From 35fb514596b970a73be972fa917fa23ca74f7be6 Mon Sep 17 00:00:00 2001 From: Josh Bleecher Snyder Date: Mon, 10 Aug 2015 12:15:52 -0700 Subject: [PATCH] [dev.ssa] cmd/compile: add HTML SSA printer This is an initial implementation. There are many rough edges and TODOs, which will hopefully be polished out with use. Fixes #12071. Change-Id: I1d6fd5a343063b5200623bceef2c2cfcc885794e Reviewed-on: https://go-review.googlesource.com/13472 Reviewed-by: Keith Randall --- src/cmd/compile/internal/gc/ssa.go | 40 ++ src/cmd/compile/internal/ssa/compile.go | 3 + src/cmd/compile/internal/ssa/config.go | 16 +- src/cmd/compile/internal/ssa/deadcode.go | 17 +- src/cmd/compile/internal/ssa/html.go | 461 +++++++++++++++++++++++ src/cmd/compile/internal/ssa/print.go | 90 +++-- src/cmd/internal/obj/obj.go | 25 +- 7 files changed, 607 insertions(+), 45 deletions(-) create mode 100644 src/cmd/compile/internal/ssa/html.go diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go index c8ec01f5b6..882efc0dae 100644 --- a/src/cmd/compile/internal/gc/ssa.go +++ b/src/cmd/compile/internal/gc/ssa.go @@ -5,7 +5,9 @@ package gc import ( + "bytes" "fmt" + "html" "os" "strings" @@ -40,6 +42,18 @@ func buildssa(fn *Node) (ssafn *ssa.Func, usessa bool) { s.f = s.config.NewFunc() s.f.Name = name + 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) + // TODO: generate and print a mapping from nodes to values and blocks + } + defer func() { + if !usessa { + s.config.HTML.Close() + } + }() + // If SSA support for the function is incomplete, // assume that any panics are due to violated // invariants. Swallow them silently. @@ -1811,6 +1825,30 @@ func genssa(f *ssa.Func, ptxt *obj.Prog, gcargs, gclocals *Sym) { } f.Logf("%s\t%s\n", s, p) } + if f.Config.HTML != nil { + saved := ptxt.Ctxt.LineHist.PrintFilenameOnly + ptxt.Ctxt.LineHist.PrintFilenameOnly = true + var buf bytes.Buffer + buf.WriteString("") + buf.WriteString("
") + for p := ptxt; p != nil; p = p.Link { + buf.WriteString("
") + if v, ok := valueProgs[p]; ok { + buf.WriteString(v.HTML()) + } else if b, ok := blockProgs[p]; ok { + buf.WriteString(b.HTML()) + } + buf.WriteString("
") + buf.WriteString("
") + buf.WriteString(html.EscapeString(p.String())) + buf.WriteString("
") + buf.WriteString("") + } + buf.WriteString("
") + buf.WriteString("") + f.Config.HTML.WriteColumn("genssa", buf.String()) + ptxt.Ctxt.LineHist.PrintFilenameOnly = saved + } } // Emit static data @@ -1834,6 +1872,8 @@ func genssa(f *ssa.Func, ptxt *obj.Prog, gcargs, gclocals *Sym) { ggloblsym(gcargs, 4, obj.RODATA|obj.DUPOK) duint32(gclocals, 0, 0) ggloblsym(gclocals, 4, obj.RODATA|obj.DUPOK) + + f.Config.HTML.Close() } func genValue(v *ssa.Value) { diff --git a/src/cmd/compile/internal/ssa/compile.go b/src/cmd/compile/internal/ssa/compile.go index 7ab8ddf3dc..e85fb10e00 100644 --- a/src/cmd/compile/internal/ssa/compile.go +++ b/src/cmd/compile/internal/ssa/compile.go @@ -34,13 +34,16 @@ func Compile(f *Func) { // Run all the passes printFunc(f) + f.Config.HTML.WriteFunc("start", f) checkFunc(f) for _, p := range passes { phaseName = p.name f.Logf(" pass %s begin\n", p.name) + // TODO: capture logging during this pass, add it to the HTML p.fn(f) f.Logf(" pass %s end\n", p.name) printFunc(f) + f.Config.HTML.WriteFunc("after "+phaseName, f) checkFunc(f) } diff --git a/src/cmd/compile/internal/ssa/config.go b/src/cmd/compile/internal/ssa/config.go index 8aea59d13c..ad6441117c 100644 --- a/src/cmd/compile/internal/ssa/config.go +++ b/src/cmd/compile/internal/ssa/config.go @@ -11,6 +11,7 @@ type Config struct { lowerBlock func(*Block) bool // lowering function lowerValue func(*Value, *Config) bool // lowering function fe Frontend // callbacks into compiler frontend + HTML *HTMLWriter // html writer, for debugging // TODO: more stuff. Compiler flags of interest, ... } @@ -31,12 +32,7 @@ type TypeSource interface { TypeBytePtr() Type // TODO: use unsafe.Pointer instead? } -type Frontend interface { - TypeSource - - // StringData returns a symbol pointing to the given string's contents. - StringData(string) interface{} // returns *gc.Sym - +type Logger interface { // Log logs a message from the compiler. Logf(string, ...interface{}) @@ -48,6 +44,14 @@ type Frontend interface { Unimplementedf(msg string, args ...interface{}) } +type Frontend interface { + TypeSource + Logger + + // StringData returns a symbol pointing to the given string's contents. + StringData(string) interface{} // returns *gc.Sym +} + // NewConfig returns a new configuration object for the given architecture. func NewConfig(arch string, fe Frontend) *Config { c := &Config{arch: arch, fe: fe} diff --git a/src/cmd/compile/internal/ssa/deadcode.go b/src/cmd/compile/internal/ssa/deadcode.go index 426e6865c0..109b3dd09f 100644 --- a/src/cmd/compile/internal/ssa/deadcode.go +++ b/src/cmd/compile/internal/ssa/deadcode.go @@ -4,10 +4,10 @@ package ssa -// deadcode removes dead code from f. -func deadcode(f *Func) { +// findlive returns the reachable blocks and live values in f. +func findlive(f *Func) (reachable []bool, live []bool) { // Find all reachable basic blocks. - reachable := make([]bool, f.NumBlocks()) + reachable = make([]bool, f.NumBlocks()) reachable[f.Entry.ID] = true p := []*Block{f.Entry} // stack-like worklist for len(p) > 0 { @@ -24,8 +24,8 @@ func deadcode(f *Func) { } // Find all live values - live := make([]bool, f.NumValues()) // flag to set for each live value - var q []*Value // stack-like worklist of unscanned values + live = make([]bool, f.NumValues()) // flag to set for each live value + var q []*Value // stack-like worklist of unscanned values // Starting set: all control values of reachable blocks are live. for _, b := range f.Blocks { @@ -54,6 +54,13 @@ func deadcode(f *Func) { } } + return reachable, live +} + +// deadcode removes dead code from f. +func deadcode(f *Func) { + reachable, live := findlive(f) + // Remove dead values from blocks' value list. Return dead // value ids to the allocator. for _, b := range f.Blocks { diff --git a/src/cmd/compile/internal/ssa/html.go b/src/cmd/compile/internal/ssa/html.go new file mode 100644 index 0000000000..581331a215 --- /dev/null +++ b/src/cmd/compile/internal/ssa/html.go @@ -0,0 +1,461 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +import ( + "bytes" + "fmt" + "html" + "io" + "os" +) + +type HTMLWriter struct { + Logger + *os.File +} + +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) + } + html := HTMLWriter{File: out, Logger: logger} + html.start(funcname) + return &html +} + +func (w *HTMLWriter) start(name string) { + if w == nil { + return + } + w.WriteString("") + w.WriteString(` + + + + +`) + // TODO: Add javascript click handlers for blocks + // to outline that block across all phases + w.WriteString("") + w.WriteString("

") + w.WriteString(html.EscapeString(name)) + w.WriteString("

") + w.WriteString(` +help +
+ +

+Click on a value or block to toggle highlighting of that value/block and its uses. +Values and blocks are highlighted by ID, which may vary across passes. +(TODO: Fix this.) +

+ +

+Faded out values and blocks are dead code that has not been eliminated. +

+ +

+Values printed in italics have a dependency cycle. +

+ +
+`) + w.WriteString("") + w.WriteString("") +} + +func (w *HTMLWriter) Close() { + if w == nil { + return + } + w.WriteString("") + w.WriteString("
") + w.WriteString("") + w.WriteString("") + w.File.Close() +} + +// WriteFunc writes f in a column headed by title. +func (w *HTMLWriter) WriteFunc(title string, f *Func) { + if w == nil { + return // avoid generating HTML just to discard it + } + w.WriteColumn(title, f.HTML()) + // TODO: Add visual representation of f's CFG. +} + +// WriteColumn writes raw HTML in a column headed by title. +// It is intended for pre- and post-compilation log output. +func (w *HTMLWriter) WriteColumn(title string, html string) { + if w == nil { + return + } + w.WriteString("") + w.WriteString("

" + title + "

") + w.WriteString(html) + w.WriteString("") +} + +func (w *HTMLWriter) Printf(msg string, v ...interface{}) { + if _, err := fmt.Fprintf(w.File, msg, v...); err != nil { + w.Fatalf("%v", err) + } +} + +func (w *HTMLWriter) WriteString(s string) { + if _, err := w.File.WriteString(s); err != nil { + w.Fatalf("%v", err) + } +} + +func (v *Value) HTML() string { + // TODO: Using the value ID as the class ignores the fact + // that value IDs get recycled and that some values + // are transmuted into other values. + return fmt.Sprintf("%[1]s", v.String()) +} + +func (v *Value) LongHTML() string { + // TODO: Any intra-value formatting? + // I'm wary of adding too much visual noise, + // but a little bit might be valuable. + // We already have visual noise in the form of punctuation + // maybe we could replace some of that with formatting. + s := fmt.Sprintf("", v.String()) + s += fmt.Sprintf("%s = %s", v.HTML(), v.Op.String()) + s += " <" + html.EscapeString(v.Type.String()) + ">" + if v.AuxInt != 0 { + s += fmt.Sprintf(" [%d]", v.AuxInt) + } + if v.Aux != nil { + if _, ok := v.Aux.(string); ok { + s += html.EscapeString(fmt.Sprintf(" {%q}", v.Aux)) + } else { + s += html.EscapeString(fmt.Sprintf(" {%v}", v.Aux)) + } + } + for _, a := range v.Args { + s += fmt.Sprintf(" %s", a.HTML()) + } + r := v.Block.Func.RegAlloc + if r != nil && r[v.ID] != nil { + s += " : " + r[v.ID].Name() + } + + s += "" + return s +} + +func (b *Block) HTML() string { + // TODO: Using the value ID as the class ignores the fact + // that value IDs get recycled and that some values + // are transmuted into other values. + return fmt.Sprintf("%[1]s", html.EscapeString(b.String())) +} + +func (b *Block) LongHTML() string { + // TODO: improve this for HTML? + s := b.Kind.String() + if b.Control != nil { + s += fmt.Sprintf(" %s", b.Control.HTML()) + } + if len(b.Succs) > 0 { + s += " →" // right arrow + for _, c := range b.Succs { + s += " " + c.HTML() + } + } + return s +} + +func (f *Func) HTML() string { + var buf bytes.Buffer + fmt.Fprint(&buf, "") + p := htmlFuncPrinter{w: &buf} + fprintFunc(p, f) + + // fprintFunc(&buf, f) // TODO: HTML, not text,
for line breaks, etc. + fmt.Fprint(&buf, "") + return buf.String() +} + +type htmlFuncPrinter struct { + w io.Writer +} + +func (p htmlFuncPrinter) header(f *Func) {} + +func (p htmlFuncPrinter) startBlock(b *Block, reachable bool) { + // TODO: Make blocks collapsable? + var dead string + if !reachable { + dead = "dead-block" + } + fmt.Fprintf(p.w, "") + // io.WriteString(p.w, "") +} + +func (p htmlFuncPrinter) value(v *Value, live bool) { + var dead string + if !live { + dead = "dead-value" + } + fmt.Fprintf(p.w, "
  • ", dead) + fmt.Fprint(p.w, v.LongHTML()) + io.WriteString(p.w, "
    • ") +} + +func (p htmlFuncPrinter) startDepCycle() { + fmt.Fprintln(p.w, "") +} + +func (p htmlFuncPrinter) endDepCycle() { + fmt.Fprintln(p.w, "") +} diff --git a/src/cmd/compile/internal/ssa/print.go b/src/cmd/compile/internal/ssa/print.go index 2f9db4438f..192dc83b39 100644 --- a/src/cmd/compile/internal/ssa/print.go +++ b/src/cmd/compile/internal/ssa/print.go @@ -16,33 +16,77 @@ func printFunc(f *Func) { func (f *Func) String() string { var buf bytes.Buffer - fprintFunc(&buf, f) + p := stringFuncPrinter{w: &buf} + fprintFunc(p, f) return buf.String() } -func fprintFunc(w io.Writer, f *Func) { - fmt.Fprint(w, f.Name) - fmt.Fprint(w, " ") - fmt.Fprintln(w, f.Type) +type funcPrinter interface { + header(f *Func) + startBlock(b *Block, reachable bool) + endBlock(b *Block) + value(v *Value, live bool) + startDepCycle() + endDepCycle() +} + +type stringFuncPrinter struct { + w io.Writer +} + +func (p stringFuncPrinter) header(f *Func) { + fmt.Fprint(p.w, f.Name) + fmt.Fprint(p.w, " ") + fmt.Fprintln(p.w, f.Type) +} + +func (p stringFuncPrinter) startBlock(b *Block, reachable bool) { + fmt.Fprintf(p.w, " b%d:", b.ID) + if len(b.Preds) > 0 { + io.WriteString(p.w, " <-") + for _, pred := range b.Preds { + fmt.Fprintf(p.w, " b%d", pred.ID) + } + } + if !reachable { + fmt.Fprint(p.w, " DEAD") + } + io.WriteString(p.w, "\n") +} + +func (p stringFuncPrinter) endBlock(b *Block) { + fmt.Fprintln(p.w, " "+b.LongString()) +} + +func (p stringFuncPrinter) value(v *Value, live bool) { + fmt.Fprint(p.w, " ") + fmt.Fprint(p.w, v.LongString()) + if !live { + fmt.Fprint(p.w, " DEAD") + } + fmt.Fprintln(p.w) +} + +func (p stringFuncPrinter) startDepCycle() { + fmt.Fprintln(p.w, "dependency cycle!") +} + +func (p stringFuncPrinter) endDepCycle() {} + +func fprintFunc(p funcPrinter, f *Func) { + reachable, live := findlive(f) + p.header(f) printed := make([]bool, f.NumValues()) for _, b := range f.Blocks { - fmt.Fprintf(w, " b%d:", b.ID) - if len(b.Preds) > 0 { - io.WriteString(w, " <-") - for _, pred := range b.Preds { - fmt.Fprintf(w, " b%d", pred.ID) - } - } - io.WriteString(w, "\n") + p.startBlock(b, reachable[b.ID]) if f.scheduled { // Order of Values has been decided - print in that order. for _, v := range b.Values { - fmt.Fprint(w, " ") - fmt.Fprintln(w, v.LongString()) + p.value(v, live[v.ID]) printed[v.ID] = true } - fmt.Fprintln(w, " "+b.LongString()) + p.endBlock(b) continue } @@ -52,8 +96,7 @@ func fprintFunc(w io.Writer, f *Func) { if v.Op != OpPhi { continue } - fmt.Fprint(w, " ") - fmt.Fprintln(w, v.LongString()) + p.value(v, live[v.ID]) printed[v.ID] = true n++ } @@ -73,25 +116,24 @@ func fprintFunc(w io.Writer, f *Func) { continue outer } } - fmt.Fprint(w, " ") - fmt.Fprintln(w, v.LongString()) + p.value(v, live[v.ID]) printed[v.ID] = true n++ } if m == n { - fmt.Fprintln(w, "dependency cycle!") + p.startDepCycle() for _, v := range b.Values { if printed[v.ID] { continue } - fmt.Fprint(w, " ") - fmt.Fprintln(w, v.LongString()) + p.value(v, live[v.ID]) printed[v.ID] = true n++ } + p.endDepCycle() } } - fmt.Fprintln(w, " "+b.LongString()) + p.endBlock(b) } } diff --git a/src/cmd/internal/obj/obj.go b/src/cmd/internal/obj/obj.go index af3290d3a5..6229bbb288 100644 --- a/src/cmd/internal/obj/obj.go +++ b/src/cmd/internal/obj/obj.go @@ -25,12 +25,13 @@ import ( // together, so that given (only) calls Push(10, "x.go", 1) and Pop(15), // virtual line 12 corresponds to x.go line 3. type LineHist struct { - Top *LineStack // current top of stack - Ranges []LineRange // ranges for lookup - Dir string // directory to qualify relative paths - TrimPathPrefix string // remove leading TrimPath from recorded file names - GOROOT string // current GOROOT - GOROOT_FINAL string // target GOROOT + Top *LineStack // current top of stack + Ranges []LineRange // ranges for lookup + Dir string // directory to qualify relative paths + TrimPathPrefix string // remove leading TrimPath from recorded file names + PrintFilenameOnly bool // ignore path when pretty-printing a line; internal use only + GOROOT string // current GOROOT + GOROOT_FINAL string // target GOROOT } // A LineStack is an entry in the recorded line history. @@ -221,20 +222,24 @@ func (h *LineHist) LineString(lineno int) string { return "" } - text := fmt.Sprintf("%s:%d", stk.File, stk.fileLineAt(lineno)) + filename := stk.File + if h.PrintFilenameOnly { + filename = filepath.Base(filename) + } + text := fmt.Sprintf("%s:%d", filename, stk.fileLineAt(lineno)) if stk.Directive && stk.Parent != nil { stk = stk.Parent - text += fmt.Sprintf("[%s:%d]", stk.File, stk.fileLineAt(lineno)) + text += fmt.Sprintf("[%s:%d]", filename, stk.fileLineAt(lineno)) } const showFullStack = false // was used by old C compilers if showFullStack { for stk.Parent != nil { lineno = stk.Lineno - 1 stk = stk.Parent - text += fmt.Sprintf(" %s:%d", stk.File, stk.fileLineAt(lineno)) + text += fmt.Sprintf(" %s:%d", filename, stk.fileLineAt(lineno)) if stk.Directive && stk.Parent != nil { stk = stk.Parent - text += fmt.Sprintf("[%s:%d]", stk.File, stk.fileLineAt(lineno)) + text += fmt.Sprintf("[%s:%d]", filename, stk.fileLineAt(lineno)) } } }