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https://github.com/yuzu-emu/unicorn.git
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3cf7b6dd3b
By sticking the next pointer first, we don't need a union with 64-bit padding for smaller types. On 32-bit platforms, this can reduce the size of uint8List from 16 bytes (or 12, depending on whether 64-bit ints can tolerate 4-byte alignment) down to 8. It has no effect on 64-bit platforms (where alignment still dictates a 16-byte struct); but fewer anonymous unions is still a win in my book. It requires visit_next_list() to gain a size parameter, to know what size element to allocate; comparable to the size parameter of visit_start_struct(). I debated about going one step further, to allow for fewer casts, by doing: typedef GenericList GenericList; struct GenericList { GenericList *next; }; struct FooList { GenericList base; Foo *value; }; so that you convert to 'GenericList *' by '&foolist->base', and back by 'container_of(generic, GenericList, base)' (as opposed to the existing '(GenericList *)foolist' and '(FooList *)generic'). But doing that would require hoisting the declaration of GenericList prior to inclusion of qapi-types.h, rather than its current spot in visitor.h; it also makes iteration a bit more verbose through 'foolist->base.next' instead of 'foolist->next'. Note that for lists of objects, the 'value' payload is still hidden behind a boxed pointer. Someday, it would be nice to do: struct FooList { FooList *next; Foo value; }; for one less level of malloc for each list element. This patch is a step in that direction (now that 'next' is no longer at a fixed non-zero offset within the struct, we can store more than just a pointer's-worth of data as the value payload), but the actual conversion would be a task for another series, as it will touch a lot of code. Backports commit e65d89bf1a4484e0db0f3dc820a8b209f2fb1e8b from qemu |
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.. | ||
crypto | ||
default-configs | ||
docs | ||
fpu | ||
hw | ||
include | ||
qapi | ||
qobject | ||
qom | ||
scripts | ||
target-arm | ||
target-i386 | ||
target-m68k | ||
target-mips | ||
target-sparc | ||
tcg | ||
util | ||
aarch64.h | ||
aarch64eb.h | ||
accel.c | ||
arm.h | ||
armeb.h | ||
CODING_STYLE | ||
configure | ||
COPYING | ||
COPYING.LIB | ||
cpu-exec-common.c | ||
cpu-exec.c | ||
cpus.c | ||
cputlb.c | ||
exec.c | ||
gen_all_header.sh | ||
glib_compat.c | ||
HACKING | ||
header_gen.py | ||
ioport.c | ||
LICENSE | ||
m68k.h | ||
Makefile | ||
Makefile.objs | ||
Makefile.target | ||
memory.c | ||
memory_mapping.c | ||
mips.h | ||
mips64.h | ||
mips64el.h | ||
mipsel.h | ||
powerpc.h | ||
qapi-schema.json | ||
qemu-log.c | ||
qemu-timer.c | ||
rules.mak | ||
softmmu_template.h | ||
sparc.h | ||
sparc64.h | ||
tcg-runtime.c | ||
translate-all.c | ||
translate-all.h | ||
translate-common.c | ||
unicorn_common.h | ||
VERSION | ||
vl.c | ||
vl.h | ||
x86_64.h |