github.com/shogo82148/std@v1.22.1-0.20240327122250-4e474527810c/internal/abi/switch.go (about)

     1  // Copyright 2023 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package abi
     6  
     7  type InterfaceSwitch struct {
     8  	Cache  *InterfaceSwitchCache
     9  	NCases int
    10  
    11  	// Array of NCases elements.
    12  	// Each case must be a non-empty interface type.
    13  	Cases [1]*InterfaceType
    14  }
    15  
    16  type InterfaceSwitchCache struct {
    17  	Mask    uintptr
    18  	Entries [1]InterfaceSwitchCacheEntry
    19  }
    20  
    21  type InterfaceSwitchCacheEntry struct {
    22  	// type of source value (a *Type)
    23  	Typ uintptr
    24  	// case # to dispatch to
    25  	Case int
    26  	// itab to use for resulting case variable (a *runtime.itab)
    27  	Itab uintptr
    28  }
    29  
    30  func UseInterfaceSwitchCache(goarch string) bool
    31  
    32  type TypeAssert struct {
    33  	Cache   *TypeAssertCache
    34  	Inter   *InterfaceType
    35  	CanFail bool
    36  }
    37  type TypeAssertCache struct {
    38  	Mask    uintptr
    39  	Entries [1]TypeAssertCacheEntry
    40  }
    41  type TypeAssertCacheEntry struct {
    42  	// type of source value (a *runtime._type)
    43  	Typ uintptr
    44  	// itab to use for result (a *runtime.itab)
    45  	// nil if CanFail is set and conversion would fail.
    46  	Itab uintptr
    47  }