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540f8c2b50
Following CL 357330, use jump tables on ARM64. name old time/op new time/op delta Switch8Predictable-4 3.41ns ± 0% 3.21ns ± 0% ~ (p=0.079 n=4+5) Switch8Unpredictable-4 12.0ns ± 0% 9.5ns ± 0% -21.17% (p=0.000 n=5+4) Switch32Predictable-4 3.06ns ± 0% 2.82ns ± 0% -7.78% (p=0.008 n=5+5) Switch32Unpredictable-4 13.3ns ± 0% 9.5ns ± 0% -28.87% (p=0.016 n=4+5) SwitchStringPredictable-4 3.71ns ± 0% 3.21ns ± 0% -13.43% (p=0.000 n=5+4) SwitchStringUnpredictable-4 14.8ns ± 0% 15.1ns ± 0% +2.37% (p=0.008 n=5+5) Change-Id: Ia0b85df7ca9273cf70c05eb957225c6e61822fa6 Reviewed-on: https://go-review.googlesource.com/c/go/+/403979 TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Run-TryBot: Cherry Mui <cherryyz@google.com> Reviewed-by: David Chase <drchase@google.com>
74 lines
1.1 KiB
Go
74 lines
1.1 KiB
Go
// asmcheck
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// Copyright 2019 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// These tests check code generation of switch statements.
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package codegen
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// see issue 33934
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func f(x string) int {
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// amd64:-`cmpstring`
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switch x {
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case "":
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return -1
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case "1", "2", "3":
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return -2
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default:
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return -3
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}
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}
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// use jump tables for 8+ int cases
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func square(x int) int {
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// amd64:`JMP\s\(.*\)\(.*\)$`
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// arm64:`MOVD\s\(R.*\)\(R.*<<3\)`,`JMP\s\(R.*\)$`
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switch x {
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case 1:
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return 1
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case 2:
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return 4
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case 3:
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return 9
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case 4:
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return 16
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case 5:
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return 25
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case 6:
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return 36
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case 7:
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return 49
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case 8:
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return 64
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default:
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return x * x
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}
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}
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// use jump tables for 8+ string lengths
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func length(x string) int {
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// amd64:`JMP\s\(.*\)\(.*\)$`
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// arm64:`MOVD\s\(R.*\)\(R.*<<3\)`,`JMP\s\(R.*\)$`
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switch x {
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case "a":
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return 1
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case "bb":
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return 2
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case "ccc":
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return 3
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case "dddd":
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return 4
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case "eeeee":
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return 5
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case "ffffff":
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return 6
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case "ggggggg":
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return 7
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case "hhhhhhhh":
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return 8
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default:
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return len(x)
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}
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}
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