symbian-qemu-0.9.1-12/qemu-symbian-svp/target-m68k/op_helper.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/qemu-symbian-svp/target-m68k/op_helper.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,226 @@
+/*
+ *  M68K helper routines
+ *
+ *  Copyright (c) 2007 CodeSourcery
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "exec.h"
+#include "helpers.h"
+
+#if defined(CONFIG_USER_ONLY)
+
+void do_interrupt(int is_hw)
+{
+    env->exception_index = -1;
+}
+
+#else
+
+extern int semihosting_enabled;
+
+#define MMUSUFFIX _mmu
+
+#define SHIFT 0
+#include "softmmu_template.h"
+
+#define SHIFT 1
+#include "softmmu_template.h"
+
+#define SHIFT 2
+#include "softmmu_template.h"
+
+#define SHIFT 3
+#include "softmmu_template.h"
+
+/* 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 (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
+{
+    TranslationBlock *tb;
+    CPUState *saved_env;
+    unsigned long pc;
+    int ret;
+
+    /* XXX: hack to restore env in all cases, even if not called from
+       generated code */
+    saved_env = env;
+    env = cpu_single_env;
+    ret = cpu_m68k_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
+    if (unlikely(ret)) {
+        if (retaddr) {
+            /* now we have a real cpu fault */
+            pc = (unsigned long)retaddr;
+            tb = tb_find_pc(pc);
+            if (tb) {
+                /* the PC is inside the translated code. It means that we have
+                   a virtual CPU fault */
+                cpu_restore_state(tb, env, pc, NULL);
+            }
+        }
+        cpu_loop_exit();
+    }
+    env = saved_env;
+}
+
+static void do_rte(void)
+{
+    uint32_t sp;
+    uint32_t fmt;
+
+    sp = env->aregs[7];
+    fmt = ldl_kernel(sp);
+    env->pc = ldl_kernel(sp + 4);
+    sp |= (fmt >> 28) & 3;
+    env->sr = fmt & 0xffff;
+    m68k_switch_sp(env);
+    env->aregs[7] = sp + 8;
+}
+
+void do_interrupt(int is_hw)
+{
+    uint32_t sp;
+    uint32_t fmt;
+    uint32_t retaddr;
+    uint32_t vector;
+
+    fmt = 0;
+    retaddr = env->pc;
+
+    if (!is_hw) {
+        switch (env->exception_index) {
+        case EXCP_RTE:
+            /* Return from an exception.  */
+            do_rte();
+            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) {
+                env->pc += 4;
+                do_m68k_semihosting(env, env->dregs[0]);
+                return;
+            }
+            env->halted = 1;
+            env->exception_index = EXCP_HLT;
+            cpu_loop_exit();
+            return;
+        }
+        if (env->exception_index >= EXCP_TRAP0
+            && env->exception_index <= EXCP_TRAP15) {
+            /* Move the PC after the trap instruction.  */
+            retaddr += 2;
+        }
+    }
+
+    vector = env->exception_index << 2;
+
+    sp = env->aregs[7];
+
+    fmt |= 0x40000000;
+    fmt |= (sp & 3) << 28;
+    fmt |= vector << 16;
+    fmt |= env->sr;
+
+    env->sr |= SR_S;
+    if (is_hw) {
+        env->sr = (env->sr & ~SR_I) | (env->pending_level << SR_I_SHIFT);
+        env->sr &= ~SR_M;
+    }
+    m68k_switch_sp(env);
+
+    /* ??? This could cause MMU faults.  */
+    sp &= ~3;
+    sp -= 4;
+    stl_kernel(sp, retaddr);
+    sp -= 4;
+    stl_kernel(sp, fmt);
+    env->aregs[7] = sp;
+    /* Jump to vector.  */
+    env->pc = ldl_kernel(env->vbr + vector);
+}
+
+#endif
+
+static void raise_exception(int tt)
+{
+    env->exception_index = tt;
+    cpu_loop_exit();
+}
+
+void HELPER(raise_exception)(uint32_t tt)
+{
+    raise_exception(tt);
+}
+
+void HELPER(divu)(CPUState *env, uint32_t word)
+{
+    uint32_t num;
+    uint32_t den;
+    uint32_t quot;
+    uint32_t rem;
+    uint32_t flags;
+
+    num = env->div1;
+    den = env->div2;
+    /* ??? This needs to make sure the throwing location is accurate.  */
+    if (den == 0)
+        raise_exception(EXCP_DIV0);
+    quot = num / den;
+    rem = num % den;
+    flags = 0;
+    /* Avoid using a PARAM1 of zero.  This breaks dyngen because it uses
+       the address of a symbol, and gcc knows symbols can't have address
+       zero.  */
+    if (word && quot > 0xffff)
+        flags |= CCF_V;
+    if (quot == 0)
+        flags |= CCF_Z;
+    else if ((int32_t)quot < 0)
+        flags |= CCF_N;
+    env->div1 = quot;
+    env->div2 = rem;
+    env->cc_dest = flags;
+}
+
+void HELPER(divs)(CPUState *env, uint32_t word)
+{
+    int32_t num;
+    int32_t den;
+    int32_t quot;
+    int32_t rem;
+    int32_t flags;
+
+    num = env->div1;
+    den = env->div2;
+    if (den == 0)
+        raise_exception(EXCP_DIV0);
+    quot = num / den;
+    rem = num % den;
+    flags = 0;
+    if (word && quot != (int16_t)quot)
+        flags |= CCF_V;
+    if (quot == 0)
+        flags |= CCF_Z;
+    else if (quot < 0)
+        flags |= CCF_N;
+    env->div1 = quot;
+    env->div2 = rem;
+    env->cc_dest = flags;
+}