https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118175
Bug ID: 118175
Summary: Unable to do auto vectorization for
rv32imafc_zve32f_zvl128b for matrix like c code
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: fanghuaqi at vip dot qq.com
Target Milestone: ---
Hi there,
I tried to compile code like below
#include <stdio.h>
float *matA, *matB, *matC;
int nthreads;
typedef struct{
int id;
int rowsA;
int colsA;
int colsB;
} tArgs;
void * CalculaProdutoMatriz(void *arg) {
int i, j, k;
tArgs *args = (tArgs*) arg;
int rowsA = args->rowsA;
int colsA = args->colsA;
int colsB = args->colsB;
for(i = args->id; i < rowsA; i += 1) {
for(j = 0; j < colsB; j++) {
matC[i * colsB + j] = 0;
for(k = 0; k < colsA; k++) {
matC[i * colsB + j] += matA[i * colsA + k] * matB[k * colsB +
j];
}
}
}
return 0;
}
Compiler options like below
-march=rv32imafc_zve32f_zvl128b -mabi=ilp32f --param=vsetvl-strategy=optim
-Ofast -ftree-vectorize -mrvv-max-lmul=m8 -funroll-all-loops
I thought it could be auto vectorization using latest gcc15, but not, is there
some compiler options are missed?
I also tried with clang 20 using options -march=rv32imafc_zve32f_zvl128b
-mabi=ilp32f -O3 -funroll-loops and it can generate some vector instructions.
And for Arm Cortex R52 with NEON enabled, it also works for gcc options:
-mcpu=cortex-r52 -O3 -ftree-vectorize -funroll-all-loops
You can also check it in this link https://godbolt.org/z/dY1r88d1c
