build: support comments in functions (#41)

tests/fmt/asm.go

@@ -0,0 +1,26 @@
+// +build ignore
+
+package main
+
+import (
+	. "github.com/mmcloughlin/avo/build"
+	. "github.com/mmcloughlin/avo/reg"
+)
+
+func main() {
+	TEXT("Formatting", NOSPLIT, "func()")
+	Doc("Formatting contains various cases to test the formatter.")
+
+	ADDQ(R8, R8)
+	Comment("One comment line between instructions.")
+	ADDQ(R8, R8)
+
+	Comment("Comment before label.")
+	Label("label")
+	Comment("Comment after label.")
+	ADDQ(R8, R8)
+
+	RET()
+
+	Generate()
+}

tests/fmt/fmt.s

@@ -0,0 +1,16 @@
+// Code generated by command: go run asm.go -out fmt.s -stubs stub.go. DO NOT EDIT.
+
+#include "textflag.h"
+
+// func Formatting()
+TEXT ·Formatting(SB), NOSPLIT, $0
+	ADDQ R8, R8
+
+	// One comment line between instructions.
+	ADDQ R8, R8
+
+	// Comment before label.
+label:
+	// Comment after label.
+	ADDQ R8, R8
+	RET

tests/fmt/gen.go

@@ -0,0 +1,4 @@
+// Package fmt tests assembly printer formatting.
+package fmt
+
+//go:generate go run asm.go -out fmt.s -stubs stub.go

tests/fmt/stub.go

@@ -0,0 +1,6 @@
+// Code generated by command: go run asm.go -out fmt.s -stubs stub.go. DO NOT EDIT.
+
+package fmt
+
+// Formatting contains various cases to test the formatter.
+func Formatting()