[dev.ssa] cmd/compile: Allow structs to be SSAd

Break small structs up into their components so they
can be registerized.

Change StructSelect to use field indexes instead of
field offsets, as field offsets aren't unique in the
presence of zero-sized fields.

Change-Id: I2f1dc89f7fa58e1cf58aa1a32b238959d53f62e4
Reviewed-on: https://go-review.googlesource.com/18570
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>

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

@@ -1802,7 +1802,11 @@ func (s *state) expr(n *Node) *ssa.Value {
 		return s.newValue2(ssa.OpLoad, n.Type, p, s.mem())
 
 	case ODOT:
-		// TODO: fix when we can SSA struct types.
+		t := n.Left.Type
+		if canSSAType(t) {
+			v := s.expr(n.Left)
+			return s.newValue1I(ssa.OpStructSelect, n.Type, fieldIdx(n), v)
+		}
 		p := s.addr(n, false)
 		return s.newValue2(ssa.OpLoad, n.Type, p, s.mem())
 
@@ -1876,6 +1880,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 		// such types being spilled.
 		// So here we ensure that we are selecting the underlying pointer
 		// when we build an eface.
+		// TODO: get rid of this now that structs can be SSA'd?
 		for !data.Type.IsPtr() {
 			switch {
 			case data.Type.IsArray():
@@ -1887,7 +1892,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 						// eface type could also be struct{p *byte; q [0]int}
 						continue
 					}
-					data = s.newValue1I(ssa.OpStructSelect, f, data.Type.FieldOff(i), data)
+					data = s.newValue1I(ssa.OpStructSelect, f, i, data)
 					break
 				}
 			default:
@@ -2093,7 +2098,42 @@ func (s *state) assign(left *Node, right *ssa.Value, wb bool, line int32) {
 		}
 		right = s.zeroVal(t)
 	}
-	if left.Op == ONAME && canSSA(left) {
+	if canSSA(left) {
+		if left.Op == ODOT {
+			// We're assigning to a field of an ssa-able value.
+			// We need to build a new structure with the new value for the
+			// field we're assigning and the old values for the other fields.
+			// For instance:
+			//   type T struct {a, b, c int}
+			//   var T x
+			//   x.b = 5
+			// For the x.b = 5 assignment we want to generate x = T{x.a, 5, x.c}
+
+			// Grab information about the structure type.
+			t := left.Left.Type
+			nf := t.NumFields()
+			idx := fieldIdx(left)
+
+			// Grab old value of structure.
+			old := s.expr(left.Left)
+
+			// Make new structure.
+			new := s.newValue0(ssa.StructMakeOp(t.NumFields()), t)
+
+			// Add fields as args.
+			for i := int64(0); i < nf; i++ {
+				if i == idx {
+					new.AddArg(right)
+				} else {
+					new.AddArg(s.newValue1I(ssa.OpStructSelect, t.FieldType(i), i, old))
+				}
+			}
+
+			// Recursively assign the new value we've made to the base of the dot op.
+			s.assign(left.Left, new, false, line)
+			// TODO: do we need to update named values here?
+			return
+		}
 		// Update variable assignment.
 		s.vars[left] = right
 		s.addNamedValue(left, right)
@@ -2157,6 +2197,13 @@ func (s *state) zeroVal(t *Type) *ssa.Value {
 		return s.entryNewValue0(ssa.OpConstInterface, t)
 	case t.IsSlice():
 		return s.entryNewValue0(ssa.OpConstSlice, t)
+	case t.IsStruct():
+		n := t.NumFields()
+		v := s.entryNewValue0(ssa.StructMakeOp(t.NumFields()), t)
+		for i := int64(0); i < n; i++ {
+			v.AddArg(s.zeroVal(t.FieldType(i).(*Type)))
+		}
+		return v
 	}
 	s.Unimplementedf("zero for type %v not implemented", t)
 	return nil
@@ -2440,8 +2487,11 @@ func (s *state) addr(n *Node, bounded bool) *ssa.Value {
 }
 
 // canSSA reports whether n is SSA-able.
-// n must be an ONAME.
+// n must be an ONAME (or an ODOT sequence with an ONAME base).
 func canSSA(n *Node) bool {
+	for n.Op == ODOT {
+		n = n.Left
+	}
 	if n.Op != ONAME {
 		return false
 	}
@@ -2485,10 +2535,7 @@ func canSSAType(t *Type) bool {
 		// introduced by the compiler for variadic functions.
 		return false
 	case TSTRUCT:
-		if countfield(t) > 4 {
-			// 4 is an arbitrary constant.  Same reasoning
-			// as above, lots of small fields would waste
-			// register space needed by other values.
+		if countfield(t) > ssa.MaxStruct {
 			return false
 		}
 		for t1 := t.Type; t1 != nil; t1 = t1.Down {
@@ -2496,8 +2543,7 @@ func canSSAType(t *Type) bool {
 				return false
 			}
 		}
-		return false // until it is implemented
-		//return true
+		return true
 	default:
 		return true
 	}
@@ -4558,6 +4604,34 @@ func autoVar(v *ssa.Value) (*Node, int64) {
 	return loc.N.(*Node), loc.Off
 }
 
+// fieldIdx finds the index of the field referred to by the ODOT node n.
+func fieldIdx(n *Node) int64 {
+	t := n.Left.Type
+	f := n.Right
+	if t.Etype != TSTRUCT {
+		panic("ODOT's LHS is not a struct")
+	}
+
+	var i int64
+	for t1 := t.Type; t1 != nil; t1 = t1.Down {
+		if t1.Etype != TFIELD {
+			panic("non-TFIELD in TSTRUCT")
+		}
+		if t1.Sym != f.Sym {
+			i++
+			continue
+		}
+		if t1.Width != n.Xoffset {
+			panic("field offset doesn't match")
+		}
+		return i
+	}
+	panic(fmt.Sprintf("can't find field in expr %s\n", n))
+
+	// TODO: keep the result of this fucntion somewhere in the ODOT Node
+	// so we don't have to recompute it each time we need it.
+}
+
 // ssaExport exports a bunch of compiler services for the ssa backend.
 type ssaExport struct {
 	log           bool

src/cmd/compile/internal/ssa/TODO

@@ -9,6 +9,8 @@ Correctness
 - Debugging info (check & fix as much as we can)
 - Fix write barriers so cgo tests work (misc/cgo/errors/ptr.go)
 - Re-enable TestStackBarrierProfiling (src/runtime/pprof/pprof_test.go)
+- @ directive in rewrites might read overwritten data.  Save @loc
+  in variable before modifying v.
 
 Optimizations (better compiled code)
 ------------------------------------
@@ -28,7 +30,7 @@ Optimizations (better compiled code)
 - Use better write barrier calls
 - If there are a lot of MOVQ $0, ..., then load
   0 into a register and use the register as the source instead.
-- Allow structs (and arrays of length 1?) to be SSAable.
+- Allow arrays of length 1 (or longer, with all constant indexes?) to be SSAable.
 - Figure out how to make PARAMOUT variables ssa-able.
   They need to get spilled automatically at end-of-function somehow.
 - If strings are being passed around without being interpreted (ptr

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

@@ -13,23 +13,9 @@ func decompose(f *Func) {
 			if v.Op != OpPhi {
 				continue
 			}
-			switch {
-			case v.Type.IsComplex():
-				decomposeComplexPhi(v)
-			case v.Type.IsString():
-				decomposeStringPhi(v)
-			case v.Type.IsSlice():
-				decomposeSlicePhi(v)
-			case v.Type.IsInterface():
-				decomposeInterfacePhi(v)
-				//case v.Type.IsStruct():
-				//	decomposeStructPhi(v)
-			case v.Type.Size() > f.Config.IntSize:
-				f.Unimplementedf("undecomposed type %s", v.Type)
-			}
+			decomposePhi(v)
 		}
 	}
-	// TODO: decompose 64-bit ops on 32-bit archs?
 
 	// Split up named values into their components.
 	// NOTE: the component values we are making are dead at this point.
@@ -92,14 +78,39 @@ func decompose(f *Func) {
 				f.NamedValues[typeName] = append(f.NamedValues[typeName], typ)
 				f.NamedValues[dataName] = append(f.NamedValues[dataName], data)
 			}
-			//case t.IsStruct():
-			// TODO
+		case t.IsStruct():
+			n := t.NumFields()
+			for _, v := range f.NamedValues[name] {
+				for i := int64(0); i < n; i++ {
+					fname := LocalSlot{name.N, t.FieldType(i), name.Off + t.FieldOff(i)} // TODO: use actual field name?
+					x := v.Block.NewValue1I(v.Line, OpStructSelect, t.FieldType(i), i, v)
+					f.NamedValues[fname] = append(f.NamedValues[fname], x)
+				}
+			}
 		case t.Size() > f.Config.IntSize:
-			f.Unimplementedf("undecomposed type %s", t)
+			f.Unimplementedf("undecomposed named type %s", t)
 		}
 	}
 }
 
+func decomposePhi(v *Value) {
+	// TODO: decompose 64-bit ops on 32-bit archs?
+	switch {
+	case v.Type.IsComplex():
+		decomposeComplexPhi(v)
+	case v.Type.IsString():
+		decomposeStringPhi(v)
+	case v.Type.IsSlice():
+		decomposeSlicePhi(v)
+	case v.Type.IsInterface():
+		decomposeInterfacePhi(v)
+	case v.Type.IsStruct():
+		decomposeStructPhi(v)
+	case v.Type.Size() > v.Block.Func.Config.IntSize:
+		v.Unimplementedf("undecomposed type %s", v.Type)
+	}
+}
+
 func decomposeStringPhi(v *Value) {
 	fe := v.Block.Func.Config.fe
 	ptrType := fe.TypeBytePtr()
@@ -184,5 +195,47 @@ func decomposeInterfacePhi(v *Value) {
 	v.AddArg(data)
 }
 func decomposeStructPhi(v *Value) {
-	// TODO
+	t := v.Type
+	n := t.NumFields()
+	var fields [MaxStruct]*Value
+	for i := int64(0); i < n; i++ {
+		fields[i] = v.Block.NewValue0(v.Line, OpPhi, t.FieldType(i))
+	}
+	for _, a := range v.Args {
+		for i := int64(0); i < n; i++ {
+			fields[i].AddArg(a.Block.NewValue1I(v.Line, OpStructSelect, t.FieldType(i), i, a))
+		}
+	}
+	v.Op = StructMakeOp(n)
+	v.AuxInt = 0
+	v.Aux = nil
+	v.resetArgs()
+	v.AddArgs(fields[:n]...)
+
+	// Recursively decompose phis for each field.
+	for _, f := range fields[:n] {
+		decomposePhi(f)
+	}
+}
+
+// MaxStruct is the maximum number of fields a struct
+// can have and still be SSAable.
+const MaxStruct = 4
+
+// StructMakeOp returns the opcode to construct a struct with the
+// given number of fields.
+func StructMakeOp(nf int64) Op {
+	switch nf {
+	case 0:
+		return OpStructMake0
+	case 1:
+		return OpStructMake1
+	case 2:
+		return OpStructMake2
+	case 3:
+		return OpStructMake3
+	case 4:
+		return OpStructMake4
+	}
+	panic("too many fields in an SSAable struct")
 }

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

@@ -150,7 +150,70 @@
 (ArrayIndex (Load ptr mem) idx) && b == v.Args[0].Block -> (Load (PtrIndex <v.Type.PtrTo()> ptr idx) mem)
 (PtrIndex <t> ptr idx) && config.PtrSize == 4 -> (AddPtr ptr (Mul32 <config.fe.TypeInt()> idx (Const32 <config.fe.TypeInt()> [t.Elem().Size()])))
 (PtrIndex <t> ptr idx) && config.PtrSize == 8 -> (AddPtr ptr (Mul64 <config.fe.TypeInt()> idx (Const64 <config.fe.TypeInt()> [t.Elem().Size()])))
-(StructSelect [idx] (Load ptr mem)) -> @v.Args[0].Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [idx] ptr) mem)
+
+// struct operations
+(StructSelect (StructMake1 x)) -> x
+(StructSelect [0] (StructMake2 x _)) -> x
+(StructSelect [1] (StructMake2 _ x)) -> x
+(StructSelect [0] (StructMake3 x _ _)) -> x
+(StructSelect [1] (StructMake3 _ x _)) -> x
+(StructSelect [2] (StructMake3 _ _ x)) -> x
+(StructSelect [0] (StructMake4 x _ _ _)) -> x
+(StructSelect [1] (StructMake4 _ x _ _)) -> x
+(StructSelect [2] (StructMake4 _ _ x _)) -> x
+(StructSelect [3] (StructMake4 _ _ _ x)) -> x
+
+(Load <t> _ _) && t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t) ->
+  (StructMake0)
+(Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t) ->
+  (StructMake1
+    (Load <t.FieldType(0)> ptr mem))
+(Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t) ->
+  (StructMake2
+    (Load <t.FieldType(0)> ptr mem)
+    (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem))
+(Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t) ->
+  (StructMake3
+    (Load <t.FieldType(0)> ptr mem)
+    (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)
+    (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem))
+(Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t) ->
+  (StructMake4
+    (Load <t.FieldType(0)> ptr mem)
+    (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)
+    (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem)
+    (Load <t.FieldType(3)> (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] ptr) mem))
+
+(StructSelect [i] (Load <t> ptr mem)) && !config.fe.CanSSA(t) ->
+  @v.Args[0].Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(i)] ptr) mem)
+
+(Store _ (StructMake0) mem) -> mem
+(Store dst (StructMake1 <t> f0) mem) ->
+  (Store [t.FieldType(0).Size()] dst f0 mem)
+(Store dst (StructMake2 <t> f0 f1) mem) ->
+  (Store [t.FieldType(1).Size()]
+    (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)
+    f1
+    (Store [t.FieldType(0).Size()] dst f0 mem))
+(Store dst (StructMake3 <t> f0 f1 f2) mem) ->
+  (Store [t.FieldType(2).Size()]
+    (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst)
+    f2
+    (Store [t.FieldType(1).Size()]
+      (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)
+      f1
+      (Store [t.FieldType(0).Size()] dst f0 mem)))
+(Store dst (StructMake4 <t> f0 f1 f2 f3) mem) ->
+  (Store [t.FieldType(3).Size()]
+    (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] dst)
+    f3
+    (Store [t.FieldType(2).Size()]
+      (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst)
+      f2
+      (Store [t.FieldType(1).Size()]
+        (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)
+        f1
+        (Store [t.FieldType(0).Size()] dst f0 mem))))
 
 // complex ops
 (ComplexReal (ComplexMake real _  )) -> real
@@ -303,3 +366,24 @@
   (ComplexMake
     (Arg <config.fe.TypeFloat32()> {n} [off])
     (Arg <config.fe.TypeFloat32()> {n} [off+4]))
+
+(Arg <t>) && t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t) ->
+  (StructMake0)
+(Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t) ->
+  (StructMake1
+    (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]))
+(Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t) ->
+  (StructMake2
+    (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])
+    (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]))
+(Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t) ->
+  (StructMake3
+    (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])
+    (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])
+    (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)]))
+(Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t) ->
+  (StructMake4
+    (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])
+    (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])
+    (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)])
+    (Arg <t.FieldType(3)> {n} [off+t.FieldOff(3)]))

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

@@ -335,10 +335,9 @@ var genericOps = []opData{
 	{name: "GetClosurePtr"}, // get closure pointer from dedicated register
 
 	// Indexing operations
-	{name: "ArrayIndex"},   // arg0=array, arg1=index.  Returns a[i]
-	{name: "PtrIndex"},     // arg0=ptr, arg1=index. Computes ptr+sizeof(*v.type)*index, where index is extended to ptrwidth type
-	{name: "OffPtr"},       // arg0 + auxint (arg0 and result are pointers)
-	{name: "StructSelect"}, // arg0=struct, auxint=field offset.  Returns field at that offset (size=size of result type)
+	{name: "ArrayIndex"}, // arg0=array, arg1=index.  Returns a[i]
+	{name: "PtrIndex"},   // arg0=ptr, arg1=index. Computes ptr+sizeof(*v.type)*index, where index is extended to ptrwidth type
+	{name: "OffPtr"},     // arg0 + auxint (arg0 and result are pointers)
 
 	// Slices
 	{name: "SliceMake"},                // arg0=ptr, arg1=len, arg2=cap
@@ -361,6 +360,14 @@ var genericOps = []opData{
 	{name: "ITab", typ: "BytePtr"}, // arg0=interface, returns itable field
 	{name: "IData"},                // arg0=interface, returns data field
 
+	// Structs
+	{name: "StructMake0"},  // Returns struct with 0 fields.
+	{name: "StructMake1"},  // arg0=field0.  Returns struct.
+	{name: "StructMake2"},  // arg0,arg1=field0,field1.  Returns struct.
+	{name: "StructMake3"},  // arg0..2=field0..2.  Returns struct.
+	{name: "StructMake4"},  // arg0..3=field0..3.  Returns struct.
+	{name: "StructSelect"}, // arg0=struct, auxint=field index.  Returns the auxint'th field.
+
 	// Spill&restore ops for the register allocator.  These are
 	// semantically identical to OpCopy; they do not take/return
 	// stores like regular memory ops do.  We can get away without memory

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

@@ -533,7 +533,6 @@ const (
 	OpArrayIndex
 	OpPtrIndex
 	OpOffPtr
-	OpStructSelect
 	OpSliceMake
 	OpSlicePtr
 	OpSliceLen
@@ -547,6 +546,12 @@ const (
 	OpIMake
 	OpITab
 	OpIData
+	OpStructMake0
+	OpStructMake1
+	OpStructMake2
+	OpStructMake3
+	OpStructMake4
+	OpStructSelect
 	OpStoreReg
 	OpLoadReg
 	OpFwdRef
@@ -4236,10 +4241,6 @@ var opcodeTable = [...]opInfo{
 		name:    "OffPtr",
 		generic: true,
 	},
-	{
-		name:    "StructSelect",
-		generic: true,
-	},
 	{
 		name:    "SliceMake",
 		generic: true,
@@ -4292,6 +4293,30 @@ var opcodeTable = [...]opInfo{
 		name:    "IData",
 		generic: true,
 	},
+	{
+		name:    "StructMake0",
+		generic: true,
+	},
+	{
+		name:    "StructMake1",
+		generic: true,
+	},
+	{
+		name:    "StructMake2",
+		generic: true,
+	},
+	{
+		name:    "StructMake3",
+		generic: true,
+	},
+	{
+		name:    "StructMake4",
+		generic: true,
+	},
+	{
+		name:    "StructSelect",
+		generic: true,
+	},
 	{
 		name:    "StoreReg",
 		generic: true,

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

@@ -551,6 +551,149 @@ end0988fc6a62c810b2f4976cb6cf44387f:
 	}
 	goto enda348e93e0036873dd7089a2939c22e3e
 enda348e93e0036873dd7089a2939c22e3e:
+	;
+	// match: (Arg <t>)
+	// cond: t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t)
+	// result: (StructMake0)
+	{
+		t := v.Type
+		if !(t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t)) {
+			goto ende233eeefa826638b0e541bcca531d701
+		}
+		v.Op = OpStructMake0
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		return true
+	}
+	goto ende233eeefa826638b0e541bcca531d701
+ende233eeefa826638b0e541bcca531d701:
+	;
+	// match: (Arg <t> {n} [off])
+	// cond: t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t)
+	// result: (StructMake1     (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]))
+	{
+		t := v.Type
+		n := v.Aux
+		off := v.AuxInt
+		if !(t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t)) {
+			goto ende953e77a0617051dd3f7ad4d58c9ab37
+		}
+		v.Op = OpStructMake1
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.Aux = n
+		v0.AuxInt = off + t.FieldOff(0)
+		v.AddArg(v0)
+		return true
+	}
+	goto ende953e77a0617051dd3f7ad4d58c9ab37
+ende953e77a0617051dd3f7ad4d58c9ab37:
+	;
+	// match: (Arg <t> {n} [off])
+	// cond: t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t)
+	// result: (StructMake2     (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])     (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]))
+	{
+		t := v.Type
+		n := v.Aux
+		off := v.AuxInt
+		if !(t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t)) {
+			goto end9a008048978aabad9de0723212e60631
+		}
+		v.Op = OpStructMake2
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.Aux = n
+		v0.AuxInt = off + t.FieldOff(0)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v1.Aux = n
+		v1.AuxInt = off + t.FieldOff(1)
+		v.AddArg(v1)
+		return true
+	}
+	goto end9a008048978aabad9de0723212e60631
+end9a008048978aabad9de0723212e60631:
+	;
+	// match: (Arg <t> {n} [off])
+	// cond: t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t)
+	// result: (StructMake3     (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])     (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])     (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)]))
+	{
+		t := v.Type
+		n := v.Aux
+		off := v.AuxInt
+		if !(t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t)) {
+			goto end0196e61dbeebc6402f3aa1e9a182210b
+		}
+		v.Op = OpStructMake3
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.Aux = n
+		v0.AuxInt = off + t.FieldOff(0)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v1.Aux = n
+		v1.AuxInt = off + t.FieldOff(1)
+		v.AddArg(v1)
+		v2 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v2.Type = t.FieldType(2)
+		v2.Aux = n
+		v2.AuxInt = off + t.FieldOff(2)
+		v.AddArg(v2)
+		return true
+	}
+	goto end0196e61dbeebc6402f3aa1e9a182210b
+end0196e61dbeebc6402f3aa1e9a182210b:
+	;
+	// match: (Arg <t> {n} [off])
+	// cond: t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t)
+	// result: (StructMake4     (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])     (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])     (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)])     (Arg <t.FieldType(3)> {n} [off+t.FieldOff(3)]))
+	{
+		t := v.Type
+		n := v.Aux
+		off := v.AuxInt
+		if !(t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t)) {
+			goto end6bc133c93e50cb14c2e6cc9401850738
+		}
+		v.Op = OpStructMake4
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.Aux = n
+		v0.AuxInt = off + t.FieldOff(0)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v1.Aux = n
+		v1.AuxInt = off + t.FieldOff(1)
+		v.AddArg(v1)
+		v2 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v2.Type = t.FieldType(2)
+		v2.Aux = n
+		v2.AuxInt = off + t.FieldOff(2)
+		v.AddArg(v2)
+		v3 := b.NewValue0(v.Line, OpArg, TypeInvalid)
+		v3.Type = t.FieldType(3)
+		v3.Aux = n
+		v3.AuxInt = off + t.FieldOff(3)
+		v.AddArg(v3)
+		return true
+	}
+	goto end6bc133c93e50cb14c2e6cc9401850738
+end6bc133c93e50cb14c2e6cc9401850738:
 	;
 	return false
 }
@@ -2274,6 +2417,173 @@ end263ecdc279924bff8771dd1ac3f42222:
 func rewriteValuegeneric_OpLoad(v *Value, config *Config) bool {
 	b := v.Block
 	_ = b
+	// match: (Load <t> _ _)
+	// cond: t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t)
+	// result: (StructMake0)
+	{
+		t := v.Type
+		if !(t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t)) {
+			goto end8d25f5c949948132921b6be29ede6bde
+		}
+		v.Op = OpStructMake0
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		return true
+	}
+	goto end8d25f5c949948132921b6be29ede6bde
+end8d25f5c949948132921b6be29ede6bde:
+	;
+	// match: (Load <t> ptr mem)
+	// cond: t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t)
+	// result: (StructMake1     (Load <t.FieldType(0)> ptr mem))
+	{
+		t := v.Type
+		ptr := v.Args[0]
+		mem := v.Args[1]
+		if !(t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t)) {
+			goto endfe908e5a8617dd39df2f9b2b92e93ae5
+		}
+		v.Op = OpStructMake1
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.AddArg(ptr)
+		v0.AddArg(mem)
+		v.AddArg(v0)
+		return true
+	}
+	goto endfe908e5a8617dd39df2f9b2b92e93ae5
+endfe908e5a8617dd39df2f9b2b92e93ae5:
+	;
+	// match: (Load <t> ptr mem)
+	// cond: t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t)
+	// result: (StructMake2     (Load <t.FieldType(0)> ptr mem)     (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem))
+	{
+		t := v.Type
+		ptr := v.Args[0]
+		mem := v.Args[1]
+		if !(t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t)) {
+			goto end20e20e64004b765012cfb80c575ef27b
+		}
+		v.Op = OpStructMake2
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.AddArg(ptr)
+		v0.AddArg(mem)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v2 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v2.Type = t.FieldType(1).PtrTo()
+		v2.AuxInt = t.FieldOff(1)
+		v2.AddArg(ptr)
+		v1.AddArg(v2)
+		v1.AddArg(mem)
+		v.AddArg(v1)
+		return true
+	}
+	goto end20e20e64004b765012cfb80c575ef27b
+end20e20e64004b765012cfb80c575ef27b:
+	;
+	// match: (Load <t> ptr mem)
+	// cond: t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t)
+	// result: (StructMake3     (Load <t.FieldType(0)> ptr mem)     (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)     (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem))
+	{
+		t := v.Type
+		ptr := v.Args[0]
+		mem := v.Args[1]
+		if !(t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t)) {
+			goto ende612bf71067ed67541735cdc8b5a3288
+		}
+		v.Op = OpStructMake3
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.AddArg(ptr)
+		v0.AddArg(mem)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v2 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v2.Type = t.FieldType(1).PtrTo()
+		v2.AuxInt = t.FieldOff(1)
+		v2.AddArg(ptr)
+		v1.AddArg(v2)
+		v1.AddArg(mem)
+		v.AddArg(v1)
+		v3 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v3.Type = t.FieldType(2)
+		v4 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v4.Type = t.FieldType(2).PtrTo()
+		v4.AuxInt = t.FieldOff(2)
+		v4.AddArg(ptr)
+		v3.AddArg(v4)
+		v3.AddArg(mem)
+		v.AddArg(v3)
+		return true
+	}
+	goto ende612bf71067ed67541735cdc8b5a3288
+ende612bf71067ed67541735cdc8b5a3288:
+	;
+	// match: (Load <t> ptr mem)
+	// cond: t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t)
+	// result: (StructMake4     (Load <t.FieldType(0)> ptr mem)     (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)     (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem)     (Load <t.FieldType(3)> (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] ptr) mem))
+	{
+		t := v.Type
+		ptr := v.Args[0]
+		mem := v.Args[1]
+		if !(t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t)) {
+			goto end46c66c64d9030f2cc9a7a767f67953d1
+		}
+		v.Op = OpStructMake4
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v0 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v0.Type = t.FieldType(0)
+		v0.AddArg(ptr)
+		v0.AddArg(mem)
+		v.AddArg(v0)
+		v1 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v1.Type = t.FieldType(1)
+		v2 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v2.Type = t.FieldType(1).PtrTo()
+		v2.AuxInt = t.FieldOff(1)
+		v2.AddArg(ptr)
+		v1.AddArg(v2)
+		v1.AddArg(mem)
+		v.AddArg(v1)
+		v3 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v3.Type = t.FieldType(2)
+		v4 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v4.Type = t.FieldType(2).PtrTo()
+		v4.AuxInt = t.FieldOff(2)
+		v4.AddArg(ptr)
+		v3.AddArg(v4)
+		v3.AddArg(mem)
+		v.AddArg(v3)
+		v5 := b.NewValue0(v.Line, OpLoad, TypeInvalid)
+		v5.Type = t.FieldType(3)
+		v6 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v6.Type = t.FieldType(3).PtrTo()
+		v6.AuxInt = t.FieldOff(3)
+		v6.AddArg(ptr)
+		v5.AddArg(v6)
+		v5.AddArg(mem)
+		v.AddArg(v5)
+		return true
+	}
+	goto end46c66c64d9030f2cc9a7a767f67953d1
+end46c66c64d9030f2cc9a7a767f67953d1:
+	;
 	// match: (Load <t> ptr mem)
 	// cond: t.IsComplex() && t.Size() == 8
 	// result: (ComplexMake     (Load <config.fe.TypeFloat32()> ptr mem)     (Load <config.fe.TypeFloat32()>       (OffPtr <config.fe.TypeFloat32().PtrTo()> [4] ptr)       mem)     )
@@ -3067,6 +3377,187 @@ end526acc0a705137a5d25577499206720b:
 func rewriteValuegeneric_OpStore(v *Value, config *Config) bool {
 	b := v.Block
 	_ = b
+	// match: (Store _ (StructMake0) mem)
+	// cond:
+	// result: mem
+	{
+		if v.Args[1].Op != OpStructMake0 {
+			goto endd4f364b0adfc229d8c200af183d4c808
+		}
+		mem := v.Args[2]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = mem.Type
+		v.AddArg(mem)
+		return true
+	}
+	goto endd4f364b0adfc229d8c200af183d4c808
+endd4f364b0adfc229d8c200af183d4c808:
+	;
+	// match: (Store dst (StructMake1 <t> f0) mem)
+	// cond:
+	// result: (Store [t.FieldType(0).Size()] dst f0 mem)
+	{
+		dst := v.Args[0]
+		if v.Args[1].Op != OpStructMake1 {
+			goto end2cff6d06f4440132f48ca374b6b1e9d8
+		}
+		t := v.Args[1].Type
+		f0 := v.Args[1].Args[0]
+		mem := v.Args[2]
+		v.Op = OpStore
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.AuxInt = t.FieldType(0).Size()
+		v.AddArg(dst)
+		v.AddArg(f0)
+		v.AddArg(mem)
+		return true
+	}
+	goto end2cff6d06f4440132f48ca374b6b1e9d8
+end2cff6d06f4440132f48ca374b6b1e9d8:
+	;
+	// match: (Store dst (StructMake2 <t> f0 f1) mem)
+	// cond:
+	// result: (Store [t.FieldType(1).Size()]     (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)     f1     (Store [t.FieldType(0).Size()] dst f0 mem))
+	{
+		dst := v.Args[0]
+		if v.Args[1].Op != OpStructMake2 {
+			goto end4e8ede6cc575a287795971da6b637973
+		}
+		t := v.Args[1].Type
+		f0 := v.Args[1].Args[0]
+		f1 := v.Args[1].Args[1]
+		mem := v.Args[2]
+		v.Op = OpStore
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.AuxInt = t.FieldType(1).Size()
+		v0 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v0.Type = t.FieldType(1).PtrTo()
+		v0.AuxInt = t.FieldOff(1)
+		v0.AddArg(dst)
+		v.AddArg(v0)
+		v.AddArg(f1)
+		v1 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v1.AuxInt = t.FieldType(0).Size()
+		v1.AddArg(dst)
+		v1.AddArg(f0)
+		v1.AddArg(mem)
+		v1.Type = TypeMem
+		v.AddArg(v1)
+		return true
+	}
+	goto end4e8ede6cc575a287795971da6b637973
+end4e8ede6cc575a287795971da6b637973:
+	;
+	// match: (Store dst (StructMake3 <t> f0 f1 f2) mem)
+	// cond:
+	// result: (Store [t.FieldType(2).Size()]     (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst)     f2     (Store [t.FieldType(1).Size()]       (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)       f1       (Store [t.FieldType(0).Size()] dst f0 mem)))
+	{
+		dst := v.Args[0]
+		if v.Args[1].Op != OpStructMake3 {
+			goto end6ad675267724a87c8f852dd1e185e911
+		}
+		t := v.Args[1].Type
+		f0 := v.Args[1].Args[0]
+		f1 := v.Args[1].Args[1]
+		f2 := v.Args[1].Args[2]
+		mem := v.Args[2]
+		v.Op = OpStore
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.AuxInt = t.FieldType(2).Size()
+		v0 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v0.Type = t.FieldType(2).PtrTo()
+		v0.AuxInt = t.FieldOff(2)
+		v0.AddArg(dst)
+		v.AddArg(v0)
+		v.AddArg(f2)
+		v1 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v1.AuxInt = t.FieldType(1).Size()
+		v2 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v2.Type = t.FieldType(1).PtrTo()
+		v2.AuxInt = t.FieldOff(1)
+		v2.AddArg(dst)
+		v1.AddArg(v2)
+		v1.AddArg(f1)
+		v3 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v3.AuxInt = t.FieldType(0).Size()
+		v3.AddArg(dst)
+		v3.AddArg(f0)
+		v3.AddArg(mem)
+		v3.Type = TypeMem
+		v1.AddArg(v3)
+		v1.Type = TypeMem
+		v.AddArg(v1)
+		return true
+	}
+	goto end6ad675267724a87c8f852dd1e185e911
+end6ad675267724a87c8f852dd1e185e911:
+	;
+	// match: (Store dst (StructMake4 <t> f0 f1 f2 f3) mem)
+	// cond:
+	// result: (Store [t.FieldType(3).Size()]     (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] dst)     f3     (Store [t.FieldType(2).Size()]       (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst)       f2       (Store [t.FieldType(1).Size()]         (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst)         f1         (Store [t.FieldType(0).Size()] dst f0 mem))))
+	{
+		dst := v.Args[0]
+		if v.Args[1].Op != OpStructMake4 {
+			goto end7ea91abd44794f7653374502a5a405ea
+		}
+		t := v.Args[1].Type
+		f0 := v.Args[1].Args[0]
+		f1 := v.Args[1].Args[1]
+		f2 := v.Args[1].Args[2]
+		f3 := v.Args[1].Args[3]
+		mem := v.Args[2]
+		v.Op = OpStore
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.AuxInt = t.FieldType(3).Size()
+		v0 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v0.Type = t.FieldType(3).PtrTo()
+		v0.AuxInt = t.FieldOff(3)
+		v0.AddArg(dst)
+		v.AddArg(v0)
+		v.AddArg(f3)
+		v1 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v1.AuxInt = t.FieldType(2).Size()
+		v2 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v2.Type = t.FieldType(2).PtrTo()
+		v2.AuxInt = t.FieldOff(2)
+		v2.AddArg(dst)
+		v1.AddArg(v2)
+		v1.AddArg(f2)
+		v3 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v3.AuxInt = t.FieldType(1).Size()
+		v4 := b.NewValue0(v.Line, OpOffPtr, TypeInvalid)
+		v4.Type = t.FieldType(1).PtrTo()
+		v4.AuxInt = t.FieldOff(1)
+		v4.AddArg(dst)
+		v3.AddArg(v4)
+		v3.AddArg(f1)
+		v5 := b.NewValue0(v.Line, OpStore, TypeInvalid)
+		v5.AuxInt = t.FieldType(0).Size()
+		v5.AddArg(dst)
+		v5.AddArg(f0)
+		v5.AddArg(mem)
+		v5.Type = TypeMem
+		v3.AddArg(v5)
+		v3.Type = TypeMem
+		v1.AddArg(v3)
+		v1.Type = TypeMem
+		v.AddArg(v1)
+		return true
+	}
+	goto end7ea91abd44794f7653374502a5a405ea
+end7ea91abd44794f7653374502a5a405ea:
+	;
 	// match: (Store [8] dst (ComplexMake real imag) mem)
 	// cond:
 	// result: (Store [4]     (OffPtr <config.fe.TypeFloat32().PtrTo()> [4] dst)     imag     (Store [4] dst real mem))
@@ -3386,16 +3877,237 @@ end061edc5d85c73ad909089af2556d9380:
 func rewriteValuegeneric_OpStructSelect(v *Value, config *Config) bool {
 	b := v.Block
 	_ = b
-	// match: (StructSelect [idx] (Load ptr mem))
+	// match: (StructSelect (StructMake1 x))
+	// cond:
+	// result: x
+	{
+		if v.Args[0].Op != OpStructMake1 {
+			goto end17af582e7eba5216b4a51fe6c9206d3c
+		}
+		x := v.Args[0].Args[0]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end17af582e7eba5216b4a51fe6c9206d3c
+end17af582e7eba5216b4a51fe6c9206d3c:
+	;
+	// match: (StructSelect [0] (StructMake2 x _))
 	// cond:
-	// result: @v.Args[0].Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [idx] ptr) mem)
+	// result: x
 	{
-		idx := v.AuxInt
+		if v.AuxInt != 0 {
+			goto end355cfff99c8e9af975c3ae450d49b7f9
+		}
+		if v.Args[0].Op != OpStructMake2 {
+			goto end355cfff99c8e9af975c3ae450d49b7f9
+		}
+		x := v.Args[0].Args[0]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end355cfff99c8e9af975c3ae450d49b7f9
+end355cfff99c8e9af975c3ae450d49b7f9:
+	;
+	// match: (StructSelect [1] (StructMake2 _ x))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 1 {
+			goto end69baa65e494ef9ae154e0943b53734f9
+		}
+		if v.Args[0].Op != OpStructMake2 {
+			goto end69baa65e494ef9ae154e0943b53734f9
+		}
+		x := v.Args[0].Args[1]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end69baa65e494ef9ae154e0943b53734f9
+end69baa65e494ef9ae154e0943b53734f9:
+	;
+	// match: (StructSelect [0] (StructMake3 x _ _))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 0 {
+			goto endb0d98e2c46bb51c9abd4c3543392e0ec
+		}
+		if v.Args[0].Op != OpStructMake3 {
+			goto endb0d98e2c46bb51c9abd4c3543392e0ec
+		}
+		x := v.Args[0].Args[0]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto endb0d98e2c46bb51c9abd4c3543392e0ec
+endb0d98e2c46bb51c9abd4c3543392e0ec:
+	;
+	// match: (StructSelect [1] (StructMake3 _ x _))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 1 {
+			goto end2e40457286d26c2f14ad4fd127946773
+		}
+		if v.Args[0].Op != OpStructMake3 {
+			goto end2e40457286d26c2f14ad4fd127946773
+		}
+		x := v.Args[0].Args[1]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end2e40457286d26c2f14ad4fd127946773
+end2e40457286d26c2f14ad4fd127946773:
+	;
+	// match: (StructSelect [2] (StructMake3 _ _ x))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 2 {
+			goto end3e3b96ad431206175d002ece87aa1409
+		}
+		if v.Args[0].Op != OpStructMake3 {
+			goto end3e3b96ad431206175d002ece87aa1409
+		}
+		x := v.Args[0].Args[2]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end3e3b96ad431206175d002ece87aa1409
+end3e3b96ad431206175d002ece87aa1409:
+	;
+	// match: (StructSelect [0] (StructMake4 x _ _ _))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 0 {
+			goto end09f8a1ffa3d8c3124bc6d4083b941108
+		}
+		if v.Args[0].Op != OpStructMake4 {
+			goto end09f8a1ffa3d8c3124bc6d4083b941108
+		}
+		x := v.Args[0].Args[0]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end09f8a1ffa3d8c3124bc6d4083b941108
+end09f8a1ffa3d8c3124bc6d4083b941108:
+	;
+	// match: (StructSelect [1] (StructMake4 _ x _ _))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 1 {
+			goto endd3ef25e605a927e9251be6d9221f4acf
+		}
+		if v.Args[0].Op != OpStructMake4 {
+			goto endd3ef25e605a927e9251be6d9221f4acf
+		}
+		x := v.Args[0].Args[1]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto endd3ef25e605a927e9251be6d9221f4acf
+endd3ef25e605a927e9251be6d9221f4acf:
+	;
+	// match: (StructSelect [2] (StructMake4 _ _ x _))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 2 {
+			goto end0438e22cc8f41123fa42009a81ee723a
+		}
+		if v.Args[0].Op != OpStructMake4 {
+			goto end0438e22cc8f41123fa42009a81ee723a
+		}
+		x := v.Args[0].Args[2]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end0438e22cc8f41123fa42009a81ee723a
+end0438e22cc8f41123fa42009a81ee723a:
+	;
+	// match: (StructSelect [3] (StructMake4 _ _ _ x))
+	// cond:
+	// result: x
+	{
+		if v.AuxInt != 3 {
+			goto end56a7c7781fee35eeff0a3652dc206012
+		}
+		if v.Args[0].Op != OpStructMake4 {
+			goto end56a7c7781fee35eeff0a3652dc206012
+		}
+		x := v.Args[0].Args[3]
+		v.Op = OpCopy
+		v.AuxInt = 0
+		v.Aux = nil
+		v.resetArgs()
+		v.Type = x.Type
+		v.AddArg(x)
+		return true
+	}
+	goto end56a7c7781fee35eeff0a3652dc206012
+end56a7c7781fee35eeff0a3652dc206012:
+	;
+	// match: (StructSelect [i] (Load <t> ptr mem))
+	// cond: !config.fe.CanSSA(t)
+	// result: @v.Args[0].Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(i)] ptr) mem)
+	{
+		i := v.AuxInt
 		if v.Args[0].Op != OpLoad {
-			goto end27abc5bf0299ce1bd5457af6ce8e3fba
+			goto end2afd47b4fcaaab7a73325bd8a75e3e8e
 		}
+		t := v.Args[0].Type
 		ptr := v.Args[0].Args[0]
 		mem := v.Args[0].Args[1]
+		if !(!config.fe.CanSSA(t)) {
+			goto end2afd47b4fcaaab7a73325bd8a75e3e8e
+		}
 		v0 := v.Args[0].Block.NewValue0(v.Line, OpLoad, TypeInvalid)
 		v.Op = OpCopy
 		v.AuxInt = 0
@@ -3405,14 +4117,14 @@ func rewriteValuegeneric_OpStructSelect(v *Value, config *Config) bool {
 		v0.Type = v.Type
 		v1 := v.Args[0].Block.NewValue0(v.Line, OpOffPtr, TypeInvalid)
 		v1.Type = v.Type.PtrTo()
-		v1.AuxInt = idx
+		v1.AuxInt = t.FieldOff(i)
 		v1.AddArg(ptr)
 		v0.AddArg(v1)
 		v0.AddArg(mem)
 		return true
 	}
-	goto end27abc5bf0299ce1bd5457af6ce8e3fba
-end27abc5bf0299ce1bd5457af6ce8e3fba:
+	goto end2afd47b4fcaaab7a73325bd8a75e3e8e
+end2afd47b4fcaaab7a73325bd8a75e3e8e:
 	;
 	return false
 }