Add Printer hook enabling custom user defined file output like -stubs

build/global.go

@@ -2,13 +2,15 @@ package build
 
 import (
 	"flag"
+	"io"
 	"os"
 
 	"github.com/mmcloughlin/avo/attr"
 	"github.com/mmcloughlin/avo/buildtags"
 	"github.com/mmcloughlin/avo/gotypes"
 	"github.com/mmcloughlin/avo/ir"
 	"github.com/mmcloughlin/avo/operand"
+	"github.com/mmcloughlin/avo/printer"
 	"github.com/mmcloughlin/avo/reg"
 )
 
@@ -35,7 +37,8 @@ func DATA(offset int, v operand.Constant) {
 	ctx.AddDatum(offset, v)
 }
 
-var flags = NewFlags(flag.CommandLine)
+var flagSet = flag.CommandLine
+var flags = NewFlags(flagSet)
 
 // Generate builds and compiles the avo file built with the global context. This
 // should be the final line of any avo program. Configuration is determined from command-line flags.
@@ -161,3 +164,10 @@ func ConstData(name string, v operand.Constant) operand.Mem { return ctx.ConstDa
 
 // Instruction adds an instruction to the active function.
 func Instruction(i *ir.Instruction) { ctx.Instruction(i) }
+
+// AddPrinter registers a custom printer
+func AddPrinter(flag, desc string, pB printer.Builder, dflt io.WriteCloser) {
+	pV := newPrinterValue(pB, dflt)
+	flagSet.Var(pV, flag, desc)
+	flags.printers = append(flags.printers, pV)
+}

internal/gen/asmtest.go

@@ -7,7 +7,6 @@ import (
 	"strings"
 
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
@@ -16,7 +15,7 @@ type asmtest struct {
 	sym   string // reference to the test function symbol
 	rel8  string // label to be used for near jumps
 	rel32 string // label for far jumps
-	prnt.Generator
+	printer.Generator
 }
 
 // NewAsmTest prints one massive assembly function containing a line for every

internal/gen/build.go

@@ -5,13 +5,12 @@ import (
 
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type build struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewBuild builds a printer that will generate instruction functions in the

internal/gen/buildtest.go

@@ -3,13 +3,12 @@ package gen
 import (
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type buildtest struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewBuildTest autogenerates tests for instruction methods on the build

internal/gen/ctors.go

@@ -3,13 +3,12 @@ package gen
 import (
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type ctors struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewCtors will build instruction constructors.  Each constructor delegates to

internal/gen/ctorstest.go

@@ -7,13 +7,12 @@ import (
 
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type ctorstest struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewCtorsTest autogenerates tests for the constructors build by NewCtors.
@@ -55,7 +54,7 @@ func (c *ctorstest) function(fn *api.Function) {
 
 type ctorsstress struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewCtorsStress autogenerates stress tests for instruction constructors.
@@ -102,7 +101,7 @@ func (c *ctorsstress) function(fn *api.Function) {
 
 type ctorsbench struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewCtorsBench autogenerates a benchmark for the instruction constructors.

internal/gen/godata.go

@@ -3,13 +3,12 @@ package gen
 import (
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type godata struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewGoData writes a Go variable containing the instructions database. This is
@@ -89,7 +88,7 @@ func (g *godata) Generate(is []inst.Instruction) ([]byte, error) {
 
 type godatatest struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewGoDataTest writes a test case to confirm that NewGoData faithfully

internal/gen/mov.go

@@ -7,13 +7,12 @@ import (
 
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type mov struct {
 	cfg printer.Config
-	prnt.Generator
+	printer.Generator
 }
 
 // NewMOV generates a function that will auto-select the correct MOV instruction

internal/gen/optab.go

@@ -8,12 +8,11 @@ import (
 
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/printer"
 )
 
 type optab struct {
-	prnt.Generator
+	printer.Generator
 
 	cfg printer.Config
 

internal/gen/testing.go

@@ -3,12 +3,12 @@ package gen
 import (
 	"github.com/mmcloughlin/avo/internal/api"
 	"github.com/mmcloughlin/avo/internal/inst"
-	"github.com/mmcloughlin/avo/internal/prnt"
+	"github.com/mmcloughlin/avo/printer"
 )
 
 // DeclareTestArguments prints a block of variables declaring a valid operand of
 // each operand type.
-func DeclareTestArguments(g *prnt.Generator) {
+func DeclareTestArguments(g *printer.Generator) {
 	g.Printf("var (\n")
 	for _, arg := range validArgs {
 		g.Printf("\t%s operand.Op = %s\n", TestArgumentName(arg.Type), arg.Code)

internal/prnt/printer.go → printer/generator.go

@@ -1,5 +1,5 @@
-// Package prnt provides common functionality for code generators.
-package prnt
+// Package printer implements printing of avo files in various formats.
+package printer
 
 import (
 	"bytes"

printer/goasm.go

@@ -5,7 +5,6 @@ import (
 	"strings"
 
 	"github.com/mmcloughlin/avo/buildtags"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/ir"
 	"github.com/mmcloughlin/avo/operand"
 )
@@ -15,7 +14,7 @@ const dot = "\u00b7"
 
 type goasm struct {
 	cfg Config
-	prnt.Generator
+	Generator
 
 	instructions []*ir.Instruction
 	clear        bool

printer/stubs.go

@@ -4,13 +4,12 @@ import (
 	"go/format"
 
 	"github.com/mmcloughlin/avo/buildtags"
-	"github.com/mmcloughlin/avo/internal/prnt"
 	"github.com/mmcloughlin/avo/ir"
 )
 
 type stubs struct {
 	cfg Config
-	prnt.Generator
+	Generator
 }
 
 // NewStubs constructs a printer for writing stub function declarations.

tests/thirdparty/make_workflow.go

@@ -10,7 +10,7 @@ import (
 	"path/filepath"
 	"runtime"
 
-	"github.com/mmcloughlin/avo/internal/prnt"
+	"github.com/mmcloughlin/avo/printer"
 	"github.com/mmcloughlin/avo/tests/thirdparty"
 )
 
@@ -64,7 +64,7 @@ func mainerr() error {
 }
 
 func GenerateWorkflow(s *thirdparty.Suite) ([]byte, error) {
-	g := &prnt.Generator{}
+	g := &printer.Generator{}
 	g.SetIndentString("  ")
 
 	_, self, _, _ := runtime.Caller(0)