target/arm: Move endian adjustment macros to vec_internal.h

We have two copies of these, one set of which is not complete.
Move them to a common header.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210525010358.152808-82-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/target/arm/vec_internal.h b/target/arm/vec_internal.h
index ff694d870a..dba481e001 100644
--- a/target/arm/vec_internal.h
+++ b/target/arm/vec_internal.h
@@ -20,6 +20,30 @@
 #ifndef TARGET_ARM_VEC_INTERNALS_H
 #define TARGET_ARM_VEC_INTERNALS_H
 
+/*
+ * Note that vector data is stored in host-endian 64-bit chunks,
+ * so addressing units smaller than that needs a host-endian fixup.
+ *
+ * The H<N> macros are used when indexing an array of elements of size N.
+ *
+ * The H1_<N> macros are used when performing byte arithmetic and then
+ * casting the final pointer to a type of size N.
+ */
+#ifdef HOST_WORDS_BIGENDIAN
+#define H1(x)   ((x) ^ 7)
+#define H1_2(x) ((x) ^ 6)
+#define H1_4(x) ((x) ^ 4)
+#define H2(x)   ((x) ^ 3)
+#define H4(x)   ((x) ^ 1)
+#else
+#define H1(x)   (x)
+#define H1_2(x) (x)
+#define H1_4(x) (x)
+#define H2(x)   (x)
+#define H4(x)   (x)
+#endif
+
+
 static inline void clear_tail(void *vd, uintptr_t opr_sz, uintptr_t max_sz)
 {
     uint64_t *d = vd + opr_sz;