1 files changed, 22 insertions, 0 deletions
diff --git a/src/example/strlen.s b/src/example/strlen.s
new file mode 100644
index 0000000..1c3af4b
--- /dev/null
+++ b/src/example/strlen.s
@@ -0,0 +1,22 @@
+    .text
+    .balign 4
+    .global strlen
+# size_t strlen(const char *str)
+# a0 holds *str
+
+strlen:
+    mv a3, a0             # Save start
+loop:
+    vsetvli a1, x0, e8, m8, ta, ma  # Vector of bytes of maximum length
+    vle8ff.v v8, (a3)      # Load bytes
+    csrr a1, vl           # Get bytes read
+    vmseq.vi v0, v8, 0    # Set v0[i] where v8[i] = 0
+    vfirst.m a2, v0       # Find first set bit
+    add a3, a3, a1        # Bump pointer
+    bltz a2, loop         # Not found?
+
+    add a0, a0, a1        # Sum start + bump
+    add a3, a3, a2        # Add index
+    sub a0, a3, a0        # Subtract start address+bump
+
+    ret