memory: Single byte swap along the I/O path

Now that MemOp has been pushed down into the memory API, and
callers are encoding endianness, we can collapse byte swaps
along the I/O path into the accelerator and target independent
adjust_endianness.

Collapsing byte swaps along the I/O path enables additional endian
inversion logic, e.g. SPARC64 Invert Endian TTE bit, with redundant
byte swaps cancelling out.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Tony Nguyen <tony.nguyen@bt.com>
Message-Id: <911ff31af11922a9afba9b7ce128af8b8b80f316.1566466906.git.tony.nguyen@bt.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 0 insertions, 63 deletions

diff --git a/memory_ldst.inc.c b/memory_ldst.inc.c
index 809a7e8389..c54aee4a95 100644
--- a/memory_ldst.inc.c
+++ b/memory_ldst.inc.c
@@ -38,18 +38,8 @@ static inline uint32_t glue(address_space_ldl_internal, SUFFIX)(ARG1_DECL,
         release_lock |= prepare_mmio_access(mr);
 
         /* I/O case */
-        /* TODO: Merge bswap32 into memory_region_dispatch_read.  */
         r = memory_region_dispatch_read(mr, addr1, &val,
                                         MO_32 | devend_memop(endian), attrs);
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap32(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap32(val);
-        }
-#endif
     } else {
         /* RAM case */
         ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
@@ -116,18 +106,8 @@ static inline uint64_t glue(address_space_ldq_internal, SUFFIX)(ARG1_DECL,
         release_lock |= prepare_mmio_access(mr);
 
         /* I/O case */
-        /* TODO: Merge bswap64 into memory_region_dispatch_read.  */
         r = memory_region_dispatch_read(mr, addr1, &val,
                                         MO_64 | devend_memop(endian), attrs);
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap64(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap64(val);
-        }
-#endif
     } else {
         /* RAM case */
         ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
@@ -228,18 +208,8 @@ static inline uint32_t glue(address_space_lduw_internal, SUFFIX)(ARG1_DECL,
         release_lock |= prepare_mmio_access(mr);
 
         /* I/O case */
-        /* TODO: Merge bswap16 into memory_region_dispatch_read.  */
         r = memory_region_dispatch_read(mr, addr1, &val,
                                         MO_16 | devend_memop(endian), attrs);
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap16(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap16(val);
-        }
-#endif
     } else {
         /* RAM case */
         ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
@@ -342,17 +312,6 @@ static inline void glue(address_space_stl_internal, SUFFIX)(ARG1_DECL,
     mr = TRANSLATE(addr, &addr1, &l, true, attrs);
     if (l < 4 || !memory_access_is_direct(mr, true)) {
         release_lock |= prepare_mmio_access(mr);
-
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap32(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap32(val);
-        }
-#endif
-        /* TODO: Merge bswap32 into memory_region_dispatch_write.  */
         r = memory_region_dispatch_write(mr, addr1, val,
                                          MO_32 | devend_memop(endian), attrs);
     } else {
@@ -449,17 +408,6 @@ static inline void glue(address_space_stw_internal, SUFFIX)(ARG1_DECL,
     mr = TRANSLATE(addr, &addr1, &l, true, attrs);
     if (l < 2 || !memory_access_is_direct(mr, true)) {
         release_lock |= prepare_mmio_access(mr);
-
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap16(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap16(val);
-        }
-#endif
-        /* TODO: Merge bswap16 into memory_region_dispatch_write.  */
         r = memory_region_dispatch_write(mr, addr1, val,
                                          MO_16 | devend_memop(endian), attrs);
     } else {
@@ -524,17 +472,6 @@ static void glue(address_space_stq_internal, SUFFIX)(ARG1_DECL,
     mr = TRANSLATE(addr, &addr1, &l, true, attrs);
     if (l < 8 || !memory_access_is_direct(mr, true)) {
         release_lock |= prepare_mmio_access(mr);
-
-#if defined(TARGET_WORDS_BIGENDIAN)
-        if (endian == DEVICE_LITTLE_ENDIAN) {
-            val = bswap64(val);
-        }
-#else
-        if (endian == DEVICE_BIG_ENDIAN) {
-            val = bswap64(val);
-        }
-#endif
-        /* TODO: Merge bswap64 into memory_region_dispatch_write.  */
         r = memory_region_dispatch_write(mr, addr1, val,
                                          MO_64 | devend_memop(endian), attrs);
     } else {