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cmd/compile: better check for single live memory

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Enhance the one-live-memory-at-a-time check to run during many
more phases of the SSA backend. Also make it work in an interblock
fashion.

Change types.IsMemory to return true for tuples containing a memory type.

Fix trim pass to build the merged phi correctly. Doesn't affect
code but allows the check to pass after trim runs.

Switch the AddTuple* ops to take the memory-containing tuple argument second.

Update #20335

Change-Id: I5b03ef3606b75a9e4f765276bb8b183cdc172b43
Reviewed-on: https://go-review.googlesource.com/43495
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This commit is contained in:
Keith Randall 2017-05-15 09:00:55 -07:00
parent d5e01c044f
commit 256210c719
13 changed files with 192 additions and 97 deletions
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132
src/cmd/compile/internal/ssa/check.go
View File

@ -310,6 +310,10 @@ func checkFunc(f *Func) {
}
}
memCheck(f)
}
func memCheck(f *Func) {
// Check that if a tuple has a memory type, it is second.
for _, b := range f.Blocks {
for _, v := range b.Values {
@ -319,24 +323,122 @@ func checkFunc(f *Func) {
}
}
// Check that only one memory is live at any point.
// TODO: make this check examine interblock.
if f.scheduled {
for _, b := range f.Blocks {
var mem *Value // the live memory
// Single live memory checks.
// These checks only work if there are no memory copies.
// (Memory copies introduce ambiguity about which mem value is really live.
// probably fixable, but it's easier to avoid the problem.)
// For the same reason, disable this check if some memory ops are unused.
for _, b := range f.Blocks {
for _, v := range b.Values {
if (v.Op == OpCopy || v.Uses == 0) && v.Type.IsMemory() {
return
}
}
if b != f.Entry && len(b.Preds) == 0 {
return
}
}
// Compute live memory at the end of each block.
lastmem := make([]*Value, f.NumBlocks())
ss := newSparseSet(f.NumValues())
for _, b := range f.Blocks {
// Mark overwritten memory values. Those are args of other
// ops that generate memory values.
ss.clear()
for _, v := range b.Values {
if v.Op == OpPhi || !v.Type.IsMemory() {
continue
}
if m := v.MemoryArg(); m != nil {
ss.add(m.ID)
}
}
// There should be at most one remaining unoverwritten memory value.
for _, v := range b.Values {
if !v.Type.IsMemory() {
continue
}
if ss.contains(v.ID) {
continue
}
if lastmem[b.ID] != nil {
f.Fatalf("two live memory values in %s: %s and %s", b, lastmem[b.ID], v)
}
lastmem[b.ID] = v
}
// If there is no remaining memory value, that means there was no memory update.
// Take any memory arg.
if lastmem[b.ID] == nil {
for _, v := range b.Values {
if v.Op != OpPhi {
for _, a := range v.Args {
if a.Type.IsMemory() || a.Type.IsTuple() && a.Type.FieldType(1).IsMemory() {
if mem == nil {
mem = a
} else if mem != a {
f.Fatalf("two live mems @ %s: %s and %s", v, mem, a)
}
}
if v.Op == OpPhi {
continue
}
m := v.MemoryArg()
if m == nil {
continue
}
if lastmem[b.ID] != nil && lastmem[b.ID] != m {
f.Fatalf("two live memory values in %s: %s and %s", b, lastmem[b.ID], m)
}
lastmem[b.ID] = m
}
}
}
// Propagate last live memory through storeless blocks.
for {
changed := false
for _, b := range f.Blocks {
if lastmem[b.ID] != nil {
continue
}
for _, e := range b.Preds {
p := e.b
if lastmem[p.ID] != nil {
lastmem[b.ID] = lastmem[p.ID]
changed = true
break
}
}
}
if !changed {
break
}
}
// Check merge points.
for _, b := range f.Blocks {
for _, v := range b.Values {
if v.Op == OpPhi && v.Type.IsMemory() {
for i, a := range v.Args {
if a != lastmem[b.Preds[i].b.ID] {
f.Fatalf("inconsistent memory phi %s %d %s %s", v.LongString(), i, a, lastmem[b.Preds[i].b.ID])
}
}
if v.Type.IsMemory() || v.Type.IsTuple() && v.Type.FieldType(1).IsMemory() {
}
}
}
// Check that only one memory is live at any point.
if f.scheduled {
for _, b := range f.Blocks {
var mem *Value // the current live memory in the block
for _, v := range b.Values {
if v.Op == OpPhi {
if v.Type.IsMemory() {
mem = v
}
continue
}
if mem == nil && len(b.Preds) > 0 {
// If no mem phi, take mem of any predecessor.
mem = lastmem[b.Preds[0].b.ID]
}
for _, a := range v.Args {
if a.Type.IsMemory() && a != mem {
f.Fatalf("two live mems @ %s: %s and %s", v, mem, a)
}
}
if v.Type.IsMemory() {
mem = v
}
}

4
src/cmd/compile/internal/ssa/deadstore.go
View File

@ -34,10 +34,6 @@ func dse(f *Func) {
}
if v.Type.IsMemory() {
stores = append(stores, v)
if v.Op == OpSelect1 {
// Use the args of the tuple-generating op.
v = v.Args[0]
}
for _, a := range v.Args {
if a.Block == b && a.Type.IsMemory() {
storeUse.add(a.ID)

12
src/cmd/compile/internal/ssa/gen/AMD64.rules
View File

@ -487,12 +487,12 @@
(AtomicExchange64 ptr val mem) -> (XCHGQ val ptr mem)
// Atomic adds.
(AtomicAdd32 ptr val mem) -> (AddTupleFirst32 (XADDLlock val ptr mem) val)
(AtomicAdd64 ptr val mem) -> (AddTupleFirst64 (XADDQlock val ptr mem) val)
(Select0 <t> (AddTupleFirst32 tuple val)) -> (ADDL val (Select0 <t> tuple))
(Select1 (AddTupleFirst32 tuple _ )) -> (Select1 tuple)
(Select0 <t> (AddTupleFirst64 tuple val)) -> (ADDQ val (Select0 <t> tuple))
(Select1 (AddTupleFirst64 tuple _ )) -> (Select1 tuple)
(AtomicAdd32 ptr val mem) -> (AddTupleFirst32 val (XADDLlock val ptr mem))
(AtomicAdd64 ptr val mem) -> (AddTupleFirst64 val (XADDQlock val ptr mem))
(Select0 <t> (AddTupleFirst32 val tuple)) -> (ADDL val (Select0 <t> tuple))
(Select1 (AddTupleFirst32 _ tuple)) -> (Select1 tuple)
(Select0 <t> (AddTupleFirst64 val tuple)) -> (ADDQ val (Select0 <t> tuple))
(Select1 (AddTupleFirst64 _ tuple)) -> (Select1 tuple)
// Atomic compare and swap.
(AtomicCompareAndSwap32 ptr old new_ mem) -> (CMPXCHGLlock ptr old new_ mem)

4
src/cmd/compile/internal/ssa/gen/AMD64Ops.go
View File

@ -572,8 +572,8 @@ func init() {
// Note: arg0 and arg1 are backwards compared to MOVLstore (to facilitate resultInArg0)!
{name: "XADDLlock", argLength: 3, reg: gpstorexchg, asm: "XADDL", typ: "(UInt32,Mem)", aux: "SymOff", resultInArg0: true, clobberFlags: true, faultOnNilArg1: true, hasSideEffects: true, symEffect: "RdWr"},
{name: "XADDQlock", argLength: 3, reg: gpstorexchg, asm: "XADDQ", typ: "(UInt64,Mem)", aux: "SymOff", resultInArg0: true, clobberFlags: true, faultOnNilArg1: true, hasSideEffects: true, symEffect: "RdWr"},
{name: "AddTupleFirst32", argLength: 2}, // arg0=tuple <x,y>. Returns <x+arg1,y>.
{name: "AddTupleFirst64", argLength: 2}, // arg0=tuple <x,y>. Returns <x+arg1,y>.
{name: "AddTupleFirst32", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>.
{name: "AddTupleFirst64", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>.
// Compare and swap.
// arg0 = pointer, arg1 = old value, arg2 = new value, arg3 = memory.

12
src/cmd/compile/internal/ssa/gen/S390X.rules
View File

@ -120,12 +120,12 @@
(AtomicStorePtrNoWB ptr val mem) -> (MOVDatomicstore ptr val mem)
// Atomic adds.
(AtomicAdd32 ptr val mem) -> (AddTupleFirst32 (LAA ptr val mem) val)
(AtomicAdd64 ptr val mem) -> (AddTupleFirst64 (LAAG ptr val mem) val)
(Select0 <t> (AddTupleFirst32 tuple val)) -> (ADDW val (Select0 <t> tuple))
(Select1 (AddTupleFirst32 tuple _ )) -> (Select1 tuple)
(Select0 <t> (AddTupleFirst64 tuple val)) -> (ADD val (Select0 <t> tuple))
(Select1 (AddTupleFirst64 tuple _ )) -> (Select1 tuple)
(AtomicAdd32 ptr val mem) -> (AddTupleFirst32 val (LAA ptr val mem))
(AtomicAdd64 ptr val mem) -> (AddTupleFirst64 val (LAAG ptr val mem))
(Select0 <t> (AddTupleFirst32 val tuple)) -> (ADDW val (Select0 <t> tuple))
(Select1 (AddTupleFirst32 _ tuple)) -> (Select1 tuple)
(Select0 <t> (AddTupleFirst64 val tuple)) -> (ADD val (Select0 <t> tuple))
(Select1 (AddTupleFirst64 _ tuple)) -> (Select1 tuple)
// Atomic exchanges.
(AtomicExchange32 ptr val mem) -> (LoweredAtomicExchange32 ptr val mem)

4
src/cmd/compile/internal/ssa/gen/S390XOps.go
View File

@ -467,8 +467,8 @@ func init() {
// Returns a tuple of <old contents of *(arg0+auxint+aux), memory>.
{name: "LAA", argLength: 3, reg: gpstorelaa, asm: "LAA", typ: "(UInt32,Mem)", aux: "SymOff", faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"},
{name: "LAAG", argLength: 3, reg: gpstorelaa, asm: "LAAG", typ: "(UInt64,Mem)", aux: "SymOff", faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"},
{name: "AddTupleFirst32", argLength: 2}, // arg0=tuple <x,y>. Returns <x+arg1,y>.
{name: "AddTupleFirst64", argLength: 2}, // arg0=tuple <x,y>. Returns <x+arg1,y>.
{name: "AddTupleFirst32", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>.
{name: "AddTupleFirst64", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>.
// Compare and swap.
// arg0 = pointer, arg1 = old value, arg2 = new value, arg3 = memory.

4
src/cmd/compile/internal/ssa/loopreschedchecks.go
View File

@ -391,10 +391,6 @@ func findLastMems(f *Func) []*Value {
}
if v.Type.IsMemory() {
stores = append(stores, v)
if v.Op == OpSelect1 {
// Use the arg of the tuple-generating op.
v = v.Args[0]
}
for _, a := range v.Args {
if a.Block == b && a.Type.IsMemory() {
storeUse.add(a.ID)

28
src/cmd/compile/internal/ssa/rewriteAMD64.go
View File

@ -35902,18 +35902,18 @@ func rewriteValueAMD64_OpAtomicAdd32_0(v *Value) bool {
_ = typ
// match: (AtomicAdd32 ptr val mem)
// cond:
// result: (AddTupleFirst32 (XADDLlock val ptr mem) val)
// result: (AddTupleFirst32 val (XADDLlock val ptr mem))
for {
ptr := v.Args[0]
val := v.Args[1]
mem := v.Args[2]
v.reset(OpAMD64AddTupleFirst32)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpAMD64XADDLlock, types.NewTuple(typ.UInt32, types.TypeMem))
v0.AddArg(val)
v0.AddArg(ptr)
v0.AddArg(mem)
v.AddArg(v0)
v.AddArg(val)
return true
}
}
@ -35924,18 +35924,18 @@ func rewriteValueAMD64_OpAtomicAdd64_0(v *Value) bool {
_ = typ
// match: (AtomicAdd64 ptr val mem)
// cond:
// result: (AddTupleFirst64 (XADDQlock val ptr mem) val)
// result: (AddTupleFirst64 val (XADDQlock val ptr mem))
for {
ptr := v.Args[0]
val := v.Args[1]
mem := v.Args[2]
v.reset(OpAMD64AddTupleFirst64)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpAMD64XADDQlock, types.NewTuple(typ.UInt64, types.TypeMem))
v0.AddArg(val)
v0.AddArg(ptr)
v0.AddArg(mem)
v.AddArg(v0)
v.AddArg(val)
return true
}
}
@ -40216,7 +40216,7 @@ func rewriteValueAMD64_OpRsh8x8_0(v *Value) bool {
func rewriteValueAMD64_OpSelect0_0(v *Value) bool {
b := v.Block
_ = b
// match: (Select0 <t> (AddTupleFirst32 tuple val))
// match: (Select0 <t> (AddTupleFirst32 val tuple))
// cond:
// result: (ADDL val (Select0 <t> tuple))
for {
@ -40225,8 +40225,8 @@ func rewriteValueAMD64_OpSelect0_0(v *Value) bool {
if v_0.Op != OpAMD64AddTupleFirst32 {
break
}
tuple := v_0.Args[0]
val := v_0.Args[1]
val := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpAMD64ADDL)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpSelect0, t)
@ -40234,7 +40234,7 @@ func rewriteValueAMD64_OpSelect0_0(v *Value) bool {
v.AddArg(v0)
return true
}
// match: (Select0 <t> (AddTupleFirst64 tuple val))
// match: (Select0 <t> (AddTupleFirst64 val tuple))
// cond:
// result: (ADDQ val (Select0 <t> tuple))
for {
@ -40243,8 +40243,8 @@ func rewriteValueAMD64_OpSelect0_0(v *Value) bool {
if v_0.Op != OpAMD64AddTupleFirst64 {
break
}
tuple := v_0.Args[0]
val := v_0.Args[1]
val := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpAMD64ADDQ)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpSelect0, t)
@ -40255,7 +40255,7 @@ func rewriteValueAMD64_OpSelect0_0(v *Value) bool {
return false
}
func rewriteValueAMD64_OpSelect1_0(v *Value) bool {
// match: (Select1 (AddTupleFirst32 tuple _))
// match: (Select1 (AddTupleFirst32 _ tuple))
// cond:
// result: (Select1 tuple)
for {
@ -40263,12 +40263,12 @@ func rewriteValueAMD64_OpSelect1_0(v *Value) bool {
if v_0.Op != OpAMD64AddTupleFirst32 {
break
}
tuple := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpSelect1)
v.AddArg(tuple)
return true
}
// match: (Select1 (AddTupleFirst64 tuple _))
// match: (Select1 (AddTupleFirst64 _ tuple))
// cond:
// result: (Select1 tuple)
for {
@ -40276,7 +40276,7 @@ func rewriteValueAMD64_OpSelect1_0(v *Value) bool {
if v_0.Op != OpAMD64AddTupleFirst64 {
break
}
tuple := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpSelect1)
v.AddArg(tuple)
return true

28
src/cmd/compile/internal/ssa/rewriteS390X.go
View File

@ -898,18 +898,18 @@ func rewriteValueS390X_OpAtomicAdd32_0(v *Value) bool {
_ = typ
// match: (AtomicAdd32 ptr val mem)
// cond:
// result: (AddTupleFirst32 (LAA ptr val mem) val)
// result: (AddTupleFirst32 val (LAA ptr val mem))
for {
ptr := v.Args[0]
val := v.Args[1]
mem := v.Args[2]
v.reset(OpS390XAddTupleFirst32)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpS390XLAA, types.NewTuple(typ.UInt32, types.TypeMem))
v0.AddArg(ptr)
v0.AddArg(val)
v0.AddArg(mem)
v.AddArg(v0)
v.AddArg(val)
return true
}
}
@ -920,18 +920,18 @@ func rewriteValueS390X_OpAtomicAdd64_0(v *Value) bool {
_ = typ
// match: (AtomicAdd64 ptr val mem)
// cond:
// result: (AddTupleFirst64 (LAAG ptr val mem) val)
// result: (AddTupleFirst64 val (LAAG ptr val mem))
for {
ptr := v.Args[0]
val := v.Args[1]
mem := v.Args[2]
v.reset(OpS390XAddTupleFirst64)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpS390XLAAG, types.NewTuple(typ.UInt64, types.TypeMem))
v0.AddArg(ptr)
v0.AddArg(val)
v0.AddArg(mem)
v.AddArg(v0)
v.AddArg(val)
return true
}
}
@ -34159,7 +34159,7 @@ func rewriteValueS390X_OpS390XXORconst_0(v *Value) bool {
func rewriteValueS390X_OpSelect0_0(v *Value) bool {
b := v.Block
_ = b
// match: (Select0 <t> (AddTupleFirst32 tuple val))
// match: (Select0 <t> (AddTupleFirst32 val tuple))
// cond:
// result: (ADDW val (Select0 <t> tuple))
for {
@ -34168,8 +34168,8 @@ func rewriteValueS390X_OpSelect0_0(v *Value) bool {
if v_0.Op != OpS390XAddTupleFirst32 {
break
}
tuple := v_0.Args[0]
val := v_0.Args[1]
val := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpS390XADDW)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpSelect0, t)
@ -34177,7 +34177,7 @@ func rewriteValueS390X_OpSelect0_0(v *Value) bool {
v.AddArg(v0)
return true
}
// match: (Select0 <t> (AddTupleFirst64 tuple val))
// match: (Select0 <t> (AddTupleFirst64 val tuple))
// cond:
// result: (ADD val (Select0 <t> tuple))
for {
@ -34186,8 +34186,8 @@ func rewriteValueS390X_OpSelect0_0(v *Value) bool {
if v_0.Op != OpS390XAddTupleFirst64 {
break
}
tuple := v_0.Args[0]
val := v_0.Args[1]
val := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpS390XADD)
v.AddArg(val)
v0 := b.NewValue0(v.Pos, OpSelect0, t)
@ -34198,7 +34198,7 @@ func rewriteValueS390X_OpSelect0_0(v *Value) bool {
return false
}
func rewriteValueS390X_OpSelect1_0(v *Value) bool {
// match: (Select1 (AddTupleFirst32 tuple _))
// match: (Select1 (AddTupleFirst32 _ tuple))
// cond:
// result: (Select1 tuple)
for {
@ -34206,12 +34206,12 @@ func rewriteValueS390X_OpSelect1_0(v *Value) bool {
if v_0.Op != OpS390XAddTupleFirst32 {
break
}
tuple := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpSelect1)
v.AddArg(tuple)
return true
}
// match: (Select1 (AddTupleFirst64 tuple _))
// match: (Select1 (AddTupleFirst64 _ tuple))
// cond:
// result: (Select1 tuple)
for {
@ -34219,7 +34219,7 @@ func rewriteValueS390X_OpSelect1_0(v *Value) bool {
if v_0.Op != OpS390XAddTupleFirst64 {
break
}
tuple := v_0.Args[0]
tuple := v_0.Args[1]
v.reset(OpSelect1)
v.AddArg(tuple)
return true

22
src/cmd/compile/internal/ssa/schedule.go
View File

@ -132,19 +132,14 @@ func schedule(f *Func) {
}
}
// TODO: make this logic permanent in types.IsMemory?
isMem := func(v *Value) bool {
return v.Type.IsMemory() || v.Type.IsTuple() && v.Type.FieldType(1).IsMemory()
}
for _, b := range f.Blocks {
// Find store chain for block.
// Store chains for different blocks overwrite each other, so
// the calculated store chain is good only for this block.
for _, v := range b.Values {
if v.Op != OpPhi && isMem(v) {
if v.Op != OpPhi && v.Type.IsMemory() {
for _, w := range v.Args {
if isMem(w) {
if w.Type.IsMemory() {
nextMem[w.ID] = v
}
}
@ -164,7 +159,7 @@ func schedule(f *Func) {
uses[w.ID]++
}
// Any load must come before the following store.
if !isMem(v) && isMem(w) {
if !v.Type.IsMemory() && w.Type.IsMemory() {
// v is a load.
s := nextMem[w.ID]
if s == nil || s.Block != b {
@ -315,11 +310,7 @@ func storeOrder(values []*Value, sset *sparseSet, storeNumber []int32) []*Value
if v.Op == OpInitMem || v.Op == OpPhi {
continue
}
a := v
if v.Op == OpSelect1 {
a = a.Args[0]
}
sset.add(a.MemoryArg().ID) // record that v's memory arg is used
sset.add(v.MemoryArg().ID) // record that v's memory arg is used
}
if v.Op == OpNilCheck {
hasNilCheck = true
@ -335,7 +326,7 @@ func storeOrder(values []*Value, sset *sparseSet, storeNumber []int32) []*Value
for _, v := range stores {
if !sset.contains(v.ID) {
if last != nil {
f.Fatalf("two stores live simutaneously: %v and %v", v, last)
f.Fatalf("two stores live simultaneously: %v and %v", v, last)
}
last = v
}
@ -362,9 +353,6 @@ func storeOrder(values []*Value, sset *sparseSet, storeNumber []int32) []*Value
}
break
}
if w.Op == OpSelect1 {
w = w.Args[0]
}
w = w.MemoryArg()
}
var stack []*Value

20
src/cmd/compile/internal/ssa/trim.go
View File

@ -46,10 +46,24 @@ func trim(f *Func) {
v.resetArgs()
continue
}
// Pad the arguments of the remaining phi-ops, so
// Pad the arguments of the remaining phi-ops so
// they match the new predecessor count of `s`.
for len(v.Args) < len(s.Preds) {
v.AddArg(v.Args[0])
// Since s did not have a Phi op corresponding to
// the phi op in b, the other edges coming into s
// must be loopback edges from s, so v is the right
// argument to v!
args := make([]*Value, len(v.Args))
copy(args, v.Args)
v.resetArgs()
for x := 0; x < j; x++ {
v.AddArg(v)
}
v.AddArg(args[0])
for x := j + 1; x < ns; x++ {
v.AddArg(v)
}
for _, a := range args[1:] {
v.AddArg(a)
}
}
b.Values[k] = v

9
src/cmd/compile/internal/ssa/value.go
View File

@ -319,10 +319,8 @@ func (v *Value) RegName() string {
}
// MemoryArg returns the memory argument for the Value.
// The returned value, if non-nil, will be memory-typed,
// except in the case where v is Select1, in which case
// the returned value will be a tuple containing a memory
// type. Otherwise, nil is returned.
// The returned value, if non-nil, will be memory-typed (or a tuple with a memory-typed second part).
// Otherwise, nil is returned.
func (v *Value) MemoryArg() *Value {
if v.Op == OpPhi {
v.Fatalf("MemoryArg on Phi")
@ -331,8 +329,7 @@ func (v *Value) MemoryArg() *Value {
if na == 0 {
return nil
}
if m := v.Args[na-1]; m.Type.IsMemory() ||
(v.Op == OpSelect1 && m.Type.FieldType(1).IsMemory()) {
if m := v.Args[na-1]; m.Type.IsMemory() {
return m
}
return nil

10
src/cmd/compile/internal/types/type.go
View File

@ -1324,10 +1324,12 @@ func (t *Type) ChanDir() ChanDir {
return t.Extra.(*Chan).Dir
}
func (t *Type) IsMemory() bool { return t == TypeMem }
func (t *Type) IsFlags() bool { return t == TypeFlags }
func (t *Type) IsVoid() bool { return t == TypeVoid }
func (t *Type) IsTuple() bool { return t.Etype == TTUPLE }
func (t *Type) IsMemory() bool {
return t == TypeMem || t.Etype == TTUPLE && t.Extra.(*Tuple).second == TypeMem
}
func (t *Type) IsFlags() bool { return t == TypeFlags }
func (t *Type) IsVoid() bool { return t == TypeVoid }
func (t *Type) IsTuple() bool { return t.Etype == TTUPLE }
// IsUntyped reports whether t is an untyped type.
func (t *Type) IsUntyped() bool {