meson: allow configuring the x86-64 baseline
Add a Meson option to configure which x86-64 instruction
set to use. QEMU will now default to x86-64-v1 + cmpxchg16b for
64-bit builds (that corresponds to a Pentium 4 for 32-bit builds).
The baseline can be tuned down to Pentium Pro for 32-bit builds (with
-Dx86_version=0), or up as desired.
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/meson.build b/meson.build
index 97e00d6..6e694ec 100644
--- a/meson.build
+++ b/meson.build
@@ -336,15 +336,40 @@
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
+# Pick x86-64 baseline version
if host_arch in ['i386', 'x86_64']
- qemu_common_flags = ['-mpopcnt', '-msse4.2'] + qemu_common_flags
-endif
-if host_arch == 'x86_64'
- qemu_common_flags = ['-mcx16'] + qemu_common_flags
+ if get_option('x86_version') == '0' and host_arch == 'x86_64'
+ error('x86_64-v1 required for x86-64 hosts')
+ endif
+
+ # add flags for individual instruction set extensions
+ if get_option('x86_version') >= '1'
+ if host_arch == 'i386'
+ qemu_common_flags = ['-mfpmath=sse'] + qemu_common_flags
+ else
+ # present on basically all processors but technically not part of
+ # x86-64-v1, so only include -mneeded for x86-64 version 2 and above
+ qemu_common_flags = ['-mcx16'] + qemu_common_flags
+ endif
+ endif
+ if get_option('x86_version') >= '2'
+ qemu_common_flags = ['-mpopcnt'] + qemu_common_flags
+ qemu_common_flags = cc.get_supported_arguments('-mneeded') + qemu_common_flags
+ endif
+ if get_option('x86_version') >= '3'
+ qemu_common_flags = ['-mmovbe', '-mabm', '-mbmi1', '-mbmi2', '-mfma', '-mf16c'] + qemu_common_flags
+ endif
+
+ # add required vector instruction set (each level implies those below)
+ if get_option('x86_version') == '1'
+ qemu_common_flags = ['-msse2'] + qemu_common_flags
+ elif get_option('x86_version') == '2'
+ qemu_common_flags = ['-msse4.2'] + qemu_common_flags
+ elif get_option('x86_version') == '3'
+ qemu_common_flags = ['-mavx2'] + qemu_common_flags
+ elif get_option('x86_version') == '4'
+ qemu_common_flags = ['-mavx512f', '-mavx512bw', '-mavx512cd', '-mavx512dq', '-mavx512vl'] + qemu_common_flags
+ endif
endif
if get_option('prefer_static')
diff --git a/meson_options.txt b/meson_options.txt
index 7a79dd8..6065ed2 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -370,3 +370,6 @@
option('hexagon_idef_parser', type : 'boolean', value : true,
description: 'use idef-parser to automatically generate TCG code for the Hexagon frontend')
+
+option('x86_version', type : 'combo', choices : ['0', '1', '2', '3', '4'], value: '1',
+ description: 'tweak required x86_64 architecture version beyond compiler default')
diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
index 58d49a4..62842d4 100644
--- a/scripts/meson-buildoptions.sh
+++ b/scripts/meson-buildoptions.sh
@@ -82,6 +82,8 @@
printf "%s\n" ' --with-suffix=VALUE Suffix for QEMU data/modules/config directories'
printf "%s\n" ' (can be empty) [qemu]'
printf "%s\n" ' --with-trace-file=VALUE Trace file prefix for simple backend [trace]'
+ printf "%s\n" ' --x86-version=CHOICE tweak required x86_64 architecture version beyond'
+ printf "%s\n" ' compiler default [1] (choices: 0/1/2/3)'
printf "%s\n" ''
printf "%s\n" 'Optional features, enabled with --enable-FEATURE and'
printf "%s\n" 'disabled with --disable-FEATURE, default is enabled if available'
@@ -552,6 +554,7 @@
--disable-werror) printf "%s" -Dwerror=false ;;
--enable-whpx) printf "%s" -Dwhpx=enabled ;;
--disable-whpx) printf "%s" -Dwhpx=disabled ;;
+ --x86-version=*) quote_sh "-Dx86_version=$2" ;;
--enable-xen) printf "%s" -Dxen=enabled ;;
--disable-xen) printf "%s" -Dxen=disabled ;;
--enable-xen-pci-passthrough) printf "%s" -Dxen_pci_passthrough=enabled ;;
