diff --git a/src/cmd/compile/internal/gc/escape.go b/src/cmd/compile/internal/gc/escape.go
index b855f4a174..3dc6b98123 100644
--- a/src/cmd/compile/internal/gc/escape.go
+++ b/src/cmd/compile/internal/gc/escape.go
@@ -371,6 +371,7 @@ func (e *Escape) stmt(n *Node) {
 		e.stmts(n.Right.Ninit)
 		e.call(e.addrs(n.List), n.Right, nil)
 	case ORETURN:
+		e.curfn.Func.numReturns++
 		results := e.curfn.Type.Results().FieldSlice()
 		for i, v := range n.List.Slice() {
 			e.assign(asNode(results[i].Nname), v, "return", n)
@@ -378,6 +379,16 @@ func (e *Escape) stmt(n *Node) {
 	case OCALLFUNC, OCALLMETH, OCALLINTER, OCLOSE, OCOPY, ODELETE, OPANIC, OPRINT, OPRINTN, ORECOVER:
 		e.call(nil, n, nil)
 	case OGO, ODEFER:
+		if n.Op == ODEFER {
+			e.curfn.Func.SetHasDefer(true)
+			e.curfn.Func.numDefers++
+			if e.curfn.Func.numDefers > maxOpenDefers {
+				// Don't allow open defers if there are more than
+				// 8 defers in the function, since we use a single
+				// byte to record active defers.
+				e.curfn.Func.SetOpenCodedDeferDisallowed(true)
+			}
+		}
 		e.stmts(n.Left.Ninit)
 		e.call(nil, n.Left, n)
 
@@ -872,8 +883,13 @@ func (e *Escape) augmentParamHole(k EscHole, where *Node) EscHole {
 	// non-transient location to avoid arguments from being
 	// transiently allocated.
 	if where.Op == ODEFER && e.loopDepth == 1 {
-		where.Esc = EscNever // force stack allocation of defer record (see ssa.go)
+		// force stack allocation of defer record, unless open-coded
+		// defers are used (see ssa.go)
+		where.Esc = EscNever
 		return e.later(k)
+	} else if where.Op == ODEFER {
+		// If any defer occurs in a loop, open-coded defers cannot be used
+		e.curfn.Func.SetOpenCodedDeferDisallowed(true)
 	}
 
 	return e.heapHole()
diff --git a/src/cmd/compile/internal/gc/main.go b/src/cmd/compile/internal/gc/main.go
index 05aac9ecb2..8806386707 100644
--- a/src/cmd/compile/internal/gc/main.go
+++ b/src/cmd/compile/internal/gc/main.go
@@ -52,6 +52,7 @@ var (
 	Debug_typecheckinl int
 	Debug_gendwarfinl  int
 	Debug_softfloat    int
+	Debug_defer        int
 )
 
 // Debug arguments.
@@ -81,6 +82,7 @@ var debugtab = []struct {
 	{"typecheckinl", "eager typechecking of inline function bodies", &Debug_typecheckinl},
 	{"dwarfinl", "print information about DWARF inlined function creation", &Debug_gendwarfinl},
 	{"softfloat", "force compiler to emit soft-float code", &Debug_softfloat},
+	{"defer", "print information about defer compilation", &Debug_defer},
 }
 
 const debugHelpHeader = `usage: -d arg[,arg]* and arg is <key>[=<value>]
diff --git a/src/cmd/compile/internal/gc/obj.go b/src/cmd/compile/internal/gc/obj.go
index be13b27892..83371fabf5 100644
--- a/src/cmd/compile/internal/gc/obj.go
+++ b/src/cmd/compile/internal/gc/obj.go
@@ -294,6 +294,9 @@ func addGCLocals() {
 			}
 			ggloblsym(x, int32(len(x.P)), attr)
 		}
+		if x := s.Func.OpenCodedDeferInfo; x != nil {
+			ggloblsym(x, int32(len(x.P)), obj.RODATA|obj.DUPOK)
+		}
 	}
 }
 
diff --git a/src/cmd/compile/internal/gc/reflect.go b/src/cmd/compile/internal/gc/reflect.go
index 9e3dca25c8..00a24f2dff 100644
--- a/src/cmd/compile/internal/gc/reflect.go
+++ b/src/cmd/compile/internal/gc/reflect.go
@@ -338,6 +338,7 @@ func deferstruct(stksize int64) *types.Type {
 		makefield("siz", types.Types[TUINT32]),
 		makefield("started", types.Types[TBOOL]),
 		makefield("heap", types.Types[TBOOL]),
+		makefield("openDefer", types.Types[TBOOL]),
 		makefield("sp", types.Types[TUINTPTR]),
 		makefield("pc", types.Types[TUINTPTR]),
 		// Note: the types here don't really matter. Defer structures
@@ -346,6 +347,9 @@ func deferstruct(stksize int64) *types.Type {
 		makefield("fn", types.Types[TUINTPTR]),
 		makefield("_panic", types.Types[TUINTPTR]),
 		makefield("link", types.Types[TUINTPTR]),
+		makefield("framepc", types.Types[TUINTPTR]),
+		makefield("varp", types.Types[TUINTPTR]),
+		makefield("fd", types.Types[TUINTPTR]),
 		makefield("args", argtype),
 	}
 
diff --git a/src/cmd/compile/internal/gc/sizeof_test.go b/src/cmd/compile/internal/gc/sizeof_test.go
index f4725c0eb2..ce4a216c2e 100644
--- a/src/cmd/compile/internal/gc/sizeof_test.go
+++ b/src/cmd/compile/internal/gc/sizeof_test.go
@@ -20,7 +20,7 @@ func TestSizeof(t *testing.T) {
 		_32bit uintptr     // size on 32bit platforms
 		_64bit uintptr     // size on 64bit platforms
 	}{
-		{Func{}, 116, 208},
+		{Func{}, 124, 224},
 		{Name{}, 32, 56},
 		{Param{}, 24, 48},
 		{Node{}, 76, 128},
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index dd8dacd149..200cca1063 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -29,6 +29,10 @@ var ssaDumpStdout bool // whether to dump to stdout
 var ssaDumpCFG string  // generate CFGs for these phases
 const ssaDumpFile = "ssa.html"
 
+// The max number of defers in a function using open-coded defers. We enforce this
+// limit because the deferBits bitmask is currently a single byte (to minimize code size)
+const maxOpenDefers = 8
+
 // ssaDumpInlined holds all inlined functions when ssaDump contains a function name.
 var ssaDumpInlined []*Node
 
@@ -165,6 +169,107 @@ func initssaconfig() {
 	SigPanic = sysfunc("sigpanic")
 }
 
+// getParam returns the Field of ith param of node n (which is a
+// function/method/interface call), where the receiver of a method call is
+// considered as the 0th parameter. This does not include the receiver of an
+// interface call.
+func getParam(n *Node, i int) *types.Field {
+	t := n.Left.Type
+	if n.Op == OCALLMETH {
+		if i == 0 {
+			return t.Recv()
+		}
+		return t.Params().Field(i - 1)
+	}
+	return t.Params().Field(i)
+}
+
+// dvarint writes a varint v to the funcdata in symbol x and returns the new offset
+func dvarint(x *obj.LSym, off int, v int64) int {
+	if v < 0 || v > 1e9 {
+		panic(fmt.Sprintf("dvarint: bad offset for funcdata - %v", v))
+	}
+	if v < 1<<7 {
+		return duint8(x, off, uint8(v))
+	}
+	off = duint8(x, off, uint8((v&127)|128))
+	if v < 1<<14 {
+		return duint8(x, off, uint8(v>>7))
+	}
+	off = duint8(x, off, uint8(((v>>7)&127)|128))
+	if v < 1<<21 {
+		return duint8(x, off, uint8(v>>14))
+	}
+	off = duint8(x, off, uint8(((v>>14)&127)|128))
+	if v < 1<<28 {
+		return duint8(x, off, uint8(v>>21))
+	}
+	off = duint8(x, off, uint8(((v>>21)&127)|128))
+	return duint8(x, off, uint8(v>>28))
+}
+
+// emitOpenDeferInfo emits FUNCDATA information about the defers in a function
+// that is using open-coded defers.  This funcdata is used to determine the active
+// defers in a function and execute those defers during panic processing.
+//
+// The funcdata is all encoded in varints (since values will almost always be less
+// than 128, but stack offsets could potentially be up to 2Gbyte). All "locations"
+// for stack variables are specified as the number of bytes below varp for their
+// starting address. The format is:
+//
+//  - Max total argument size among all the defers
+//  - Location of the deferBits variable
+//  - Number of defers in the function
+//  - Information about each defer call, in reverse order of appearance in the function:
+//    - Total argument size of the call
+//    - Location of the closure value to call
+//    - 1 or 0 to indicate if there is a receiver for the call
+//      - If yes, then the location of the receiver value
+//    - Number of arguments
+//    - Information about each argument
+//      - Location of the stored defer argument in this function's frame
+//      - Size of the argument
+//      - Offset of where argument should be placed in the args frame when making call
+func emitOpenDeferInfo(s state) {
+	x := Ctxt.Lookup(s.curfn.Func.lsym.Name + ".opendefer")
+	s.curfn.Func.lsym.Func.OpenCodedDeferInfo = x
+	off := 0
+
+	// Compute maxargsize (max size of arguments for all defers)
+	// first, so we can output it first to the funcdata
+	var maxargsize int64
+	for i := len(s.opendefers) - 1; i >= 0; i-- {
+		r := s.opendefers[i]
+		argsize := r.n.Left.Type.ArgWidth()
+		if argsize > maxargsize {
+			maxargsize = argsize
+		}
+	}
+	off = dvarint(x, off, maxargsize)
+	off = dvarint(x, off, -s.deferBitsTemp.Xoffset)
+	off = dvarint(x, off, int64(len(s.opendefers)))
+
+	// Write in reverse-order, for ease of running in that order at runtime
+	for i := len(s.opendefers) - 1; i >= 0; i-- {
+		r := s.opendefers[i]
+		off = dvarint(x, off, r.n.Left.Type.ArgWidth())
+		off = dvarint(x, off, -r.closureNode.Xoffset)
+		if r.rcvrNode != nil {
+			off = dvarint(x, off, 1)
+			off = dvarint(x, off, -r.rcvrNode.Xoffset)
+		} else {
+			off = dvarint(x, off, 0)
+		}
+		off = dvarint(x, off, int64(len(r.argNodes)))
+		for j, arg := range r.argNodes {
+			f := getParam(r.n, j)
+			off = dvarint(x, off, -arg.Xoffset)
+			off = dvarint(x, off, f.Type.Size())
+			off = dvarint(x, off, f.Offset)
+		}
+	}
+}
+
 // buildssa builds an SSA function for fn.
 // worker indicates which of the backend workers is doing the processing.
 func buildssa(fn *Node, worker int) *ssa.Func {
@@ -227,11 +332,48 @@ func buildssa(fn *Node, worker int) *ssa.Func {
 	s.labeledNodes = map[*Node]*ssaLabel{}
 	s.fwdVars = map[*Node]*ssa.Value{}
 	s.startmem = s.entryNewValue0(ssa.OpInitMem, types.TypeMem)
+
+	s.hasOpenDefers = Debug['N'] == 0 && s.hasdefer && !s.curfn.Func.OpenCodedDeferDisallowed()
+	if s.hasOpenDefers && s.curfn.Func.Exit.Len() > 0 {
+		// Skip doing open defers if there is any extra exit code (likely
+		// copying heap-allocated return values or race detection), since
+		// we will not generate that code in the case of the extra
+		// deferreturn/ret segment.
+		s.hasOpenDefers = false
+	}
+	if s.hasOpenDefers &&
+		s.curfn.Func.numReturns*s.curfn.Func.numDefers > 15 {
+		// Since we are generating defer calls at every exit for
+		// open-coded defers, skip doing open-coded defers if there are
+		// too many returns (especially if there are multiple defers).
+		// Open-coded defers are most important for improving performance
+		// for smaller functions (which don't have many returns).
+		s.hasOpenDefers = false
+	}
+
 	s.sp = s.entryNewValue0(ssa.OpSP, types.Types[TUINTPTR]) // TODO: use generic pointer type (unsafe.Pointer?) instead
 	s.sb = s.entryNewValue0(ssa.OpSB, types.Types[TUINTPTR])
 
 	s.startBlock(s.f.Entry)
 	s.vars[&memVar] = s.startmem
+	if s.hasOpenDefers {
+		// Create the deferBits variable and stack slot.  deferBits is a
+		// bitmask showing which of the open-coded defers in this function
+		// have been activated.
+		deferBitsTemp := tempAt(src.NoXPos, s.curfn, types.Types[TUINT8])
+		s.deferBitsTemp = deferBitsTemp
+		// For this value, AuxInt is initialized to zero by default
+		startDeferBits := s.entryNewValue0(ssa.OpConst8, types.Types[TUINT8])
+		s.vars[&deferBitsVar] = startDeferBits
+		s.deferBitsAddr = s.addr(deferBitsTemp, false)
+		s.store(types.Types[TUINT8], s.deferBitsAddr, startDeferBits)
+		// Make sure that the deferBits stack slot is kept alive (for use
+		// by panics) and stores to deferBits are not eliminated, even if
+		// all checking code on deferBits in the function exit can be
+		// eliminated, because the defer statements were all
+		// unconditional.
+		s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, deferBitsTemp, s.mem(), false)
+	}
 
 	// Generate addresses of local declarations
 	s.decladdrs = map[*Node]*ssa.Value{}
@@ -287,6 +429,11 @@ func buildssa(fn *Node, worker int) *ssa.Func {
 
 	// Main call to ssa package to compile function
 	ssa.Compile(s.f)
+
+	if s.hasOpenDefers {
+		emitOpenDeferInfo(s)
+	}
+
 	return s.f
 }
 
@@ -375,6 +522,29 @@ func (s *state) updateUnsetPredPos(b *ssa.Block) {
 	}
 }
 
+// Information about each open-coded defer.
+type openDeferInfo struct {
+	// The ODEFER node representing the function call of the defer
+	n *Node
+	// If defer call is closure call, the address of the argtmp where the
+	// closure is stored.
+	closure *ssa.Value
+	// The node representing the argtmp where the closure is stored - used for
+	// function, method, or interface call, to store a closure that panic
+	// processing can use for this defer.
+	closureNode *Node
+	// If defer call is interface call, the address of the argtmp where the
+	// receiver is stored
+	rcvr *ssa.Value
+	// The node representing the argtmp where the receiver is stored
+	rcvrNode *Node
+	// The addresses of the argtmps where the evaluated arguments of the defer
+	// function call are stored.
+	argVals []*ssa.Value
+	// The nodes representing the argtmps where the args of the defer are stored
+	argNodes []*Node
+}
+
 type state struct {
 	// configuration (arch) information
 	config *ssa.Config
@@ -416,6 +586,9 @@ type state struct {
 	startmem *ssa.Value
 	sp       *ssa.Value
 	sb       *ssa.Value
+	// value representing address of where deferBits autotmp is stored
+	deferBitsAddr *ssa.Value
+	deferBitsTemp *Node
 
 	// line number stack. The current line number is top of stack
 	line []src.XPos
@@ -432,6 +605,19 @@ type state struct {
 	cgoUnsafeArgs bool
 	hasdefer      bool // whether the function contains a defer statement
 	softFloat     bool
+	hasOpenDefers bool // whether we are doing open-coded defers
+
+	// If doing open-coded defers, list of info about the defer calls in
+	// scanning order. Hence, at exit we should run these defers in reverse
+	// order of this list
+	opendefers []*openDeferInfo
+	// For open-coded defers, this is the beginning and end blocks of the last
+	// defer exit code that we have generated so far. We use these to share
+	// code between exits if the shareDeferExits option (disabled by default)
+	// is on.
+	lastDeferExit       *ssa.Block // Entry block of last defer exit code we generated
+	lastDeferFinalBlock *ssa.Block // Final block of last defer exit code we generated
+	lastDeferCount      int        // Number of defers encountered at that point
 }
 
 type funcLine struct {
@@ -469,12 +655,13 @@ var (
 	memVar = Node{Op: ONAME, Sym: &types.Sym{Name: "mem"}}
 
 	// dummy nodes for temporary variables
-	ptrVar    = Node{Op: ONAME, Sym: &types.Sym{Name: "ptr"}}
-	lenVar    = Node{Op: ONAME, Sym: &types.Sym{Name: "len"}}
-	newlenVar = Node{Op: ONAME, Sym: &types.Sym{Name: "newlen"}}
-	capVar    = Node{Op: ONAME, Sym: &types.Sym{Name: "cap"}}
-	typVar    = Node{Op: ONAME, Sym: &types.Sym{Name: "typ"}}
-	okVar     = Node{Op: ONAME, Sym: &types.Sym{Name: "ok"}}
+	ptrVar       = Node{Op: ONAME, Sym: &types.Sym{Name: "ptr"}}
+	lenVar       = Node{Op: ONAME, Sym: &types.Sym{Name: "len"}}
+	newlenVar    = Node{Op: ONAME, Sym: &types.Sym{Name: "newlen"}}
+	capVar       = Node{Op: ONAME, Sym: &types.Sym{Name: "cap"}}
+	typVar       = Node{Op: ONAME, Sym: &types.Sym{Name: "typ"}}
+	okVar        = Node{Op: ONAME, Sym: &types.Sym{Name: "ok"}}
+	deferBitsVar = Node{Op: ONAME, Sym: &types.Sym{Name: "deferBits"}}
 )
 
 // startBlock sets the current block we're generating code in to b.
@@ -865,11 +1052,27 @@ func (s *state) stmt(n *Node) {
 			}
 		}
 	case ODEFER:
-		d := callDefer
-		if n.Esc == EscNever {
-			d = callDeferStack
+		if Debug_defer > 0 {
+			var defertype string
+			if s.hasOpenDefers {
+				defertype = "open-coded"
+			} else if n.Esc == EscNever {
+				defertype = "stack-allocated"
+			} else {
+				defertype = "heap-allocated"
+			}
+			Warnl(n.Pos, "defer: %s defer in function %s",
+				defertype, s.curfn.funcname())
+		}
+		if s.hasOpenDefers {
+			s.openDeferRecord(n.Left)
+		} else {
+			d := callDefer
+			if n.Esc == EscNever {
+				d = callDeferStack
+			}
+			s.call(n.Left, d)
 		}
-		s.call(n.Left, d)
 	case OGO:
 		s.call(n.Left, callGo)
 
@@ -1286,12 +1489,28 @@ func (s *state) stmt(n *Node) {
 	}
 }
 
+// If true, share as many open-coded defer exits as possible (with the downside of
+// worse line-number information)
+const shareDeferExits = false
+
 // exit processes any code that needs to be generated just before returning.
 // It returns a BlockRet block that ends the control flow. Its control value
 // will be set to the final memory state.
 func (s *state) exit() *ssa.Block {
 	if s.hasdefer {
-		s.rtcall(Deferreturn, true, nil)
+		if s.hasOpenDefers {
+			if shareDeferExits && s.lastDeferExit != nil && len(s.opendefers) == s.lastDeferCount {
+				if s.curBlock.Kind != ssa.BlockPlain {
+					panic("Block for an exit should be BlockPlain")
+				}
+				s.curBlock.AddEdgeTo(s.lastDeferExit)
+				s.endBlock()
+				return s.lastDeferFinalBlock
+			}
+			s.openDeferExit()
+		} else {
+			s.rtcall(Deferreturn, true, nil)
+		}
 	}
 
 	// Run exit code. Typically, this code copies heap-allocated PPARAMOUT
@@ -1314,6 +1533,9 @@ func (s *state) exit() *ssa.Block {
 	b := s.endBlock()
 	b.Kind = ssa.BlockRet
 	b.SetControl(m)
+	if s.hasdefer && s.hasOpenDefers {
+		s.lastDeferFinalBlock = b
+	}
 	return b
 }
 
@@ -3764,6 +3986,230 @@ func (s *state) intrinsicArgs(n *Node) []*ssa.Value {
 	return args
 }
 
+// openDeferRecord adds code to evaluate and store the args for an open-code defer
+// call, and records info about the defer, so we can generate proper code on the
+// exit paths. n is the sub-node of the defer node that is the actual function
+// call. We will also record funcdata information on where the args are stored
+// (as well as the deferBits variable), and this will enable us to run the proper
+// defer calls during panics.
+func (s *state) openDeferRecord(n *Node) {
+	index := len(s.opendefers)
+
+	// Do any needed expression evaluation for the args (including the
+	// receiver, if any). This may be evaluating something like 'autotmp_3 =
+	// once.mutex'. Such a statement will create a mapping in s.vars[] from
+	// the autotmp name to the evaluated SSA arg value, but won't do any
+	// stores to the stack.
+	s.stmtList(n.List)
+
+	args := []*ssa.Value{}
+	argNodes := []*Node{}
+
+	opendefer := &openDeferInfo{
+		n: n,
+	}
+	fn := n.Left
+	if n.Op == OCALLFUNC {
+		// We must always store the function value in a stack slot for the
+		// runtime panic code to use. But in the defer exit code, we will
+		// call the function directly if it is a static function.
+		closureVal := s.expr(fn)
+		closure := s.openDeferSave(fn, fn.Type, closureVal)
+		opendefer.closureNode = closure.Aux.(*Node)
+		if !(fn.Op == ONAME && fn.Class() == PFUNC) {
+			opendefer.closure = closure
+		}
+	} else if n.Op == OCALLMETH {
+		if fn.Op != ODOTMETH {
+			Fatalf("OCALLMETH: n.Left not an ODOTMETH: %v", fn)
+		}
+		closureVal := s.getMethodClosure(fn)
+		// We must always store the function value in a stack slot for the
+		// runtime panic code to use. But in the defer exit code, we will
+		// call the method directly.
+		closure := s.openDeferSave(fn, fn.Type, closureVal)
+		opendefer.closureNode = closure.Aux.(*Node)
+	} else {
+		if fn.Op != ODOTINTER {
+			Fatalf("OCALLINTER: n.Left not an ODOTINTER: %v", fn.Op)
+		}
+		closure, rcvr := s.getClosureAndRcvr(fn)
+		opendefer.closure = s.openDeferSave(fn, closure.Type, closure)
+		// Important to get the receiver type correct, so it is recognized
+		// as a pointer for GC purposes.
+		opendefer.rcvr = s.openDeferSave(nil, fn.Type.Recv().Type, rcvr)
+		opendefer.closureNode = opendefer.closure.Aux.(*Node)
+		opendefer.rcvrNode = opendefer.rcvr.Aux.(*Node)
+	}
+	for _, argn := range n.Rlist.Slice() {
+		v := s.openDeferSave(argn, argn.Type, s.expr(argn))
+		args = append(args, v)
+		argNodes = append(argNodes, v.Aux.(*Node))
+	}
+	opendefer.argVals = args
+	opendefer.argNodes = argNodes
+	s.opendefers = append(s.opendefers, opendefer)
+
+	// Update deferBits only after evaluation and storage to stack of
+	// args/receiver/interface is successful.
+	bitvalue := s.constInt8(types.Types[TUINT8], 1<<uint(index))
+	newDeferBits := s.newValue2(ssa.OpOr8, types.Types[TUINT8], s.variable(&deferBitsVar, types.Types[TUINT8]), bitvalue)
+	s.vars[&deferBitsVar] = newDeferBits
+	s.store(types.Types[TUINT8], s.deferBitsAddr, newDeferBits)
+}
+
+// openDeferSave generates SSA nodes to store a value val (with type t) for an
+// open-coded defer on the stack at an explicit autotmp location, so it can be
+// reloaded and used for the appropriate call on exit. n is the associated node,
+// which is only needed if the associated type is non-SSAable. It returns an SSA
+// value representing a pointer to the stack location.
+func (s *state) openDeferSave(n *Node, t *types.Type, val *ssa.Value) *ssa.Value {
+	argTemp := tempAt(val.Pos.WithNotStmt(), s.curfn, t)
+	var addrArgTemp *ssa.Value
+	// Use OpVarLive to make sure stack slots for the args, etc. are not
+	// removed by dead-store elimination
+	if s.curBlock.ID != s.f.Entry.ID {
+		// Force the argtmp storing this defer function/receiver/arg to be
+		// declared in the entry block, so that it will be live for the
+		// defer exit code (which will actually access it only if the
+		// associated defer call has been activated).
+		s.defvars[s.f.Entry.ID][&memVar] = s.entryNewValue1A(ssa.OpVarDef, types.TypeMem, argTemp, s.defvars[s.f.Entry.ID][&memVar])
+		s.defvars[s.f.Entry.ID][&memVar] = s.entryNewValue1A(ssa.OpVarLive, types.TypeMem, argTemp, s.defvars[s.f.Entry.ID][&memVar])
+		addrArgTemp = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(argTemp.Type), argTemp, s.sp, s.defvars[s.f.Entry.ID][&memVar])
+	} else {
+		// Special case if we're still in the entry block. We can't use
+		// the above code, since s.defvars[s.f.Entry.ID] isn't defined
+		// until we end the entry block with s.endBlock().
+		s.vars[&memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, argTemp, s.mem(), false)
+		s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, argTemp, s.mem(), false)
+		addrArgTemp = s.newValue2Apos(ssa.OpLocalAddr, types.NewPtr(argTemp.Type), argTemp, s.sp, s.mem(), false)
+	}
+	if types.Haspointers(t) {
+		// Since we may use this argTemp during exit depending on the
+		// deferBits, we must define it unconditionally on entry.
+		// Therefore, we must make sure it is zeroed out in the entry
+		// block if it contains pointers, else GC may wrongly follow an
+		// uninitialized pointer value.
+		argTemp.Name.SetNeedzero(true)
+	}
+	if !canSSAType(t) {
+		if n.Op != ONAME {
+			panic(fmt.Sprintf("Non-SSAable value should be a named location: %v", n))
+		}
+		a := s.addr(n, false)
+		s.move(t, addrArgTemp, a)
+		return addrArgTemp
+	}
+	// We are storing to the stack, hence we can avoid the full checks in
+	// storeType() (no write barrier) and do a simple store().
+	s.store(t, addrArgTemp, val)
+	return addrArgTemp
+}
+
+// openDeferExit generates SSA for processing all the open coded defers at exit.
+// The code involves loading deferBits, and checking each of the bits to see if
+// the corresponding defer statement was executed. For each bit that is turned
+// on, the associated defer call is made.
+func (s *state) openDeferExit() {
+	deferExit := s.f.NewBlock(ssa.BlockPlain)
+	s.endBlock().AddEdgeTo(deferExit)
+	s.startBlock(deferExit)
+	s.lastDeferExit = deferExit
+	s.lastDeferCount = len(s.opendefers)
+	zeroval := s.constInt8(types.Types[TUINT8], 0)
+	// Test for and run defers in reverse order
+	for i := len(s.opendefers) - 1; i >= 0; i-- {
+		r := s.opendefers[i]
+		bCond := s.f.NewBlock(ssa.BlockPlain)
+		bEnd := s.f.NewBlock(ssa.BlockPlain)
+
+		deferBits := s.variable(&deferBitsVar, types.Types[TUINT8])
+		// Generate code to check if the bit associated with the current
+		// defer is set.
+		bitval := s.constInt8(types.Types[TUINT8], 1<<uint(i))
+		andval := s.newValue2(ssa.OpAnd8, types.Types[TUINT8], deferBits, bitval)
+		eqVal := s.newValue2(ssa.OpEq8, types.Types[TBOOL], andval, zeroval)
+		b := s.endBlock()
+		b.Kind = ssa.BlockIf
+		b.SetControl(eqVal)
+		b.AddEdgeTo(bEnd)
+		b.AddEdgeTo(bCond)
+		bCond.AddEdgeTo(bEnd)
+		s.startBlock(bCond)
+
+		// Clear this bit in deferBits and force store back to stack, so
+		// we will not try to re-run this defer call if this defer call panics.
+		nbitval := s.newValue1(ssa.OpCom8, types.Types[TUINT8], bitval)
+		maskedval := s.newValue2(ssa.OpAnd8, types.Types[TUINT8], deferBits, nbitval)
+		s.store(types.Types[TUINT8], s.deferBitsAddr, maskedval)
+		// Use this value for following tests, so we keep previous
+		// bits cleared.
+		s.vars[&deferBitsVar] = maskedval
+
+		// Generate code to call the function call of the defer, using the
+		// closure/receiver/args that were stored in argtmps at the point
+		// of the defer statement.
+		argStart := Ctxt.FixedFrameSize()
+		fn := r.n.Left
+		stksize := fn.Type.ArgWidth()
+		if r.rcvr != nil {
+			// rcvr in case of OCALLINTER
+			v := s.load(r.rcvr.Type.Elem(), r.rcvr)
+			addr := s.constOffPtrSP(s.f.Config.Types.UintptrPtr, argStart)
+			s.store(types.Types[TUINTPTR], addr, v)
+		}
+		for j, argAddrVal := range r.argVals {
+			f := getParam(r.n, j)
+			pt := types.NewPtr(f.Type)
+			addr := s.constOffPtrSP(pt, argStart+f.Offset)
+			if !canSSAType(f.Type) {
+				s.move(f.Type, addr, argAddrVal)
+			} else {
+				argVal := s.load(f.Type, argAddrVal)
+				s.storeType(f.Type, addr, argVal, 0, false)
+			}
+		}
+		var call *ssa.Value
+		if r.closure != nil {
+			v := s.load(r.closure.Type.Elem(), r.closure)
+			s.maybeNilCheckClosure(v, callDefer)
+			codeptr := s.rawLoad(types.Types[TUINTPTR], v)
+			call = s.newValue3(ssa.OpClosureCall, types.TypeMem, codeptr, v, s.mem())
+		} else {
+			// Do a static call if the original call was a static function or method
+			call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, fn.Sym.Linksym(), s.mem())
+		}
+		call.AuxInt = stksize
+		s.vars[&memVar] = call
+		// Make sure that the stack slots with pointers are kept live
+		// through the call (which is a pre-emption point). Also, we will
+		// use the first call of the last defer exit to compute liveness
+		// for the deferreturn, so we want all stack slots to be live.
+		if r.closureNode != nil {
+			s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, r.closureNode, s.mem(), false)
+		}
+		if r.rcvrNode != nil {
+			if types.Haspointers(r.rcvrNode.Type) {
+				s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, r.rcvrNode, s.mem(), false)
+			}
+		}
+		for _, argNode := range r.argNodes {
+			if types.Haspointers(argNode.Type) {
+				s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, argNode, s.mem(), false)
+			}
+		}
+
+		if i == len(s.opendefers)-1 {
+			// Record the call of the first defer. This will be used
+			// to set liveness info for the deferreturn (which is also
+			// used for any location that causes a runtime panic)
+			s.f.LastDeferExit = call
+		}
+		s.endBlock()
+		s.startBlock(bEnd)
+	}
+}
+
 // Calls the function n using the specified call type.
 // Returns the address of the return value (or nil if none).
 func (s *state) call(n *Node, k callKind) *ssa.Value {
@@ -3779,11 +4225,10 @@ func (s *state) call(n *Node, k callKind) *ssa.Value {
 			break
 		}
 		closure = s.expr(fn)
-		if k != callDefer && k != callDeferStack && (thearch.LinkArch.Family == sys.Wasm || objabi.GOOS == "aix" && k != callGo) {
-			// Deferred nil function needs to panic when the function is invoked, not the point of defer statement.
-			// On AIX, the closure needs to be verified as fn can be nil, except if it's a call go. This needs to be handled by the runtime to have the "go of nil func value" error.
-			// TODO(neelance): On other architectures this should be eliminated by the optimization steps
-			s.nilCheck(closure)
+		if k != callDefer && k != callDeferStack {
+			// Deferred nil function needs to panic when the function is invoked,
+			// not the point of defer statement.
+			s.maybeNilCheckClosure(closure, k)
 		}
 	case OCALLMETH:
 		if fn.Op != ODOTMETH {
@@ -3793,35 +4238,20 @@ func (s *state) call(n *Node, k callKind) *ssa.Value {
 			sym = fn.Sym
 			break
 		}
-		// Make a name n2 for the function.
-		// fn.Sym might be sync.(*Mutex).Unlock.
-		// Make a PFUNC node out of that, then evaluate it.
-		// We get back an SSA value representing &sync.(*Mutex).Unlock·f.
-		// We can then pass that to defer or go.
-		n2 := newnamel(fn.Pos, fn.Sym)
-		n2.Name.Curfn = s.curfn
-		n2.SetClass(PFUNC)
-		// n2.Sym already existed, so it's already marked as a function.
-		n2.Pos = fn.Pos
-		n2.Type = types.Types[TUINT8] // dummy type for a static closure. Could use runtime.funcval if we had it.
-		closure = s.expr(n2)
+		closure = s.getMethodClosure(fn)
 		// Note: receiver is already present in n.Rlist, so we don't
 		// want to set it here.
 	case OCALLINTER:
 		if fn.Op != ODOTINTER {
 			s.Fatalf("OCALLINTER: n.Left not an ODOTINTER: %v", fn.Op)
 		}
-		i := s.expr(fn.Left)
-		itab := s.newValue1(ssa.OpITab, types.Types[TUINTPTR], i)
-		s.nilCheck(itab)
-		itabidx := fn.Xoffset + 2*int64(Widthptr) + 8 // offset of fun field in runtime.itab
-		itab = s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.UintptrPtr, itabidx, itab)
+		var iclosure *ssa.Value
+		iclosure, rcvr = s.getClosureAndRcvr(fn)
 		if k == callNormal {
-			codeptr = s.load(types.Types[TUINTPTR], itab)
+			codeptr = s.load(types.Types[TUINTPTR], iclosure)
 		} else {
-			closure = itab
+			closure = iclosure
 		}
-		rcvr = s.newValue1(ssa.OpIData, types.Types[TUINTPTR], i)
 	}
 	dowidth(fn.Type)
 	stksize := fn.Type.ArgWidth() // includes receiver, args, and results
@@ -3847,18 +4277,22 @@ func (s *state) call(n *Node, k callKind) *ssa.Value {
 			s.constInt32(types.Types[TUINT32], int32(stksize)))
 		// 1: started, set in deferprocStack
 		// 2: heap, set in deferprocStack
-		// 3: sp, set in deferprocStack
-		// 4: pc, set in deferprocStack
-		// 5: fn
+		// 3: openDefer
+		// 4: sp, set in deferprocStack
+		// 5: pc, set in deferprocStack
+		// 6: fn
 		s.store(closure.Type,
-			s.newValue1I(ssa.OpOffPtr, closure.Type.PtrTo(), t.FieldOff(5), addr),
+			s.newValue1I(ssa.OpOffPtr, closure.Type.PtrTo(), t.FieldOff(6), addr),
 			closure)
-		// 6: panic, set in deferprocStack
-		// 7: link, set in deferprocStack
+		// 7: panic, set in deferprocStack
+		// 8: link, set in deferprocStack
+		// 9: framepc
+		// 10: varp
+		// 11: fd
 
 		// Then, store all the arguments of the defer call.
 		ft := fn.Type
-		off := t.FieldOff(8)
+		off := t.FieldOff(12)
 		args := n.Rlist.Slice()
 
 		// Set receiver (for interface calls). Always a pointer.
@@ -3973,6 +4407,44 @@ func (s *state) call(n *Node, k callKind) *ssa.Value {
 	return s.constOffPtrSP(types.NewPtr(fp.Type), fp.Offset+Ctxt.FixedFrameSize())
 }
 
+// maybeNilCheckClosure checks if a nil check of a closure is needed in some
+// architecture-dependent situations and, if so, emits the nil check.
+func (s *state) maybeNilCheckClosure(closure *ssa.Value, k callKind) {
+	if thearch.LinkArch.Family == sys.Wasm || objabi.GOOS == "aix" && k != callGo {
+		// On AIX, the closure needs to be verified as fn can be nil, except if it's a call go. This needs to be handled by the runtime to have the "go of nil func value" error.
+		// TODO(neelance): On other architectures this should be eliminated by the optimization steps
+		s.nilCheck(closure)
+	}
+}
+
+// getMethodClosure returns a value representing the closure for a method call
+func (s *state) getMethodClosure(fn *Node) *ssa.Value {
+	// Make a name n2 for the function.
+	// fn.Sym might be sync.(*Mutex).Unlock.
+	// Make a PFUNC node out of that, then evaluate it.
+	// We get back an SSA value representing &sync.(*Mutex).Unlock·f.
+	// We can then pass that to defer or go.
+	n2 := newnamel(fn.Pos, fn.Sym)
+	n2.Name.Curfn = s.curfn
+	n2.SetClass(PFUNC)
+	// n2.Sym already existed, so it's already marked as a function.
+	n2.Pos = fn.Pos
+	n2.Type = types.Types[TUINT8] // dummy type for a static closure. Could use runtime.funcval if we had it.
+	return s.expr(n2)
+}
+
+// getClosureAndRcvr returns values for the appropriate closure and receiver of an
+// interface call
+func (s *state) getClosureAndRcvr(fn *Node) (*ssa.Value, *ssa.Value) {
+	i := s.expr(fn.Left)
+	itab := s.newValue1(ssa.OpITab, types.Types[TUINTPTR], i)
+	s.nilCheck(itab)
+	itabidx := fn.Xoffset + 2*int64(Widthptr) + 8 // offset of fun field in runtime.itab
+	closure := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.UintptrPtr, itabidx, itab)
+	rcvr := s.newValue1(ssa.OpIData, types.Types[TUINTPTR], i)
+	return closure, rcvr
+}
+
 // etypesign returns the signed-ness of e, for integer/pointer etypes.
 // -1 means signed, +1 means unsigned, 0 means non-integer/non-pointer.
 func etypesign(e types.EType) int8 {
@@ -5146,6 +5618,16 @@ func (s *state) addNamedValue(n *Node, v *ssa.Value) {
 	s.f.NamedValues[loc] = append(values, v)
 }
 
+// Generate a disconnected call to a runtime routine and a return.
+func gencallret(pp *Progs, sym *obj.LSym) *obj.Prog {
+	p := pp.Prog(obj.ACALL)
+	p.To.Type = obj.TYPE_MEM
+	p.To.Name = obj.NAME_EXTERN
+	p.To.Sym = sym
+	p = pp.Prog(obj.ARET)
+	return p
+}
+
 // Branch is an unresolved branch.
 type Branch struct {
 	P *obj.Prog  // branch instruction
@@ -5181,6 +5663,11 @@ type SSAGenState struct {
 
 	// wasm: The number of values on the WebAssembly stack. This is only used as a safeguard.
 	OnWasmStackSkipped int
+
+	// Liveness index for the first function call in the final defer exit code
+	// path that we generated. All defer functions and args should be live at
+	// this point. This will be used to set the liveness for the deferreturn.
+	lastDeferLiveness LivenessIndex
 }
 
 // Prog appends a new Prog.
@@ -5308,6 +5795,17 @@ func genssa(f *ssa.Func, pp *Progs) {
 	s.livenessMap = liveness(e, f, pp)
 	emitStackObjects(e, pp)
 
+	openDeferInfo := e.curfn.Func.lsym.Func.OpenCodedDeferInfo
+	if openDeferInfo != nil {
+		// This function uses open-coded defers -- write out the funcdata
+		// info that we computed at the end of genssa.
+		p := pp.Prog(obj.AFUNCDATA)
+		Addrconst(&p.From, objabi.FUNCDATA_OpenCodedDeferInfo)
+		p.To.Type = obj.TYPE_MEM
+		p.To.Name = obj.NAME_EXTERN
+		p.To.Sym = openDeferInfo
+	}
+
 	// Remember where each block starts.
 	s.bstart = make([]*obj.Prog, f.NumBlocks())
 	s.pp = pp
@@ -5372,6 +5870,12 @@ func genssa(f *ssa.Func, pp *Progs) {
 			// Attach this safe point to the next
 			// instruction.
 			s.pp.nextLive = s.livenessMap.Get(v)
+
+			// Remember the liveness index of the first defer call of
+			// the last defer exit
+			if v.Block.Func.LastDeferExit != nil && v == v.Block.Func.LastDeferExit {
+				s.lastDeferLiveness = s.pp.nextLive
+			}
 			switch v.Op {
 			case ssa.OpInitMem:
 				// memory arg needs no code
@@ -5455,6 +5959,13 @@ func genssa(f *ssa.Func, pp *Progs) {
 		// nop (which will never execute) after the call.
 		thearch.Ginsnop(pp)
 	}
+	if openDeferInfo != nil {
+		// When doing open-coded defers, generate a disconnected call to
+		// deferreturn and a return. This will be used to during panic
+		// recovery to unwind the stack and return back to the runtime.
+		s.pp.nextLive = s.lastDeferLiveness
+		gencallret(pp, Deferreturn)
+	}
 
 	if inlMarks != nil {
 		// We have some inline marks. Try to find other instructions we're
diff --git a/src/cmd/compile/internal/gc/syntax.go b/src/cmd/compile/internal/gc/syntax.go
index 98903100fc..e0137acfb7 100644
--- a/src/cmd/compile/internal/gc/syntax.go
+++ b/src/cmd/compile/internal/gc/syntax.go
@@ -491,7 +491,9 @@ type Func struct {
 
 	Pragma syntax.Pragma // go:xxx function annotations
 
-	flags bitset16
+	flags      bitset16
+	numDefers  int // number of defer calls in the function
+	numReturns int // number of explicit returns in the function
 
 	// nwbrCalls records the LSyms of functions called by this
 	// function for go:nowritebarrierrec analysis. Only filled in
@@ -527,34 +529,37 @@ const (
 	funcNeedctxt                  // function uses context register (has closure variables)
 	funcReflectMethod             // function calls reflect.Type.Method or MethodByName
 	funcIsHiddenClosure
-	funcHasDefer            // contains a defer statement
-	funcNilCheckDisabled    // disable nil checks when compiling this function
-	funcInlinabilityChecked // inliner has already determined whether the function is inlinable
-	funcExportInline        // include inline body in export data
-	funcInstrumentBody      // add race/msan instrumentation during SSA construction
+	funcHasDefer                 // contains a defer statement
+	funcNilCheckDisabled         // disable nil checks when compiling this function
+	funcInlinabilityChecked      // inliner has already determined whether the function is inlinable
+	funcExportInline             // include inline body in export data
+	funcInstrumentBody           // add race/msan instrumentation during SSA construction
+	funcOpenCodedDeferDisallowed // can't do open-coded defers
 )
 
-func (f *Func) Dupok() bool               { return f.flags&funcDupok != 0 }
-func (f *Func) Wrapper() bool             { return f.flags&funcWrapper != 0 }
-func (f *Func) Needctxt() bool            { return f.flags&funcNeedctxt != 0 }
-func (f *Func) ReflectMethod() bool       { return f.flags&funcReflectMethod != 0 }
-func (f *Func) IsHiddenClosure() bool     { return f.flags&funcIsHiddenClosure != 0 }
-func (f *Func) HasDefer() bool            { return f.flags&funcHasDefer != 0 }
-func (f *Func) NilCheckDisabled() bool    { return f.flags&funcNilCheckDisabled != 0 }
-func (f *Func) InlinabilityChecked() bool { return f.flags&funcInlinabilityChecked != 0 }
-func (f *Func) ExportInline() bool        { return f.flags&funcExportInline != 0 }
-func (f *Func) InstrumentBody() bool      { return f.flags&funcInstrumentBody != 0 }
+func (f *Func) Dupok() bool                    { return f.flags&funcDupok != 0 }
+func (f *Func) Wrapper() bool                  { return f.flags&funcWrapper != 0 }
+func (f *Func) Needctxt() bool                 { return f.flags&funcNeedctxt != 0 }
+func (f *Func) ReflectMethod() bool            { return f.flags&funcReflectMethod != 0 }
+func (f *Func) IsHiddenClosure() bool          { return f.flags&funcIsHiddenClosure != 0 }
+func (f *Func) HasDefer() bool                 { return f.flags&funcHasDefer != 0 }
+func (f *Func) NilCheckDisabled() bool         { return f.flags&funcNilCheckDisabled != 0 }
+func (f *Func) InlinabilityChecked() bool      { return f.flags&funcInlinabilityChecked != 0 }
+func (f *Func) ExportInline() bool             { return f.flags&funcExportInline != 0 }
+func (f *Func) InstrumentBody() bool           { return f.flags&funcInstrumentBody != 0 }
+func (f *Func) OpenCodedDeferDisallowed() bool { return f.flags&funcOpenCodedDeferDisallowed != 0 }
 
-func (f *Func) SetDupok(b bool)               { f.flags.set(funcDupok, b) }
-func (f *Func) SetWrapper(b bool)             { f.flags.set(funcWrapper, b) }
-func (f *Func) SetNeedctxt(b bool)            { f.flags.set(funcNeedctxt, b) }
-func (f *Func) SetReflectMethod(b bool)       { f.flags.set(funcReflectMethod, b) }
-func (f *Func) SetIsHiddenClosure(b bool)     { f.flags.set(funcIsHiddenClosure, b) }
-func (f *Func) SetHasDefer(b bool)            { f.flags.set(funcHasDefer, b) }
-func (f *Func) SetNilCheckDisabled(b bool)    { f.flags.set(funcNilCheckDisabled, b) }
-func (f *Func) SetInlinabilityChecked(b bool) { f.flags.set(funcInlinabilityChecked, b) }
-func (f *Func) SetExportInline(b bool)        { f.flags.set(funcExportInline, b) }
-func (f *Func) SetInstrumentBody(b bool)      { f.flags.set(funcInstrumentBody, b) }
+func (f *Func) SetDupok(b bool)                    { f.flags.set(funcDupok, b) }
+func (f *Func) SetWrapper(b bool)                  { f.flags.set(funcWrapper, b) }
+func (f *Func) SetNeedctxt(b bool)                 { f.flags.set(funcNeedctxt, b) }
+func (f *Func) SetReflectMethod(b bool)            { f.flags.set(funcReflectMethod, b) }
+func (f *Func) SetIsHiddenClosure(b bool)          { f.flags.set(funcIsHiddenClosure, b) }
+func (f *Func) SetHasDefer(b bool)                 { f.flags.set(funcHasDefer, b) }
+func (f *Func) SetNilCheckDisabled(b bool)         { f.flags.set(funcNilCheckDisabled, b) }
+func (f *Func) SetInlinabilityChecked(b bool)      { f.flags.set(funcInlinabilityChecked, b) }
+func (f *Func) SetExportInline(b bool)             { f.flags.set(funcExportInline, b) }
+func (f *Func) SetInstrumentBody(b bool)           { f.flags.set(funcInstrumentBody, b) }
+func (f *Func) SetOpenCodedDeferDisallowed(b bool) { f.flags.set(funcOpenCodedDeferDisallowed, b) }
 
 func (f *Func) setWBPos(pos src.XPos) {
 	if Debug_wb != 0 {
diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go
index 39d1ab689d..b064e7d71c 100644
--- a/src/cmd/compile/internal/gc/walk.go
+++ b/src/cmd/compile/internal/gc/walk.go
@@ -213,7 +213,6 @@ func walkstmt(n *Node) *Node {
 		yyerror("case statement out of place")
 
 	case ODEFER:
-		Curfn.Func.SetHasDefer(true)
 		fallthrough
 	case OGO:
 		switch n.Left.Op {
diff --git a/src/cmd/compile/internal/ssa/deadstore.go b/src/cmd/compile/internal/ssa/deadstore.go
index 6b9bcedadb..88af7a6f4a 100644
--- a/src/cmd/compile/internal/ssa/deadstore.go
+++ b/src/cmd/compile/internal/ssa/deadstore.go
@@ -170,6 +170,11 @@ func elimDeadAutosGeneric(f *Func) {
 			return
 		case OpVarLive:
 			// Don't delete the auto if it needs to be kept alive.
+
+			// We depend on this check to keep the autotmp stack slots
+			// for open-coded defers from being removed (since they
+			// may not be used by the inline code, but will be used by
+			// panic processing).
 			n, ok := v.Aux.(GCNode)
 			if !ok || n.StorageClass() != ClassAuto {
 				return
diff --git a/src/cmd/compile/internal/ssa/func.go b/src/cmd/compile/internal/ssa/func.go
index cdd5161913..332e201899 100644
--- a/src/cmd/compile/internal/ssa/func.go
+++ b/src/cmd/compile/internal/ssa/func.go
@@ -32,8 +32,16 @@ type Func struct {
 	Type   *types.Type // type signature of the function.
 	Blocks []*Block    // unordered set of all basic blocks (note: not indexable by ID)
 	Entry  *Block      // the entry basic block
-	bid    idAlloc     // block ID allocator
-	vid    idAlloc     // value ID allocator
+
+	// If we are using open-coded defers, this is the first call to a deferred
+	// function in the final defer exit sequence that we generated. This call
+	// should be after all defer statements, and will have all args, etc. of
+	// all defer calls as live. The liveness info of this call will be used
+	// for the deferreturn/ret segment generated for functions with open-coded
+	// defers.
+	LastDeferExit *Value
+	bid           idAlloc // block ID allocator
+	vid           idAlloc // value ID allocator
 
 	// Given an environment variable used for debug hash match,
 	// what file (if any) receives the yes/no logging?
diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go
index 1c101bfc27..468e9402ee 100644
--- a/src/cmd/internal/obj/link.go
+++ b/src/cmd/internal/obj/link.go
@@ -405,10 +405,11 @@ type FuncInfo struct {
 	dwarfAbsFnSym      *LSym
 	dwarfDebugLinesSym *LSym
 
-	GCArgs       *LSym
-	GCLocals     *LSym
-	GCRegs       *LSym
-	StackObjects *LSym
+	GCArgs             *LSym
+	GCLocals           *LSym
+	GCRegs             *LSym
+	StackObjects       *LSym
+	OpenCodedDeferInfo *LSym
 }
 
 type InlMark struct {
diff --git a/src/cmd/internal/objabi/funcdata.go b/src/cmd/internal/objabi/funcdata.go
index addbd2ac88..08b75eb9fe 100644
--- a/src/cmd/internal/objabi/funcdata.go
+++ b/src/cmd/internal/objabi/funcdata.go
@@ -15,11 +15,12 @@ const (
 	PCDATA_StackMapIndex = 1
 	PCDATA_InlTreeIndex  = 2
 
-	FUNCDATA_ArgsPointerMaps   = 0
-	FUNCDATA_LocalsPointerMaps = 1
-	FUNCDATA_RegPointerMaps    = 2
-	FUNCDATA_StackObjects      = 3
-	FUNCDATA_InlTree           = 4
+	FUNCDATA_ArgsPointerMaps    = 0
+	FUNCDATA_LocalsPointerMaps  = 1
+	FUNCDATA_RegPointerMaps     = 2
+	FUNCDATA_StackObjects       = 3
+	FUNCDATA_InlTree            = 4
+	FUNCDATA_OpenCodedDeferInfo = 5
 
 	// ArgsSizeUnknown is set in Func.argsize to mark all functions
 	// whose argument size is unknown (C vararg functions, and
diff --git a/src/cmd/internal/objabi/funcid.go b/src/cmd/internal/objabi/funcid.go
index c13c3cb458..487f009830 100644
--- a/src/cmd/internal/objabi/funcid.go
+++ b/src/cmd/internal/objabi/funcid.go
@@ -85,6 +85,12 @@ func GetFuncID(name, file string) FuncID {
 		return FuncID_panicwrap
 	case "runtime.handleAsyncEvent":
 		return FuncID_handleAsyncEvent
+	case "runtime.deferreturn":
+		// Don't show in the call stack (used when invoking defer functions)
+		return FuncID_wrapper
+	case "runtime.runOpenDeferFrame":
+		// Don't show in the call stack (used when invoking defer functions)
+		return FuncID_wrapper
 	}
 	if file == "<autogenerated>" {
 		return FuncID_wrapper
diff --git a/src/cmd/internal/objabi/stack.go b/src/cmd/internal/objabi/stack.go
index 62ab0398a6..7320dbf365 100644
--- a/src/cmd/internal/objabi/stack.go
+++ b/src/cmd/internal/objabi/stack.go
@@ -18,7 +18,7 @@ const (
 )
 
 // Initialize StackGuard and StackLimit according to target system.
-var StackGuard = 880*stackGuardMultiplier() + StackSystem
+var StackGuard = 896*stackGuardMultiplier() + StackSystem
 var StackLimit = StackGuard - StackSystem - StackSmall
 
 // stackGuardMultiplier returns a multiplier to apply to the default
diff --git a/src/cmd/link/internal/ld/pcln.go b/src/cmd/link/internal/ld/pcln.go
index d9904f9093..3d7b42b187 100644
--- a/src/cmd/link/internal/ld/pcln.go
+++ b/src/cmd/link/internal/ld/pcln.go
@@ -11,6 +11,7 @@ import (
 	"cmd/internal/sys"
 	"cmd/link/internal/sym"
 	"encoding/binary"
+	"fmt"
 	"log"
 	"os"
 	"path/filepath"
@@ -255,13 +256,23 @@ func (ctxt *Link) pclntab() {
 			}
 			if r.Type.IsDirectJump() && r.Sym != nil && r.Sym.Name == "runtime.deferreturn" {
 				if ctxt.Arch.Family == sys.Wasm {
-					deferreturn = lastWasmAddr
+					deferreturn = lastWasmAddr - 1
 				} else {
 					// Note: the relocation target is in the call instruction, but
 					// is not necessarily the whole instruction (for instance, on
 					// x86 the relocation applies to bytes [1:5] of the 5 byte call
 					// instruction).
 					deferreturn = uint32(r.Off)
+					switch ctxt.Arch.Family {
+					case sys.AMD64, sys.I386, sys.MIPS, sys.MIPS64, sys.RISCV64:
+						deferreturn--
+					case sys.PPC64, sys.ARM, sys.ARM64:
+						// no change
+					case sys.S390X:
+						deferreturn -= 2
+					default:
+						panic(fmt.Sprint("Unhandled architecture:", ctxt.Arch.Family))
+					}
 				}
 				break // only need one
 			}
diff --git a/src/cmd/link/internal/ld/symtab.go b/src/cmd/link/internal/ld/symtab.go
index d686a8a476..b4236a5239 100644
--- a/src/cmd/link/internal/ld/symtab.go
+++ b/src/cmd/link/internal/ld/symtab.go
@@ -498,7 +498,8 @@ func (ctxt *Link) symtab() {
 		case strings.HasPrefix(s.Name, "gcargs."),
 			strings.HasPrefix(s.Name, "gclocals."),
 			strings.HasPrefix(s.Name, "gclocals·"),
-			strings.HasPrefix(s.Name, "inltree."):
+			strings.HasPrefix(s.Name, "inltree."),
+			strings.HasSuffix(s.Name, ".opendefer"):
 			s.Type = sym.SGOFUNC
 			s.Attr |= sym.AttrNotInSymbolTable
 			s.Outer = symgofunc
diff --git a/src/runtime/callers_test.go b/src/runtime/callers_test.go
index fcfd10deff..cd1421ba91 100644
--- a/src/runtime/callers_test.go
+++ b/src/runtime/callers_test.go
@@ -5,6 +5,7 @@
 package runtime_test
 
 import (
+	"internal/race"
 	"reflect"
 	"runtime"
 	"strings"
@@ -12,19 +13,19 @@ import (
 )
 
 func f1(pan bool) []uintptr {
-	return f2(pan) // line 15
+	return f2(pan) // line 16
 }
 
 func f2(pan bool) []uintptr {
-	return f3(pan) // line 19
+	return f3(pan) // line 20
 }
 
 func f3(pan bool) []uintptr {
 	if pan {
-		panic("f3") // line 24
+		panic("f3") // line 25
 	}
 	ret := make([]uintptr, 20)
-	return ret[:runtime.Callers(0, ret)] // line 27
+	return ret[:runtime.Callers(0, ret)] // line 28
 }
 
 func testCallers(t *testing.T, pcs []uintptr, pan bool) {
@@ -48,16 +49,16 @@ func testCallers(t *testing.T, pcs []uintptr, pan bool) {
 
 	var f3Line int
 	if pan {
-		f3Line = 24
+		f3Line = 25
 	} else {
-		f3Line = 27
+		f3Line = 28
 	}
 	want := []struct {
 		name string
 		line int
 	}{
-		{"f1", 15},
-		{"f2", 19},
+		{"f1", 16},
+		{"f2", 20},
 		{"f3", f3Line},
 	}
 	for _, w := range want {
@@ -188,3 +189,36 @@ func TestCallersDivZeroPanic(t *testing.T) {
 		t.Fatal("did not see divide-by-sizer panic")
 	}
 }
+
+// This test will have a slightly different callstack if non-open-coded defers are
+// called (e.g. if race checks enabled), because of a difference in the way the
+// defer function is invoked.
+func TestCallersDeferNilFuncPanic(t *testing.T) {
+	if race.Enabled {
+		t.Skip("skipping TestCallersDeferNilFuncPanic under race detector")
+	}
+	// Make sure we don't have any extra frames on the stack (due to
+	// open-coded defer processing)
+	state := 1
+	want := []string{"runtime.Callers", "runtime_test.TestCallersDeferNilFuncPanic.func1",
+		"runtime.gopanic", "runtime.panicmem", "runtime.sigpanic",
+		"runtime_test.TestCallersDeferNilFuncPanic"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+		if state == 1 {
+			t.Fatal("nil defer func panicked at defer time rather than function exit time")
+		}
+
+	}()
+	var f func()
+	defer f()
+	// Use the value of 'state' to make sure nil defer func f causes panic at
+	// function exit, rather than at the defer statement.
+	state = 2
+}
diff --git a/src/runtime/defer_test.go b/src/runtime/defer_test.go
index 0d3e8e9d63..d830fc591f 100644
--- a/src/runtime/defer_test.go
+++ b/src/runtime/defer_test.go
@@ -15,11 +15,11 @@ import (
 // unconditional panic (hence no return from the function)
 func TestUnconditionalPanic(t *testing.T) {
 	defer func() {
-		if recover() == nil {
+		if recover() != "testUnconditional" {
 			t.Fatal("expected unconditional panic")
 		}
 	}()
-	panic("panic should be recovered")
+	panic("testUnconditional")
 }
 
 var glob int = 3
@@ -30,7 +30,7 @@ func TestOpenAndNonOpenDefers(t *testing.T) {
 	for {
 		// Non-open defer because in a loop
 		defer func(n int) {
-			if recover() == nil {
+			if recover() != "testNonOpenDefer" {
 				t.Fatal("expected testNonOpen panic")
 			}
 		}(3)
@@ -45,7 +45,7 @@ func TestOpenAndNonOpenDefers(t *testing.T) {
 //go:noinline
 func testOpen(t *testing.T, arg int) {
 	defer func(n int) {
-		if recover() == nil {
+		if recover() != "testOpenDefer" {
 			t.Fatal("expected testOpen panic")
 		}
 	}(4)
@@ -61,7 +61,7 @@ func TestNonOpenAndOpenDefers(t *testing.T) {
 	for {
 		// Non-open defer because in a loop
 		defer func(n int) {
-			if recover() == nil {
+			if recover() != "testNonOpenDefer" {
 				t.Fatal("expected testNonOpen panic")
 			}
 		}(3)
@@ -80,7 +80,7 @@ func TestConditionalDefers(t *testing.T) {
 	list = make([]int, 0, 10)
 
 	defer func() {
-		if recover() == nil {
+		if recover() != "testConditional" {
 			t.Fatal("expected panic")
 		}
 		want := []int{4, 2, 1}
@@ -106,7 +106,7 @@ func testConditionalDefers(n int) {
 			defer doappend(4)
 		}
 	}
-	panic("test")
+	panic("testConditional")
 }
 
 // Test that there is no compile-time or run-time error if an open-coded defer
@@ -174,3 +174,52 @@ func TestRecoverMatching(t *testing.T) {
 	}()
 	panic("panic1")
 }
+
+type nonSSAable [128]byte
+
+type bigStruct struct {
+	x, y, z, w, p, q int64
+}
+
+func mknonSSAable() nonSSAable {
+	globint1++
+	return nonSSAable{0, 0, 0, 0, 5}
+}
+
+var globint1, globint2 int
+
+//go:noinline
+func sideeffect(n int64) int64 {
+	globint2++
+	return n
+}
+
+// Test that nonSSAable arguments to defer are handled correctly and only evaluated once.
+func TestNonSSAableArgs(t *testing.T) {
+	globint1 = 0
+	globint2 = 0
+	var save1 byte
+	var save2 int64
+
+	defer func() {
+		if globint1 != 1 {
+			t.Fatal(fmt.Sprintf("globint1:  wanted: 1, got %v", globint1))
+		}
+		if save1 != 5 {
+			t.Fatal(fmt.Sprintf("save1:  wanted: 5, got %v", save1))
+		}
+		if globint2 != 1 {
+			t.Fatal(fmt.Sprintf("globint2:  wanted: 1, got %v", globint2))
+		}
+		if save2 != 2 {
+			t.Fatal(fmt.Sprintf("save2:  wanted: 2, got %v", save2))
+		}
+	}()
+
+	defer func(n nonSSAable) {
+		save1 = n[4]
+	}(mknonSSAable())
+	defer func(b bigStruct) {
+		save2 = b.y
+	}(bigStruct{1, 2, 3, 4, 5, sideeffect(6)})
+}
diff --git a/src/runtime/funcdata.h b/src/runtime/funcdata.h
index d9a35c51a0..0fb50ddfba 100644
--- a/src/runtime/funcdata.h
+++ b/src/runtime/funcdata.h
@@ -17,6 +17,7 @@
 #define FUNCDATA_RegPointerMaps 2
 #define FUNCDATA_StackObjects 3
 #define FUNCDATA_InlTree 4
+#define FUNCDATA_OpenCodedDeferInfo 5 /* info for func with open-coded defers */
 
 // Pseudo-assembly statements.
 
diff --git a/src/runtime/panic.go b/src/runtime/panic.go
index 5f33cd7c0c..291a660b3e 100644
--- a/src/runtime/panic.go
+++ b/src/runtime/panic.go
@@ -10,6 +10,19 @@ import (
 	"unsafe"
 )
 
+// We have two different ways of doing defers. The older way involves creating a
+// defer record at the time that a defer statement is executing and adding it to a
+// defer chain. This chain is inspected by the deferreturn call at all function
+// exits in order to run the appropriate defer calls. A cheaper way (which we call
+// open-coded defers) is used for functions in which no defer statements occur in
+// loops. In that case, we simply store the defer function/arg information into
+// specific stack slots at the point of each defer statement, as well as setting a
+// bit in a bitmask. At each function exit, we add inline code to directly make
+// the appropriate defer calls based on the bitmask and fn/arg information stored
+// on the stack. During panic/Goexit processing, the appropriate defer calls are
+// made using extra funcdata info that indicates the exact stack slots that
+// contain the bitmask and defer fn/args.
+
 // Check to make sure we can really generate a panic. If the panic
 // was generated from the runtime, or from inside malloc, then convert
 // to a throw of msg.
@@ -263,19 +276,24 @@ func deferprocStack(d *_defer) {
 	// are initialized here.
 	d.started = false
 	d.heap = false
+	d.openDefer = false
 	d.sp = getcallersp()
 	d.pc = getcallerpc()
+	d.framepc = 0
+	d.varp = 0
 	// The lines below implement:
 	//   d.panic = nil
+	//   d.fp = nil
 	//   d.link = gp._defer
 	//   gp._defer = d
-	// But without write barriers. The first two are writes to
+	// But without write barriers. The first three are writes to
 	// the stack so they don't need a write barrier, and furthermore
 	// are to uninitialized memory, so they must not use a write barrier.
-	// The third write does not require a write barrier because we
+	// The fourth write does not require a write barrier because we
 	// explicitly mark all the defer structures, so we don't need to
 	// keep track of pointers to them with a write barrier.
 	*(*uintptr)(unsafe.Pointer(&d._panic)) = 0
+	*(*uintptr)(unsafe.Pointer(&d.fd)) = 0
 	*(*uintptr)(unsafe.Pointer(&d.link)) = uintptr(unsafe.Pointer(gp._defer))
 	*(*uintptr)(unsafe.Pointer(&gp._defer)) = uintptr(unsafe.Pointer(d))
 
@@ -463,8 +481,12 @@ func freedefer(d *_defer) {
 	// started causing a nosplit stack overflow via typedmemmove.
 	d.siz = 0
 	d.started = false
+	d.openDefer = false
 	d.sp = 0
 	d.pc = 0
+	d.framepc = 0
+	d.varp = 0
+	d.fd = nil
 	// d._panic and d.fn must be nil already.
 	// If not, we would have called freedeferpanic or freedeferfn above,
 	// both of which throw.
@@ -493,9 +515,11 @@ func freedeferfn() {
 // to have been called by the caller of deferreturn at the point
 // just before deferreturn was called. The effect is that deferreturn
 // is called again and again until there are no more deferred functions.
-// Cannot split the stack because we reuse the caller's frame to
-// call the deferred function.
-
+//
+// Declared as nosplit, because the function should not be preempted once we start
+// modifying the caller's frame in order to reuse the frame to call the deferred
+// function.
+//
 // The single argument isn't actually used - it just has its address
 // taken so it can be matched against pending defers.
 //go:nosplit
@@ -509,6 +533,15 @@ func deferreturn(arg0 uintptr) {
 	if d.sp != sp {
 		return
 	}
+	if d.openDefer {
+		done := runOpenDeferFrame(gp, d)
+		if !done {
+			throw("unfinished open-coded defers in deferreturn")
+		}
+		gp._defer = d.link
+		freedefer(d)
+		return
+	}
 
 	// Moving arguments around.
 	//
@@ -544,6 +577,8 @@ func Goexit() {
 	// This code is similar to gopanic, see that implementation
 	// for detailed comments.
 	gp := getg()
+	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
+
 	for {
 		d := gp._defer
 		if d == nil {
@@ -554,13 +589,26 @@ func Goexit() {
 				d._panic.aborted = true
 				d._panic = nil
 			}
-			d.fn = nil
-			gp._defer = d.link
-			freedefer(d)
-			continue
+			if !d.openDefer {
+				d.fn = nil
+				gp._defer = d.link
+				freedefer(d)
+				continue
+			}
 		}
 		d.started = true
-		reflectcall(nil, unsafe.Pointer(d.fn), deferArgs(d), uint32(d.siz), uint32(d.siz))
+		if d.openDefer {
+			done := runOpenDeferFrame(gp, d)
+			if !done {
+				// We should always run all defers in the frame,
+				// since there is no panic associated with this
+				// defer that can be recovered.
+				throw("unfinished open-coded defers in Goexit")
+			}
+			addOneOpenDeferFrame(gp, 0, nil)
+		} else {
+			reflectcall(nil, unsafe.Pointer(d.fn), deferArgs(d), uint32(d.siz), uint32(d.siz))
+		}
 		if gp._defer != d {
 			throw("bad defer entry in Goexit")
 		}
@@ -607,6 +655,182 @@ func printpanics(p *_panic) {
 	print("\n")
 }
 
+// addOneOpenDeferFrame scans the stack for the first frame (if any) with
+// open-coded defers and if it finds one, adds a single record to the defer chain
+// for that frame. If sp is non-nil, it starts the stack scan from the frame
+// specified by sp. If sp is nil, it uses the sp from the current defer record
+// (which has just been finished). Hence, it continues the stack scan from the
+// frame of the defer that just finished. It skips any frame that already has an
+// open-coded _defer record, which would have been been created from a previous
+// (unrecovered) panic.
+//
+// Note: All entries of the defer chain (including this new open-coded entry) have
+// their pointers (including sp) adjusted properly if the stack moves while
+// running deferred functions. Also, it is safe to pass in the sp arg (which is
+// the direct result of calling getcallersp()), because all pointer variables
+// (including arguments) are adjusted as needed during stack copies.
+func addOneOpenDeferFrame(gp *g, pc uintptr, sp unsafe.Pointer) {
+	var prevDefer *_defer
+	if sp == nil {
+		prevDefer = gp._defer
+		pc = prevDefer.framepc
+		sp = unsafe.Pointer(prevDefer.sp)
+	}
+	systemstack(func() {
+		gentraceback(pc, uintptr(sp), 0, gp, 0, nil, 0x7fffffff,
+			func(frame *stkframe, unused unsafe.Pointer) bool {
+				if prevDefer != nil && prevDefer.sp == frame.sp {
+					// Skip the frame for the previous defer that
+					// we just finished (and was used to set
+					// where we restarted the stack scan)
+					return true
+				}
+				f := frame.fn
+				fd := funcdata(f, _FUNCDATA_OpenCodedDeferInfo)
+				if fd == nil {
+					return true
+				}
+				// Insert the open defer record in the
+				// chain, in order sorted by sp.
+				d := gp._defer
+				var prev *_defer
+				for d != nil {
+					dsp := d.sp
+					if frame.sp < dsp {
+						break
+					}
+					if frame.sp == dsp {
+						if !d.openDefer {
+							throw("duplicated defer entry")
+						}
+						return true
+					}
+					prev = d
+					d = d.link
+				}
+				if frame.fn.deferreturn == 0 {
+					throw("missing deferreturn")
+				}
+
+				maxargsize, _ := readvarintUnsafe(fd)
+				d1 := newdefer(int32(maxargsize))
+				d1.openDefer = true
+				d1._panic = nil
+				// These are the pc/sp to set after we've
+				// run a defer in this frame that did a
+				// recover. We return to a special
+				// deferreturn that runs any remaining
+				// defers and then returns from the
+				// function.
+				d1.pc = frame.fn.entry + uintptr(frame.fn.deferreturn)
+				d1.varp = frame.varp
+				d1.fd = fd
+				// Save the SP/PC associated with current frame,
+				// so we can continue stack trace later if needed.
+				d1.framepc = frame.pc
+				d1.sp = frame.sp
+				d1.link = d
+				if prev == nil {
+					gp._defer = d1
+				} else {
+					prev.link = d1
+				}
+				// Stop stack scanning after adding one open defer record
+				return false
+			},
+			nil, 0)
+	})
+}
+
+// readvarintUnsafe reads the uint32 in varint format starting at fd, and returns the
+// uint32 and a pointer to the byte following the varint.
+//
+// There is a similar function runtime.readvarint, which takes a slice of bytes,
+// rather than an unsafe pointer. These functions are duplicated, because one of
+// the two use cases for the functions would get slower if the functions were
+// combined.
+func readvarintUnsafe(fd unsafe.Pointer) (uint32, unsafe.Pointer) {
+	var r uint32
+	var shift int
+	for {
+		b := *(*uint8)((unsafe.Pointer(fd)))
+		fd = add(fd, unsafe.Sizeof(b))
+		if b < 128 {
+			return r + uint32(b)<<shift, fd
+		}
+		r += ((uint32(b) &^ 128) << shift)
+		shift += 7
+		if shift > 28 {
+			panic("Bad varint")
+		}
+	}
+}
+
+// runOpenDeferFrame runs the active open-coded defers in the frame specified by
+// d. It normally processes all active defers in the frame, but stops immediately
+// if a defer does a successful recover. It returns true if there are no
+// remaining defers to run in the frame.
+func runOpenDeferFrame(gp *g, d *_defer) bool {
+	done := true
+	fd := d.fd
+
+	// Skip the maxargsize
+	_, fd = readvarintUnsafe(fd)
+	deferBitsOffset, fd := readvarintUnsafe(fd)
+	nDefers, fd := readvarintUnsafe(fd)
+	deferBits := *(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset)))
+
+	for i := int(nDefers) - 1; i >= 0; i-- {
+		// read the funcdata info for this defer
+		var argWidth, closureOffset, hasRcvrOffset, rcvrOffset, nArgs uint32
+		argWidth, fd = readvarintUnsafe(fd)
+		closureOffset, fd = readvarintUnsafe(fd)
+		hasRcvrOffset, fd = readvarintUnsafe(fd)
+		if hasRcvrOffset > 0 {
+			rcvrOffset, fd = readvarintUnsafe(fd)
+		}
+		nArgs, fd = readvarintUnsafe(fd)
+		if deferBits&(1<<i) == 0 {
+			for j := uint32(0); j < nArgs; j++ {
+				_, fd = readvarintUnsafe(fd)
+				_, fd = readvarintUnsafe(fd)
+				_, fd = readvarintUnsafe(fd)
+			}
+			continue
+		}
+		closure := *(**funcval)(unsafe.Pointer(d.varp - uintptr(closureOffset)))
+		d.fn = closure
+		deferArgs := deferArgs(d)
+		if hasRcvrOffset > 0 {
+			*(*unsafe.Pointer)(deferArgs) = *(*unsafe.Pointer)((unsafe.Pointer)((d.varp - uintptr(rcvrOffset))))
+		}
+		for j := uint32(0); j < nArgs; j++ {
+			var argOffset, argLen, argCallOffset uint32
+			argOffset, fd = readvarintUnsafe(fd)
+			argLen, fd = readvarintUnsafe(fd)
+			argCallOffset, fd = readvarintUnsafe(fd)
+			memmove(unsafe.Pointer(uintptr(deferArgs)+uintptr(argCallOffset)),
+				unsafe.Pointer(d.varp-uintptr(argOffset)),
+				uintptr(argLen))
+		}
+		deferBits = deferBits &^ (1 << i)
+		*(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset))) = deferBits
+		if d._panic != nil {
+			d._panic.argp = unsafe.Pointer(getargp(0))
+		}
+		reflectcall(nil, unsafe.Pointer(closure), deferArgs, argWidth, argWidth)
+		d.fn = nil
+		// These args are just a copy, so can be cleared immediately
+		memclrNoHeapPointers(deferArgs, uintptr(argWidth))
+		if d._panic != nil && d._panic.recovered {
+			done = deferBits == 0
+			break
+		}
+	}
+
+	return done
+}
+
 // The implementation of the predeclared function panic.
 func gopanic(e interface{}) {
 	gp := getg()
@@ -646,6 +870,10 @@ func gopanic(e interface{}) {
 
 	atomic.Xadd(&runningPanicDefers, 1)
 
+	// By calculating getcallerpc/getcallersp here, we avoid scanning the
+	// gopanic frame (stack scanning is slow...)
+	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
+
 	for {
 		d := gp._defer
 		if d == nil {
@@ -659,10 +887,16 @@ func gopanic(e interface{}) {
 				d._panic.aborted = true
 			}
 			d._panic = nil
-			d.fn = nil
-			gp._defer = d.link
-			freedefer(d)
-			continue
+			if !d.openDefer {
+				// For open-coded defers, we need to process the
+				// defer again, in case there are any other defers
+				// to call in the frame (not including the defer
+				// call that caused the panic).
+				d.fn = nil
+				gp._defer = d.link
+				freedefer(d)
+				continue
+			}
 		}
 
 		// Mark defer as started, but keep on list, so that traceback
@@ -675,8 +909,16 @@ func gopanic(e interface{}) {
 		// will find d in the list and will mark d._panic (this panic) aborted.
 		d._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
 
-		p.argp = unsafe.Pointer(getargp(0))
-		reflectcall(nil, unsafe.Pointer(d.fn), deferArgs(d), uint32(d.siz), uint32(d.siz))
+		done := true
+		if d.openDefer {
+			done = runOpenDeferFrame(gp, d)
+			if done && !d._panic.recovered {
+				addOneOpenDeferFrame(gp, 0, nil)
+			}
+		} else {
+			p.argp = unsafe.Pointer(getargp(0))
+			reflectcall(nil, unsafe.Pointer(d.fn), deferArgs(d), uint32(d.siz), uint32(d.siz))
+		}
 		p.argp = nil
 
 		// reflectcall did not panic. Remove d.
@@ -684,18 +926,52 @@ func gopanic(e interface{}) {
 			throw("bad defer entry in panic")
 		}
 		d._panic = nil
-		d.fn = nil
-		gp._defer = d.link
 
 		// trigger shrinkage to test stack copy. See stack_test.go:TestStackPanic
 		//GC()
 
 		pc := d.pc
 		sp := unsafe.Pointer(d.sp) // must be pointer so it gets adjusted during stack copy
-		freedefer(d)
+		if done {
+			d.fn = nil
+			gp._defer = d.link
+			freedefer(d)
+		}
 		if p.recovered {
 			atomic.Xadd(&runningPanicDefers, -1)
 
+			if done {
+				// Remove any remaining non-started, open-coded defer
+				// entry after a recover (there's at most one, if we just
+				// ran a non-open-coded defer), since the entry will
+				// become out-dated and the defer will be executed
+				// normally.
+				d := gp._defer
+				var prev *_defer
+				for d != nil {
+					if d.openDefer {
+						if d.started {
+							// This defer is started but we
+							// are in the middle of a
+							// defer-panic-recover inside of
+							// it, so don't remove it or any
+							// further defer entries
+							break
+						}
+						if prev == nil {
+							gp._defer = d.link
+						} else {
+							prev.link = d.link
+						}
+						freedefer(d)
+						break
+					} else {
+						prev = d
+						d = d.link
+					}
+				}
+			}
+
 			gp._panic = p.link
 			// Aborted panics are marked but remain on the g.panic list.
 			// Remove them from the list.
@@ -803,7 +1079,7 @@ func recovery(gp *g) {
 	}
 
 	// Make the deferproc for this d return again,
-	// this time returning 1.  The calling function will
+	// this time returning 1. The calling function will
 	// jump to the standard return epilogue.
 	gp.sched.sp = sp
 	gp.sched.pc = pc
diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go
index dd399e00a6..20813d09eb 100644
--- a/src/runtime/runtime2.go
+++ b/src/runtime/runtime2.go
@@ -701,7 +701,7 @@ type _func struct {
 	nameoff int32   // function name
 
 	args        int32  // in/out args size
-	deferreturn uint32 // offset of a deferreturn block from entry, if any.
+	deferreturn uint32 // offset of start of a deferreturn call instruction from entry, if any.
 
 	pcsp      int32
 	pcfile    int32
@@ -774,7 +774,7 @@ func extendRandom(r []byte, n int) {
 }
 
 // A _defer holds an entry on the list of deferred calls.
-// If you add a field here, add code to clear it in freedefer.
+// If you add a field here, add code to clear it in freedefer and deferProcStack
 // This struct must match the code in cmd/compile/internal/gc/reflect.go:deferstruct
 // and cmd/compile/internal/gc/ssa.go:(*state).call.
 // Some defers will be allocated on the stack and some on the heap.
@@ -785,11 +785,27 @@ type _defer struct {
 	siz     int32 // includes both arguments and results
 	started bool
 	heap    bool
-	sp      uintptr // sp at time of defer
-	pc      uintptr
-	fn      *funcval
-	_panic  *_panic // panic that is running defer
-	link    *_defer
+	// openDefer indicates that this _defer is for a frame with open-coded
+	// defers. We have only one defer record for the entire frame (which may
+	// currently have 0, 1, or more defers active).
+	openDefer bool
+	sp        uintptr // sp at time of defer
+	pc        uintptr // pc at time of defer
+	fn        *funcval
+	_panic    *_panic // panic that is running defer
+	link      *_defer
+
+	// If openDefer is true, the fields below record values about the stack
+	// frame and associated function that has the open-coded defer(s). sp
+	// above will be the sp for the frame, and pc will be address of the
+	// deferreturn call in the function.
+	fd   unsafe.Pointer // funcdata for the function associated with the frame
+	varp uintptr        // value of varp for the stack frame
+	// framepc is the current pc associated with the stack frame. Together,
+	// with sp above (which is the sp associated with the stack frame),
+	// framepc/sp can be used as pc/sp pair to continue a stack trace via
+	// gentraceback().
+	framepc uintptr
 }
 
 // A _panic holds information about an active panic.
diff --git a/src/runtime/runtime_test.go b/src/runtime/runtime_test.go
index ab7a03b2d1..a1946d3fcb 100644
--- a/src/runtime/runtime_test.go
+++ b/src/runtime/runtime_test.go
@@ -89,7 +89,7 @@ func BenchmarkDefer(b *testing.B) {
 }
 
 func defer1() {
-	defer func(x, y, z int) {
+	func(x, y, z int) {
 		if recover() != nil || x != 1 || y != 2 || z != 3 {
 			panic("bad recover")
 		}
diff --git a/src/runtime/stack.go b/src/runtime/stack.go
index 271b24c58a..d72582e82e 100644
--- a/src/runtime/stack.go
+++ b/src/runtime/stack.go
@@ -91,7 +91,7 @@ const (
 
 	// The stack guard is a pointer this many bytes above the
 	// bottom of the stack.
-	_StackGuard = 880*sys.StackGuardMultiplier + _StackSystem
+	_StackGuard = 896*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
@@ -736,6 +736,8 @@ func adjustdefers(gp *g, adjinfo *adjustinfo) {
 		adjustpointer(adjinfo, unsafe.Pointer(&d.sp))
 		adjustpointer(adjinfo, unsafe.Pointer(&d._panic))
 		adjustpointer(adjinfo, unsafe.Pointer(&d.link))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.varp))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.fd))
 	}
 
 	// Adjust defer argument blocks the same way we adjust active stack frames.
diff --git a/src/runtime/symtab.go b/src/runtime/symtab.go
index df6e02f62a..e99b8cf669 100644
--- a/src/runtime/symtab.go
+++ b/src/runtime/symtab.go
@@ -216,11 +216,12 @@ const (
 	_PCDATA_StackMapIndex = 1
 	_PCDATA_InlTreeIndex  = 2
 
-	_FUNCDATA_ArgsPointerMaps   = 0
-	_FUNCDATA_LocalsPointerMaps = 1
-	_FUNCDATA_RegPointerMaps    = 2
-	_FUNCDATA_StackObjects      = 3
-	_FUNCDATA_InlTree           = 4
+	_FUNCDATA_ArgsPointerMaps    = 0
+	_FUNCDATA_LocalsPointerMaps  = 1
+	_FUNCDATA_RegPointerMaps     = 2
+	_FUNCDATA_StackObjects       = 3
+	_FUNCDATA_InlTree            = 4
+	_FUNCDATA_OpenCodedDeferInfo = 5
 
 	_ArgsSizeUnknown = -0x80000000
 )
diff --git a/test/defererrcheck.go b/test/defererrcheck.go
new file mode 100644
index 0000000000..5b90e58738
--- /dev/null
+++ b/test/defererrcheck.go
@@ -0,0 +1,86 @@
+// errorcheck -0 -l -d=defer
+
+// Copyright 2019 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.
+
+// check that open-coded defers are used in expected situations
+
+package main
+
+import "fmt"
+
+var glob = 3
+
+func f1() {
+
+	for i := 0; i < 10; i++ {
+		fmt.Println("loop")
+	}
+	defer func() { // ERROR "open-coded defer in function f1"
+		fmt.Println("defer")
+	}()
+}
+
+func f2() {
+	for {
+		defer func() { // ERROR "heap-allocated defer in function f2"
+			fmt.Println("defer1")
+		}()
+		if glob > 2 {
+			break
+		}
+	}
+	defer func() { // ERROR "stack-allocated defer in function f2"
+		fmt.Println("defer2")
+	}()
+}
+
+func f3() {
+	defer func() { // ERROR "stack-allocated defer in function f3"
+		fmt.Println("defer2")
+	}()
+	for {
+		defer func() { // ERROR "heap-allocated defer in function f3"
+			fmt.Println("defer1")
+		}()
+		if glob > 2 {
+			break
+		}
+	}
+}
+
+func f4() {
+	defer func() { // ERROR "open-coded defer in function f4"
+		fmt.Println("defer")
+	}()
+label:
+	fmt.Println("goto loop")
+	if glob > 2 {
+		goto label
+	}
+}
+
+func f5() {
+label:
+	fmt.Println("goto loop")
+	defer func() { // ERROR "heap-allocated defer in function f5"
+		fmt.Println("defer")
+	}()
+	if glob > 2 {
+		goto label
+	}
+}
+
+func f6() {
+label:
+	fmt.Println("goto loop")
+	if glob > 2 {
+		goto label
+	}
+	// The current analysis doesn't end a backward goto loop, so this defer is
+	// considered to be inside a loop
+	defer func() { // ERROR "heap-allocated defer in function f6"
+		fmt.Println("defer")
+	}()
+}
diff --git a/test/live.go b/test/live.go
index b6e6d93f5f..32c397f4a9 100644
--- a/test/live.go
+++ b/test/live.go
@@ -367,16 +367,19 @@ func f24() {
 	m2[[2]string{"x", "y"}] = nil
 }
 
-// defer should not cause spurious ambiguously live variables
-
+// Non-open-coded defers should not cause autotmps.  (Open-coded defers do create extra autotmps).
 func f25(b bool) {
-	defer g25()
+	for i := 0; i < 2; i++ {
+		// Put in loop to make sure defer is not open-coded
+		defer g25()
+	}
 	if b {
 		return
 	}
 	var x string
 	x = g14()
 	printstring(x)
+	return
 }
 
 func g25()
@@ -417,7 +420,8 @@ func f27defer(b bool) {
 		defer call27(func() { x++ }) // ERROR "stack object .autotmp_[0-9]+ struct \{"
 	}
 	defer call27(func() { x++ }) // ERROR "stack object .autotmp_[0-9]+ struct \{"
-	printnl()
+	printnl()                    // ERROR "live at call to printnl: .autotmp_[0-9]+ .autotmp_[0-9]+"
+	return                       // ERROR "live at call to call27: .autotmp_[0-9]+"
 }
 
 // and newproc (go) escapes to the heap
@@ -687,12 +691,12 @@ type R struct{ *T } // ERRORAUTO "live at entry to \(\*R\)\.Foo: \.this ptr" "li
 // In particular, at printint r must be live.
 func f41(p, q *int) (r *int) { // ERROR "live at entry to f41: p q$"
 	r = p
-	defer func() { // ERROR "live at call to deferprocStack: q r$" "live at call to deferreturn: r$"
+	defer func() {
 		recover()
 	}()
-	printint(0) // ERROR "live at call to printint: q r$"
+	printint(0) // ERROR "live at call to printint: q r .autotmp_[0-9]+$"
 	r = q
-	return // ERROR "live at call to deferreturn: r$"
+	return // ERROR "live at call to f41.func1: r .autotmp_[0-9]+$"
 }
 
 func f42() {
diff --git a/test/nosplit.go b/test/nosplit.go
index 266e6077b1..3b7e605999 100644
--- a/test/nosplit.go
+++ b/test/nosplit.go
@@ -309,17 +309,17 @@ TestCases:
 				name := m[1]
 				size, _ := strconv.Atoi(m[2])
 
-				// The limit was originally 128 but is now 752 (880-128).
+				// The limit was originally 128 but is now 768 (896-128).
 				// Instead of rewriting the test cases above, adjust
 				// the first stack frame to use up the extra bytes.
 				if i == 0 {
-					size += (880 - 128) - 128
+					size += (896 - 128) - 128
 					// Noopt builds have a larger stackguard.
 					// See ../src/cmd/dist/buildruntime.go:stackGuardMultiplier
 					// This increase is included in objabi.StackGuard
 					for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") {
 						if s == "-N" {
-							size += 880
+							size += 896
 						}
 					}
 				}