mirror of
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synced 2025-05-05 15:43:04 +00:00
runtime: eliminate runtime.hselect
Now the registration phase looks like:
var cases [4]runtime.scases
var order [8]uint16
selectsend(&cases[0], c1, &v1)
selectrecv(&cases[1], c2, &v2, nil)
selectrecv(&cases[2], c3, &v3, &ok)
selectdefault(&cases[3])
chosen := selectgo(&cases[0], &order[0], 4)
Primarily, this is just preparation for having the compiler open-code
selectsend, selectrecv, and selectdefault.
As a minor benefit, order can now be layed out separately on the stack
in the pointer-free segment, so it won't take up space in the
function's stack pointer maps.
Change-Id: I5552ba594201efd31fcb40084da20b42ea569a45
Reviewed-on: https://go-review.googlesource.com/37933
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This commit is contained in:
Matthew Dempsky
parent
a4aa2e0c28
commit
3aa53b3135
@ -111,49 +111,48 @@ var runtimeDecls = [...]struct {
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{"selectnbsend", funcTag, 87},
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{"selectnbrecv", funcTag, 88},
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{"selectnbrecv2", funcTag, 90},
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{"newselect", funcTag, 91},
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{"selectsend", funcTag, 92},
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{"selectrecv", funcTag, 93},
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{"selectsend", funcTag, 91},
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{"selectrecv", funcTag, 92},
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{"selectdefault", funcTag, 55},
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{"selectgo", funcTag, 94},
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{"selectgo", funcTag, 93},
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{"block", funcTag, 5},
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{"makeslice", funcTag, 96},
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{"makeslice64", funcTag, 97},
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{"growslice", funcTag, 98},
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{"memmove", funcTag, 99},
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{"memclrNoHeapPointers", funcTag, 100},
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{"memclrHasPointers", funcTag, 100},
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{"memequal", funcTag, 101},
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{"memequal8", funcTag, 102},
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{"memequal16", funcTag, 102},
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{"memequal32", funcTag, 102},
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{"memequal64", funcTag, 102},
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{"memequal128", funcTag, 102},
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{"int64div", funcTag, 103},
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{"uint64div", funcTag, 104},
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{"int64mod", funcTag, 103},
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{"uint64mod", funcTag, 104},
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{"float64toint64", funcTag, 105},
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{"float64touint64", funcTag, 106},
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{"float64touint32", funcTag, 107},
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{"int64tofloat64", funcTag, 108},
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{"uint64tofloat64", funcTag, 109},
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{"uint32tofloat64", funcTag, 110},
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{"complex128div", funcTag, 111},
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{"racefuncenter", funcTag, 112},
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{"makeslice", funcTag, 95},
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{"makeslice64", funcTag, 96},
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{"growslice", funcTag, 97},
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{"memmove", funcTag, 98},
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{"memclrNoHeapPointers", funcTag, 99},
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{"memclrHasPointers", funcTag, 99},
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{"memequal", funcTag, 100},
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{"memequal8", funcTag, 101},
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{"memequal16", funcTag, 101},
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{"memequal32", funcTag, 101},
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{"memequal64", funcTag, 101},
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{"memequal128", funcTag, 101},
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{"int64div", funcTag, 102},
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{"uint64div", funcTag, 103},
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{"int64mod", funcTag, 102},
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{"uint64mod", funcTag, 103},
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{"float64toint64", funcTag, 104},
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{"float64touint64", funcTag, 105},
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{"float64touint32", funcTag, 106},
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{"int64tofloat64", funcTag, 107},
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{"uint64tofloat64", funcTag, 108},
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{"uint32tofloat64", funcTag, 109},
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{"complex128div", funcTag, 110},
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{"racefuncenter", funcTag, 111},
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{"racefuncexit", funcTag, 5},
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{"raceread", funcTag, 112},
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{"racewrite", funcTag, 112},
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{"racereadrange", funcTag, 113},
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{"racewriterange", funcTag, 113},
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{"msanread", funcTag, 113},
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{"msanwrite", funcTag, 113},
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{"raceread", funcTag, 111},
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{"racewrite", funcTag, 111},
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{"racereadrange", funcTag, 112},
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{"racewriterange", funcTag, 112},
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{"msanread", funcTag, 112},
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{"msanwrite", funcTag, 112},
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{"support_popcnt", varTag, 11},
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{"support_sse41", varTag, 11},
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}
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func runtimeTypes() []*types.Type {
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var typs [114]*types.Type
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var typs [113]*types.Type
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typs[0] = types.Bytetype
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typs[1] = types.NewPtr(typs[0])
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typs[2] = types.Types[TANY]
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@ -245,28 +244,27 @@ func runtimeTypes() []*types.Type {
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typs[88] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[77])}, []*Node{anonfield(typs[11])})
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typs[89] = types.NewPtr(typs[11])
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typs[90] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[89]), anonfield(typs[77])}, []*Node{anonfield(typs[11])})
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typs[91] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[15]), anonfield(typs[8])}, nil)
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typs[92] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[80]), anonfield(typs[3])}, nil)
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typs[93] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[77]), anonfield(typs[3]), anonfield(typs[89])}, nil)
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typs[94] = functype(nil, []*Node{anonfield(typs[1])}, []*Node{anonfield(typs[32])})
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typs[95] = types.NewSlice(typs[2])
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typs[96] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[32]), anonfield(typs[32])}, []*Node{anonfield(typs[95])})
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typs[97] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[15]), anonfield(typs[15])}, []*Node{anonfield(typs[95])})
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typs[98] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[95]), anonfield(typs[32])}, []*Node{anonfield(typs[95])})
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typs[99] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3]), anonfield(typs[48])}, nil)
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typs[100] = functype(nil, []*Node{anonfield(typs[57]), anonfield(typs[48])}, nil)
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typs[101] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3]), anonfield(typs[48])}, []*Node{anonfield(typs[11])})
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typs[102] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3])}, []*Node{anonfield(typs[11])})
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typs[103] = functype(nil, []*Node{anonfield(typs[15]), anonfield(typs[15])}, []*Node{anonfield(typs[15])})
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typs[104] = functype(nil, []*Node{anonfield(typs[17]), anonfield(typs[17])}, []*Node{anonfield(typs[17])})
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typs[105] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[15])})
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typs[106] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[17])})
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typs[107] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[59])})
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typs[108] = functype(nil, []*Node{anonfield(typs[15])}, []*Node{anonfield(typs[13])})
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typs[109] = functype(nil, []*Node{anonfield(typs[17])}, []*Node{anonfield(typs[13])})
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typs[110] = functype(nil, []*Node{anonfield(typs[59])}, []*Node{anonfield(typs[13])})
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typs[111] = functype(nil, []*Node{anonfield(typs[19]), anonfield(typs[19])}, []*Node{anonfield(typs[19])})
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typs[112] = functype(nil, []*Node{anonfield(typs[48])}, nil)
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typs[113] = functype(nil, []*Node{anonfield(typs[48]), anonfield(typs[48])}, nil)
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typs[91] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[80]), anonfield(typs[3])}, nil)
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typs[92] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[77]), anonfield(typs[3]), anonfield(typs[89])}, nil)
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typs[93] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[1]), anonfield(typs[32])}, []*Node{anonfield(typs[32])})
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typs[94] = types.NewSlice(typs[2])
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typs[95] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[32]), anonfield(typs[32])}, []*Node{anonfield(typs[94])})
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typs[96] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[15]), anonfield(typs[15])}, []*Node{anonfield(typs[94])})
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typs[97] = functype(nil, []*Node{anonfield(typs[1]), anonfield(typs[94]), anonfield(typs[32])}, []*Node{anonfield(typs[94])})
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typs[98] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3]), anonfield(typs[48])}, nil)
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typs[99] = functype(nil, []*Node{anonfield(typs[57]), anonfield(typs[48])}, nil)
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typs[100] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3]), anonfield(typs[48])}, []*Node{anonfield(typs[11])})
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typs[101] = functype(nil, []*Node{anonfield(typs[3]), anonfield(typs[3])}, []*Node{anonfield(typs[11])})
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typs[102] = functype(nil, []*Node{anonfield(typs[15]), anonfield(typs[15])}, []*Node{anonfield(typs[15])})
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typs[103] = functype(nil, []*Node{anonfield(typs[17]), anonfield(typs[17])}, []*Node{anonfield(typs[17])})
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typs[104] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[15])})
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typs[105] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[17])})
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typs[106] = functype(nil, []*Node{anonfield(typs[13])}, []*Node{anonfield(typs[59])})
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typs[107] = functype(nil, []*Node{anonfield(typs[15])}, []*Node{anonfield(typs[13])})
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typs[108] = functype(nil, []*Node{anonfield(typs[17])}, []*Node{anonfield(typs[13])})
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typs[109] = functype(nil, []*Node{anonfield(typs[59])}, []*Node{anonfield(typs[13])})
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typs[110] = functype(nil, []*Node{anonfield(typs[19]), anonfield(typs[19])}, []*Node{anonfield(typs[19])})
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typs[111] = functype(nil, []*Node{anonfield(typs[48])}, nil)
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typs[112] = functype(nil, []*Node{anonfield(typs[48]), anonfield(typs[48])}, nil)
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return typs[:]
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}
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@ -145,11 +145,10 @@ func selectnbsend(hchan chan<- any, elem *any) bool
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func selectnbrecv(elem *any, hchan <-chan any) bool
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func selectnbrecv2(elem *any, received *bool, hchan <-chan any) bool
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func newselect(sel *byte, selsize int64, size int32)
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func selectsend(sel *byte, hchan chan<- any, elem *any)
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func selectrecv(sel *byte, hchan <-chan any, elem *any, received *bool)
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func selectdefault(sel *byte)
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func selectgo(sel *byte) int
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func selectsend(cas *byte, hchan chan<- any, elem *any)
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func selectrecv(cas *byte, hchan <-chan any, elem *any, received *bool)
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func selectdefault(cas *byte)
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func selectgo(cas0 *byte, order0 *byte, ncases int) int
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func block()
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func makeslice(typ *byte, len int, cap int) (ary []any)
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@ -60,7 +60,6 @@ func TestIntendedInlining(t *testing.T) {
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"releasem",
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"round",
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"roundupsize",
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"selectsize",
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"stringStructOf",
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"subtract1",
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"subtractb",
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@ -251,22 +251,25 @@ func walkselectcases(cases *Nodes) []*Node {
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// generate sel-struct
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lineno = sellineno
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selv := temp(selecttype(int64(n)))
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selv := temp(types.NewArray(scasetype(), int64(n)))
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r := nod(OAS, selv, nil)
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r = typecheck(r, Etop)
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init = append(init, r)
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var_ := conv(conv(nod(OADDR, selv, nil), types.Types[TUNSAFEPTR]), types.NewPtr(types.Types[TUINT8]))
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r = mkcall("newselect", nil, nil, var_, nodintconst(selv.Type.Width), nodintconst(int64(n)))
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order := temp(types.NewArray(types.Types[TUINT16], 2*int64(n)))
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r = nod(OAS, order, nil)
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r = typecheck(r, Etop)
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init = append(init, r)
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// register cases
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for _, cas := range cases.Slice() {
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for i, cas := range cases.Slice() {
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setlineno(cas)
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init = append(init, cas.Ninit.Slice()...)
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cas.Ninit.Set(nil)
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s := bytePtrToIndex(selv, int64(i))
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var x *Node
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if n := cas.Left; n != nil {
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init = append(init, n.Ninit.Slice()...)
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@ -275,18 +278,18 @@ func walkselectcases(cases *Nodes) []*Node {
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default:
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Fatalf("select %v", n.Op)
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case OSEND:
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// selectsend(sel *byte, hchan *chan any, elem *any)
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x = mkcall1(chanfn("selectsend", 2, n.Left.Type), nil, nil, var_, n.Left, n.Right)
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// selectsend(cas *byte, hchan *chan any, elem *any)
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x = mkcall1(chanfn("selectsend", 2, n.Left.Type), nil, nil, s, n.Left, n.Right)
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case OSELRECV:
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// selectrecv(sel *byte, hchan *chan any, elem *any, received *bool)
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x = mkcall1(chanfn("selectrecv", 2, n.Right.Left.Type), nil, nil, var_, n.Right.Left, n.Left, nodnil())
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// selectrecv(cas *byte, hchan *chan any, elem *any, received *bool)
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x = mkcall1(chanfn("selectrecv", 2, n.Right.Left.Type), nil, nil, s, n.Right.Left, n.Left, nodnil())
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case OSELRECV2:
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// selectrecv(sel *byte, hchan *chan any, elem *any, received *bool)
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x = mkcall1(chanfn("selectrecv", 2, n.Right.Left.Type), nil, nil, var_, n.Right.Left, n.Left, n.List.First())
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// selectrecv(cas *byte, hchan *chan any, elem *any, received *bool)
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x = mkcall1(chanfn("selectrecv", 2, n.Right.Left.Type), nil, nil, s, n.Right.Left, n.Left, n.List.First())
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}
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} else {
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// selectdefault(sel *byte)
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x = mkcall("selectdefault", nil, nil, var_)
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// selectdefault(cas *byte)
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x = mkcall("selectdefault", nil, nil, s)
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}
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init = append(init, x)
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@ -295,12 +298,13 @@ func walkselectcases(cases *Nodes) []*Node {
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// run the select
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lineno = sellineno
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chosen := temp(types.Types[TINT])
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r = nod(OAS, chosen, mkcall("selectgo", types.Types[TINT], nil, var_))
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r = nod(OAS, chosen, mkcall("selectgo", types.Types[TINT], nil, bytePtrToIndex(selv, 0), bytePtrToIndex(order, 0), nodintconst(int64(n))))
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r = typecheck(r, Etop)
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init = append(init, r)
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// selv is no longer alive after selectgo.
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// selv and order are no longer alive after selectgo.
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init = append(init, nod(OVARKILL, selv, nil))
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init = append(init, nod(OVARKILL, order, nil))
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// dispatch cases
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for i, cas := range cases.Slice() {
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@ -319,31 +323,28 @@ func walkselectcases(cases *Nodes) []*Node {
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return init
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}
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// Keep in sync with src/runtime/select.go.
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func selecttype(size int64) *types.Type {
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// TODO(dvyukov): it's possible to generate Scase only once
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// and then cache; and also cache Select per size.
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scase := tostruct([]*Node{
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namedfield("elem", types.NewPtr(types.Types[TUINT8])),
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namedfield("chan", types.NewPtr(types.Types[TUINT8])),
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namedfield("pc", types.Types[TUINTPTR]),
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namedfield("kind", types.Types[TUINT16]),
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namedfield("receivedp", types.NewPtr(types.Types[TUINT8])),
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namedfield("releasetime", types.Types[TUINT64]),
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})
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scase.SetNoalg(true)
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sel := tostruct([]*Node{
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namedfield("tcase", types.Types[TUINT16]),
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namedfield("ncase", types.Types[TUINT16]),
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namedfield("pollorder", types.NewPtr(types.Types[TUINT8])),
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namedfield("lockorder", types.NewPtr(types.Types[TUINT8])),
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namedfield("scase", types.NewArray(scase, size)),
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namedfield("lockorderarr", types.NewArray(types.Types[TUINT16], size)),
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namedfield("pollorderarr", types.NewArray(types.Types[TUINT16], size)),
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})
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sel.SetNoalg(true)
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return sel
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// bytePtrToIndex returns a Node representing "(*byte)(&n[i])".
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func bytePtrToIndex(n *Node, i int64) *Node {
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s := nod(OCONVNOP, nod(OADDR, nod(OINDEX, n, nodintconst(i)), nil), nil)
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s.Type = types.NewPtr(types.Types[TUINT8])
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s = typecheck(s, Erv)
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return s
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}
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var scase *types.Type
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// Keep in sync with src/runtime/select.go.
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func scasetype() *types.Type {
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if scase == nil {
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scase = tostruct([]*Node{
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namedfield("elem", types.NewPtr(types.Types[TUINT8])),
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namedfield("chan", types.NewPtr(types.Types[TUINT8])),
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namedfield("pc", types.Types[TUINTPTR]),
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namedfield("kind", types.Types[TUINT16]),
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namedfield("receivedp", types.NewPtr(types.Types[TUINT8])),
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namedfield("releasetime", types.Types[TUINT64]),
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})
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scase.SetNoalg(true)
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}
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return scase
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}
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@ -7,7 +7,6 @@ package runtime
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// This file contains the implementation of Go select statements.
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import (
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"runtime/internal/sys"
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"unsafe"
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)
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@ -21,20 +20,9 @@ const (
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caseDefault
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)
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// Select statement header.
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// Known to compiler.
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// Changes here must also be made in src/cmd/internal/gc/select.go's selecttype.
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type hselect struct {
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tcase uint16 // total count of scase[]
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ncase uint16 // currently filled scase[]
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pollorder *uint16 // case poll order
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lockorder *uint16 // channel lock order
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scase [1]scase // one per case (in order of appearance)
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}
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// Select case descriptor.
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// Known to compiler.
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// Changes here must also be made in src/cmd/internal/gc/select.go's selecttype.
|
||||
// Changes here must also be made in src/cmd/internal/gc/select.go's scasetype.
|
||||
type scase struct {
|
||||
elem unsafe.Pointer // data element
|
||||
c *hchan // chan
|
||||
@ -49,86 +37,42 @@ var (
|
||||
chanrecvpc = funcPC(chanrecv)
|
||||
)
|
||||
|
||||
func selectsize(size uintptr) uintptr {
|
||||
selsize := unsafe.Sizeof(hselect{}) +
|
||||
(size-1)*unsafe.Sizeof(hselect{}.scase[0]) +
|
||||
size*unsafe.Sizeof(*hselect{}.lockorder) +
|
||||
size*unsafe.Sizeof(*hselect{}.pollorder)
|
||||
return round(selsize, sys.Int64Align)
|
||||
}
|
||||
|
||||
func newselect(sel *hselect, selsize int64, size int32) {
|
||||
if selsize != int64(selectsize(uintptr(size))) {
|
||||
print("runtime: bad select size ", selsize, ", want ", selectsize(uintptr(size)), "\n")
|
||||
throw("bad select size")
|
||||
}
|
||||
sel.tcase = uint16(size)
|
||||
sel.ncase = 0
|
||||
sel.lockorder = (*uint16)(add(unsafe.Pointer(&sel.scase), uintptr(size)*unsafe.Sizeof(hselect{}.scase[0])))
|
||||
sel.pollorder = (*uint16)(add(unsafe.Pointer(sel.lockorder), uintptr(size)*unsafe.Sizeof(*hselect{}.lockorder)))
|
||||
|
||||
if debugSelect {
|
||||
print("newselect s=", sel, " size=", size, "\n")
|
||||
}
|
||||
}
|
||||
|
||||
func selectsend(sel *hselect, c *hchan, elem unsafe.Pointer) {
|
||||
pc := getcallerpc()
|
||||
i := sel.ncase
|
||||
if i >= sel.tcase {
|
||||
throw("selectsend: too many cases")
|
||||
}
|
||||
sel.ncase = i + 1
|
||||
func selectsend(cas *scase, c *hchan, elem unsafe.Pointer) {
|
||||
if c == nil {
|
||||
return
|
||||
}
|
||||
cas := (*scase)(add(unsafe.Pointer(&sel.scase), uintptr(i)*unsafe.Sizeof(sel.scase[0])))
|
||||
cas.pc = pc
|
||||
cas.pc = getcallerpc()
|
||||
cas.c = c
|
||||
cas.kind = caseSend
|
||||
cas.elem = elem
|
||||
|
||||
if debugSelect {
|
||||
print("selectsend s=", sel, " pc=", hex(cas.pc), " chan=", cas.c, "\n")
|
||||
print("selectsend cas=", cas, " pc=", hex(cas.pc), " chan=", cas.c, "\n")
|
||||
}
|
||||
}
|
||||
|
||||
func selectrecv(sel *hselect, c *hchan, elem unsafe.Pointer, received *bool) {
|
||||
pc := getcallerpc()
|
||||
i := sel.ncase
|
||||
if i >= sel.tcase {
|
||||
throw("selectrecv: too many cases")
|
||||
}
|
||||
sel.ncase = i + 1
|
||||
func selectrecv(cas *scase, c *hchan, elem unsafe.Pointer, received *bool) {
|
||||
if c == nil {
|
||||
return
|
||||
}
|
||||
cas := (*scase)(add(unsafe.Pointer(&sel.scase), uintptr(i)*unsafe.Sizeof(sel.scase[0])))
|
||||
cas.pc = pc
|
||||
cas.pc = getcallerpc()
|
||||
cas.c = c
|
||||
cas.kind = caseRecv
|
||||
cas.elem = elem
|
||||
cas.receivedp = received
|
||||
|
||||
if debugSelect {
|
||||
print("selectrecv s=", sel, " pc=", hex(cas.pc), " chan=", cas.c, "\n")
|
||||
print("selectrecv cas=", cas, " pc=", hex(cas.pc), " chan=", cas.c, "\n")
|
||||
}
|
||||
}
|
||||
|
||||
func selectdefault(sel *hselect) {
|
||||
pc := getcallerpc()
|
||||
i := sel.ncase
|
||||
if i >= sel.tcase {
|
||||
throw("selectdefault: too many cases")
|
||||
}
|
||||
sel.ncase = i + 1
|
||||
cas := (*scase)(add(unsafe.Pointer(&sel.scase), uintptr(i)*unsafe.Sizeof(sel.scase[0])))
|
||||
cas.pc = pc
|
||||
func selectdefault(cas *scase) {
|
||||
cas.pc = getcallerpc()
|
||||
cas.c = nil
|
||||
cas.kind = caseDefault
|
||||
|
||||
if debugSelect {
|
||||
print("selectdefault s=", sel, " pc=", hex(cas.pc), "\n")
|
||||
print("selectdefault cas=", cas, " pc=", hex(cas.pc), "\n")
|
||||
}
|
||||
}
|
||||
|
||||
@ -194,26 +138,28 @@ func block() {
|
||||
|
||||
// selectgo implements the select statement.
|
||||
//
|
||||
// *sel is on the current goroutine's stack (regardless of any
|
||||
// escaping in selectgo).
|
||||
// cas0 points to an array of type [ncases]scase, and order0 points to
|
||||
// an array of type [2*ncases]uint16. Both reside on the goroutine's
|
||||
// stack (regardless of any escaping in selectgo).
|
||||
//
|
||||
// selectgo returns the index of the chosen scase, which matches the
|
||||
// ordinal position of its respective select{recv,send,default} call.
|
||||
func selectgo(sel *hselect) int {
|
||||
func selectgo(cas0 *scase, order0 *uint16, ncases int) int {
|
||||
if debugSelect {
|
||||
print("select: sel=", sel, "\n")
|
||||
}
|
||||
if sel.ncase != sel.tcase {
|
||||
throw("selectgo: case count mismatch")
|
||||
print("select: cas0=", cas0, "\n")
|
||||
}
|
||||
|
||||
scaseslice := slice{unsafe.Pointer(&sel.scase), int(sel.ncase), int(sel.ncase)}
|
||||
scases := *(*[]scase)(unsafe.Pointer(&scaseslice))
|
||||
cas1 := (*[1 << 16]scase)(unsafe.Pointer(cas0))
|
||||
order1 := (*[1 << 17]uint16)(unsafe.Pointer(order0))
|
||||
|
||||
scases := cas1[:ncases:ncases]
|
||||
pollorder := order1[:ncases:ncases]
|
||||
lockorder := order1[ncases:][:ncases:ncases]
|
||||
|
||||
var t0 int64
|
||||
if blockprofilerate > 0 {
|
||||
t0 = cputicks()
|
||||
for i := 0; i < int(sel.ncase); i++ {
|
||||
for i := 0; i < ncases; i++ {
|
||||
scases[i].releasetime = -1
|
||||
}
|
||||
}
|
||||
@ -227,9 +173,7 @@ func selectgo(sel *hselect) int {
|
||||
// optimizing (and needing to test).
|
||||
|
||||
// generate permuted order
|
||||
pollslice := slice{unsafe.Pointer(sel.pollorder), int(sel.ncase), int(sel.ncase)}
|
||||
pollorder := *(*[]uint16)(unsafe.Pointer(&pollslice))
|
||||
for i := 1; i < int(sel.ncase); i++ {
|
||||
for i := 1; i < ncases; i++ {
|
||||
j := fastrandn(uint32(i + 1))
|
||||
pollorder[i] = pollorder[j]
|
||||
pollorder[j] = uint16(i)
|
||||
@ -237,9 +181,7 @@ func selectgo(sel *hselect) int {
|
||||
|
||||
// sort the cases by Hchan address to get the locking order.
|
||||
// simple heap sort, to guarantee n log n time and constant stack footprint.
|
||||
lockslice := slice{unsafe.Pointer(sel.lockorder), int(sel.ncase), int(sel.ncase)}
|
||||
lockorder := *(*[]uint16)(unsafe.Pointer(&lockslice))
|
||||
for i := 0; i < int(sel.ncase); i++ {
|
||||
for i := 0; i < ncases; i++ {
|
||||
j := i
|
||||
// Start with the pollorder to permute cases on the same channel.
|
||||
c := scases[pollorder[i]].c
|
||||
@ -250,7 +192,7 @@ func selectgo(sel *hselect) int {
|
||||
}
|
||||
lockorder[j] = pollorder[i]
|
||||
}
|
||||
for i := int(sel.ncase) - 1; i >= 0; i-- {
|
||||
for i := ncases - 1; i >= 0; i-- {
|
||||
o := lockorder[i]
|
||||
c := scases[o].c
|
||||
lockorder[i] = lockorder[0]
|
||||
@ -273,7 +215,7 @@ func selectgo(sel *hselect) int {
|
||||
lockorder[j] = o
|
||||
}
|
||||
/*
|
||||
for i := 0; i+1 < int(sel.ncase); i++ {
|
||||
for i := 0; i+1 < ncases; i++ {
|
||||
if scases[lockorder[i]].c.sortkey() > scases[lockorder[i+1]].c.sortkey() {
|
||||
print("i=", i, " x=", lockorder[i], " y=", lockorder[i+1], "\n")
|
||||
throw("select: broken sort")
|
||||
@ -301,7 +243,7 @@ loop:
|
||||
var dfl *scase
|
||||
var casi int
|
||||
var cas *scase
|
||||
for i := 0; i < int(sel.ncase); i++ {
|
||||
for i := 0; i < ncases; i++ {
|
||||
casi = int(pollorder[i])
|
||||
cas = &scases[casi]
|
||||
c = cas.c
|
||||
@ -454,7 +396,7 @@ loop:
|
||||
c = cas.c
|
||||
|
||||
if debugSelect {
|
||||
print("wait-return: sel=", sel, " c=", c, " cas=", cas, " kind=", cas.kind, "\n")
|
||||
print("wait-return: cas0=", cas0, " c=", c, " cas=", cas, " kind=", cas.kind, "\n")
|
||||
}
|
||||
|
||||
if cas.kind == caseRecv && cas.receivedp != nil {
|
||||
@ -530,7 +472,7 @@ recv:
|
||||
// can receive from sleeping sender (sg)
|
||||
recv(c, sg, cas.elem, func() { selunlock(scases, lockorder) }, 2)
|
||||
if debugSelect {
|
||||
print("syncrecv: sel=", sel, " c=", c, "\n")
|
||||
print("syncrecv: cas0=", cas0, " c=", c, "\n")
|
||||
}
|
||||
if cas.receivedp != nil {
|
||||
*cas.receivedp = true
|
||||
@ -561,7 +503,7 @@ send:
|
||||
}
|
||||
send(c, sg, cas.elem, func() { selunlock(scases, lockorder) }, 2)
|
||||
if debugSelect {
|
||||
print("syncsend: sel=", sel, " c=", c, "\n")
|
||||
print("syncsend: cas0=", cas0, " c=", c, "\n")
|
||||
}
|
||||
goto retc
|
||||
|
||||
@ -604,24 +546,25 @@ const (
|
||||
|
||||
//go:linkname reflect_rselect reflect.rselect
|
||||
func reflect_rselect(cases []runtimeSelect) (chosen int, recvOK bool) {
|
||||
// flagNoScan is safe here, because all objects are also referenced from cases.
|
||||
size := selectsize(uintptr(len(cases)))
|
||||
sel := (*hselect)(mallocgc(size, nil, true))
|
||||
newselect(sel, int64(size), int32(len(cases)))
|
||||
if len(cases) == 0 {
|
||||
block()
|
||||
}
|
||||
sel := make([]scase, len(cases))
|
||||
order := make([]uint16, 2*len(cases))
|
||||
r := new(bool)
|
||||
for i := range cases {
|
||||
rc := &cases[i]
|
||||
switch rc.dir {
|
||||
case selectDefault:
|
||||
selectdefault(sel)
|
||||
selectdefault(&sel[i])
|
||||
case selectSend:
|
||||
selectsend(sel, rc.ch, rc.val)
|
||||
selectsend(&sel[i], rc.ch, rc.val)
|
||||
case selectRecv:
|
||||
selectrecv(sel, rc.ch, rc.val, r)
|
||||
selectrecv(&sel[i], rc.ch, rc.val, r)
|
||||
}
|
||||
}
|
||||
|
||||
chosen = selectgo(sel)
|
||||
chosen = selectgo(&sel[0], &order[0], len(cases))
|
||||
recvOK = *r
|
||||
return
|
||||
}
|
||||
|
||||
@ -163,7 +163,7 @@ var b bool
|
||||
|
||||
// this used to have a spurious "live at entry to f11a: ~r0"
|
||||
func f11a() *int {
|
||||
select { // ERROR "live at call to newselect: .autotmp_[0-9]+$" "live at call to selectgo: .autotmp_[0-9]+$"
|
||||
select { // ERROR "live at call to selectgo: .autotmp_[0-9]+$"
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+$"
|
||||
return nil
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+$"
|
||||
@ -178,7 +178,7 @@ func f11b() *int {
|
||||
// get to the bottom of the function.
|
||||
// This used to have a spurious "live at call to printint: p".
|
||||
printint(1) // nothing live here!
|
||||
select { // ERROR "live at call to newselect: .autotmp_[0-9]+$" "live at call to selectgo: .autotmp_[0-9]+$"
|
||||
select { // ERROR "live at call to selectgo: .autotmp_[0-9]+$"
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+$"
|
||||
return nil
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+$"
|
||||
@ -198,7 +198,7 @@ func f11c() *int {
|
||||
// Unlike previous, the cases in this select fall through,
|
||||
// so we can get to the println, so p is not dead.
|
||||
printint(1) // ERROR "live at call to printint: p$"
|
||||
select { // ERROR "live at call to newselect: .autotmp_[0-9]+ p$" "live at call to selectgo: .autotmp_[0-9]+ p$"
|
||||
select { // ERROR "live at call to selectgo: .autotmp_[0-9]+ p$"
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+ p$"
|
||||
case <-c: // ERROR "live at call to selectrecv: .autotmp_[0-9]+ p$"
|
||||
}
|
||||
@ -589,7 +589,7 @@ func f38(b bool) {
|
||||
// we care that the println lines have no live variables
|
||||
// and therefore no output.
|
||||
if b {
|
||||
select { // ERROR "live at call to newselect:( .autotmp_[0-9]+)+$" "live at call to selectgo:( .autotmp_[0-9]+)+$"
|
||||
select { // ERROR "live at call to selectgo:( .autotmp_[0-9]+)+$"
|
||||
case <-fc38(): // ERROR "live at call to selectrecv:( .autotmp_[0-9]+)+$"
|
||||
printnl()
|
||||
case fc38() <- *fi38(1): // ERROR "live at call to fc38:( .autotmp_[0-9]+)+$" "live at call to fi38:( .autotmp_[0-9]+)+$" "live at call to selectsend:( .autotmp_[0-9]+)+$"
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user