[PATCH] tcg: Avoid recursion in tcg_gen_mulu2_i32

[Richard Henderson <richard.henderson@linaro.org>]

We have a test for one of TCG_TARGET_HAS_mulu2_i32 or
TCG_TARGET_HAS_muluh_i32 being defined, but the test
became non-functional when we changed to always define
all of these macros.

Replace this with a build-time test in tcg_gen_mulu2_i32.

Fixes: 25c4d9cc845 ("tcg: Always define all of the TCGOpcode enum members.")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1435
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/tcg/tcg.h | 7 -------
 tcg/tcg-op.c      | 4 +++-
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
index b949d75fdd..97429bdb89 100644
--- a/include/tcg/tcg.h
+++ b/include/tcg/tcg.h
@@ -155,13 +155,6 @@ typedef uint64_t TCGRegSet;
 #define TCG_TARGET_HAS_rem_i64          0
 #endif
 
-/* For 32-bit targets, some sort of unsigned widening multiply is required.  */
-#if TCG_TARGET_REG_BITS == 32 \
-    && !(defined(TCG_TARGET_HAS_mulu2_i32) \
-         || defined(TCG_TARGET_HAS_muluh_i32))
-# error "Missing unsigned widening multiply"
-#endif
-
 #if !defined(TCG_TARGET_HAS_v64) \
     && !defined(TCG_TARGET_HAS_v128) \
     && !defined(TCG_TARGET_HAS_v256)
diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c
index cd1cd4e736..d7e556fe0c 100644
--- a/tcg/tcg-op.c
+++ b/tcg/tcg-op.c
@@ -874,7 +874,7 @@ void tcg_gen_mulu2_i32(TCGv_i32 rl, TCGv_i32 rh, TCGv_i32 arg1, TCGv_i32 arg2)
         tcg_gen_op3_i32(INDEX_op_muluh_i32, rh, arg1, arg2);
         tcg_gen_mov_i32(rl, t);
         tcg_temp_free_i32(t);
-    } else {
+    } else if (TCG_TARGET_REG_BITS == 64) {
         TCGv_i64 t0 = tcg_temp_new_i64();
         TCGv_i64 t1 = tcg_temp_new_i64();
         tcg_gen_extu_i32_i64(t0, arg1);
@@ -883,6 +883,8 @@ void tcg_gen_mulu2_i32(TCGv_i32 rl, TCGv_i32 rh, TCGv_i32 arg1, TCGv_i32 arg2)
         tcg_gen_extr_i64_i32(rl, rh, t0);
         tcg_temp_free_i64(t0);
         tcg_temp_free_i64(t1);
+    } else {
+        qemu_build_not_reached();
     }
 }
 
-- 
2.34.1