100)
 		break; /* illegal instruction */
 	    TCGv_i64 fp = tcg_temp_new_i64();
@@ -1731,13 +1731,13 @@ static void _decode_opc(DisasContext * ctx)
 	break;
     case 0xf08d: /* fldi0 FRn - FPSCR: R[PR] */
 	CHECK_FPU_ENABLED
-        if (!(ctx->flags & FPSCR_PR)) {
+        if (!(ctx->tbflags & FPSCR_PR)) {
 	    tcg_gen_movi_i32(cpu_fregs[FREG(B11_8)], 0);
 	}
 	return;
     case 0xf09d: /* fldi1 FRn - FPSCR: R[PR] */
 	CHECK_FPU_ENABLED
-        if (!(ctx->flags & FPSCR_PR)) {
+        if (!(ctx->tbflags & FPSCR_PR)) {
 	    tcg_gen_movi_i32(cpu_fregs[FREG(B11_8)], 0x3f800000);
 	}
 	return;
@@ -1761,7 +1761,7 @@ static void _decode_opc(DisasContext * ctx)
 	return;
     case 0xf0ed: /* fipr FVm,FVn */
         CHECK_FPU_ENABLED
-        if ((ctx->flags & FPSCR_PR) == 0) {
+        if ((ctx->tbflags & FPSCR_PR) == 0) {
             TCGv m, n;
             m = tcg_const_i32((ctx->opcode >> 8) & 3);
             n = tcg_const_i32((ctx->opcode >> 10) & 3);
@@ -1774,7 +1774,7 @@ static void _decode_opc(DisasContext * ctx)
     case 0xf0fd: /* ftrv XMTRX,FVn */
         CHECK_FPU_ENABLED
         if ((ctx->opcode & 0x0300) == 0x0100 &&
-            (ctx->flags & FPSCR_PR) == 0) {
+            (ctx->tbflags & FPSCR_PR) == 0) {
             TCGv n;
             n = tcg_const_i32((ctx->opcode >> 10) & 3);
             gen_helper_ftrv(cpu_env, n);
@@ -1789,7 +1789,7 @@ static void _decode_opc(DisasContext * ctx)
     fflush(stderr);
 #endif
     tcg_gen_movi_i32(cpu_pc, ctx->pc);
-    if (ctx->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
+    if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
         gen_helper_raise_slot_illegal_instruction(cpu_env);
     } else {
         gen_helper_raise_illegal_instruction(cpu_env);
@@ -1799,20 +1799,20 @@ static void _decode_opc(DisasContext * ctx)
 
 static void decode_opc(DisasContext * ctx)
 {
-    uint32_t old_flags = ctx->flags;
+    uint32_t old_flags = ctx->envflags;
 
     _decode_opc(ctx);
 
     if (old_flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
-        if (ctx->flags & DELAY_SLOT_CLEARME) {
+        if (ctx->envflags & DELAY_SLOT_CLEARME) {
             gen_store_flags(0);
         } else {
 	    /* go out of the delay slot */
-	    uint32_t new_flags = ctx->flags;
+            uint32_t new_flags = ctx->envflags;
 	    new_flags &= ~(DELAY_SLOT | DELAY_SLOT_CONDITIONAL);
 	    gen_store_flags(new_flags);
         }
-        ctx->flags = 0;
+        ctx->envflags = 0;
         ctx->bstate = BS_BRANCH;
         if (old_flags & DELAY_SLOT_CONDITIONAL) {
 	    gen_delayed_conditional_jump(ctx);
@@ -1823,8 +1823,9 @@ static void decode_opc(DisasContext * ctx)
     }
 
     /* go into a delay slot */
-    if (ctx->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL))
-        gen_store_flags(ctx->flags);
+    if (ctx->envflags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL)) {
+        gen_store_flags(ctx->envflags);
+    }
 }
 
 void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
@@ -1838,16 +1839,18 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
 
     pc_start = tb->pc;
     ctx.pc = pc_start;
-    ctx.flags = (uint32_t)tb->flags;
+    ctx.tbflags = (uint32_t)tb->flags;
+    ctx.envflags = tb->flags & (DELAY_SLOT | DELAY_SLOT_CONDITIONAL |
+                                DELAY_SLOT_CLEARME);
     ctx.bstate = BS_NONE;
-    ctx.memidx = (ctx.flags & (1u << SR_MD)) == 0 ? 1 : 0;
+    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,
        so assume it is a dynamic branch.  */
     ctx.delayed_pc = -1; /* use delayed pc from env pointer */
     ctx.tb = tb;
     ctx.singlestep_enabled = cs->singlestep_enabled;
     ctx.features = env->features;
-    ctx.has_movcal = (ctx.flags & TB_FLAG_PENDING_MOVCA);
+    ctx.has_movcal = (ctx.tbflags & TB_FLAG_PENDING_MOVCA);
 
     num_insns = 0;
     max_insns = tb->cflags & CF_COUNT_MASK;
@@ -1860,7 +1863,7 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
 
     gen_tb_start(tb);
     while (ctx.bstate == BS_NONE && !tcg_op_buf_full()) {
-        tcg_gen_insn_start(ctx.pc, ctx.flags);
+        tcg_gen_insn_start(ctx.pc, ctx.envflags);
         num_insns++;
 
         if (unlikely(cpu_breakpoint_test(cs, ctx.pc, BP_ANY))) {
@@ -1904,8 +1907,8 @@ void gen_intermediate_code(CPUSH4State * env, struct TranslationBlock *tb)
             /* gen_op_interrupt_restart(); */
             /* fall through */
         case BS_NONE:
-            if (ctx.flags) {
-                gen_store_flags(ctx.flags | DELAY_SLOT_CLEARME);
+            if (ctx.envflags) {
+                gen_store_flags(ctx.envflags | DELAY_SLOT_CLEARME);
 	    }
             gen_goto_tb(&ctx, 0, ctx.pc);
             break;