[PATCH v3 16/37] target/ppc: Fix TRANS* macro variadic arguments handling

[Chinmay Rath <rathc@linux.ibm.com>]

From: Ojaswin Mujoo <ojaswin@linux.ibm.com>

Use ##__VA_ARGS__ in TRANS* macros to allow variadic arguments to be
optional instead of mandatory. "##" removes the preceding comma when
__VA_ARGS__ is empty, enabling macros to work with functions that don't
need extra parameters.

This avoid compilation errors when using a pattern like below:

  static bool do_wait(DisasContext *ctx, arg_X_wait *a)
  {...}

  TRANS_FLAGS(WAIT, WAIT_ISA_2_X, do_wait)

Compilation Error:
../target/ppc/translate.c:5526:40: error: expected expression before ‘)’ token
 5526 |         return FUNC(ctx, a, __VA_ARGS__);                      \
      |                                        ^
../target/ppc/translate/storage-ctrl-impl.c.inc:368:1: note: in expansion of macro ‘TRANS_FLAGS’
  368 | TRANS_FLAGS(WAIT, WAIT_ISA_2_X, do_wait)

Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Chinmay Rath <rathc@linux.ibm.com>
---
 target/ppc/translate.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index f5b1446d7a..322870dc0d 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -4749,29 +4749,29 @@ static int64_t dw_compose_ea(DisasContext *ctx, int x)
  */
 #define TRANS(NAME, FUNC, ...) \
     static bool trans_##NAME(DisasContext *ctx, arg_##NAME *a) \
-    { return FUNC(ctx, a, __VA_ARGS__); }
+    { return FUNC(ctx, a, ##__VA_ARGS__); }
 #define TRANS_FLAGS(FLAGS, NAME, FUNC, ...) \
     static bool trans_##NAME(DisasContext *ctx, arg_##NAME *a) \
     {                                                          \
         REQUIRE_INSNS_FLAGS(ctx, FLAGS);                       \
-        return FUNC(ctx, a, __VA_ARGS__);                      \
+        return FUNC(ctx, a, ##__VA_ARGS__);                    \
     }
 #define TRANS_FLAGS2(FLAGS2, NAME, FUNC, ...) \
     static bool trans_##NAME(DisasContext *ctx, arg_##NAME *a) \
     {                                                          \
         REQUIRE_INSNS_FLAGS2(ctx, FLAGS2);                     \
-        return FUNC(ctx, a, __VA_ARGS__);                      \
+        return FUNC(ctx, a, ##__VA_ARGS__);                    \
     }
 
 #define TRANS64(NAME, FUNC, ...) \
     static bool trans_##NAME(DisasContext *ctx, arg_##NAME *a) \
-    { REQUIRE_64BIT(ctx); return FUNC(ctx, a, __VA_ARGS__); }
+    { REQUIRE_64BIT(ctx); return FUNC(ctx, a, ##__VA_ARGS__); }
 #define TRANS64_FLAGS2(FLAGS2, NAME, FUNC, ...) \
     static bool trans_##NAME(DisasContext *ctx, arg_##NAME *a) \
     {                                                          \
         REQUIRE_64BIT(ctx);                                    \
         REQUIRE_INSNS_FLAGS2(ctx, FLAGS2);                     \
-        return FUNC(ctx, a, __VA_ARGS__);                      \
+        return FUNC(ctx, a, ##__VA_ARGS__);                    \
     }
 
 /* TODO: More TRANS* helpers for extra insn_flags checks. */
-- 
2.55.0