From ddccd95d07178ab01ee7d281b3544997d9819260 Mon Sep 17 00:00:00 2001 From: Yury Smolsky Date: Tue, 16 Oct 2018 13:03:35 +0300 Subject: [PATCH] cmd/compile: add control flow graphs to ssa.html This CL adds CFGs to ssa.html. It execs dot to generate SVG, which then gets inlined into the html. Some standard naming and javascript hacks enable integration with the rest of ssa.html. Clicking on blocks highlights the relevant part of the CFG, and vice versa. Sample output and screenshots can be seen in #28177. CFGs can be turned on with the suffix mask: :* - dump CFG for every phase :lower - just the lower phase :lower-layout - lower through layout :w,x-y - phases w and x through y Calling dot after every pass is noticeably slow, instead use the range of phases. Dead blocks are not displayed on CFG. User can zoom and pan individual CFG when the automatic adjustment has failed. Dot-related errors are reported without bringing down the process. Fixes #28177 Change-Id: Id52c42d86c4559ca737288aa10561b67a119c63d Reviewed-on: https://go-review.googlesource.com/c/142517 Run-TryBot: Yury Smolsky Reviewed-by: David Chase --- src/cmd/compile/internal/gc/main.go | 13 +- src/cmd/compile/internal/gc/ssa.go | 3 +- src/cmd/compile/internal/ssa/func.go | 1 + src/cmd/compile/internal/ssa/html.go | 344 ++++++++++++++++++++++++- src/cmd/compile/internal/ssa/layout.go | 2 + 5 files changed, 348 insertions(+), 15 deletions(-) diff --git a/src/cmd/compile/internal/gc/main.go b/src/cmd/compile/internal/gc/main.go index b843ebf4370476..9dd28e38c3bf18 100644 --- a/src/cmd/compile/internal/gc/main.go +++ b/src/cmd/compile/internal/gc/main.go @@ -438,9 +438,16 @@ func Main(archInit func(*Arch)) { } ssaDump = os.Getenv("GOSSAFUNC") - if strings.HasSuffix(ssaDump, "+") { - ssaDump = ssaDump[:len(ssaDump)-1] - ssaDumpStdout = true + if ssaDump != "" { + if strings.HasSuffix(ssaDump, "+") { + ssaDump = ssaDump[:len(ssaDump)-1] + ssaDumpStdout = true + } + spl := strings.Split(ssaDump, ":") + if len(spl) > 1 { + ssaDump = spl[0] + ssaDumpCFG = spl[1] + } } trackScopes = flagDWARF diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go index 7a4152a9e6d489..27af607d6f0e50 100644 --- a/src/cmd/compile/internal/gc/ssa.go +++ b/src/cmd/compile/internal/gc/ssa.go @@ -26,6 +26,7 @@ var ssaCaches []ssa.Cache var ssaDump string // early copy of $GOSSAFUNC; the func name to dump output for var ssaDumpStdout bool // whether to dump to stdout +var ssaDumpCFG string // generate CFGs for these phases const ssaDumpFile = "ssa.html" // ssaDumpInlined holds all inlined functions when ssaDump contains a function name. @@ -155,7 +156,7 @@ func buildssa(fn *Node, worker int) *ssa.Func { s.softFloat = s.config.SoftFloat if printssa { - s.f.HTMLWriter = ssa.NewHTMLWriter(ssaDumpFile, s.f.Frontend(), name) + s.f.HTMLWriter = ssa.NewHTMLWriter(ssaDumpFile, s.f.Frontend(), name, ssaDumpCFG) // TODO: generate and print a mapping from nodes to values and blocks dumpSourcesColumn(s.f.HTMLWriter, fn) s.f.HTMLWriter.WriteAST("AST", astBuf) diff --git a/src/cmd/compile/internal/ssa/func.go b/src/cmd/compile/internal/ssa/func.go index d73d39ce288f51..7e7e2042d9da54 100644 --- a/src/cmd/compile/internal/ssa/func.go +++ b/src/cmd/compile/internal/ssa/func.go @@ -43,6 +43,7 @@ type Func struct { PrintOrHtmlSSA bool // true if GOSSAFUNC matches, true even if fe.Log() (spew phase results to stdout) is false. scheduled bool // Values in Blocks are in final order + laidout bool // Blocks are ordered NoSplit bool // true if function is marked as nosplit. Used by schedule check pass. // when register allocation is done, maps value ids to locations diff --git a/src/cmd/compile/internal/ssa/html.go b/src/cmd/compile/internal/ssa/html.go index d76d7c7b334650..3ea83f90a271cb 100644 --- a/src/cmd/compile/internal/ssa/html.go +++ b/src/cmd/compile/internal/ssa/html.go @@ -11,6 +11,7 @@ import ( "html" "io" "os" + "os/exec" "path/filepath" "strconv" "strings" @@ -20,9 +21,10 @@ type HTMLWriter struct { Logger w io.WriteCloser path string + dot *dotWriter } -func NewHTMLWriter(path string, logger Logger, funcname string) *HTMLWriter { +func NewHTMLWriter(path string, logger Logger, funcname, cfgMask string) *HTMLWriter { out, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644) if err != nil { logger.Fatalf(src.NoXPos, "%v", err) @@ -32,6 +34,7 @@ func NewHTMLWriter(path string, logger Logger, funcname string) *HTMLWriter { logger.Fatalf(src.NoXPos, "%v", err) } html := HTMLWriter{w: out, Logger: logger, path: filepath.Join(pwd, path)} + html.dot = newDotWriter(cfgMask) html.start(funcname) return &html } @@ -211,6 +214,25 @@ dd.ssa-prog { color: gray; } +.zoom { + position: absolute; + float: left; + white-space: nowrap; + background-color: #eee; +} + +.zoom a:link, .zoom a:visited { + text-decoration: none; + color: blue; + font-size: 16px; + padding: 4px 2px; +} + +svg { + cursor: default; + outline: 1px solid #eee; +} + .highlight-aquamarine { background-color: aquamarine; } .highlight-coral { background-color: coral; } .highlight-lightpink { background-color: lightpink; } @@ -236,6 +258,18 @@ dd.ssa-prog { .outline-maroon { outline: maroon solid 2px; } .outline-black { outline: black solid 2px; } +ellipse.outline-blue { stroke-width: 2px; stroke: blue; } +ellipse.outline-red { stroke-width: 2px; stroke: red; } +ellipse.outline-blueviolet { stroke-width: 2px; stroke: blueviolet; } +ellipse.outline-darkolivegreen { stroke-width: 2px; stroke: darkolivegreen; } +ellipse.outline-fuchsia { stroke-width: 2px; stroke: fuchsia; } +ellipse.outline-sienna { stroke-width: 2px; stroke: sienna; } +ellipse.outline-gold { stroke-width: 2px; stroke: gold; } +ellipse.outline-orangered { stroke-width: 2px; stroke: orangered; } +ellipse.outline-teal { stroke-width: 2px; stroke: teal; } +ellipse.outline-maroon { stroke-width: 2px; stroke: maroon; } +ellipse.outline-black { stroke-width: 2px; stroke: black; } + + +// TODO: scale the graph with the viewBox attribute. +function graphReduce(id) { + var node = document.getElementById(id); + if (node) { + node.width.baseVal.value *= 0.9; + node.height.baseVal.value *= 0.9; + } + return false; +} + +function graphEnlarge(id) { + var node = document.getElementById(id); + if (node) { + node.width.baseVal.value *= 1.1; + node.height.baseVal.value *= 1.1; + } + return false; +} + +function makeDraggable(event) { + var svg = event.target; + if (window.PointerEvent) { + svg.addEventListener('pointerdown', startDrag); + svg.addEventListener('pointermove', drag); + svg.addEventListener('pointerup', endDrag); + svg.addEventListener('pointerleave', endDrag); + } else { + svg.addEventListener('mousedown', startDrag); + svg.addEventListener('mousemove', drag); + svg.addEventListener('mouseup', endDrag); + svg.addEventListener('mouseleave', endDrag); + } + + var point = svg.createSVGPoint(); + var isPointerDown = false; + var pointerOrigin; + var viewBox = svg.viewBox.baseVal; + + function getPointFromEvent (event) { + point.x = event.clientX; + point.y = event.clientY; + + // We get the current transformation matrix of the SVG and we inverse it + var invertedSVGMatrix = svg.getScreenCTM().inverse(); + return point.matrixTransform(invertedSVGMatrix); + } + + function startDrag(event) { + isPointerDown = true; + pointerOrigin = getPointFromEvent(event); + } + + function drag(event) { + if (!isPointerDown) { + return; + } + event.preventDefault(); + + var pointerPosition = getPointFromEvent(event); + viewBox.x -= (pointerPosition.x - pointerOrigin.x); + viewBox.y -= (pointerPosition.y - pointerOrigin.y); + } + + function endDrag(event) { + isPointerDown = false; + } +} `) w.WriteString("") @@ -431,7 +564,7 @@ function toggle_visibility(id) { w.WriteString(html.EscapeString(name)) w.WriteString("") w.WriteString(` -help +help

@@ -449,6 +582,11 @@ Faded out values and blocks are dead code that has not been eliminated. Values printed in italics have a dependency cycle.

+

+CFG: Dashed edge is for unlikely branches. Blue color is for backward edges. +Edge with a dot means that this edge follows the order in which blocks were laidout. +

+
`) w.WriteString("") @@ -473,8 +611,8 @@ func (w *HTMLWriter) WriteFunc(phase, title string, f *Func) { if w == nil { return // avoid generating HTML just to discard it } - w.WriteColumn(phase, title, "", f.HTML()) - // TODO: Add visual representation of f's CFG. + //w.WriteColumn(phase, title, "", f.HTML()) + w.WriteColumn(phase, title, "", f.HTML(phase, w.dot)) } // FuncLines contains source code for a function to be displayed @@ -704,17 +842,142 @@ func (b *Block) LongHTML() string { return s } -func (f *Func) HTML() string { - var buf bytes.Buffer - fmt.Fprint(&buf, "") - p := htmlFuncPrinter{w: &buf} +func (f *Func) HTML(phase string, dot *dotWriter) string { + buf := new(bytes.Buffer) + if dot != nil { + dot.writeFuncSVG(buf, phase, f) + } + fmt.Fprint(buf, "") + p := htmlFuncPrinter{w: buf} fprintFunc(p, f) // fprintFunc(&buf, f) // TODO: HTML, not text,
for line breaks, etc. - fmt.Fprint(&buf, "") + fmt.Fprint(buf, "") return buf.String() } +func (d *dotWriter) writeFuncSVG(w io.Writer, phase string, f *Func) { + if d.broken { + return + } + if _, ok := d.phases[phase]; !ok { + return + } + cmd := exec.Command(d.path, "-Tsvg") + pipe, err := cmd.StdinPipe() + if err != nil { + d.broken = true + fmt.Println(err) + return + } + buf := new(bytes.Buffer) + cmd.Stdout = buf + bufErr := new(bytes.Buffer) + cmd.Stderr = bufErr + err = cmd.Start() + if err != nil { + d.broken = true + fmt.Println(err) + return + } + fmt.Fprint(pipe, `digraph "" { margin=0; size="4,40"; ranksep=.2; `) + id := strings.Replace(phase, " ", "-", -1) + fmt.Fprintf(pipe, `id="g_graph_%s";`, id) + fmt.Fprintf(pipe, `node [style=filled,fillcolor=white,fontsize=16,fontname="Menlo,Times,serif",margin="0.01,0.03"];`) + fmt.Fprintf(pipe, `edge [fontsize=16,fontname="Menlo,Times,serif"];`) + for i, b := range f.Blocks { + if b.Kind == BlockInvalid { + continue + } + layout := "" + if f.laidout { + layout = fmt.Sprintf(" #%d", i) + } + fmt.Fprintf(pipe, `%v [label="%v%s\n%v",id="graph_node_%v_%v",tooltip="%v"];`, b, b, layout, b.Kind, id, b, b.LongString()) + } + indexOf := make([]int, f.NumBlocks()) + for i, b := range f.Blocks { + indexOf[b.ID] = i + } + layoutDrawn := make([]bool, f.NumBlocks()) + + ponums := make([]int32, f.NumBlocks()) + _ = postorderWithNumbering(f, ponums) + isBackEdge := func(from, to ID) bool { + return ponums[from] <= ponums[to] + } + + for _, b := range f.Blocks { + for i, s := range b.Succs { + style := "solid" + color := "black" + arrow := "vee" + if b.unlikelyIndex() == i { + style = "dashed" + } + if f.laidout && indexOf[s.b.ID] == indexOf[b.ID]+1 { + // Red color means ordered edge. It overrides other colors. + arrow = "dotvee" + layoutDrawn[s.b.ID] = true + } else if isBackEdge(b.ID, s.b.ID) { + color = "blue" + } + fmt.Fprintf(pipe, `%v -> %v [label=" %d ",style="%s",color="%s",arrowhead="%s"];`, b, s.b, i, style, color, arrow) + } + } + if f.laidout { + fmt.Fprintln(pipe, `edge[constraint=false,color=gray,style=solid,arrowhead=dot];`) + colors := [...]string{"#eea24f", "#f38385", "#f4d164", "#ca89fc", "gray"} + ci := 0 + for i := 1; i < len(f.Blocks); i++ { + if layoutDrawn[f.Blocks[i].ID] { + continue + } + fmt.Fprintf(pipe, `%s -> %s [color="%s"];`, f.Blocks[i-1], f.Blocks[i], colors[ci]) + ci = (ci + 1) % len(colors) + } + } + fmt.Fprint(pipe, "}") + pipe.Close() + err = cmd.Wait() + if err != nil { + d.broken = true + fmt.Printf("dot: %s\n%v\n", err, bufErr.String()) + return + } + + svgID := "svg_graph_" + id + fmt.Fprintf(w, `
`, svgID, svgID) + // For now, an awful hack: edit the html as it passes through + // our fingers, finding '") io.WriteString(p.w, "") - // io.WriteString(p.w, "") } func (p htmlFuncPrinter) value(v *Value, live bool) { @@ -780,3 +1042,63 @@ func (p htmlFuncPrinter) named(n LocalSlot, vals []*Value) { } fmt.Fprintf(p.w, "") } + +type dotWriter struct { + path string + broken bool + phases map[string]bool // keys specify phases with CFGs +} + +// newDotWriter returns non-nil value when mask is valid. +// dotWriter will generate SVGs only for the phases specifed in the mask. +// mask can contain following patterns and combinations of them: +// * - all of them; +// x-y - x through y, inclusive; +// x,y - x and y, but not the passes between. +func newDotWriter(mask string) *dotWriter { + if mask == "" { + return nil + } + // User can specify phase name with _ instead of spaces. + mask = strings.Replace(mask, "_", " ", -1) + ph := make(map[string]bool) + ranges := strings.Split(mask, ",") + for _, r := range ranges { + spl := strings.Split(r, "-") + if len(spl) > 2 { + fmt.Printf("range is not valid: %v\n", mask) + return nil + } + var first, last int + if mask == "*" { + first = 0 + last = len(passes) - 1 + } else { + first = passIdxByName(spl[0]) + last = passIdxByName(spl[len(spl)-1]) + } + if first < 0 || last < 0 || first > last { + fmt.Printf("range is not valid: %v\n", r) + return nil + } + for p := first; p <= last; p++ { + ph[passes[p].name] = true + } + } + + path, err := exec.LookPath("dot") + if err != nil { + fmt.Println(err) + return nil + } + return &dotWriter{path: path, phases: ph} +} + +func passIdxByName(name string) int { + for i, p := range passes { + if p.name == name { + return i + } + } + return -1 +} diff --git a/src/cmd/compile/internal/ssa/layout.go b/src/cmd/compile/internal/ssa/layout.go index 78d5dc77fed23e..338cd91c47feba 100644 --- a/src/cmd/compile/internal/ssa/layout.go +++ b/src/cmd/compile/internal/ssa/layout.go @@ -143,5 +143,7 @@ blockloop: } } } + f.laidout = true return order + //f.Blocks = order }