增加websocket支持

vendor/github.com/bytedance/sonic/loader/pcdata.go

@@ -16,10 +16,6 @@
 
 package loader
 
-import (
-    `encoding/binary`
-)
-
 const (
     _N_PCDATA   = 4
 
@@ -53,16 +49,40 @@ const (
 
 var emptyByte byte
 
-// Pcvalue is the program count corresponding to the value Val
-//   WARN: we use relative value here (to function entry)
-type Pcvalue struct {
-    PC  uint32 // program count relative to function entry
-    Val int32  // value relative to the value in function entry
+func encodeValue(v int) []byte {
+    return encodeVariant(toZigzag(v))
+}
+
+func toZigzag(v int) int {
+    return (v << 1) ^ (v >> 31)
+}
+
+func encodeVariant(v int) []byte {
+    var u int
+    var r []byte
+
+    /* split every 7 bits */
+    for v > 127 {
+        u = v & 0x7f
+        v = v >> 7
+        r = append(r, byte(u) | 0x80)
+    }
+
+    /* check for last one */
+    if v == 0 {
+        return r
+    }
+
+    /* add the last one */
+    r = append(r, byte(v))
+    return r
+}
+
+type Pcvalue struct {
+    PC  uint32 // PC offset from func entry
+    Val int32
 }
 
-// Pcdata represents pc->value mapping table.
-//   WARN: we use ** [Pcdata[i].PC, Pcdata[i+1].PC) **
-//   as the range where the Pcdata[i].Val is effective.
 type Pcdata []Pcvalue
 
 // see https://docs.google.com/document/d/1lyPIbmsYbXnpNj57a261hgOYVpNRcgydurVQIyZOz_o/pub
@@ -70,24 +90,11 @@ func (self Pcdata) MarshalBinary() (data []byte, err error) {
     // delta value always starts from -1
     sv := int32(_PCDATA_START_VAL)
     sp := uint32(0)
-    buf := make([]byte, binary.MaxVarintLen32)
     for _, v := range self {
-        if v.PC < sp {
-            panic("PC must be in ascending order!")
-        }
-        dp := uint64(v.PC - sp)
-        dv := int64(v.Val - sv)
-        if dv == 0 || dp == 0 {
-            continue
-        }
-        n := binary.PutVarint(buf, dv)
-        data = append(data, buf[:n]...)
-        n2 := binary.PutUvarint(buf, dp)
-        data = append(data, buf[:n2]...)
+        data = append(data, encodeVariant(toZigzag(int(v.Val - sv)))...)
+        data = append(data, encodeVariant(int(v.PC - sp))...)
         sp = v.PC
         sv = v.Val
     }
-    // put 0 to indicate ends
-    data = append(data, 0)
     return
-}
+}