x86: split off exception handlers

Move exception handlers from op_helper.c to excp_helper.c.

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

1 files changed, 132 insertions, 0 deletions

diff --git a/target-i386/excp_helper.c b/target-i386/excp_helper.c
new file mode 100644
index 0000000..72bd46d
--- /dev/null
+++ b/target-i386/excp_helper.c
@@ -0,0 +1,132 @@
+/*
+ *  x86 exception helpers
+ *
+ *  Copyright (c) 2003 Fabrice Bellard
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "cpu.h"
+#include "qemu-log.h"
+#include "helper.h"
+
+#if 0
+#define raise_exception_err(env, a, b)                                  \
+    do {                                                                \
+        qemu_log("raise_exception line=%d\n", __LINE__);                \
+        (raise_exception_err)(env, a, b);                               \
+    } while (0)
+#endif
+
+void helper_raise_interrupt(CPUX86State *env, int intno, int next_eip_addend)
+{
+    raise_interrupt(env, intno, 1, 0, next_eip_addend);
+}
+
+void helper_raise_exception(CPUX86State *env, int exception_index)
+{
+    raise_exception(env, exception_index);
+}
+
+
+/* This should come from sysemu.h - if we could include it here... */
+void qemu_system_reset_request(void);
+
+/*
+ * Check nested exceptions and change to double or triple fault if
+ * needed. It should only be called, if this is not an interrupt.
+ * Returns the new exception number.
+ */
+static int check_exception(CPUX86State *env, int intno, int *error_code)
+{
+    int first_contributory = env->old_exception == 0 ||
+                              (env->old_exception >= 10 &&
+                               env->old_exception <= 13);
+    int second_contributory = intno == 0 ||
+                               (intno >= 10 && intno <= 13);
+
+    qemu_log_mask(CPU_LOG_INT, "check_exception old: 0x%x new 0x%x\n",
+                env->old_exception, intno);
+
+#if !defined(CONFIG_USER_ONLY)
+    if (env->old_exception == EXCP08_DBLE) {
+        if (env->hflags & HF_SVMI_MASK) {
+            cpu_vmexit(env, SVM_EXIT_SHUTDOWN, 0); /* does not return */
+        }
+
+        qemu_log_mask(CPU_LOG_RESET, "Triple fault\n");
+
+        qemu_system_reset_request();
+        return EXCP_HLT;
+    }
+#endif
+
+    if ((first_contributory && second_contributory)
+        || (env->old_exception == EXCP0E_PAGE &&
+            (second_contributory || (intno == EXCP0E_PAGE)))) {
+        intno = EXCP08_DBLE;
+        *error_code = 0;
+    }
+
+    if (second_contributory || (intno == EXCP0E_PAGE) ||
+        (intno == EXCP08_DBLE)) {
+        env->old_exception = intno;
+    }
+
+    return intno;
+}
+
+/*
+ * Signal an interruption. It is executed in the main CPU loop.
+ * is_int is TRUE if coming from the int instruction. next_eip is the
+ * EIP value AFTER the interrupt instruction. It is only relevant if
+ * is_int is TRUE.
+ */
+static void QEMU_NORETURN raise_interrupt2(CPUX86State *env, int intno,
+                                           int is_int, int error_code,
+                                           int next_eip_addend)
+{
+    if (!is_int) {
+        cpu_svm_check_intercept_param(env, SVM_EXIT_EXCP_BASE + intno,
+                                      error_code);
+        intno = check_exception(env, intno, &error_code);
+    } else {
+        cpu_svm_check_intercept_param(env, SVM_EXIT_SWINT, 0);
+    }
+
+    env->exception_index = intno;
+    env->error_code = error_code;
+    env->exception_is_int = is_int;
+    env->exception_next_eip = env->eip + next_eip_addend;
+    cpu_loop_exit(env);
+}
+
+/* shortcuts to generate exceptions */
+
+void QEMU_NORETURN raise_interrupt(CPUX86State *env, int intno, int is_int,
+                                   int error_code, int next_eip_addend)
+{
+    raise_interrupt2(env, intno, is_int, error_code, next_eip_addend);
+}
+
+void raise_exception_err(CPUX86State *env, int exception_index,
+                         int error_code)
+{
+    raise_interrupt2(env, exception_index, 0, error_code, 0);
+}
+
+void raise_exception(CPUX86State *env, int exception_index)
+{
+    raise_interrupt2(env, exception_index, 0, 0, 0);
+}