fastconv.go raw

   1  package rt
   2  
   3  import (
   4  	"unsafe"
   5  	"encoding/json"
   6  )
   7  
   8  // Copied from Golang
   9  var staticuint64s = [...]uint64{
  10  	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  11  	0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
  12  	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
  13  	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
  14  	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
  15  	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
  16  	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
  17  	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
  18  	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
  19  	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
  20  	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
  21  	0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
  22  	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
  23  	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
  24  	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
  25  	0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
  26  	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
  27  	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
  28  	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
  29  	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
  30  	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
  31  	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
  32  	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
  33  	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
  34  	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
  35  	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
  36  	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
  37  	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
  38  	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
  39  	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
  40  	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
  41  	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
  42  }
  43  
  44  const maxZero = 1024 // must match value in reflect/value.go:maxZero cmd/compile/internal/gc/walk.go:zeroValSize
  45  var zeroVal [maxZero]byte
  46  
  47  
  48  type TslicePool struct {
  49  	pool   []GoSlice
  50  	index  int
  51  }
  52  
  53  func NewTslicePool (hint int) TslicePool {
  54  	return TslicePool{
  55  		pool:  make([]GoSlice, hint, hint),
  56  		index: 0,
  57  	}
  58  }
  59  
  60  func (self *TslicePool) Conv(val GoSlice, typ *GoType, ep *interface{}) {
  61  	var vp unsafe.Pointer
  62  
  63  	if ((*GoSlice)(unsafe.Pointer(&val))).Ptr == nil {
  64  		vp = unsafe.Pointer(&zeroVal[0])
  65  	} else if self.index < len(self.pool) {
  66  		dst := &(self.pool)[self.index]
  67  		*dst = val
  68  		self.index++
  69  		vp = unsafe.Pointer(dst)
  70  	} else {
  71  		vp = Mallocgc(unsafe.Sizeof(val), BytesType, true)
  72  	}
  73  	*((*GoEface)(unsafe.Pointer(ep))) = GoEface{Type: typ, Value: vp}
  74  }
  75  
  76  func (self *TslicePool) Free()  {
  77  	self.pool = nil
  78  }
  79  
  80  type TstringPool struct {
  81  	pool  []string
  82  	index int
  83  }
  84  
  85  func NewTstringPool (hint int) TstringPool {
  86  	return TstringPool{
  87  		pool: make([]string, hint),
  88  		index: 0,
  89  	}
  90  }
  91  
  92  func (self *TstringPool) Conv(val string, ep *interface{}) {
  93  	var vp unsafe.Pointer
  94  	if val == "" {
  95  		vp = unsafe.Pointer(&zeroVal[0])
  96  	} else if self.index < len(self.pool) {
  97  		dst := &(self.pool)[self.index]
  98  		*dst = val
  99  		self.index++
 100  		vp = unsafe.Pointer(dst)
 101  	} else {
 102  		vp = Mallocgc(unsafe.Sizeof(val), StringType, true)
 103  	}
 104  
 105  	// convert into interface{}
 106  	*((*GoEface)(unsafe.Pointer(ep))) = GoEface{Type: StringType, Value: vp}
 107  }
 108  
 109  
 110  func (self *TstringPool) ConvNum(val json.Number, ep *interface{}) {
 111  	var vp unsafe.Pointer
 112  	if val == "" {
 113  		vp = unsafe.Pointer(&zeroVal[0])
 114  	} else if self.index < len(self.pool) {
 115  		dst := &(self.pool)[self.index]
 116  		*dst = string(val)
 117  		self.index++
 118  		vp = unsafe.Pointer(dst)
 119  	} else {
 120  		vp = Mallocgc(unsafe.Sizeof(val), StringType, true)
 121  	}
 122  
 123  	// convert into interface{}
 124  	*((*GoEface)(unsafe.Pointer(ep))) = GoEface{Type: JsonNumberType, Value: vp}
 125  }
 126  
 127  
 128  func (self *TstringPool) Free()  {
 129  	self.pool = nil
 130  }
 131  
 132  type T64Pool struct {
 133  	pool  []uint64
 134  	index int
 135  }
 136  
 137  func NewT64Pool (hint int) T64Pool {
 138  	return T64Pool{
 139  		pool: make([]uint64, hint, hint),
 140  		index: 0,
 141  	}
 142  }
 143  
 144  func (self *T64Pool) Conv(val uint64, typ *GoType, ep *interface{}) {
 145  	var vp unsafe.Pointer
 146  	if val < uint64(len(staticuint64s)) {
 147  		vp = unsafe.Pointer(&staticuint64s[val])
 148  	} else if self.index < len(self.pool) {
 149  		dst := &(self.pool)[self.index]
 150  		*dst = val
 151  		self.index++
 152  		vp = unsafe.Pointer(dst)
 153  	} else {
 154  		vp = Mallocgc(8, Uint64Type, false)
 155  	}
 156  
 157  	// convert into interface{}
 158  	*((*GoEface)(unsafe.Pointer(ep))) = GoEface{Type: typ, Value: vp}
 159  }
 160  
 161  func (self *T64Pool) Free()  {
 162  	self.pool = nil
 163  }
 164  
 165  func ConvTBool(val bool, ep *interface{}) {
 166  	var vp unsafe.Pointer
 167  	if val {
 168  		vp = unsafe.Pointer(&staticuint64s[1])
 169  	} else {
 170  		vp = unsafe.Pointer(&staticuint64s[0])
 171  	}
 172  
 173  	*((*GoEface)(unsafe.Pointer(ep))) = GoEface{Type: BoolType, Value: vp}
 174  }
 175  
 176