The current "#ifdef TARGET_X86_64" statement affects
the compiler's determination of fall through.
When using -Wimplicit-fallthrough in our CFLAGS on GCC9, the compiler showed
warning:
target/i386/translate.c: In function ‘gen_shiftd_rm_T1’:
target/i386/translate.c:1773:12: warning: this statement may fall through
[-Wimplicit-fallthrough=]
if (is_right) {
^
target/i386/translate.c:1782:5: note: here
case MO_32:
^~~~
Reported-by: Euler Robot <euler.ro...@huawei.com>
Signed-off-by: Chen Qun <kuhn.chen...@huawei.com>
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
Reviewed-by: Thomas Huth <th...@redhat.com>
---
v1->v2: Add comments to explain the two case of fall through,
depending on whether TARGET_X86_64 is defined.
Cc: Thomas Huth <th...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: Richard Henderson <richard.hender...@linaro.org>
Cc: Eduardo Habkost <ehabk...@redhat.com>
---
target/i386/translate.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/target/i386/translate.c b/target/i386/translate.c
index caea6f5fb1..77cb66208e 100644
--- a/target/i386/translate.c
+++ b/target/i386/translate.c
@@ -1777,9 +1777,12 @@ static void gen_shiftd_rm_T1(DisasContext *s, MemOp ot,
int op1,
} else {
tcg_gen_deposit_tl(s->T1, s->T0, s->T1, 16, 16);
}
- /* FALLTHRU */
-#ifdef TARGET_X86_64
+ /*
+ * If TARGET_X86_64 defined then fall through into MO_32 case,
+ * otherwise fall through default case.
+ */
case MO_32:
+#ifdef TARGET_X86_64
/* Concatenate the two 32-bit values and use a 64-bit shift. */
tcg_gen_subi_tl(s->tmp0, count, 1);
if (is_right) {
--
2.27.0
