[dev.ssa] cmd/compile: report better line numbers for Unimplemented/Fatal

If a failure occurs in SSA processing, we always report the
last line of the function we're compiling.  Modify the callbacks
from SSA to the GC compiler so we can pass a line number back
and use it in Fatalf.

Change-Id: Ifbfad50d5e167e997e0a96f0775bcc369f5c397e
Reviewed-on: https://go-review.googlesource.com/18599
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>

src/cmd/compile/internal/gc/ssa.go

@@ -130,7 +130,7 @@ func buildssa(fn *Node) *ssa.Func {
 	if name == os.Getenv("GOSSAFUNC") {
 		// TODO: tempfile? it is handy to have the location
 		// of this file be stable, so you can just reload in the browser.
-		s.config.HTML = ssa.NewHTMLWriter("ssa.html", &s, name)
+		s.config.HTML = ssa.NewHTMLWriter("ssa.html", s.config, name)
 		// TODO: generate and print a mapping from nodes to values and blocks
 	}
 	defer func() {
@@ -320,9 +320,11 @@ func (s *state) label(sym *Sym) *ssaLabel {
 	return lab
 }
 
-func (s *state) Logf(msg string, args ...interface{})            { s.config.Logf(msg, args...) }
-func (s *state) Fatalf(msg string, args ...interface{})          { s.config.Fatalf(msg, args...) }
-func (s *state) Unimplementedf(msg string, args ...interface{})  { s.config.Unimplementedf(msg, args...) }
+func (s *state) Logf(msg string, args ...interface{})   { s.config.Logf(msg, args...) }
+func (s *state) Fatalf(msg string, args ...interface{}) { s.config.Fatalf(s.peekLine(), msg, args...) }
+func (s *state) Unimplementedf(msg string, args ...interface{}) {
+	s.config.Unimplementedf(s.peekLine(), msg, args...)
+}
 func (s *state) Warnl(line int, msg string, args ...interface{}) { s.config.Warnl(line, msg, args...) }
 func (s *state) Debug_checknil() bool                            { return s.config.Debug_checknil() }
 
@@ -4594,17 +4596,19 @@ func (e *ssaExport) Logf(msg string, args ...interface{}) {
 }
 
 // Fatal reports a compiler error and exits.
-func (e *ssaExport) Fatalf(msg string, args ...interface{}) {
+func (e *ssaExport) Fatalf(line int32, msg string, args ...interface{}) {
 	// If e was marked as unimplemented, anything could happen. Ignore.
 	if !e.unimplemented {
+		lineno = line
 		Fatalf(msg, args...)
 	}
 }
 
 // Unimplemented reports that the function cannot be compiled.
 // It will be removed once SSA work is complete.
-func (e *ssaExport) Unimplementedf(msg string, args ...interface{}) {
+func (e *ssaExport) Unimplementedf(line int32, msg string, args ...interface{}) {
 	if e.mustImplement {
+		lineno = line
 		Fatalf(msg, args...)
 	}
 	const alwaysLog = false // enable to calculate top unimplemented features

src/cmd/compile/internal/ssa/config.go

@@ -44,11 +44,11 @@ type Logger interface {
 	Logf(string, ...interface{})
 
 	// Fatal reports a compiler error and exits.
-	Fatalf(string, ...interface{})
+	Fatalf(line int32, msg string, args ...interface{})
 
 	// Unimplemented reports that the function cannot be compiled.
 	// It will be removed once SSA work is complete.
-	Unimplementedf(msg string, args ...interface{})
+	Unimplementedf(line int32, msg string, args ...interface{})
 
 	// Warnl writes compiler messages in the form expected by "errorcheck" tests
 	Warnl(line int, fmt_ string, args ...interface{})
@@ -91,7 +91,7 @@ func NewConfig(arch string, fe Frontend, ctxt *obj.Link) *Config {
 		c.lowerBlock = rewriteBlockAMD64
 		c.lowerValue = rewriteValueAMD64 // TODO(khr): full 32-bit support
 	default:
-		fe.Unimplementedf("arch %s not implemented", arch)
+		fe.Unimplementedf(0, "arch %s not implemented", arch)
 	}
 	c.ctxt = ctxt
 
@@ -106,9 +106,11 @@ func (c *Config) NewFunc() *Func {
 	return &Func{Config: c, NamedValues: map[LocalSlot][]*Value{}}
 }
 
-func (c *Config) Logf(msg string, args ...interface{})            { c.fe.Logf(msg, args...) }
-func (c *Config) Fatalf(msg string, args ...interface{})          { c.fe.Fatalf(msg, args...) }
-func (c *Config) Unimplementedf(msg string, args ...interface{})  { c.fe.Unimplementedf(msg, args...) }
+func (c *Config) Logf(msg string, args ...interface{})               { c.fe.Logf(msg, args...) }
+func (c *Config) Fatalf(line int32, msg string, args ...interface{}) { c.fe.Fatalf(line, msg, args...) }
+func (c *Config) Unimplementedf(line int32, msg string, args ...interface{}) {
+	c.fe.Unimplementedf(line, msg, args...)
+}
 func (c *Config) Warnl(line int, msg string, args ...interface{}) { c.fe.Warnl(line, msg, args...) }
 func (c *Config) Debug_checknil() bool                            { return c.fe.Debug_checknil() }
 

src/cmd/compile/internal/ssa/export_test.go

@@ -32,9 +32,12 @@ func (DummyFrontend) Auto(t Type) GCNode {
 	return nil
 }
 
-func (d DummyFrontend) Logf(msg string, args ...interface{})            { d.t.Logf(msg, args...) }
-func (d DummyFrontend) Fatalf(msg string, args ...interface{})          { d.t.Fatalf(msg, args...) }
-func (d DummyFrontend) Unimplementedf(msg string, args ...interface{})  { d.t.Fatalf(msg, args...) }
+func (d DummyFrontend) Logf(msg string, args ...interface{}) { d.t.Logf(msg, args...) }
+
+func (d DummyFrontend) Fatalf(line int32, msg string, args ...interface{}) { d.t.Fatalf(msg, args...) }
+func (d DummyFrontend) Unimplementedf(line int32, msg string, args ...interface{}) {
+	d.t.Fatalf(msg, args...)
+}
 func (d DummyFrontend) Warnl(line int, msg string, args ...interface{}) { d.t.Logf(msg, args...) }
 func (d DummyFrontend) Debug_checknil() bool                            { return false }
 

src/cmd/compile/internal/ssa/func.go

@@ -305,6 +305,8 @@ func (f *Func) ConstFloat64(line int32, t Type, c float64) *Value {
 	return f.Entry.NewValue0I(line, OpConst64F, t, int64(math.Float64bits(c)))
 }
 
-func (f *Func) Logf(msg string, args ...interface{})           { f.Config.Logf(msg, args...) }
-func (f *Func) Fatalf(msg string, args ...interface{})         { f.Config.Fatalf(msg, args...) }
-func (f *Func) Unimplementedf(msg string, args ...interface{}) { f.Config.Unimplementedf(msg, args...) }
+func (f *Func) Logf(msg string, args ...interface{})   { f.Config.Logf(msg, args...) }
+func (f *Func) Fatalf(msg string, args ...interface{}) { f.Config.Fatalf(f.Entry.Line, msg, args...) }
+func (f *Func) Unimplementedf(msg string, args ...interface{}) {
+	f.Config.Unimplementedf(f.Entry.Line, msg, args...)
+}

src/cmd/compile/internal/ssa/html.go

@@ -20,7 +20,7 @@ type HTMLWriter struct {
 func NewHTMLWriter(path string, logger Logger, funcname string) *HTMLWriter {
 	out, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
 	if err != nil {
-		logger.Fatalf("%v", err)
+		logger.Fatalf(0, "%v", err)
 	}
 	html := HTMLWriter{File: out, Logger: logger}
 	html.start(funcname)
@@ -326,13 +326,13 @@ func (w *HTMLWriter) WriteColumn(title string, html string) {
 
 func (w *HTMLWriter) Printf(msg string, v ...interface{}) {
 	if _, err := fmt.Fprintf(w.File, msg, v...); err != nil {
-		w.Fatalf("%v", err)
+		w.Fatalf(0, "%v", err)
 	}
 }
 
 func (w *HTMLWriter) WriteString(s string) {
 	if _, err := w.File.WriteString(s); err != nil {
-		w.Fatalf("%v", err)
+		w.Fatalf(0, "%v", err)
 	}
 }
 

src/cmd/compile/internal/ssa/value.go

@@ -135,9 +135,13 @@ func (v *Value) copyInto(b *Block) *Value {
 	return c
 }
 
-func (v *Value) Logf(msg string, args ...interface{})           { v.Block.Logf(msg, args...) }
-func (v *Value) Fatalf(msg string, args ...interface{})         { v.Block.Fatalf(msg, args...) }
-func (v *Value) Unimplementedf(msg string, args ...interface{}) { v.Block.Unimplementedf(msg, args...) }
+func (v *Value) Logf(msg string, args ...interface{}) { v.Block.Logf(msg, args...) }
+func (v *Value) Fatalf(msg string, args ...interface{}) {
+	v.Block.Func.Config.Fatalf(v.Line, msg, args...)
+}
+func (v *Value) Unimplementedf(msg string, args ...interface{}) {
+	v.Block.Func.Config.Unimplementedf(v.Line, msg, args...)
+}
 
 // ExternSymbol is an aux value that encodes a variable's
 // constant offset from the static base pointer.