[Qemu-devel] [PATCH 4/7] target-i386: Dump illegal opcodes with -d unimp

[Richard Henderson <rth@twiddle.net>]

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 target-i386/translate.c | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/target-i386/translate.c b/target-i386/translate.c
index b73c237..aa423cb 100644
--- a/target-i386/translate.c
+++ b/target-i386/translate.c
@@ -99,6 +99,7 @@ typedef struct DisasContext {
     int prefix;
     TCGMemOp aflag;
     TCGMemOp dflag;
+    target_ulong pc_start;
     target_ulong pc; /* pc = eip + cs_base */
     int is_jmp; /* 1 = means jump (stop translation), 2 means CPU
                    static state change (stop translation) */
@@ -2368,6 +2369,21 @@ static void gen_exception(DisasContext *s, int trapno, target_ulong cur_eip)
     s->is_jmp = DISAS_TB_JUMP;
 }
 
+static void gen_illop(CPUX86State *env, DisasContext *s)
+{
+    target_ulong pc = s->pc_start;
+    gen_exception(s, EXCP06_ILLOP, pc - s->cs_base);
+
+    if (qemu_loglevel_mask(LOG_UNIMP)) {
+        target_ulong end = s->pc;
+        qemu_log("ILLOPC: " TARGET_FMT_lx ":", pc);
+        for (; pc < end; ++pc) {
+            qemu_log(" %02x", cpu_ldub_code(env, pc));
+        }
+        qemu_log("\n");
+    }
+}
+
 /* an interrupt is different from an exception because of the
    privilege checks */
 static void gen_interrupt(DisasContext *s, int intno,
@@ -2893,7 +2909,7 @@ static void gen_sse(CPUX86State *env, DisasContext *s, int b,
     }
     if (s->flags & HF_EM_MASK) {
     illegal_op:
-        gen_exception(s, EXCP06_ILLOP, pc_start - s->cs_base);
+        gen_illop(env, s);
         return;
     }
     if (is_xmm && !(s->flags & HF_OSFXSR_MASK))
@@ -4293,7 +4309,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
     target_ulong next_eip, tval;
     int rex_w, rex_r;
 
-    s->pc = pc_start;
+    s->pc_start = s->pc = pc_start;
     prefixes = 0;
     s->override = -1;
     rex_w = -1;
@@ -8031,7 +8047,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
     if (s->prefix & PREFIX_LOCK)
         gen_helper_unlock();
     /* XXX: ensure that no lock was generated */
-    gen_exception(s, EXCP06_ILLOP, pc_start - s->cs_base);
+    gen_illop(env, s);
     return s->pc;
 }
 
-- 
2.5.0