utils: Adopt to use RVV extentions for RISC-V

Signed-off-by: Hiroshi Hatake <[email protected]>

src/flb_utils.c

@@ -801,6 +801,11 @@ int flb_utils_write_str(char *buf, int *off, size_t size, const char *str, size_
     off_t offset = 0;
     char tmp[16];
     char *p;
+#if defined(FLB_SIMD_RVV)
+    const size_t inst_len = RVV_VEC_INST_LEN;
+#else
+    const size_t inst_len = sizeof(flb_vector8);
+#endif
 
     /* to encode codepoints > 0xFFFF */
     uint16_t high;
@@ -816,10 +821,10 @@ int flb_utils_write_str(char *buf, int *off, size_t size, const char *str, size_
     p = buf + *off;
 
     /* align length to the nearest multiple of the vector size for safe SIMD processing */
-    vlen = str_len & ~(sizeof(flb_vector8) - 1);
+    vlen = str_len & ~(inst_len - 1);
     for (i = 0;;) {
         /* SIMD optimization: Process chunk of input string */
-        for (; i < vlen; i += sizeof(flb_vector8)) {
+        for (; i < vlen; i += inst_len) {
             flb_vector8 chunk;
             flb_vector8_load(&chunk, (const uint8_t *)&str[i]);
 
@@ -851,7 +856,7 @@ int flb_utils_write_str(char *buf, int *off, size_t size, const char *str, size_
         }
 
         /* Process remaining characters one by one */
-        for (b = 0; b < sizeof(flb_vector8); b++) {
+        for (b = 0; b < inst_len; b++) {
             if (i >= str_len) {
                 /* all characters has been processed */
                 goto done;