diff options
| author | Artyom Kunakovsky <artyomkunakovsky@gmail.com> | 2024-05-23 08:11:18 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-05-24 09:27:56 +0200 |
| commit | c2bf2ccb266dc9ae4a6da75b845f54535417e109 (patch) | |
| tree | c168c5f4bbf70434b09e0fc408ef721c6bc92bdb | |
| parent | 70581940cabcc51b329652becddfbc6a261b1b83 (diff) | |
configure: move -mcx16 flag out of CPU_CFLAGS
The point of CPU_CFLAGS is really just to select the appropriate multilib,
for example for library linking tests, and -mcx16 is not needed for
that purpose.
Furthermore, if -mcx16 is part of QEMU's choice of a basic x86_64
instruction set, it should be applied to cross-compiled x86_64 code too;
it is plausible that tests/tcg would want to cover cmpxchg16b as well,
for example. In the end this makes just as much sense as a per sub-build
tweak, so move the flag to meson.build and cross_cc_cflags_x86_64.
This leaves out contrib/plugins, which would fail when attempting to use
__sync_val_compare_and_swap_16 (note it does not do yet); while minor,
this *is* a disadvantage of this change. But building contrib/plugins
with a Makefile instead of meson.build is something self-inflicted just
for the sake of showing that it can be done, and if this kind of papercut
started becoming a problem we could make the directory part of the meson
build. Until then, we can live with the limitation.
Signed-off-by: Artyom Kunakovsky <artyomkunakovsky@gmail.com>
Message-ID: <20240523051118.29367-1-artyomkunakovsky@gmail.com>
[rewrite commit message, remove from configure. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rwxr-xr-x | configure | 7 | ||||
| -rw-r--r-- | meson.build | 7 |
2 files changed, 9 insertions, 5 deletions
@@ -512,10 +512,7 @@ case "$cpu" in cpu="x86_64" host_arch=x86_64 linux_arch=x86 - # ??? Only extremely old AMD cpus do not have cmpxchg16b. - # If we truly care, we should simply detect this case at - # runtime and generate the fallback to serial emulation. - CPU_CFLAGS="-m64 -mcx16" + CPU_CFLAGS="-m64" ;; esac @@ -1203,7 +1200,7 @@ fi : ${cross_cc_cflags_sparc64="-m64 -mcpu=ultrasparc"} : ${cross_cc_sparc="$cross_cc_sparc64"} : ${cross_cc_cflags_sparc="-m32 -mcpu=supersparc"} -: ${cross_cc_cflags_x86_64="-m64"} +: ${cross_cc_cflags_x86_64="-m64 -mcx16"} compute_target_variable() { eval "$2=" diff --git a/meson.build b/meson.build index a9de71d450..7fd82b5f48 100644 --- a/meson.build +++ b/meson.build @@ -336,6 +336,13 @@ if host_arch == 'i386' and not cc.links(''' qemu_common_flags = ['-march=i486'] + qemu_common_flags endif +# ??? Only extremely old AMD cpus do not have cmpxchg16b. +# If we truly care, we should simply detect this case at +# runtime and generate the fallback to serial emulation. +if host_arch == 'x86_64' + qemu_common_flags = ['-mcx16'] + qemu_common_flags +endif + if get_option('prefer_static') qemu_ldflags += get_option('b_pie') ? '-static-pie' : '-static' endif |