OpenBLAS/kernel/riscv64/nrm2_rvv.c

213 lines
9.2 KiB
C

/***************************************************************************
Copyright (c) 2022, The OpenBLAS Project
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
3. Neither the name of the OpenBLAS project nor the names of
its contributors may be used to endorse or promote products
derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBLAS PROJECT OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*****************************************************************************/
#include "common.h"
#if defined(DOUBLE)
#define VSETVL __riscv_vsetvl_e64m4
#define FLOAT_V_T vfloat64m4_t
#define FLOAT_V_T_M1 vfloat64m1_t
#define VLEV_FLOAT __riscv_vle64_v_f64m4
#define VLSEV_FLOAT __riscv_vlse64_v_f64m4
#define VFMVVF_FLOAT __riscv_vfmv_v_f_f64m4
#define VFMVSF_FLOAT __riscv_vfmv_s_f_f64m4
#define VFMVVF_FLOAT_M1 __riscv_vfmv_v_f_f64m1
#define MASK_T vbool16_t
#define VFABS __riscv_vfabs_v_f64m4
#define VMFNE __riscv_vmfne_vf_f64m4_b16
#define VMFGT __riscv_vmfgt_vv_f64m4_b16
#define VMFEQ __riscv_vmfeq_vf_f64m4_b16
#define VCPOP __riscv_vcpop_m_b16
#define VFREDMAX __riscv_vfredmax_vs_f64m4_f64m1
#define VFREDMIN __riscv_vfredmin_vs_f64m4_f64m1
#define VFIRST __riscv_vfirst_m_b16
#define VRGATHER __riscv_vrgather_vx_f64m4
#define VFDIV __riscv_vfdiv_vv_f64m4
#define VFDIV_M __riscv_vfdiv_vv_f64m4_mu
#define VFMUL __riscv_vfmul_vv_f64m4
#define VFMUL_M __riscv_vfmul_vv_f64m4_mu
#define VFMACC __riscv_vfmacc_vv_f64m4
#define VFMACC_M __riscv_vfmacc_vv_f64m4_mu
#define VMSBF __riscv_vmsbf_m_b16
#define VMSOF __riscv_vmsof_m_b16
#define VMAND __riscv_vmand_mm_b16
#define VMANDN __riscv_vmand_mm_b16
#define VFREDSUM __riscv_vfredusum_vs_f64m4_f64m1
#define VMERGE __riscv_vmerge_vvm_f64m4
#define VSEV_FLOAT __riscv_vse64_v_f64m4
#define EXTRACT_FLOAT0_V(v) __riscv_vfmv_f_s_f64m4_f64(v)
#define ABS fabs
#else
#define VSETVL __riscv_vsetvl_e32m4
#define FLOAT_V_T vfloat32m4_t
#define FLOAT_V_T_M1 vfloat32m1_t
#define VLEV_FLOAT __riscv_vle32_v_f32m4
#define VLSEV_FLOAT __riscv_vlse32_v_f32m4
#define VFMVVF_FLOAT __riscv_vfmv_v_f_f32m4
#define VFMVSF_FLOAT __riscv_vfmv_s_f_f32m4
#define VFMVVF_FLOAT_M1 __riscv_vfmv_v_f_f32m1
#define MASK_T vbool8_t
#define VFABS __riscv_vfabs_v_f32m4
#define VMFNE __riscv_vmfne_vf_f32m4_b8
#define VMFGT __riscv_vmfgt_vv_f32m4_b8
#define VMFEQ __riscv_vmfeq_vf_f32m4_b8
#define VCPOP __riscv_vcpop_m_b8
#define VFREDMAX __riscv_vfredmax_vs_f32m4_f32m1
#define VFREDMIN __riscv_vfredmin_vs_f32m4_f32m1
#define VFIRST __riscv_vfirst_m_b8
#define VRGATHER __riscv_vrgather_vx_f32m4
#define VFDIV __riscv_vfdiv_vv_f32m4
#define VFDIV_M __riscv_vfdiv_vv_f32m4_mu
#define VFMUL __riscv_vfmul_vv_f32m4
#define VFMUL_M __riscv_vfmul_vv_f32m4_mu
#define VFMACC __riscv_vfmacc_vv_f32m4
#define VFMACC_M __riscv_vfmacc_vv_f32m4_mu
#define VMSBF __riscv_vmsbf_m_b8
#define VMSOF __riscv_vmsof_m_b8
#define VMAND __riscv_vmand_mm_b8
#define VMANDN __riscv_vmand_mm_b8
#define VFREDSUM __riscv_vfredusum_vs_f32m4_f32m1
#define VMERGE __riscv_vmerge_vvm_f32m4
#define VSEV_FLOAT __riscv_vse32_v_f32m4
#define EXTRACT_FLOAT0_V(v) __riscv_vfmv_f_s_f32m4_f32(v)
#define ABS fabsf
#endif
FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x)
{
BLASLONG i=0;
if (n <= 0 || inc_x == 0) return(0.0);
if(n == 1) return (ABS(x[0]));
unsigned int gvl = 0;
MASK_T nonzero_mask;
MASK_T scale_mask;
gvl = VSETVL(n);
FLOAT_V_T v0;
FLOAT_V_T v_ssq = VFMVVF_FLOAT(0, gvl);
FLOAT_V_T v_scale = VFMVVF_FLOAT(0, gvl);
FLOAT scale = 0;
FLOAT ssq = 0;
unsigned int stride_x = inc_x * sizeof(FLOAT);
int idx = 0;
if( n >= gvl && inc_x > 0 ) // don't pay overheads if we're not doing useful work
{
for(i=0; i<n/gvl; i++){
v0 = VLSEV_FLOAT( &x[idx], stride_x, gvl );
nonzero_mask = VMFNE( v0, 0, gvl );
v0 = VFABS( v0, gvl );
scale_mask = VMFGT( v0, v_scale, gvl );
// assume scale changes are relatively infrequent
// unclear if the vcpop+branch is actually a win
// since the operations being skipped are predicated anyway
// need profiling to confirm
if( VCPOP(scale_mask, gvl) )
{
v_scale = VFDIV_M( scale_mask, v_scale, v_scale, v0, gvl );
v_scale = VFMUL_M( scale_mask, v_scale, v_scale, v_scale, gvl );
v_ssq = VFMUL_M( scale_mask, v_ssq, v_ssq, v_scale, gvl );
v_scale = VMERGE( v_scale, v0, scale_mask, gvl );
}
v0 = VFDIV_M( nonzero_mask, v0, v0, v_scale, gvl );
v_ssq = VFMACC_M( nonzero_mask, v_ssq, v0, v0, gvl );
idx += inc_x * gvl;
}
// we have gvl elements which we accumulated independently, with independent scales
// we need to combine these
// naive sort so we process small values first to avoid losing information
// could use vector sort extensions where available, but we're dealing with gvl elts at most
FLOAT * out_ssq = alloca(gvl*sizeof(FLOAT));
FLOAT * out_scale = alloca(gvl*sizeof(FLOAT));
VSEV_FLOAT( out_ssq, v_ssq, gvl );
VSEV_FLOAT( out_scale, v_scale, gvl );
for( int a = 0; a < (gvl-1); ++a )
{
int smallest = a;
for( size_t b = a+1; b < gvl; ++b )
if( out_scale[b] < out_scale[smallest] )
smallest = b;
if( smallest != a )
{
FLOAT tmp1 = out_ssq[a];
FLOAT tmp2 = out_scale[a];
out_ssq[a] = out_ssq[smallest];
out_scale[a] = out_scale[smallest];
out_ssq[smallest] = tmp1;
out_scale[smallest] = tmp2;
}
}
int a = 0;
while( a<gvl && out_scale[a] == 0 )
++a;
if( a < gvl )
{
ssq = out_ssq[a];
scale = out_scale[a];
++a;
for( ; a < gvl; ++a )
{
ssq = ssq * ( scale / out_scale[a] ) * ( scale / out_scale[a] ) + out_ssq[a];
scale = out_scale[a];
}
}
}
//finish any tail using scalar ops
i*=gvl*inc_x;
n*=inc_x;
while(abs(i) < abs(n)){
if ( x[i] != 0.0 ){
FLOAT absxi = ABS( x[i] );
if ( scale < absxi ){
ssq = 1 + ssq * ( scale / absxi ) * ( scale / absxi );
scale = absxi ;
}
else{
ssq += ( absxi/scale ) * ( absxi/scale );
}
}
i += inc_x;
}
return(scale * sqrt(ssq));
}