vectorize is_dup_page

is_dup_page is already proceeding in 32-bit chunks.  Changing it
to 16 bytes using Altivec or SSE is easy.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Paolo Bonzini 2011-12-23 16:17:26 +01:00 committed by Anthony Liguori
parent 1ba1f2e319
commit 8600361542
1 changed files with 22 additions and 6 deletions

View File

@ -95,14 +95,30 @@ const uint32_t arch_type = QEMU_ARCH;
#define RAM_SAVE_FLAG_EOS 0x10
#define RAM_SAVE_FLAG_CONTINUE 0x20
static int is_dup_page(uint8_t *page, uint8_t ch)
#ifdef __ALTIVEC__
#include <altivec.h>
#define VECTYPE vector unsigned char
#define SPLAT(p) vec_splat(vec_ld(0, p), 0)
#define ALL_EQ(v1, v2) vec_all_eq(v1, v2)
#elif defined __SSE2__
#include <emmintrin.h>
#define VECTYPE __m128i
#define SPLAT(p) _mm_set1_epi8(*(p))
#define ALL_EQ(v1, v2) (_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)) == 0xFFFF)
#else
#define VECTYPE unsigned long
#define SPLAT(p) (*(p) * (~0UL / 255))
#define ALL_EQ(v1, v2) ((v1) == (v2))
#endif
static int is_dup_page(uint8_t *page)
{
uint32_t val = ch << 24 | ch << 16 | ch << 8 | ch;
uint32_t *array = (uint32_t *)page;
VECTYPE *p = (VECTYPE *)page;
VECTYPE val = SPLAT(page);
int i;
for (i = 0; i < (TARGET_PAGE_SIZE / 4); i++) {
if (array[i] != val) {
for (i = 0; i < TARGET_PAGE_SIZE / sizeof(VECTYPE); i++) {
if (!ALL_EQ(val, p[i])) {
return 0;
}
}
@ -134,7 +150,7 @@ static int ram_save_block(QEMUFile *f)
p = memory_region_get_ram_ptr(mr) + offset;
if (is_dup_page(p, *p)) {
if (is_dup_page(p)) {
qemu_put_be64(f, offset | cont | RAM_SAVE_FLAG_COMPRESS);
if (!cont) {
qemu_put_byte(f, strlen(block->idstr));