target-m68k: switch to AREG0 free mode

Add an explicit CPUState parameter instead of relying on AREG0
and switch to AREG0 free mode.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

configure

@@ -3874,7 +3874,7 @@ symlink "$source_path/Makefile.target" "$target_dir/Makefile"
 
 
 case "$target_arch2" in
-  alpha | i386 | lm32 | or32 | s390x | sparc* | x86_64 | xtensa* | ppc*)
+  alpha | i386 | lm32 | m68k | or32 | s390x | sparc* | x86_64 | xtensa* | ppc*)
     echo "CONFIG_TCG_PASS_AREG0=y" >> $config_target_mak
   ;;
 esac

target-m68k/Makefile.objs

@@ -1,5 +1,3 @@
 obj-y += m68k-semi.o
 obj-y += translate.o op_helper.o helper.o cpu.o
 obj-$(CONFIG_SOFTMMU) += machine.o
-
-$(obj)/op_helper.o: QEMU_CFLAGS += $(HELPER_CFLAGS)

target-m68k/helpers.h

@@ -49,6 +49,6 @@ DEF_HELPER_3(set_mac_exts, void, env, i32, i32)
 DEF_HELPER_3(set_mac_extu, void, env, i32, i32)
 
 DEF_HELPER_2(flush_flags, void, env, i32)
-DEF_HELPER_1(raise_exception, void, i32)
+DEF_HELPER_2(raise_exception, void, env, i32)
 
 #include "def-helper.h"

target-m68k/op_helper.c

@@ -17,17 +17,16 @@
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "cpu.h"
-#include "dyngen-exec.h"
 #include "helpers.h"
 
 #if defined(CONFIG_USER_ONLY)
 
-void do_interrupt(CPUM68KState *env1)
+void do_interrupt(CPUM68KState *env)
 {
-    env1->exception_index = -1;
+    env->exception_index = -1;
 }
 
-void do_interrupt_m68k_hardirq(CPUM68KState *env1)
+void do_interrupt_m68k_hardirq(CPUM68KState *env)
 {
 }
 
@@ -54,16 +53,12 @@ extern int semihosting_enabled;
 /* Try to fill the TLB and return an exception if error. If retaddr is
    NULL, it means that the function was called in C code (i.e. not
    from generated code or from helper.c) */
-/* XXX: fix it to restore all registers */
-void tlb_fill(CPUM68KState *env1, target_ulong addr, int is_write, int mmu_idx,
+void tlb_fill(CPUM68KState *env, target_ulong addr, int is_write, int mmu_idx,
               uintptr_t retaddr)
 {
     TranslationBlock *tb;
-    CPUM68KState *saved_env;
     int ret;
 
-    saved_env = env;
-    env = env1;
     ret = cpu_m68k_handle_mmu_fault(env, addr, is_write, mmu_idx);
     if (unlikely(ret)) {
         if (retaddr) {
@@ -77,24 +72,23 @@ void tlb_fill(CPUM68KState *env1, target_ulong addr, int is_write, int mmu_idx,
         }
         cpu_loop_exit(env);
     }
-    env = saved_env;
 }
 
-static void do_rte(void)
+static void do_rte(CPUM68KState *env)
 {
     uint32_t sp;
     uint32_t fmt;
 
     sp = env->aregs[7];
-    fmt = ldl_kernel(sp);
-    env->pc = ldl_kernel(sp + 4);
+    fmt = cpu_ldl_kernel(env, sp);
+    env->pc = cpu_ldl_kernel(env, sp + 4);
     sp |= (fmt >> 28) & 3;
     env->sr = fmt & 0xffff;
     m68k_switch_sp(env);
     env->aregs[7] = sp + 8;
 }
 
-static void do_interrupt_all(int is_hw)
+static void do_interrupt_all(CPUM68KState *env, int is_hw)
 {
     uint32_t sp;
     uint32_t fmt;
@@ -108,14 +102,14 @@ static void do_interrupt_all(int is_hw)
         switch (env->exception_index) {
         case EXCP_RTE:
             /* Return from an exception.  */
-            do_rte();
+            do_rte(env);
             return;
         case EXCP_HALT_INSN:
             if (semihosting_enabled
                     && (env->sr & SR_S) != 0
                     && (env->pc & 3) == 0
-                    && lduw_code(env->pc - 4) == 0x4e71
-                    && ldl_code(env->pc) == 0x4e7bf000) {
+                    && cpu_lduw_code(env, env->pc - 4) == 0x4e71
+                    && cpu_ldl_code(env, env->pc) == 0x4e7bf000) {
                 env->pc += 4;
                 do_m68k_semihosting(env, env->dregs[0]);
                 return;
@@ -151,44 +145,34 @@ static void do_interrupt_all(int is_hw)
     /* ??? This could cause MMU faults.  */
     sp &= ~3;
     sp -= 4;
-    stl_kernel(sp, retaddr);
+    cpu_stl_kernel(env, sp, retaddr);
     sp -= 4;
-    stl_kernel(sp, fmt);
+    cpu_stl_kernel(env, sp, fmt);
     env->aregs[7] = sp;
     /* Jump to vector.  */
-    env->pc = ldl_kernel(env->vbr + vector);
+    env->pc = cpu_ldl_kernel(env, env->vbr + vector);
 }
 
-void do_interrupt(CPUM68KState *env1)
+void do_interrupt(CPUM68KState *env)
 {
-    CPUM68KState *saved_env;
-
-    saved_env = env;
-    env = env1;
-    do_interrupt_all(0);
-    env = saved_env;
+    do_interrupt_all(env, 0);
 }
 
-void do_interrupt_m68k_hardirq(CPUM68KState *env1)
+void do_interrupt_m68k_hardirq(CPUM68KState *env)
 {
-    CPUM68KState *saved_env;
-
-    saved_env = env;
-    env = env1;
-    do_interrupt_all(1);
-    env = saved_env;
+    do_interrupt_all(env, 1);
 }
 #endif
 
-static void raise_exception(int tt)
+static void raise_exception(CPUM68KState *env, int tt)
 {
     env->exception_index = tt;
     cpu_loop_exit(env);
 }
 
-void HELPER(raise_exception)(uint32_t tt)
+void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt)
 {
-    raise_exception(tt);
+    raise_exception(env, tt);
 }
 
 void HELPER(divu)(CPUM68KState *env, uint32_t word)
@@ -202,8 +186,9 @@ void HELPER(divu)(CPUM68KState *env, uint32_t word)
     num = env->div1;
     den = env->div2;
     /* ??? This needs to make sure the throwing location is accurate.  */
-    if (den == 0)
-        raise_exception(EXCP_DIV0);
+    if (den == 0) {
+        raise_exception(env, EXCP_DIV0);
+    }
     quot = num / den;
     rem = num % den;
     flags = 0;
@@ -231,8 +216,9 @@ void HELPER(divs)(CPUM68KState *env, uint32_t word)
 
     num = env->div1;
     den = env->div2;
-    if (den == 0)
-        raise_exception(EXCP_DIV0);
+    if (den == 0) {
+        raise_exception(env, EXCP_DIV0);
+    }
     quot = num / den;
     rem = num % den;
     flags = 0;