[PATCH 5/5] Revert "meson: assume x86-64-v2 baseline ISA"

Alexander Monakov posted 5 patches 4 months, 1 week ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, "Daniel P. Berrangé" <berrange@redhat.com>, Thomas Huth <thuth@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>
[PATCH 5/5] Revert "meson: assume x86-64-v2 baseline ISA"
Posted by Alexander Monakov 4 months, 1 week ago
This reverts commit 294ac64e459aca023f43441651d860980c9784f1.

Reinstate the ability to use Qemu on x86 hosts that do not meet
x86_64-v2 ISA baseline.

Signed-off-by: Alexander Monakov <amonakov@ispras.ru>
---
 meson.build | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/meson.build b/meson.build
index ec59effc..49962cce 100644
--- a/meson.build
+++ b/meson.build
@@ -336,13 +336,9 @@ if host_arch == 'i386' and not cc.links('''
   qemu_common_flags = ['-march=i486'] + qemu_common_flags
 endif
 
-# Assume x86-64-v2 (minus CMPXCHG16B for 32-bit code)
-if host_arch == 'i386'
-  qemu_common_flags = ['-mfpmath=sse'] + qemu_common_flags
-endif
-if host_arch in ['i386', 'x86_64']
-  qemu_common_flags = ['-mpopcnt', '-msse4.2'] + 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
-- 
2.32.0