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// Copyright 2012 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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// Test, using compiler diagnostic flags, that bounds check elimination
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// is eliminating the correct checks.
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// Most things need checks.
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// Unsigned 8-bit numbers don't need checks for len >= 2⁸.
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use(a1k[ui8]) // ERROR "index bounds check elided"
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use(a100k[ui8]) // ERROR "index bounds check elided"
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use(p1k[ui8]) // ERROR "index bounds check elided"
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use(p100k[ui8]) // ERROR "index bounds check elided"
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// Unsigned 16-bit numbers don't need checks for len >= 2¹⁶.
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use(a100k[ui16]) // ERROR "index bounds check elided"
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use(p100k[ui16]) // ERROR "index bounds check elided"
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// Mod truncates the maximum value to one less than the argument,
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// but signed mod can be negative, so only unsigned mod counts.
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use(a1k[ui%999]) // ERROR "index bounds check elided"
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use(a100k[ui%999]) // ERROR "index bounds check elided"
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use(p1k[ui%999]) // ERROR "index bounds check elided"
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use(p100k[ui%999]) // ERROR "index bounds check elided"
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use(a1k[ui%1000]) // ERROR "index bounds check elided"
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use(a100k[ui%1000]) // ERROR "index bounds check elided"
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use(p1k[ui%1000]) // ERROR "index bounds check elided"
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use(p100k[ui%1000]) // ERROR "index bounds check elided"
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use(a100k[ui%1001]) // ERROR "index bounds check elided"
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use(p100k[ui%1001]) // ERROR "index bounds check elided"
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// Bitwise and truncates the maximum value to the mask value.
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// The result (for a positive mask) cannot be negative, so elision
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// applies to both signed and unsigned indexes.
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use(a1k[i&999]) // ERROR "index bounds check elided"
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use(a100k[i&999]) // ERROR "index bounds check elided"
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use(p1k[i&999]) // ERROR "index bounds check elided"
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use(p100k[i&999]) // ERROR "index bounds check elided"
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use(a1k[ui&999]) // ERROR "index bounds check elided"
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use(a100k[ui&999]) // ERROR "index bounds check elided"
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use(p1k[ui&999]) // ERROR "index bounds check elided"
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use(p100k[ui&999]) // ERROR "index bounds check elided"
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use(a100k[i&1000]) // ERROR "index bounds check elided"
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use(p100k[i&1000]) // ERROR "index bounds check elided"
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use(a100k[ui&1000]) // ERROR "index bounds check elided"
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use(p100k[ui&1000]) // ERROR "index bounds check elided"
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// Right shift cuts the effective number of bits in the index,
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// but only for unsigned (signed stays negative).
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use(a100k[ui32>>22]) // ERROR "index bounds check elided"
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use(p100k[ui32>>22]) // ERROR "index bounds check elided"
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use(a1k[ui32>>23]) // ERROR "index bounds check elided"
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use(a100k[ui32>>23]) // ERROR "index bounds check elided"
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use(p1k[ui32>>23]) // ERROR "index bounds check elided"
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use(p100k[ui32>>23]) // ERROR "index bounds check elided"
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// Division cuts the range like right shift does.