Replace config-time define HOST_WORDS_BIGENDIAN

Replace a config-time define with a compile time condition
define (compatible with clang and gcc) that must be declared prior to
its usage. This avoids having a global configure time define, but also
prevents from bad usage, if the config header wasn't included before.

This can help to make some code independent from qemu too.

gcc supports __BYTE_ORDER__ from about 4.6 and clang from 3.2.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[ For the s390x parts I'm involved in ]
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

accel/kvm/kvm-all.c

@@ -1202,8 +1202,8 @@ void kvm_hwpoison_page_add(ram_addr_t ram_addr)
 
 static uint32_t adjust_ioeventfd_endianness(uint32_t val, uint32_t size)
 {
-#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
-    /* The kernel expects ioeventfd values in HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN != defined(TARGET_WORDS_BIGENDIAN)
+    /* The kernel expects ioeventfd values in HOST_BIG_ENDIAN
      * endianness, but the memory core hands them in target endianness.
      * For example, PPC is always treated as big-endian even if running
      * on KVM and on PPC64LE.  Correct here.

accel/tcg/atomic_template.h

@@ -63,7 +63,7 @@
    the ATOMIC_NAME macro, and redefined below.  */
 #if DATA_SIZE == 1
 # define END
-#elif defined(HOST_WORDS_BIGENDIAN)
+#elif HOST_BIG_ENDIAN
 # define END  _be
 #else
 # define END  _le
@@ -196,7 +196,7 @@ GEN_ATOMIC_HELPER_FN(umax_fetch, MAX,  DATA_TYPE, new)
 
 /* Define reverse-host-endian atomic operations.  Note that END is used
    within the ATOMIC_NAME macro.  */
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 # define END  _le
 #else
 # define END  _be

audio/audio.h

@@ -32,7 +32,7 @@
 
 typedef void (*audio_callback_fn) (void *opaque, int avail);
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define AUDIO_HOST_ENDIANNESS 1
 #else
 #define AUDIO_HOST_ENDIANNESS 0

audio/dbusaudio.c

@@ -122,7 +122,7 @@ static size_t dbus_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)
     return size;
 }
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define AUDIO_HOST_BE TRUE
 #else
 #define AUDIO_HOST_BE FALSE

disas.c

@@ -144,7 +144,7 @@ static void initialize_debug_host(CPUDebug *s)
 
     s->info.read_memory_func = host_read_memory;
     s->info.print_address_func = host_print_address;
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     s->info.endian = BFD_ENDIAN_BIG;
 #else
     s->info.endian = BFD_ENDIAN_LITTLE;

hw/core/loader.c

@@ -474,7 +474,7 @@ ssize_t load_elf_ram_sym(const char *filename,
         ret = ELF_LOAD_NOT_ELF;
         goto fail;
     }
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     data_order = ELFDATA2MSB;
 #else
     data_order = ELFDATA2LSB;
@@ -511,7 +511,7 @@ ssize_t load_elf_ram_sym(const char *filename,
 
 static void bswap_uboot_header(uboot_image_header_t *hdr)
 {
-#ifndef HOST_WORDS_BIGENDIAN
+#if !HOST_BIG_ENDIAN
     bswap32s(&hdr->ih_magic);
     bswap32s(&hdr->ih_hcrc);
     bswap32s(&hdr->ih_time);

hw/display/artist.c

@@ -26,7 +26,7 @@
 #define TYPE_ARTIST "artist"
 OBJECT_DECLARE_SIMPLE_TYPE(ARTISTState, ARTIST)
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define ROP8OFF(_i) (3 - (_i))
 #else
 #define ROP8OFF
@@ -712,7 +712,7 @@ static void combine_write_reg(hwaddr addr, uint64_t val, int size, void *out)
      * FIXME: is there a qemu helper for this?
      */
 
-#ifndef HOST_WORDS_BIGENDIAN
+#if !HOST_BIG_ENDIAN
     addr ^= 3;
 #endif
 
@@ -1087,7 +1087,7 @@ static uint64_t combine_read_reg(hwaddr addr, int size, void *in)
      * FIXME: is there a qemu helper for this?
      */
 
-#ifndef HOST_WORDS_BIGENDIAN
+#if !HOST_BIG_ENDIAN
     addr ^= 3;
 #endif
 

hw/display/pl110_template.h

@@ -15,18 +15,18 @@
 
 #if ORDER == 0
 #define NAME glue(lblp_, BORDER)
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define SWAP_WORDS 1
 #endif
 #elif ORDER == 1
 #define NAME glue(bbbp_, BORDER)
-#ifndef HOST_WORDS_BIGENDIAN
+#if !HOST_BIG_ENDIAN
 #define SWAP_WORDS 1
 #endif
 #else
 #define SWAP_PIXELS 1
 #define NAME glue(lbbp_, BORDER)
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define SWAP_WORDS 1
 #endif
 #endif

hw/display/pxa2xx_lcd.c

@@ -199,7 +199,7 @@ typedef struct QEMU_PACKED {
         SKIP_PIXEL(to);          \
     } while (0)
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 # define SWAP_WORDS 1
 #endif
 

hw/display/vga.c

@@ -94,19 +94,19 @@ const uint8_t gr_mask[16] = {
                 (((uint32_t)(__x) & (uint32_t)0x00ff0000UL) >>  8) | \
                 (((uint32_t)(__x) & (uint32_t)0xff000000UL) >> 24) ))
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define PAT(x) cbswap_32(x)
 #else
 #define PAT(x) (x)
 #endif
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define BIG 1
 #else
 #define BIG 0
 #endif
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define GET_PLANE(data, p) (((data) >> (24 - (p) * 8)) & 0xff)
 #else
 #define GET_PLANE(data, p) (((data) >> ((p) * 8)) & 0xff)
@@ -133,7 +133,7 @@ static const uint32_t mask16[16] = {
 
 #undef PAT
 
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define PAT(x) (x)
 #else
 #define PAT(x) cbswap_32(x)
@@ -1296,7 +1296,7 @@ static void vga_draw_text(VGACommonState *s, int full_update)
                 if (cx > cx_max)
                     cx_max = cx;
                 *ch_attr_ptr = ch_attr;
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
                 ch = ch_attr >> 8;
                 cattr = ch_attr & 0xff;
 #else
@@ -1477,7 +1477,7 @@ static void vga_draw_graphic(VGACommonState *s, int full_update)
     vga_draw_line_func *vga_draw_line = NULL;
     bool share_surface, force_shadow = false;
     pixman_format_code_t format;
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     bool byteswap = !s->big_endian_fb;
 #else
     bool byteswap = s->big_endian_fb;

hw/display/virtio-gpu-gl.c

@@ -108,7 +108,7 @@ static void virtio_gpu_gl_device_realize(DeviceState *qdev, Error **errp)
 {
     VirtIOGPU *g = VIRTIO_GPU(qdev);
 
-#if defined(HOST_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN
     error_setg(errp, "virgl is not supported on bigendian platforms");
     return;
 #endif

hw/net/can/ctucan_core.h

@@ -31,7 +31,7 @@
 #include "exec/hwaddr.h"
 #include "net/can_emu.h"
 
-#ifndef HOST_WORDS_BIGENDIAN
+#if !HOST_BIG_ENDIAN
 #define __LITTLE_ENDIAN_BITFIELD 1
 #endif
 

hw/net/vmxnet3.h

@@ -35,7 +35,7 @@
 #define __le32  uint32_t
 #define __le64  uint64_t
 
-#if defined(HOST_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN
 #define __BIG_ENDIAN_BITFIELD
 #else
 #endif
@@ -800,7 +800,7 @@ struct Vmxnet3_DriverShared {
 #undef __le16
 #undef __le32
 #undef __le64
-#if defined(HOST_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN
 #undef __BIG_ENDIAN_BITFIELD
 #endif
 

hw/s390x/event-facility.c

@@ -28,7 +28,7 @@ typedef struct SCLPEventsBus {
 } SCLPEventsBus;
 
 /* we need to save 32 bit chunks for compatibility */
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
 #define RECV_MASK_LOWER 1
 #define RECV_MASK_UPPER 0
 #else /* little endian host */

hw/virtio/vhost.c

@@ -989,7 +989,7 @@ static inline bool vhost_needs_vring_endian(VirtIODevice *vdev)
     if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
         return false;
     }
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE;
 #else
     return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;

include/exec/cpu-all.h

@@ -34,13 +34,14 @@
 
 /* some important defines:
  *
- * HOST_WORDS_BIGENDIAN : if defined, the host cpu is big endian and
+ * HOST_BIG_ENDIAN : whether the host cpu is big endian and
  * otherwise little endian.
  *
- * TARGET_WORDS_BIGENDIAN : same for target cpu
+ * TARGET_WORDS_BIGENDIAN : if defined, the host cpu is big endian and otherwise
+ * little endian.
  */
 
-#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN != defined(TARGET_WORDS_BIGENDIAN)
 #define BSWAP_NEEDED
 #endif
 

include/exec/cpu-common.h

@@ -46,7 +46,7 @@ enum device_endian {
     DEVICE_LITTLE_ENDIAN,
 };
 
-#if defined(HOST_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN
 #define DEVICE_HOST_ENDIAN DEVICE_BIG_ENDIAN
 #else
 #define DEVICE_HOST_ENDIAN DEVICE_LITTLE_ENDIAN

include/exec/memop.h

@@ -28,7 +28,7 @@ typedef enum MemOp {
     MO_SIGN  = 0x08,   /* Sign-extended, otherwise zero-extended.  */
 
     MO_BSWAP = 0x10,   /* Host reverse endian.  */
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     MO_LE    = MO_BSWAP,
     MO_BE    = 0,
 #else

include/exec/memory.h

@@ -2931,7 +2931,7 @@ static inline MemOp devend_memop(enum device_endian end)
     QEMU_BUILD_BUG_ON(DEVICE_HOST_ENDIAN != DEVICE_LITTLE_ENDIAN &&
                       DEVICE_HOST_ENDIAN != DEVICE_BIG_ENDIAN);
 
-#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
+#if HOST_BIG_ENDIAN != defined(TARGET_WORDS_BIGENDIAN)
     /* Swap if non-host endianness or native (target) endianness */
     return (end == DEVICE_HOST_ENDIAN) ? 0 : MO_BSWAP;
 #else

include/fpu/softfloat-types.h

@@ -103,7 +103,7 @@ typedef struct {
 #define make_floatx80(exp, mant) ((floatx80) { mant, exp })
 #define make_floatx80_init(exp, mant) { .low = mant, .high = exp }
 typedef struct {
-#ifdef HOST_WORDS_BIGENDIAN
+#if HOST_BIG_ENDIAN
     uint64_t high, low;
 #else
     uint64_t low, high;