On 2025-10-20 15:14, Philippe Mathieu-Daudé wrote:
When multiple QEMU targets are variants (word size, endianness)
of the same base architecture, target_base_arch() returns this
base. For example, for the Aarch64 target it will return
SYS_EMU_TARGET_ARM as common base.
I'm not sure that reusing semantic on a subset of this enum is the best
idea, so many things can go wrong.
More widely, I don't know where we would need to access this, versus
specific functions like target_base_arm().
If a code needs to check various base archs target_base_*, or it can use
a switch with all variants.
If we really want to have this target_base concept, at least it deserves
it's own enum, separate from SYS_EMU_TARGET.
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
---
include/qemu/target-info-impl.h | 2 ++
include/qemu/target-info-qapi.h | 7 +++++++
target-info-stub.c | 1 +
target-info.c | 10 ++++++++++
4 files changed, 20 insertions(+)
diff --git a/include/qemu/target-info-impl.h b/include/qemu/target-info-impl.h
index e446585bf53..2c171f8359b 100644
--- a/include/qemu/target-info-impl.h
+++ b/include/qemu/target-info-impl.h
@@ -17,6 +17,8 @@ typedef struct TargetInfo {
const char *target_name;
/* related to TARGET_ARCH definition */
SysEmuTarget target_arch;
+ /* related to TARGET_BASE_ARCH definition (target/${base_arch}/ path) */
+ SysEmuTarget target_base_arch;
/* runtime equivalent of TARGET_LONG_BITS definition */
unsigned long_bits;
/* runtime equivalent of CPU_RESOLVING_TYPE definition */
diff --git a/include/qemu/target-info-qapi.h b/include/qemu/target-info-qapi.h
index d5ce0523238..65ed4ca8eea 100644
--- a/include/qemu/target-info-qapi.h
+++ b/include/qemu/target-info-qapi.h
@@ -19,6 +19,13 @@
*/
SysEmuTarget target_arch(void);
+/**
+ * target_base_arch:
+ *
+ * Returns: QAPI SysEmuTarget enum (i.e. SYS_EMU_TARGET_I386).
+ */
+SysEmuTarget target_base_arch(void);
+
/**
* target_endian_mode:
*
diff --git a/target-info-stub.c b/target-info-stub.c
index d96d8249c1d..d2cfca1b4c2 100644
--- a/target-info-stub.c
+++ b/target-info-stub.c
@@ -19,6 +19,7 @@ QEMU_BUILD_BUG_ON(offsetof(ArchCPU, env) != sizeof(CPUState));
static const TargetInfo target_info_stub = {
.target_name = TARGET_NAME,
.target_arch = SYS_EMU_TARGET__MAX,
+ .target_base_arch = SYS_EMU_TARGET__MAX,
And nothing can enforce base and arch match by design, which is a
problem IMHO.
.long_bits = TARGET_LONG_BITS,
.cpu_type = CPU_RESOLVING_TYPE,
.machine_typename = TYPE_MACHINE,
diff --git a/target-info.c b/target-info.c
index e567cb4c40a..332198e40a2 100644
--- a/target-info.c
+++ b/target-info.c
@@ -33,6 +33,16 @@ SysEmuTarget target_arch(void)
return arch;
}
+SysEmuTarget target_base_arch(void)
+{
+ SysEmuTarget base_arch = target_info()->target_base_arch;
+
+ if (base_arch == SYS_EMU_TARGET__MAX) {
+ base_arch = target_arch();
+ }
+ return base_arch;
More confusing, we can eventually return a non base arch if base arch
was not correctly set above.
+}
+
const char *target_cpu_type(void)
{
return target_info()->cpu_type;
