aboutsummaryrefslogtreecommitdiff
path: root/util/bufferiszero.c
AgeCommit message (Collapse)Author
2020-04-01util/bufferiszero: improve avx2 acceleratorRobert Hoo
By increasing avx2 length_to_accel to 128, we can simplify its logic and reduce a branch. The authorship of this patch actually belongs to Richard Henderson <richard.henderson@linaro.org>, I just fixed a boundary case on his original patch. Suggested-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Message-Id: <1585119021-46593-2-git-send-email-robert.hu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-01util/bufferiszero: assign length_to_accel value for each accelerator caseRobert Hoo
Because in unit test, init_accel() will be called several times, each with different accelerator type. Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Message-Id: <1585119021-46593-1-git-send-email-robert.hu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16util: add util function buffer_zero_avx512()Robert Hoo
And intialize buffer_is_zero() with it, when Intel AVX512F is available on host. This function utilizes Intel AVX512 fundamental instructions which is faster than its implementation with AVX2 (in my unit test, with 4K buffer, on CascadeLake SP, ~36% faster, buffer_zero_avx512() V.S. buffer_zero_avx2()). Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-12Include qemu-common.h exactly where neededMarkus Armbruster
No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
2017-07-24util: Introduce include/qemu/cpuid.hRichard Henderson
Clang 3.9 passes the CONFIG_AVX2_OPT configure test. However, the supplied <cpuid.h> does not contain the bit_AVX2 define that we use when detecting whether the routine can be enabled. Introduce a qemu-specific header that uses the compiler's definition of __cpuid et al, but supplies any missing bit_* definitions needed. This avoids introducing any extra ifdefs to util/bufferiszero.c, and allows quite a few to be removed from tcg/i386/tcg-target.inc.c. Signed-off-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 20170719044018.18063-1-rth@twiddle.net Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-09-14cutils: Rewrite x86 buffer zero checkingRichard Henderson
Handle alignment of buffers, so that the vector paths can be used more often. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1473800239-13841-1-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Add generic prefetchRichard Henderson
There's no real knowledge of the cacheline size, just prefetching one loop ahead. Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-7-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Add SSE4 versionPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Add test for buffer_is_zeroRichard Henderson
Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-6-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Remove ppc buffer zero checkingRichard Henderson
For ppc64le, gcc6 does extremely poorly with the Altivec code. Moreover, on POWER7 and POWER8, a hand-optimized Altivec version turns out to be no faster than the revised integer version, and therefore not worth the effort. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Remove aarch64 buffer zero checkingRichard Henderson
The revised integer version is 4 times faster than the neon version on an AppliedMicro Mustang. Even with hand scheduling and additional unrolling I cannot make any neon version run as fast as the integer. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Rearrange buffer_is_zero accelerationRichard Henderson
Allow selection of several acceleration functions based on the size and alignment of the buffer. Do not require ifunc support for AVX2 acceleration. Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-5-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Export only buffer_is_zeroRichard Henderson
Since the two users don't make use of the returned offset, beyond ensuring that the entire buffer is zero, consider the can_use_buffer_find_nonzero_offset and buffer_find_nonzero_offset functions internal. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-4-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Remove SPLAT macroRichard Henderson
This is unused and complicates the vector interface. Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-3-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cutils: Move buffer_is_zero and subroutines to a new fileRichard Henderson
Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1472496380-19706-2-git-send-email-rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
generated by cgit v1.2.3 (git 2.26.2) at 2025-01-09 03:29:14 +0000