Hi Martin,
On 6/1/26 14:43, Martin Kröning via wrote:
These functions are needed for CPUs that support runtime-configurable
endianness.
In those cases, components such as semihosting need to perform
runtime-dependent byte swaps.
Are you targetting user or system emulation?
I suppose user emulation, otherwise you'd have used the
"semihosting/uaccess.h" API.
But then I'm confused because a user process can't change
the CPU endianness...
Can you explain your use case?
Signed-off-by: Martin Kröning <[email protected]>
---
include/exec/tswap.h | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/include/exec/tswap.h b/include/exec/tswap.h
index 72219e2c43..9aaafb12f3 100644
--- a/include/exec/tswap.h
+++ b/include/exec/tswap.h
@@ -10,6 +10,7 @@
#include "qemu/bswap.h"
#include "qemu/target-info.h"
+#include "hw/core/cpu.h"
/*
* If we're in target-specific code, we can hard-code the swapping
@@ -21,6 +22,8 @@
#define target_needs_bswap() (HOST_BIG_ENDIAN != target_big_endian())
#endif /* COMPILING_PER_TARGET */
+#define cpu_needs_bswap(cpu) (HOST_BIG_ENDIAN != cpu_virtio_is_big_endian(cpu))
+
static inline uint16_t tswap16(uint16_t s)
{
if (target_needs_bswap()) {
@@ -48,6 +51,33 @@ static inline uint64_t tswap64(uint64_t s)
}
}
+static inline uint16_t cpu_tswap16(CPUState *cpu, uint16_t s)
+{
+ if (target_needs_bswap() || cpu_needs_bswap(cpu)) {
+ return bswap16(s);
+ } else {
+ return s;
+ }
+}
+
+static inline uint32_t cpu_tswap32(CPUState *cpu, uint32_t s)
+{
+ if (target_needs_bswap() || cpu_needs_bswap(cpu)) {
+ return bswap32(s);
+ } else {
+ return s;
+ }
+}
+
+static inline uint64_t cpu_tswap64(CPUState *cpu, uint64_t s)
+{
+ if (target_needs_bswap() || cpu_needs_bswap(cpu)) {
+ return bswap64(s);
+ } else {
+ return s;
+ }
+}
+
static inline void tswap16s(uint16_t *s)
{
if (target_needs_bswap()) {
