examples: add sum example (its not pretty)

2018-12-11 23:02:50 -08:00
parent 19d1761694
commit 2189d38d1e
6 changed files with 71 additions and 4 deletions
--- a/examples/sum/sum.s
+++ b/examples/sum/sum.s
@@ -0,0 +1,18 @@
+
+#include "textflag.h"
+
+// func Sum(xs []uint64) uint64
+TEXT ·Sum(SB),0,$0-32
+	MOVQ	xs_base(FP), DX
+	MOVQ	xs_len+8(FP), CX
+	XORQ	AX, AX
+loop:
+	CMPQ	CX, $0x0
+	JE	done
+	ADDQ	(DX), AX
+	ADDQ	$0x8, DX
+	DECQ	CX
+	JMP	loop
+done:
+	MOVQ	AX, ret+24(FP)
+	RET