1 files changed, 53 insertions, 0 deletions
diff --git a/euler/source/euler/gcc.asm b/euler/source/euler/gcc.asm
new file mode 100644
index 0000000..6fc6fd5
--- /dev/null
+++ b/euler/source/euler/gcc.asm
@@ -0,0 +1,53 @@
+bits 64
+
+global strlen
+
+section .text
+
+strlen:
+  xor rax, rax
+.loop:
+  mov rdx, qword [rdi]
+  test edx, 0xff
+  jz .plus0
+  test edx, 0xff00
+  jz .plus1
+  test edx, 0xff0000
+  jz .plus2
+  test edx, 0xff000000
+  jz .plus3
+  shr rdx, 32
+  test edx, 0xff
+  jz .plus4
+  test edx, 0xff00
+  jz .plus5
+  test edx, 0xff0000
+  jz .plus6
+  test edx, 0xff000000
+  jz .plus7
+  add rax, 8
+  add rdi, 8
+  jmp .loop
+.plus0:
+  ret
+.plus1:
+  add rax, 1
+  ret
+.plus2:
+  add rax, 2
+  ret
+.plus3:
+  add rax, 3
+  ret
+.plus4:
+  add rax, 4
+  ret
+.plus5:
+  add rax, 5
+  ret
+.plus6:
+  add rax, 6
+  ret
+.plus7:
+  add rax, 7
+  ret