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c570f0eda2
This shows up in a few crypto functions, and other assorted places. Change-Id: I5a7f4c25ddd4a6499dc295ef693b9fe43d2448ab Reviewed-on: https://go-review.googlesource.com/c/go/+/404057 Run-TryBot: Paul Murphy <murp@ibm.com> TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Russ Cox <rsc@golang.org>
33 lines
815 B
Go
33 lines
815 B
Go
// 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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// Verify (OR x (NOT y)) rewrites to (ORN x y) where supported
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func ornot(x, y int) int {
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// ppc64:"ORN"
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// ppc64le:"ORN"
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z := x | ^y
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return z
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}
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