cmd/compile: ppc64le working, not optimized enough

This time with the cherry-pick from the proper patch of
the old CL.

Stack size increased.
Corrected NaN-comparison glitches.
Marked g register as clobbered by calls.
Fixed shared libraries.

live_ssa.go still disabled because of differences.
Presumably turning on more optimization will fix
both the stack size and the live_ssa.go glitches.

Enhanced debugging output for shared libs test.

Rebased onto master.

Updates #16010.

Change-Id: I40864faf1ef32c118fb141b7ef8e854498e6b2c4
Reviewed-on: https://go-review.googlesource.com/27159
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

misc/cgo/testshared/shared_test.go

@@ -97,6 +97,9 @@ func testMain(m *testing.M) (int, error) {
 	if gorootInstallDir == "" {
 		return 0, errors.New("could not create temporary directory after 10000 tries")
 	}
+	if testing.Verbose() {
+		fmt.Printf("+ mkdir -p %s\n", gorootInstallDir)
+	}
 	defer os.RemoveAll(gorootInstallDir)
 
 	// Some tests need to edit the source in GOPATH, so copy this directory to a
@@ -105,6 +108,9 @@ func testMain(m *testing.M) (int, error) {
 	if err != nil {
 		return 0, fmt.Errorf("TempDir failed: %v", err)
 	}
+	if testing.Verbose() {
+		fmt.Printf("+ mkdir -p %s\n", scratchDir)
+	}
 	defer os.RemoveAll(scratchDir)
 	err = filepath.Walk(".", func(path string, info os.FileInfo, err error) error {
 		scratchPath := filepath.Join(scratchDir, path)
@@ -112,12 +118,18 @@ func testMain(m *testing.M) (int, error) {
 			if path == "." {
 				return nil
 			}
+			if testing.Verbose() {
+				fmt.Printf("+ mkdir -p %s\n", scratchPath)
+			}
 			return os.Mkdir(scratchPath, info.Mode())
 		} else {
 			fromBytes, err := ioutil.ReadFile(path)
 			if err != nil {
 				return err
 			}
+			if testing.Verbose() {
+				fmt.Printf("+ cp %s %s\n", path, scratchPath)
+			}
 			return ioutil.WriteFile(scratchPath, fromBytes, info.Mode())
 		}
 	})
@@ -125,7 +137,13 @@ func testMain(m *testing.M) (int, error) {
 		return 0, fmt.Errorf("walk failed: %v", err)
 	}
 	os.Setenv("GOPATH", scratchDir)
+	if testing.Verbose() {
+		fmt.Printf("+ export GOPATH=%s\n", scratchDir)
+	}
 	myContext.GOPATH = scratchDir
+	if testing.Verbose() {
+		fmt.Printf("+ cd %s\n", scratchDir)
+	}
 	os.Chdir(scratchDir)
 
 	// All tests depend on runtime being built into a shared library. Because

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

@@ -40,7 +40,7 @@ func shouldssa(fn *Node) bool {
 		if os.Getenv("SSATEST") == "" {
 			return false
 		}
-	case "amd64", "amd64p32", "arm", "386", "arm64":
+	case "amd64", "amd64p32", "arm", "386", "arm64", "ppc64le":
 		// Generally available.
 	}
 	if !ssaEnabled {

src/cmd/compile/internal/ppc64/ssa.go

@@ -747,9 +747,27 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 			// This is different from obj.ANOP, which is a virtual no-op
 			// that doesn't make it into the instruction stream.
 			// PPC64 is unusual because TWO nops are required
-			// (see gc/cgen.go, gc/plive.go)
-			ginsnop()
+			// (see gc/cgen.go, gc/plive.go -- copy of comment below)
+			//
+			// On ppc64, when compiling Go into position
+			// independent code on ppc64le we insert an
+			// instruction to reload the TOC pointer from the
+			// stack as well. See the long comment near
+			// jmpdefer in runtime/asm_ppc64.s for why.
+			// If the MOVD is not needed, insert a hardware NOP
+			// so that the same number of instructions are used
+			// on ppc64 in both shared and non-shared modes.
 			ginsnop()
+			if gc.Ctxt.Flag_shared {
+				p := gc.Prog(ppc64.AMOVD)
+				p.From.Type = obj.TYPE_MEM
+				p.From.Offset = 24
+				p.From.Reg = ppc64.REGSP
+				p.To.Type = obj.TYPE_REG
+				p.To.Reg = ppc64.REG_R2
+			} else {
+				ginsnop()
+			}
 		}
 		p := gc.Prog(obj.ACALL)
 		p.To.Type = obj.TYPE_MEM
@@ -758,13 +776,48 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		if gc.Maxarg < v.AuxInt {
 			gc.Maxarg = v.AuxInt
 		}
-	case ssa.OpPPC64CALLclosure:
-		p := gc.Prog(obj.ACALL)
-		p.To.Type = obj.TYPE_MEM
-		p.To.Reg = gc.SSARegNum(v.Args[0])
+
+	case ssa.OpPPC64CALLclosure, ssa.OpPPC64CALLinter:
+		p := gc.Prog(ppc64.AMOVD)
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = gc.SSARegNum(v.Args[0])
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = ppc64.REG_CTR
+
+		if gc.Ctxt.Flag_shared && p.From.Reg != ppc64.REG_R12 {
+			// Make sure function pointer is in R12 as well when
+			// compiling Go into PIC.
+			// TODO(mwhudson): it would obviously be better to
+			// change the register allocation to put the value in
+			// R12 already, but I don't know how to do that.
+			// TODO: We have the technology now to implement TODO above.
+			q := gc.Prog(ppc64.AMOVD)
+			q.From = p.From
+			q.To.Type = obj.TYPE_REG
+			q.To.Reg = ppc64.REG_R12
+		}
+
+		pp := gc.Prog(obj.ACALL)
+		pp.To.Type = obj.TYPE_REG
+		pp.To.Reg = ppc64.REG_CTR
+
+		if gc.Ctxt.Flag_shared {
+			// When compiling Go into PIC, the function we just
+			// called via pointer might have been implemented in
+			// a separate module and so overwritten the TOC
+			// pointer in R2; reload it.
+			q := gc.Prog(ppc64.AMOVD)
+			q.From.Type = obj.TYPE_MEM
+			q.From.Offset = 24
+			q.From.Reg = ppc64.REGSP
+			q.To.Type = obj.TYPE_REG
+			q.To.Reg = ppc64.REG_R2
+		}
+
 		if gc.Maxarg < v.AuxInt {
 			gc.Maxarg = v.AuxInt
 		}
+
 	case ssa.OpPPC64CALLdefer:
 		p := gc.Prog(obj.ACALL)
 		p.To.Type = obj.TYPE_MEM
@@ -781,14 +834,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		if gc.Maxarg < v.AuxInt {
 			gc.Maxarg = v.AuxInt
 		}
-	case ssa.OpPPC64CALLinter:
-		p := gc.Prog(obj.ACALL)
-		p.To.Type = obj.TYPE_MEM
-		p.To.Reg = gc.SSARegNum(v.Args[0])
-		if gc.Maxarg < v.AuxInt {
-			gc.Maxarg = v.AuxInt
-		}
-
 	case ssa.OpVarDef:
 		gc.Gvardef(v.Aux.(*gc.Node))
 	case ssa.OpVarKill:
@@ -902,7 +947,7 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 
 var blockJump = [...]struct {
 	asm, invasm     obj.As
-	asmeq, invasmeq bool
+	asmeq, invasmun bool
 }{
 	ssa.BlockPPC64EQ: {ppc64.ABEQ, ppc64.ABNE, false, false},
 	ssa.BlockPPC64NE: {ppc64.ABNE, ppc64.ABEQ, false, false},
@@ -913,10 +958,10 @@ var blockJump = [...]struct {
 	ssa.BlockPPC64GT: {ppc64.ABGT, ppc64.ABLE, false, false},
 
 	// TODO: need to work FP comparisons into block jumps
-	ssa.BlockPPC64FLT: {ppc64.ABLT, ppc64.ABGT, false, true},
-	ssa.BlockPPC64FGE: {ppc64.ABGT, ppc64.ABLT, true, false},
-	ssa.BlockPPC64FLE: {ppc64.ABLT, ppc64.ABGT, true, false},
-	ssa.BlockPPC64FGT: {ppc64.ABGT, ppc64.ABLT, false, true},
+	ssa.BlockPPC64FLT: {ppc64.ABLT, ppc64.ABGE, false, false},
+	ssa.BlockPPC64FGE: {ppc64.ABGT, ppc64.ABLT, true, true}, // GE = GT or EQ; !GE = LT or UN
+	ssa.BlockPPC64FLE: {ppc64.ABLT, ppc64.ABGT, true, true}, // LE = LT or EQ; !LE = GT or UN
+	ssa.BlockPPC64FGT: {ppc64.ABGT, ppc64.ABLE, false, false},
 }
 
 func ssaGenBlock(s *gc.SSAGenState, b, next *ssa.Block) {
@@ -973,9 +1018,9 @@ func ssaGenBlock(s *gc.SSAGenState, b, next *ssa.Block) {
 			likely *= -1
 			p.To.Type = obj.TYPE_BRANCH
 			s.Branches = append(s.Branches, gc.Branch{P: p, B: b.Succs[1].Block()})
-			if jmp.invasmeq {
-				// TODO: The second branch is probably predict-not-taken since it is for FP equality
-				q := gc.Prog(ppc64.ABEQ)
+			if jmp.invasmun {
+				// TODO: The second branch is probably predict-not-taken since it is for FP unordered
+				q := gc.Prog(ppc64.ABVS)
 				q.To.Type = obj.TYPE_BRANCH
 				s.Branches = append(s.Branches, gc.Branch{P: q, B: b.Succs[1].Block()})
 			}

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

@@ -254,6 +254,7 @@ func (c *Config) Set387(b bool) {
 
 func (c *Config) Frontend() Frontend      { return c.fe }
 func (c *Config) SparsePhiCutoff() uint64 { return c.sparsePhiCutoff }
+func (c *Config) Ctxt() *obj.Link         { return c.ctxt }
 
 // NewFunc returns a new, empty function object.
 // Caller must call f.Free() before calling NewFunc again.

src/cmd/compile/internal/ssa/gen/PPC64.rules

@@ -380,10 +380,11 @@
 (GreaterThan (InvertFlags x)) -> (LessThan x)
 (LessEqual (InvertFlags x)) -> (GreaterEqual x)
 (GreaterEqual (InvertFlags x)) -> (LessEqual x)
-(FLessThan (InvertFlags x)) -> (FGreaterThan x)
-(FGreaterThan (InvertFlags x)) -> (FLessThan x)
-(FLessEqual (InvertFlags x)) -> (FGreaterEqual x)
-(FGreaterEqual (InvertFlags x)) -> (FLessEqual x)
+
+// (FLessThan (InvertFlags x)) -> (FGreaterThan x)
+// (FGreaterThan (InvertFlags x)) -> (FLessThan x)
+// (FLessEqual (InvertFlags x)) -> (FGreaterEqual x)
+// (FGreaterEqual (InvertFlags x)) -> (FLessEqual x)
 
 
 // Lowering loads

src/cmd/compile/internal/ssa/gen/PPC64Ops.go

@@ -124,7 +124,7 @@ func init() {
 		fp = buildReg("F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26")
 		sp = buildReg("SP")
 		sb = buildReg("SB")
-		// gr  = buildReg("g")
+		gr = buildReg("g")
 		// cr  = buildReg("CR")
 		// ctr = buildReg("CTR")
 		// lr  = buildReg("LR")
@@ -148,7 +148,7 @@ func init() {
 		fp2cr       = regInfo{inputs: []regMask{fp, fp}}
 		fpload      = regInfo{inputs: []regMask{gp | sp | sb}, outputs: []regMask{fp}}
 		fpstore     = regInfo{inputs: []regMask{gp | sp | sb, fp}}
-		callerSave  = regMask(gp | fp)
+		callerSave  = regMask(gp | fp | gr)
 	)
 	ops := []opData{
 		{name: "ADD", argLength: 2, reg: gp21, asm: "ADD", commutative: true},     // arg0 + arg1

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

@@ -13247,7 +13247,7 @@ var opcodeTable = [...]opInfo{
 		argLen:       1,
 		clobberFlags: true,
 		reg: regInfo{
-			clobbers: 288230372393611260, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
+			clobbers: 288230372930482172, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 g F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
 		},
 	},
 	{
@@ -13260,7 +13260,7 @@ var opcodeTable = [...]opInfo{
 				{1, 1024},      // R11
 				{0, 536866813}, // SP R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29
 			},
-			clobbers: 288230372393611260, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
+			clobbers: 288230372930482172, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 g F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
 		},
 	},
 	{
@@ -13269,7 +13269,7 @@ var opcodeTable = [...]opInfo{
 		argLen:       1,
 		clobberFlags: true,
 		reg: regInfo{
-			clobbers: 288230372393611260, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
+			clobbers: 288230372930482172, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 g F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
 		},
 	},
 	{
@@ -13278,7 +13278,7 @@ var opcodeTable = [...]opInfo{
 		argLen:       1,
 		clobberFlags: true,
 		reg: regInfo{
-			clobbers: 288230372393611260, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
+			clobbers: 288230372930482172, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 g F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
 		},
 	},
 	{
@@ -13290,7 +13290,7 @@ var opcodeTable = [...]opInfo{
 			inputs: []inputInfo{
 				{0, 536866812}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29
 			},
-			clobbers: 288230372393611260, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
+			clobbers: 288230372930482172, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 g F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26
 		},
 	},
 	{

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

@@ -480,12 +480,20 @@ func (s *regAllocState) init(f *Func) {
 	if s.f.Config.ctxt.Framepointer_enabled && s.f.Config.FPReg >= 0 {
 		s.allocatable &^= 1 << uint(s.f.Config.FPReg)
 	}
+	if s.f.Config.ctxt.Flag_shared {
+		switch s.f.Config.arch {
+		case "ppc64le": // R2 already reserved.
+			s.allocatable &^= 1 << 11 // R12 -- R0 is skipped in PPC64Ops.go
+		}
+	}
 	if s.f.Config.ctxt.Flag_dynlink {
 		switch s.f.Config.arch {
 		case "amd64":
 			s.allocatable &^= 1 << 15 // R15
 		case "arm":
 			s.allocatable &^= 1 << 9 // R9
+		case "ppc64le": // R2 already reserved.
+			s.allocatable &^= 1 << 11 // R12 -- R0 is skipped in PPC64Ops.go
 		case "arm64":
 			// nothing to do?
 		case "386":

src/cmd/compile/internal/ssa/rewritePPC64.go

@@ -350,14 +350,6 @@ func rewriteValuePPC64(v *Value, config *Config) bool {
 		return rewriteValuePPC64_OpPPC64CMPconst(v, config)
 	case OpPPC64Equal:
 		return rewriteValuePPC64_OpPPC64Equal(v, config)
-	case OpPPC64FGreaterEqual:
-		return rewriteValuePPC64_OpPPC64FGreaterEqual(v, config)
-	case OpPPC64FGreaterThan:
-		return rewriteValuePPC64_OpPPC64FGreaterThan(v, config)
-	case OpPPC64FLessEqual:
-		return rewriteValuePPC64_OpPPC64FLessEqual(v, config)
-	case OpPPC64FLessThan:
-		return rewriteValuePPC64_OpPPC64FLessThan(v, config)
 	case OpPPC64GreaterEqual:
 		return rewriteValuePPC64_OpPPC64GreaterEqual(v, config)
 	case OpPPC64GreaterThan:
@@ -4178,78 +4170,6 @@ func rewriteValuePPC64_OpPPC64Equal(v *Value, config *Config) bool {
 	}
 	return false
 }
-func rewriteValuePPC64_OpPPC64FGreaterEqual(v *Value, config *Config) bool {
-	b := v.Block
-	_ = b
-	// match: (FGreaterEqual (InvertFlags x))
-	// cond:
-	// result: (FLessEqual x)
-	for {
-		v_0 := v.Args[0]
-		if v_0.Op != OpPPC64InvertFlags {
-			break
-		}
-		x := v_0.Args[0]
-		v.reset(OpPPC64FLessEqual)
-		v.AddArg(x)
-		return true
-	}
-	return false
-}
-func rewriteValuePPC64_OpPPC64FGreaterThan(v *Value, config *Config) bool {
-	b := v.Block
-	_ = b
-	// match: (FGreaterThan (InvertFlags x))
-	// cond:
-	// result: (FLessThan x)
-	for {
-		v_0 := v.Args[0]
-		if v_0.Op != OpPPC64InvertFlags {
-			break
-		}
-		x := v_0.Args[0]
-		v.reset(OpPPC64FLessThan)
-		v.AddArg(x)
-		return true
-	}
-	return false
-}
-func rewriteValuePPC64_OpPPC64FLessEqual(v *Value, config *Config) bool {
-	b := v.Block
-	_ = b
-	// match: (FLessEqual (InvertFlags x))
-	// cond:
-	// result: (FGreaterEqual x)
-	for {
-		v_0 := v.Args[0]
-		if v_0.Op != OpPPC64InvertFlags {
-			break
-		}
-		x := v_0.Args[0]
-		v.reset(OpPPC64FGreaterEqual)
-		v.AddArg(x)
-		return true
-	}
-	return false
-}
-func rewriteValuePPC64_OpPPC64FLessThan(v *Value, config *Config) bool {
-	b := v.Block
-	_ = b
-	// match: (FLessThan (InvertFlags x))
-	// cond:
-	// result: (FGreaterThan x)
-	for {
-		v_0 := v.Args[0]
-		if v_0.Op != OpPPC64InvertFlags {
-			break
-		}
-		x := v_0.Args[0]
-		v.reset(OpPPC64FGreaterThan)
-		v.AddArg(x)
-		return true
-	}
-	return false
-}
 func rewriteValuePPC64_OpPPC64GreaterEqual(v *Value, config *Config) bool {
 	b := v.Block
 	_ = b

src/cmd/internal/obj/ppc64/a.out.go

@@ -266,13 +266,13 @@ const (
 	ABC
 	ABCL
 	ABEQ
-	ABGE
+	ABGE // not LT = G/E/U
 	ABGT
-	ABLE
+	ABLE // not GT = L/E/U
 	ABLT
-	ABNE
-	ABVC
-	ABVS
+	ABNE // not EQ = L/G/U
+	ABVC // apparently Unordered-clear
+	ABVS // apparently Unordered-set
 	ACMP
 	ACMPU
 	ACNTLZW

src/cmd/internal/obj/ppc64/asm9.go

@@ -3092,9 +3092,9 @@ func opirr(ctxt *obj.Link, a obj.As) uint32 {
 	case ABNE:
 		return AOP_RRR(16<<26, 4, 2, 0)
 	case ABVC:
-		return AOP_RRR(16<<26, 4, 3, 0)
+		return AOP_RRR(16<<26, 4, 3, 0) // apparently unordered-clear
 	case ABVS:
-		return AOP_RRR(16<<26, 12, 3, 0)
+		return AOP_RRR(16<<26, 12, 3, 0) // apparently unordered-set
 
 	case ACMP:
 		return OPVCC(11, 0, 0, 0) | 1<<21 /* L=1 */

src/cmd/internal/obj/stack.go

@@ -11,7 +11,7 @@ const (
 	STACKSYSTEM = 0
 	StackSystem = STACKSYSTEM
 	StackBig    = 4096
-	StackGuard  = 720*stackGuardMultiplier + StackSystem
+	StackGuard  = 880*stackGuardMultiplier + StackSystem
 	StackSmall  = 128
 	StackLimit  = StackGuard - StackSystem - StackSmall
 )

src/runtime/stack.go

@@ -90,7 +90,7 @@ const (
 
 	// The stack guard is a pointer this many bytes above the
 	// bottom of the stack.
-	_StackGuard = 720*sys.StackGuardMultiplier + _StackSystem
+	_StackGuard = 880*sys.StackGuardMultiplier + _StackSystem
 
 	// After a stack split check the SP is allowed to be this
 	// many bytes below the stack guard. This saves an instruction

test/fixedbugs/issue15747.go

@@ -22,7 +22,7 @@ func f1(q *Q, xx []byte) interface{} { // ERROR "live at entry to f1: q xx" "liv
 	// xx was live for the first two prints but then it switched to &xx
 	// being live. We should not see plain xx again.
 	if b {
-		global = &xx // ERROR "live at call to writebarrierptr: q &xx$"
+		global = &xx // ERROR "live at call to writebarrierptr: q &xx[^x]*$"
 	}
 	xx, _, err := f2(xx, 5) // ERROR "live at call to newobject: q( d)? &xx( odata.ptr)?" "live at call to writebarrierptr: q (e|err.data err.type)$"
 	if err != nil {

test/live.go

-// +build !amd64,!arm,!amd64p32,!386,!arm64
+// +build !amd64,!arm,!amd64p32,!386,!arm64,!ppc64le
 // errorcheck -0 -l -live -wb=0
 
 // Copyright 2014 The Go Authors. All rights reserved.

test/nosplit.go

@@ -305,13 +305,13 @@ TestCases:
 				// Instead of rewriting the test cases above, adjust
 				// the first stack frame to use up the extra bytes.
 				if i == 0 {
-					size += (720 - 128) - 128
+					size += (880 - 128) - 128
 					// Noopt builds have a larger stackguard.
 					// See ../src/cmd/dist/buildruntime.go:stackGuardMultiplier
 					// This increase is included in obj.StackGuard
 					for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") {
 						if s == "-N" {
-							size += 720
+							size += 880
 						}
 					}
 				}

test/sliceopt.go

-// +build !amd64,!arm,!amd64p32,!386,!arm64
+// +build !amd64,!arm,!amd64p32,!386,!arm64,!ppc64le
 // errorcheck -0 -d=append,slice
 
 // Copyright 2015 The Go Authors. All rights reserved.