/*****************************************************************************/ /* */ /* coptstore.h */ /* */ /* Optimize stores */ /* */ /* */ /* */ /* (C) 2002-2006, Ullrich von Bassewitz */ /* Roemerstrasse 52 */ /* D-70794 Filderstadt */ /* EMail: uz@cc65.org */ /* */ /* */ /* This software is provided 'as-is', without any expressed or implied */ /* warranty. In no event will the authors be held liable for any damages */ /* arising from the use of this software. */ /* */ /* Permission is granted to anyone to use this software for any purpose, */ /* including commercial applications, and to alter it and redistribute it */ /* freely, subject to the following restrictions: */ /* */ /* 1. The origin of this software must not be misrepresented; you must not */ /* claim that you wrote the original software. If you use this software */ /* in a product, an acknowledgment in the product documentation would be */ /* appreciated but is not required. */ /* 2. Altered source versions must be plainly marked as such, and must not */ /* be misrepresented as being the original software. */ /* 3. This notice may not be removed or altered from any source */ /* distribution. */ /* */ /*****************************************************************************/ #ifndef COPTSTORE_H #define COPTSTORE_H /* cc65 */ #include "codeseg.h" /*****************************************************************************/ /* Code */ /*****************************************************************************/ unsigned OptStore1 (CodeSeg* S); /* Search for the sequence ** ** ldy #n ** jsr staxysp ** ldy #n+1 ** jsr ldaxysp ** ** and remove the useless load, provided that the next insn doesn't use flags ** from the load. */ unsigned OptStore2 (CodeSeg* S); /* Search for a call to staxysp. If the ax register is not used later, and ** the value is constant, just use the A register and store directly into the ** stack. */ unsigned OptStore3 (CodeSeg* S); /* Search for a call to steaxysp. If the eax register is not used later, and ** the value is constant, just use the A register and store directly into the ** stack. */ unsigned OptStore4 (CodeSeg* S); /* Search for the sequence ** ** sta xx ** stx yy ** lda xx ** ldx yy ** ** and remove the useless load, provided that the next insn doesn't use flags ** from the load. */ unsigned OptStore5 (CodeSeg* S); /* Search for the sequence ** ** lda foo ** ldx bar ** sta something ** stx something-else ** ** and replace it by ** ** lda foo ** sta something ** lda bar ** sta something-else ** ** if X is not used later. This replacement doesn't save any cycles or bytes, ** but it keeps the value of X, which may be reused later. */ /* End of coptstore.h */ #endif