Hi all,
Currently SLP vectorization can build SLP trees starting from reductions or
from group stores. This patch adds a third starting point: vector constructors.
For the following aarch64 test case (compiled with -O3 -fno-vect-cost-model):
char g_d[1024], g_s1[1024], g_s2[1024];
void test_loop(void)
{
char d = g_d, s1 = g_s1, *s2 = g_s2;
for ( int y = 0; y < 128; y++ )
{
for ( int x = 0; x < 16; x++ )
d[x] = s1[x] + s2[x];
d += 16;
}
}
before patch: test_loop: .LFB0: .cfi_startproc adrp x0, g_s1 adrp x2, g_s2 add
x3, x0, :lo12:g_s1 add x4, x2, :lo12:g_s2 ldrb w7, [x2, #:lo12:g_s2] ldrb w1,
[x0, #:lo12:g_s1] adrp x0, g_d ldrb w6, [x4, 1] add x0, x0, :lo12:g_d ldrb w5,
[x3, 1] add w1, w1, w7 fmov s0, w1 ldrb w7, [x4, 2] add w5, w5, w6 ldrb w1,
[x3, 2] ldrb w6, [x4, 3] add x2, x0, 2048 ins v0.b[1], w5 add w1, w1, w7 ldrb
w7, [x3, 3] ldrb w5, [x4, 4] add w7, w7, w6 ldrb w6, [x3, 4] ins v0.b[2], w1
ldrb w8, [x4, 5] add w6, w6, w5 ldrb w5, [x3, 5] ldrb w9, [x4, 6] add w5, w5,
w8 ldrb w1, [x3, 6] ins v0.b[3], w7 ldrb w8, [x4, 7] add w1, w1, w9 ldrb w11,
[x3, 7] ldrb w7, [x4, 8] add w11, w11, w8 ldrb w10, [x3, 8] ins v0.b[4], w6
ldrb w8, [x4, 9] add w10, w10, w7 ldrb w9, [x3, 9] ldrb w7, [x4, 10] add w9,
w9, w8 ldrb w8, [x3, 10] ins v0.b[5], w5 ldrb w6, [x4, 11] add w8, w8, w7 ldrb
w7, [x3, 11] ldrb w5, [x4, 12] add w7, w7, w6 ldrb w6, [x3, 12] ins v0.b[6], w1
ldrb w12, [x4, 13] add w6, w6, w5 ldrb w5, [x3, 13] ldrb w1, [x3, 14] add w5,
w5, w12 ldrb w13, [x4, 14] ins v0.b[7], w11 ldrb w12, [x4, 15] add w4, w1, w13
ldrb w1, [x3, 15] add w1, w1, w12 ins v0.b[8], w10 ins v0.b[9], w9 ins
v0.b[10], w8 ins v0.b[11], w7 ins v0.b[12], w6 ins v0.b[13], w5 ins v0.b[14],
w4 ins v0.b[15], w1 .p2align 3,,7 .L2: str q0, [x0], 16 cmp x2, x0 bne .L2 ret
.cfi_endproc .LFE0:
After patch:
test_loop: .LFB0: .cfi_startproc adrp x3, g_s1 adrp x2, g_s2 add x3, x3,
:lo12:g_s1 add x2, x2, :lo12:g_s2 adrp x0, g_d add x0, x0, :lo12:g_d add x1,
x0, 2048 ldr q1, [x2] ldr q0, [x3] add v0.16b, v0.16b, v1.16b .p2align 3,,7
.L2: str q0, [x0], 16 cmp x0, x1 bne .L2 ret .cfi_endproc .LFE0:
bootstrapped and tested on aarch64-none-linux-gnu
