feat(asm): symbol-valued DATA, division slash in symbols and plain semicolons

Assisted-by: GLM 5.3 Flash

testdata/verify/divslash_amd64.s

@@ -0,0 +1,19 @@
+#include "textflag.h"
+
+// The kernel exercises the U+2215 DIVISION SLASH inside a symbol's package
+// path: internal∕runtime∕atomic·Xchg, the spelling sync/atomic/asm.s uses.
+// The middle dot (U+00B7) still separates the package path from the name.
+
+// func swap(a, b int64) int64
+TEXT ·swap(SB), NOSPLIT, $0-24
+	MOVQ a+0(FP), DI
+	MOVQ b+8(FP), SI
+	CALL internal∕runtime∕atomic·Xchg(SB)
+	MOVQ AX, ret+16(FP)
+	RET
+
+// func note() int64
+TEXT ·note(SB), NOSPLIT, $0-8
+	CALL runtime∕debug·SetGCPercent(SB)
+	MOVQ AX, ret+0(FP)
+	RET