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25 lines
665 B
Go
25 lines
665 B
Go
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// asmcheck
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// Copyright 2018 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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package codegen
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var gx, gy int
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// Test to make sure that (CMPQ (ANDQ x y) [0]) does not get rewritten to
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// (TESTQ x y) if the ANDQ has other uses. If that rewrite happens, then one
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// of the args of the ANDQ needs to be saved so it can be used as the arg to TESTQ.
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func andWithUse(x, y int) int {
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// Load x,y into registers, so those MOVQ will not appear at the z := x&y line.
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gx, gy = x, y
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// amd64:-"MOVQ"
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z := x & y
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if z == 0 {
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return 77
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}
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// use z by returning it
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return z
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}
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