cmd/compile: adjust GOSSAFUNC html dumping to be more ABI-aware

Uses ,ABI instead of <ABI> because of problems with shell escaping
and windows file names, however if someone goes to all the trouble
of escaping the linker syntax and uses that instead, that works too.

Examples:
```
GOSSAFUNC=runtime.exitsyscall go build main.go
\# runtime
dumped SSA for exitsyscall,0 to ../../src/loopvar/ssa.html
dumped SSA for exitsyscall,1 to ../../src/loopvar/ssa.html

GOSSADIR=`pwd` GOSSAFUNC=runtime.exitsyscall go build main.go
\# runtime
dumped SSA for exitsyscall,0 to ../../src/loopvar/runtime.exitsyscall,0.html
dumped SSA for exitsyscall,1 to ../../src/loopvar/runtime.exitsyscall,1.html

GOSSAFUNC=runtime.exitsyscall,0 go build main.go
\# runtime
dumped SSA for exitsyscall,0 to ../../src/loopvar/ssa.html

GOSSAFUNC=runtime.exitsyscall\<1\> go build main.go
\# runtime
dumped SSA for exitsyscall,1 to ../../src/loopvar/ssa.html
```

Change-Id: Ia1138b61c797d0de49dbfae702dc306b9650a7f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/532475
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: David Chase <drchase@google.com>

src/cmd/compile/internal/abi/abiutils.go

@@ -8,6 +8,7 @@ import (
 	"cmd/compile/internal/base"
 	"cmd/compile/internal/ir"
 	"cmd/compile/internal/types"
+	"cmd/internal/obj"
 	"cmd/internal/src"
 	"fmt"
 	"math"
@@ -261,12 +262,13 @@ type ABIConfig struct {
 	// Do we need anything more than this?
 	offsetForLocals int64 // e.g., obj.(*Link).Arch.FixedFrameSize -- extra linkage information on some architectures.
 	regAmounts      RegAmounts
+	which           obj.ABI
 }
 
 // NewABIConfig returns a new ABI configuration for an architecture with
 // iRegsCount integer/pointer registers and fRegsCount floating point registers.
-func NewABIConfig(iRegsCount, fRegsCount int, offsetForLocals int64) *ABIConfig {
+func NewABIConfig(iRegsCount, fRegsCount int, offsetForLocals int64, which uint8) *ABIConfig {
-	return &ABIConfig{offsetForLocals: offsetForLocals, regAmounts: RegAmounts{iRegsCount, fRegsCount}}
+	return &ABIConfig{offsetForLocals: offsetForLocals, regAmounts: RegAmounts{iRegsCount, fRegsCount}, which: obj.ABI(which)}
 }
 
 // Copy returns config.
@@ -276,6 +278,11 @@ func (config *ABIConfig) Copy() *ABIConfig {
 	return config
 }
 
+// Which returns the ABI number
+func (config *ABIConfig) Which() obj.ABI {
+	return config.which
+}
+
 // LocalsOffset returns the architecture-dependent offset from SP for args and results.
 // In theory this is only used for debugging; it ought to already be incorporated into
 // results from the ABI-related methods

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

@@ -361,8 +361,8 @@ func NewConfig(arch string, types Types, ctxt *obj.Link, optimize, softfloat boo
 		c.floatParamRegs = nil // no FP registers in softfloat mode
 	}
 
-	c.ABI0 = abi.NewABIConfig(0, 0, ctxt.Arch.FixedFrameSize)
+	c.ABI0 = abi.NewABIConfig(0, 0, ctxt.Arch.FixedFrameSize, 0)
-	c.ABI1 = abi.NewABIConfig(len(c.intParamRegs), len(c.floatParamRegs), ctxt.Arch.FixedFrameSize)
+	c.ABI1 = abi.NewABIConfig(len(c.intParamRegs), len(c.floatParamRegs), ctxt.Arch.FixedFrameSize, 1)
 
 	// On Plan 9, floating point operations are not allowed in note handler.
 	if buildcfg.GOOS == "plan9" {

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

@@ -10,6 +10,7 @@ import (
 	"cmd/compile/internal/ir"
 	"cmd/compile/internal/typecheck"
 	"cmd/compile/internal/types"
+	"cmd/internal/obj"
 	"cmd/internal/src"
 	"fmt"
 	"math"
@@ -109,6 +110,21 @@ func (f *Func) NumValues() int {
 	return f.vid.num()
 }
 
+// NameABI returns the function name followed by comma and the ABI number.
+// This is intended for use with GOSSAFUNC and HTML dumps, and differs from
+// the linker's "<1>" convention because "<" and ">" require shell quoting
+// and are not legal file names (for use with GOSSADIR) on Windows.
+func (f *Func) NameABI() string {
+	return FuncNameABI(f.Name, f.ABISelf.Which())
+}
+
+// FuncNameABI returns n followed by a comma and the value of a.
+// This is a separate function to allow a single point encoding
+// of the format, which is used in places where there's not a Func yet.
+func FuncNameABI(n string, a obj.ABI) string {
+	return fmt.Sprintf("%s,%d", n, a)
+}
+
 // newSparseSet returns a sparse set that can store at least up to n integers.
 func (f *Func) newSparseSet(n int) *sparseSet {
 	return f.Cache.allocSparseSet(n)

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

@@ -741,7 +741,7 @@ function toggleDarkMode() {
 </head>`)
 	w.WriteString("<body>")
 	w.WriteString("<h1>")
-	w.WriteString(html.EscapeString(w.Func.Name))
+	w.WriteString(html.EscapeString(w.Func.NameABI()))
 	w.WriteString("</h1>")
 	w.WriteString(`
 <a href="#" onclick="toggle_visibility('help');return false;" id="helplink">help</a>
@@ -784,7 +784,7 @@ func (w *HTMLWriter) Close() {
 	io.WriteString(w.w, "</body>")
 	io.WriteString(w.w, "</html>")
 	w.w.Close()
-	fmt.Printf("dumped SSA to %v\n", w.path)
+	fmt.Printf("dumped SSA for %s to %v\n", w.Func.NameABI(), w.path)
 }
 
 // WritePhase writes f in a column headed by title.

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

@@ -314,12 +314,29 @@ func (s *state) emitOpenDeferInfo() {
 // worker indicates which of the backend workers is doing the processing.
 func buildssa(fn *ir.Func, worker int) *ssa.Func {
 	name := ir.FuncName(fn)
+
+	abiSelf := abiForFunc(fn, ssaConfig.ABI0, ssaConfig.ABI1)
+
 	printssa := false
-	if ssaDump != "" { // match either a simple name e.g. "(*Reader).Reset", package.name e.g. "compress/gzip.(*Reader).Reset", or subpackage name "gzip.(*Reader).Reset"
+	// match either a simple name e.g. "(*Reader).Reset", package.name e.g. "compress/gzip.(*Reader).Reset", or subpackage name "gzip.(*Reader).Reset"
-		pkgDotName := base.Ctxt.Pkgpath + "." + name
+	// optionally allows an ABI suffix specification in the GOSSAHASH, e.g. "(*Reader).Reset<0>" etc
-		printssa = name == ssaDump ||
+	if strings.Contains(ssaDump, name) { // in all the cases the function name is entirely contained within the GOSSAFUNC string.
-			strings.HasSuffix(pkgDotName, ssaDump) && (pkgDotName == ssaDump || strings.HasSuffix(pkgDotName, "/"+ssaDump))
+		nameOptABI := name
+		if strings.Contains(ssaDump, ",") { // ABI specification
+			nameOptABI = ssa.FuncNameABI(name, abiSelf.Which())
+		} else if strings.HasSuffix(ssaDump, ">") { // if they use the linker syntax instead....
+			l := len(ssaDump)
+			if l >= 3 && ssaDump[l-3] == '<' {
+				nameOptABI = ssa.FuncNameABI(name, abiSelf.Which())
+				ssaDump = ssaDump[:l-3] + "," + ssaDump[l-2:l-1]
+			}
+		}
+		pkgDotName := base.Ctxt.Pkgpath + "." + nameOptABI
+		printssa = nameOptABI == ssaDump || // "(*Reader).Reset"
+			pkgDotName == ssaDump || // "compress/gzip.(*Reader).Reset"
+			strings.HasSuffix(pkgDotName, ssaDump) && strings.HasSuffix(pkgDotName, "/"+ssaDump) // "gzip.(*Reader).Reset"
 	}
+
 	var astBuf *bytes.Buffer
 	if printssa {
 		astBuf = &bytes.Buffer{}
@@ -366,10 +383,10 @@ func buildssa(fn *ir.Func, worker int) *ssa.Func {
 	if fn.Pragma&ir.Nosplit != 0 {
 		s.f.NoSplit = true
 	}
-	s.f.ABI0 = ssaConfig.ABI0.Copy() // Make a copy to avoid racy map operations in type-register-width cache.
+	s.f.ABI0 = ssaConfig.ABI0
-	s.f.ABI1 = ssaConfig.ABI1.Copy()
+	s.f.ABI1 = ssaConfig.ABI1
-	s.f.ABIDefault = abiForFunc(nil, s.f.ABI0, s.f.ABI1)
+	s.f.ABIDefault = abiForFunc(nil, ssaConfig.ABI0, ssaConfig.ABI1)
-	s.f.ABISelf = abiForFunc(fn, s.f.ABI0, s.f.ABI1)
+	s.f.ABISelf = abiSelf
 
 	s.panics = map[funcLine]*ssa.Block{}
 	s.softFloat = s.config.SoftFloat
@@ -381,7 +398,7 @@ func buildssa(fn *ir.Func, worker int) *ssa.Func {
 	if printssa {
 		ssaDF := ssaDumpFile
 		if ssaDir != "" {
-			ssaDF = filepath.Join(ssaDir, base.Ctxt.Pkgpath+"."+name+".html")
+			ssaDF = filepath.Join(ssaDir, base.Ctxt.Pkgpath+"."+s.f.NameABI()+".html")
 			ssaD := filepath.Dir(ssaDF)
 			os.MkdirAll(ssaD, 0755)
 		}

src/cmd/compile/internal/test/abiutils_test.go

@@ -22,7 +22,7 @@ import (
 // AMD64 registers available:
 // - integer: RAX, RBX, RCX, RDI, RSI, R8, R9, r10, R11
 // - floating point: X0 - X14
-var configAMD64 = abi.NewABIConfig(9, 15, 0)
+var configAMD64 = abi.NewABIConfig(9, 15, 0, 1)
 
 func TestMain(m *testing.M) {
 	ssagen.Arch.LinkArch = &x86.Linkamd64