prog: refactor bitfields representation

All callers of BitfieldMiddle just want static size (0 for middle).
Make it so: Size for middle bitfields just returns 0. Removes lots of if's.
Introduce Type.UnitSize, which now holds the underlying type for bitfields.
This will be needed to fix #1542 b/c even if UnitSize=4 for last bitfield
Size can be anywhere from 0 to 4 (not necessary equal to UnitSize due to overlapping).

4 files changed, 187 insertions, 187 deletions

diff --git a/sys/test/gen/32_fork_shmem.go b/sys/test/gen/32_fork_shmem.go
index e69f422ea..40d41b49a 100644
--- a/sys/test/gen/32_fork_shmem.go
+++ b/sys/test/gen/32_fork_shmem.go
@@ -89,15 +89,15 @@ var structDescs_32_fork_shmem = []*KeyedStruct{
 		&StructType{Key: StructKey{Name: "syz_bf_struct9"}, FldName: "f1"},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct0", TypeSize: 32}, Fields: []Type{
-		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10}, Vals: []uint64{0, 1, 2}, BitMask: true},
+		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10, BitfieldUnit: 2}, Vals: []uint64{0, 1, 2}, BitMask: true},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 6}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}}},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2", TypeSize: 2}, BitfieldLen: 5, BitfieldMdl: true}, Val: 66},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2"}, BitfieldLen: 5, BitfieldUnit: 2}, Val: 66},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15}, Val: 66},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11}, Path: []string{"parent"}},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11}, Path: []string{"parent"}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15, BitfieldUnit: 4}, Val: 66},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f7", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
@@ -107,15 +107,15 @@ var structDescs_32_fork_shmem = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct10"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct10", TypeSize: 24}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6", TypeSize: 8}, BitfieldOff: 36, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5"}, BitfieldOff: 24, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6"}, BitfieldOff: 36, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12, BitfieldUnit: 8}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f8", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 	}}},
@@ -124,75 +124,75 @@ var structDescs_32_fork_shmem = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct12"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct12", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f6", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct1_internal"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct1_internal", TypeSize: 4}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 10, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 10, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct2"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct2", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0", TypeSize: 8}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct3"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct3", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0", TypeSize: 8}, ArgFormat: 1, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0"}, ArgFormat: 1, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1"}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2"}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3"}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct4"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct4", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct5"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct5", TypeSize: 8}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct6"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct6", TypeSize: 6}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct7"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct7", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct8"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct8", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct9"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct9", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1"}, BitfieldLen: 4, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 }
 
@@ -243,4 +243,4 @@ var consts_32_fork_shmem = []ConstValue{
 	{Name: "ONLY_32BITS_CONST", Value: 1},
 }
 
-const revision_32_fork_shmem = "f5548bb85206b3f719f89273476c099d57505031"
+const revision_32_fork_shmem = "ca3dd713981f8226a2f69b950611e27a721f5f79"
diff --git a/sys/test/gen/32_shmem.go b/sys/test/gen/32_shmem.go
index bea5b7499..25e31c0d0 100644
--- a/sys/test/gen/32_shmem.go
+++ b/sys/test/gen/32_shmem.go
@@ -89,15 +89,15 @@ var structDescs_32_shmem = []*KeyedStruct{
 		&StructType{Key: StructKey{Name: "syz_bf_struct9"}, FldName: "f1"},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct0", TypeSize: 32}, Fields: []Type{
-		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10}, Vals: []uint64{0, 1, 2}, BitMask: true},
+		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10, BitfieldUnit: 2}, Vals: []uint64{0, 1, 2}, BitMask: true},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 6}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}}},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2", TypeSize: 2}, BitfieldLen: 5, BitfieldMdl: true}, Val: 66},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2"}, BitfieldLen: 5, BitfieldUnit: 2}, Val: 66},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15}, Val: 66},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11}, Path: []string{"parent"}},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11}, Path: []string{"parent"}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15, BitfieldUnit: 4}, Val: 66},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f7", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
@@ -107,15 +107,15 @@ var structDescs_32_shmem = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct10"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct10", TypeSize: 24}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6", TypeSize: 8}, BitfieldOff: 36, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5"}, BitfieldOff: 24, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6"}, BitfieldOff: 36, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12, BitfieldUnit: 8}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f8", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 	}}},
@@ -124,75 +124,75 @@ var structDescs_32_shmem = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct12"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct12", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f6", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct1_internal"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct1_internal", TypeSize: 4}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 10, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 10, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct2"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct2", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0", TypeSize: 8}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct3"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct3", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0", TypeSize: 8}, ArgFormat: 1, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0"}, ArgFormat: 1, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1"}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2"}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3"}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct4"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct4", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct5"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct5", TypeSize: 8}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct6"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct6", TypeSize: 6}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct7"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct7", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct8"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct8", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct9"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct9", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1"}, BitfieldLen: 4, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 }
 
@@ -243,4 +243,4 @@ var consts_32_shmem = []ConstValue{
 	{Name: "ONLY_32BITS_CONST", Value: 1},
 }
 
-const revision_32_shmem = "ec2b308d2fcef444f9929135617600cea1ae8c42"
+const revision_32_shmem = "132a815187700652ba8b27e1b4a81de38ccc3d44"
diff --git a/sys/test/gen/64.go b/sys/test/gen/64.go
index fb080b559..6a666322f 100644
--- a/sys/test/gen/64.go
+++ b/sys/test/gen/64.go
@@ -50,13 +50,13 @@ var structDescs_64 = []*KeyedStruct{
 		&BufferType{TypeCommon: TypeCommon{TypeName: "array", FldName: "f5", IsVarlen: true}},
 	}, AlignAttr: 2}},
 	{Key: StructKey{Name: "anybitfields"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "anybitfields", TypeSize: 4}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}, BitfieldLen: 2, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}, BitfieldOff: 2, BitfieldLen: 3, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f3", TypeSize: 1}, BitfieldOff: 5, BitfieldLen: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1"}, BitfieldLen: 2, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2"}, BitfieldOff: 2, BitfieldLen: 3, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f3", TypeSize: 1}, BitfieldOff: 5, BitfieldLen: 1, BitfieldUnit: 1}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f4", TypeSize: 2}, BitfieldLen: 1, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f5", TypeSize: 2}, BitfieldOff: 1, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f6", TypeSize: 2}, BitfieldOff: 11, BitfieldLen: 3}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f4"}, BitfieldLen: 1, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f5"}, BitfieldOff: 1, BitfieldLen: 10, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f6", TypeSize: 2}, BitfieldOff: 11, BitfieldLen: 3, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "anyunion0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "anyunion0", TypeSize: 8}, Fields: []Type{
 		&ResourceType{TypeCommon: TypeCommon{TypeName: "anyres32", FldName: "res32", TypeSize: 4}},
@@ -169,8 +169,8 @@ var structDescs_64 = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f3", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldLen: 5, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f6", TypeSize: 4}, BitfieldOff: 5, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5"}, BitfieldLen: 5, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f6", TypeSize: 4}, BitfieldOff: 5, BitfieldLen: 10, BitfieldUnit: 4}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "offsetof", FldName: "o0", TypeSize: 4}}, BitSize: 8, Offset: true, Path: []string{"f0"}},
@@ -268,12 +268,12 @@ var structDescs_64 = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_align8"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_align8", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}, BitfieldLen: 1, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}, BitfieldOff: 1, BitfieldLen: 1, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}, BitfieldOff: 2, BitfieldLen: 1}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldLen: 1, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f4", TypeSize: 2}, BitfieldOff: 1, BitfieldLen: 1, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f5", TypeSize: 2}, BitfieldOff: 2, BitfieldLen: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0"}, BitfieldLen: 1, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1"}, BitfieldOff: 1, BitfieldLen: 1, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}, BitfieldOff: 2, BitfieldLen: 1, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3"}, BitfieldLen: 1, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f4"}, BitfieldOff: 1, BitfieldLen: 1, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f5", TypeSize: 2}, BitfieldOff: 2, BitfieldLen: 1, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 5}}, IsPad: true},
 	}, AlignAttr: 8}},
 	{Key: StructKey{Name: "syz_array_blob"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_array_blob", TypeSize: 20}, Fields: []Type{
@@ -340,15 +340,15 @@ var structDescs_64 = []*KeyedStruct{
 		&StructType{Key: StructKey{Name: "syz_bf_struct9"}, FldName: "f1"},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct0", TypeSize: 32}, Fields: []Type{
-		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10}, Vals: []uint64{0, 1, 2}, BitMask: true},
+		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10, BitfieldUnit: 2}, Vals: []uint64{0, 1, 2}, BitMask: true},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 6}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}}},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2", TypeSize: 2}, BitfieldLen: 5, BitfieldMdl: true}, Val: 66},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2"}, BitfieldLen: 5, BitfieldUnit: 2}, Val: 66},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15}, Val: 66},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11}, Path: []string{"parent"}},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11}, Path: []string{"parent"}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15, BitfieldUnit: 4}, Val: 66},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f7", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
@@ -358,15 +358,15 @@ var structDescs_64 = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct10"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct10", TypeSize: 24}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6", TypeSize: 8}, BitfieldOff: 36, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5"}, BitfieldOff: 24, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6"}, BitfieldOff: 36, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12, BitfieldUnit: 8}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f8", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 	}}},
@@ -375,82 +375,82 @@ var structDescs_64 = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct12"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct12", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f6", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct1_internal"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct1_internal", TypeSize: 4}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 10, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 10, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct2"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct2", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0", TypeSize: 8}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct3"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct3", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0", TypeSize: 8}, ArgFormat: 1, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0"}, ArgFormat: 1, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1"}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2"}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3"}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct4"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct4", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct5"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct5", TypeSize: 8}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct6"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct6", TypeSize: 6}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct7"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct7", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct8"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct8", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct9"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct9", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1"}, BitfieldLen: 4, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "syz_csum_encode"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_csum_encode", IsVarlen: true}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f0", TypeSize: 2}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16be", FldName: "f1", TypeSize: 2}, ArgFormat: 1}},
 		&ArrayType{TypeCommon: TypeCommon{TypeName: "array", FldName: "f2", IsVarlen: true}, Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: 1, RangeEnd: 4},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f3", TypeSize: 1}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f4", TypeSize: 1}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 1}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f4", TypeSize: 1}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 1}},
 		&BufferType{TypeCommon: TypeCommon{TypeName: "array", FldName: "f5", TypeSize: 4}, Kind: 1, RangeBegin: 4, RangeEnd: 4},
 	}}},
 	{Key: StructKey{Name: "syz_csum_icmp_packet"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_csum_icmp_packet", IsVarlen: true}, Fields: []Type{
@@ -524,13 +524,13 @@ var structDescs_64 = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_length_bf_struct_inner"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_length_bf_struct_inner", TypeSize: 20}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 10, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 32}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldLen: 16, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 16, BitfieldLen: 16}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f6", TypeSize: 4}, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 10, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 32, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4"}, BitfieldLen: 16, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 16, BitfieldLen: 16, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f6", TypeSize: 4}, BitfieldLen: 10, BitfieldUnit: 4}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f7", TypeSize: 4}}, Path: []string{"parent"}},
 	}}},
 	{Key: StructKey{Name: "syz_length_bytesize2_struct"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_length_bytesize2_struct", TypeSize: 16}, Fields: []Type{
@@ -1212,4 +1212,4 @@ var consts_64 = []ConstValue{
 	{Name: "SYS_unsupported"},
 }
 
-const revision_64 = "be3b89fc45ab2bd12fd6bfe85a8c2b0aafe37258"
+const revision_64 = "7e33bc29075fd5999f72b6c59ef49dda32b89937"
diff --git a/sys/test/gen/64_fork.go b/sys/test/gen/64_fork.go
index 596f44923..a55b864f3 100644
--- a/sys/test/gen/64_fork.go
+++ b/sys/test/gen/64_fork.go
@@ -89,15 +89,15 @@ var structDescs_64_fork = []*KeyedStruct{
 		&StructType{Key: StructKey{Name: "syz_bf_struct9"}, FldName: "f1"},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct0", TypeSize: 32}, Fields: []Type{
-		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10}, Vals: []uint64{0, 1, 2}, BitMask: true},
+		&FlagsType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "syz_bf_flags", FldName: "f0", TypeSize: 2}, BitfieldLen: 10, BitfieldUnit: 2}, Vals: []uint64{0, 1, 2}, BitMask: true},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 6}}, IsPad: true},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}}},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2", TypeSize: 2}, BitfieldLen: 5, BitfieldMdl: true}, Val: 66},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f2"}, BitfieldLen: 5, BitfieldUnit: 2}, Val: 66},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}, BitfieldOff: 5, BitfieldLen: 6, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
-		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15}, Val: 66},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11}, Path: []string{"parent"}},
-		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11}, Path: []string{"parent"}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "f4", TypeSize: 4}, BitfieldLen: 15, BitfieldUnit: 4}, Val: 66},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f5", TypeSize: 2}, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "f6", TypeSize: 2}, ArgFormat: 1, BitfieldLen: 11, BitfieldUnit: 2}, Path: []string{"parent"}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f7", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
@@ -107,15 +107,15 @@ var structDescs_64_fork = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct10"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct10", TypeSize: 24}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6", TypeSize: 8}, BitfieldOff: 36, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f5"}, BitfieldOff: 24, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f6"}, BitfieldOff: 36, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f7", TypeSize: 8}, BitfieldOff: 48, BitfieldLen: 12, BitfieldUnit: 8}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f8", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 7}}, IsPad: true},
 	}}},
@@ -124,75 +124,75 @@ var structDescs_64_fork = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct12"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct12", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3", TypeSize: 4}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4", TypeSize: 4}, BitfieldOff: 4, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f3"}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f4"}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f5", TypeSize: 4}, BitfieldOff: 8, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f6", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct1_internal"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct1_internal", TypeSize: 4}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0", TypeSize: 4}, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldOff: 10, BitfieldLen: 10, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f0"}, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1"}, BitfieldOff: 10, BitfieldLen: 10, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f2", TypeSize: 4}, BitfieldOff: 20, BitfieldLen: 10, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct2"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct2", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0", TypeSize: 8}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1", TypeSize: 8}, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2", TypeSize: 8}, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3", TypeSize: 8}, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f0"}, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f1"}, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f2"}, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f3"}, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct3"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct3", TypeSize: 8}, Fields: []Type{
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0", TypeSize: 8}, ArgFormat: 1, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f0"}, ArgFormat: 1, BitfieldLen: 4, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f1"}, ArgFormat: 1, BitfieldOff: 4, BitfieldLen: 8, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f2"}, ArgFormat: 1, BitfieldOff: 12, BitfieldLen: 12, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f3"}, ArgFormat: 1, BitfieldOff: 24, BitfieldLen: 20, BitfieldUnit: 8}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64be", FldName: "f4", TypeSize: 8}, ArgFormat: 1, BitfieldOff: 44, BitfieldLen: 16, BitfieldUnit: 8}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct4"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct4", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct5"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct5", TypeSize: 8}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct6"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct6", TypeSize: 6}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct7"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct7", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct8"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct8", TypeSize: 12}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}, BitfieldLen: 4, BitfieldUnit: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldLen: 4, BitfieldUnit: 2}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
 	}}},
 	{Key: StructKey{Name: "syz_bf_struct9"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "syz_bf_struct9", TypeSize: 4}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f0", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1", TypeSize: 2}, BitfieldLen: 4, BitfieldMdl: true}},
-		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f1"}, BitfieldLen: 4, BitfieldUnit: 2}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f2", TypeSize: 2}, BitfieldOff: 4, BitfieldLen: 4, BitfieldUnit: 2}},
 	}}},
 }
 
@@ -242,4 +242,4 @@ var consts_64_fork = []ConstValue{
 	{Name: "IPPROTO_UDP", Value: 17},
 }
 
-const revision_64_fork = "1fb9ab4432bf155cedcd08a880d6328e94d5d2b8"
+const revision_64_fork = "f7a499875897bbabb3bd01434205689198862c5b"