8028471: PPC64 (part 215): opto: Extend ImplicitNullCheck optimization.
Summary: Fixed Implicit NULL check optimization for AIX, where the page at address '0' is only write-protected.
Reviewed-by: kvn
/* * Copyright (c) 2004, 2011, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *//* * This source code is provided to illustrate the usage of a given feature * or technique and has been deliberately simplified. Additional steps * required for a production-quality application, such as security checks, * input validation and proper error handling, might not be present in * this sample code. */#ifndef HPROF_BLOCKS_H#define HPROF_BLOCKS_Htypedef struct BlockHeader { struct BlockHeader *next; int bytes_left; int next_pos;} BlockHeader;typedef struct Blocks { BlockHeader *first_block; /* Pointer to first BlockHeader */ BlockHeader *current_block; /* Pointer to current BlockHeader */ int alignment; /* Data alignment, 1, 2, 4, 8, 16 */ int elem_size; /* Size in bytes, ==1 means variable sizes */ int population; /* Number of elements to allow for per Block */} Blocks;Blocks * blocks_init(int alignment, int elem_size, int population);void * blocks_alloc(Blocks *blocks, int nbytes);void blocks_term(Blocks *blocks);#endif