target/i386: Expand eflags updates inline

The helpers for reset_rf, cli, sti, clac, stac are
completely trivial; implement them inline.

Drop some nearby #if 0 code.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/i386/helper.h

@@ -56,13 +56,8 @@ DEF_HELPER_2(syscall, void, env, int)
 DEF_HELPER_2(sysret, void, env, int)
 #endif
 DEF_HELPER_FLAGS_2(pause, TCG_CALL_NO_WG, noreturn, env, int)
-DEF_HELPER_1(reset_rf, void, env)
 DEF_HELPER_FLAGS_3(raise_interrupt, TCG_CALL_NO_WG, noreturn, env, int, int)
 DEF_HELPER_FLAGS_2(raise_exception, TCG_CALL_NO_WG, noreturn, env, int)
-DEF_HELPER_1(cli, void, env)
-DEF_HELPER_1(sti, void, env)
-DEF_HELPER_1(clac, void, env)
-DEF_HELPER_1(stac, void, env)
 DEF_HELPER_3(boundw, void, env, tl, int)
 DEF_HELPER_3(boundl, void, env, tl, int)
 

target/i386/tcg/cc_helper.c

@@ -346,44 +346,3 @@ void helper_clts(CPUX86State *env)
     env->cr[0] &= ~CR0_TS_MASK;
     env->hflags &= ~HF_TS_MASK;
 }
-
-void helper_reset_rf(CPUX86State *env)
-{
-    env->eflags &= ~RF_MASK;
-}
-
-void helper_cli(CPUX86State *env)
-{
-    env->eflags &= ~IF_MASK;
-}
-
-void helper_sti(CPUX86State *env)
-{
-    env->eflags |= IF_MASK;
-}
-
-void helper_clac(CPUX86State *env)
-{
-    env->eflags &= ~AC_MASK;
-}
-
-void helper_stac(CPUX86State *env)
-{
-    env->eflags |= AC_MASK;
-}
-
-#if 0
-/* vm86plus instructions */
-void helper_cli_vm(CPUX86State *env)
-{
-    env->eflags &= ~VIF_MASK;
-}
-
-void helper_sti_vm(CPUX86State *env)
-{
-    env->eflags |= VIF_MASK;
-    if (env->eflags & VIP_MASK) {
-        raise_exception_ra(env, EXCP0D_GPF, GETPC());
-    }
-}
-#endif

target/i386/tcg/translate.c

@@ -2746,6 +2746,26 @@ static void gen_reset_hflag(DisasContext *s, uint32_t mask)
     }
 }
 
+static void gen_set_eflags(DisasContext *s, target_ulong mask)
+{
+    TCGv t = tcg_temp_new();
+
+    tcg_gen_ld_tl(t, cpu_env, offsetof(CPUX86State, eflags));
+    tcg_gen_ori_tl(t, t, mask);
+    tcg_gen_st_tl(t, cpu_env, offsetof(CPUX86State, eflags));
+    tcg_temp_free(t);
+}
+
+static void gen_reset_eflags(DisasContext *s, target_ulong mask)
+{
+    TCGv t = tcg_temp_new();
+
+    tcg_gen_ld_tl(t, cpu_env, offsetof(CPUX86State, eflags));
+    tcg_gen_andi_tl(t, t, ~mask);
+    tcg_gen_st_tl(t, cpu_env, offsetof(CPUX86State, eflags));
+    tcg_temp_free(t);
+}
+
 /* Clear BND registers during legacy branches.  */
 static void gen_bnd_jmp(DisasContext *s)
 {
@@ -2776,7 +2796,7 @@ do_gen_eob_worker(DisasContext *s, bool inhibit, bool recheck_tf, bool jr)
     }
 
     if (s->base.tb->flags & HF_RF_MASK) {
-        gen_helper_reset_rf(cpu_env);
+        gen_reset_eflags(s, RF_MASK);
     }
     if (recheck_tf) {
         gen_helper_rechecking_single_step(cpu_env);
@@ -5502,12 +5522,12 @@ static bool disas_insn(DisasContext *s, CPUState *cpu)
 #endif
     case 0xfa: /* cli */
         if (check_iopl(s)) {
-            gen_helper_cli(cpu_env);
+            gen_reset_eflags(s, IF_MASK);
         }
         break;
     case 0xfb: /* sti */
         if (check_iopl(s)) {
-            gen_helper_sti(cpu_env);
+            gen_set_eflags(s, IF_MASK);
             /* interruptions are enabled only the first insn after sti */
             gen_update_eip_next(s);
             gen_eob_inhibit_irq(s, true);
@@ -5789,7 +5809,7 @@ static bool disas_insn(DisasContext *s, CPUState *cpu)
                 || CPL(s) != 0) {
                 goto illegal_op;
             }
-            gen_helper_clac(cpu_env);
+            gen_reset_eflags(s, AC_MASK);
             s->base.is_jmp = DISAS_EOB_NEXT;
             break;
 
@@ -5798,7 +5818,7 @@ static bool disas_insn(DisasContext *s, CPUState *cpu)
                 || CPL(s) != 0) {
                 goto illegal_op;
             }
-            gen_helper_stac(cpu_env);
+            gen_set_eflags(s, AC_MASK);
             s->base.is_jmp = DISAS_EOB_NEXT;
             break;