mirror of
https://github.com/cc65/cc65.git
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2082 lines
63 KiB
C
2082 lines
63 KiB
C
/*****************************************************************************/
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/* */
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/* coptstop.c */
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/* */
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/* Optimize operations that take operands via the stack */
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/* */
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/* */
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/* */
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/* (C) 2001-2013, Ullrich von Bassewitz */
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/* Roemerstrasse 52 */
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/* D-70794 Filderstadt */
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/* EMail: uz@cc65.org */
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/* */
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/* */
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/* This software is provided 'as-is', without any expressed or implied */
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/* warranty. In no event will the authors be held liable for any damages */
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/* arising from the use of this software. */
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/* */
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/* Permission is granted to anyone to use this software for any purpose, */
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/* including commercial applications, and to alter it and redistribute it */
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/* freely, subject to the following restrictions: */
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/* */
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/* 1. The origin of this software must not be misrepresented; you must not */
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/* claim that you wrote the original software. If you use this software */
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/* in a product, an acknowledgment in the product documentation would be */
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/* appreciated but is not required. */
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/* 2. Altered source versions must be plainly marked as such, and must not */
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/* be misrepresented as being the original software. */
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/* 3. This notice may not be removed or altered from any source */
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/* distribution. */
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/* */
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/*****************************************************************************/
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#include <stdlib.h>
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/* common */
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#include "chartype.h"
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/* cc65 */
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#include "codeent.h"
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#include "codeinfo.h"
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#include "coptstop.h"
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#include "error.h"
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/*****************************************************************************/
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/* Load tracking data */
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/*****************************************************************************/
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/* LoadRegInfo flags set by DirectOp */
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typedef enum {
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LI_NONE = 0x00,
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LI_DIRECT = 0x01, /* Direct op may be used */
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LI_RELOAD_Y = 0x02, /* Reload index register Y */
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LI_REMOVE = 0x04, /* Load may be removed */
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LI_DONT_REMOVE = 0x08, /* Load may not be removed */
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LI_DUP_LOAD = 0x10, /* Duplicate load */
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} LI_FLAGS;
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/* Structure that tells us how to load the lhs values */
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typedef struct LoadRegInfo LoadRegInfo;
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struct LoadRegInfo {
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LI_FLAGS Flags; /* Tells us how to load */
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int LoadIndex; /* Index of load insn, -1 if invalid */
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CodeEntry* LoadEntry; /* The actual entry, 0 if invalid */
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int XferIndex; /* Index of transfer insn */
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CodeEntry* XferEntry; /* The actual transfer entry */
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int Offs; /* Stack offset if data is on stack */
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};
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/* Now combined for both registers */
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typedef struct LoadInfo LoadInfo;
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struct LoadInfo {
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LoadRegInfo A; /* Info for A register */
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LoadRegInfo X; /* Info for X register */
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LoadRegInfo Y; /* Info for Y register */
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};
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/*****************************************************************************/
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/* Data */
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/*****************************************************************************/
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/* Flags for the functions */
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typedef enum {
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OP_NONE = 0x00, /* Nothing special */
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OP_A_KNOWN = 0x01, /* Value of A must be known */
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OP_X_ZERO = 0x02, /* X must be zero */
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OP_LHS_LOAD = 0x04, /* Must have load insns for LHS */
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OP_LHS_LOAD_DIRECT = 0x0C, /* Must have direct load insn for LHS */
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OP_RHS_LOAD = 0x10, /* Must have load insns for RHS */
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OP_RHS_LOAD_DIRECT = 0x30, /* Must have direct load insn for RHS */
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} OP_FLAGS;
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/* Structure forward decl */
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typedef struct StackOpData StackOpData;
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/* Structure that describes an optimizer subfunction for a specific op */
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typedef unsigned (*OptFunc) (StackOpData* D);
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typedef struct OptFuncDesc OptFuncDesc;
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struct OptFuncDesc {
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const char* Name; /* Name of the replaced runtime function */
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OptFunc Func; /* Function pointer */
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unsigned UnusedRegs; /* Regs that must not be used later */
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OP_FLAGS Flags; /* Flags */
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};
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/* Structure that holds the needed data */
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struct StackOpData {
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CodeSeg* Code; /* Pointer to code segment */
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unsigned Flags; /* Flags to remember things */
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/* Pointer to optimizer subfunction description */
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const OptFuncDesc* OptFunc;
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/* ZP register usage inside the sequence */
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unsigned UsedRegs;
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/* Register load information for lhs and rhs */
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LoadInfo Lhs;
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LoadInfo Rhs;
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/* Several indices of insns in the code segment */
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int PushIndex; /* Index of call to pushax in codeseg */
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int OpIndex; /* Index of actual operation */
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/* Pointers to insns in the code segment */
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CodeEntry* PrevEntry; /* Entry before the call to pushax */
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CodeEntry* PushEntry; /* Pointer to entry with call to pushax */
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CodeEntry* OpEntry; /* Pointer to entry with op */
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CodeEntry* NextEntry; /* Entry after the op */
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const char* ZPLo; /* Lo byte of zero page loc to use */
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const char* ZPHi; /* Hi byte of zero page loc to use */
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unsigned IP; /* Insertion point used by some routines */
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};
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/*****************************************************************************/
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/* Load tracking code */
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/*****************************************************************************/
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static void ClearLoadRegInfo (LoadRegInfo* RI)
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/* Clear a LoadRegInfo struct */
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{
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RI->Flags = LI_NONE;
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RI->LoadIndex = -1;
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RI->XferIndex = -1;
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RI->Offs = 0;
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}
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static void FinalizeLoadRegInfo (LoadRegInfo* RI, CodeSeg* S)
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/* Prepare a LoadRegInfo struct for use */
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{
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/* Get the entries */
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if (RI->LoadIndex >= 0) {
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RI->LoadEntry = CS_GetEntry (S, RI->LoadIndex);
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} else {
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RI->LoadEntry = 0;
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}
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if (RI->XferIndex >= 0) {
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RI->XferEntry = CS_GetEntry (S, RI->XferIndex);
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} else {
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RI->XferEntry = 0;
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}
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}
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static void ClearLoadInfo (LoadInfo* LI)
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/* Clear a LoadInfo struct */
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{
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ClearLoadRegInfo (&LI->A);
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ClearLoadRegInfo (&LI->X);
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ClearLoadRegInfo (&LI->Y);
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}
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static void AdjustLoadRegInfo (LoadRegInfo* RI, int Index, int Change)
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/* Adjust a load register info struct after deleting or inserting an entry
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** with a given index
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*/
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{
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CHECK (abs (Change) == 1);
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if (Change < 0) {
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/* Deletion */
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if (Index < RI->LoadIndex) {
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--RI->LoadIndex;
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} else if (Index == RI->LoadIndex) {
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/* Has been removed */
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RI->LoadIndex = -1;
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RI->LoadEntry = 0;
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}
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if (Index < RI->XferIndex) {
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--RI->XferIndex;
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} else if (Index == RI->XferIndex) {
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/* Has been removed */
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RI->XferIndex = -1;
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RI->XferEntry = 0;
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}
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} else {
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/* Insertion */
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if (Index <= RI->LoadIndex) {
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++RI->LoadIndex;
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}
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if (Index <= RI->XferIndex) {
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++RI->XferIndex;
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}
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}
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}
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static void FinalizeLoadInfo (LoadInfo* LI, CodeSeg* S)
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/* Prepare a LoadInfo struct for use */
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{
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/* Get the entries */
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FinalizeLoadRegInfo (&LI->A, S);
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FinalizeLoadRegInfo (&LI->X, S);
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FinalizeLoadRegInfo (&LI->Y, S);
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}
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static void AdjustLoadInfo (LoadInfo* LI, int Index, int Change)
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/* Adjust a load info struct after deleting entry with a given index */
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{
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AdjustLoadRegInfo (&LI->A, Index, Change);
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AdjustLoadRegInfo (&LI->X, Index, Change);
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AdjustLoadRegInfo (&LI->Y, Index, Change);
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}
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static void HonourUseAndChg (LoadRegInfo* RI, unsigned Reg, const CodeEntry* E)
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/* Honour use and change flags for an instruction */
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{
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if (E->Chg & Reg) {
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ClearLoadRegInfo (RI);
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} else if ((E->Use & Reg) && RI->LoadIndex >= 0) {
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RI->Flags |= LI_DONT_REMOVE;
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}
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}
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static void TrackLoads (LoadInfo* LI, CodeEntry* E, int I)
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/* Track loads for a code entry */
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{
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if (E->Info & OF_LOAD) {
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LoadRegInfo* RI = 0;
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/* Determine, which register was loaded */
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if (E->Chg & REG_A) {
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RI = &LI->A;
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} else if (E->Chg & REG_X) {
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RI = &LI->X;
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} else if (E->Chg & REG_Y) {
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RI = &LI->Y;
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}
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CHECK (RI != 0);
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/* If we had a load or xfer op before, this is a duplicate load which
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** can cause problems if it encountered between the pushax and the op,
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** so remember it.
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*/
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if (RI->LoadIndex >= 0 || RI->XferIndex >= 0) {
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RI->Flags |= LI_DUP_LOAD;
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}
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/* Remember the load */
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RI->LoadIndex = I;
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RI->XferIndex = -1;
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/* Set load flags */
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RI->Flags &= ~(LI_DIRECT | LI_RELOAD_Y);
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if (E->AM == AM65_IMM || E->AM == AM65_ZP || E->AM == AM65_ABS) {
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/* These insns are all ok and replaceable */
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RI->Flags |= LI_DIRECT;
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} else if (E->AM == AM65_ZP_INDY &&
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RegValIsKnown (E->RI->In.RegY) &&
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strcmp (E->Arg, "sp") == 0) {
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/* A load from the stack with known offset is also ok, but in this
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** case we must reload the index register later. Please note that
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** a load indirect via other zero page locations is not ok, since
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** these locations may change between the push and the actual
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** operation.
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*/
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RI->Offs = (unsigned char) E->RI->In.RegY;
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RI->Flags |= (LI_DIRECT | LI_RELOAD_Y);
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}
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} else if (E->Info & OF_XFR) {
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/* Determine source and target of the transfer and handle the TSX insn */
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LoadRegInfo* Src;
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LoadRegInfo* Tgt;
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switch (E->OPC) {
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case OP65_TAX: Src = &LI->A; Tgt = &LI->X; break;
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case OP65_TAY: Src = &LI->A; Tgt = &LI->Y; break;
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case OP65_TXA: Src = &LI->X; Tgt = &LI->A; break;
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case OP65_TYA: Src = &LI->Y; Tgt = &LI->A; break;
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case OP65_TSX: ClearLoadRegInfo (&LI->X); return;
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case OP65_TXS: return;
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default: Internal ("Unknown XFR insn in TrackLoads");
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}
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/* If we had a load or xfer op before, this is a duplicate load which
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** can cause problems if it encountered between the pushax and the op,
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** so remember it.
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*/
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if (Tgt->LoadIndex >= 0 || Tgt->XferIndex >= 0) {
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Tgt->Flags |= LI_DUP_LOAD;
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}
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/* Transfer the data */
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Tgt->LoadIndex = Src->LoadIndex;
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Tgt->XferIndex = I;
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Tgt->Offs = Src->Offs;
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Tgt->Flags &= ~(LI_DIRECT | LI_RELOAD_Y);
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Tgt->Flags |= Src->Flags & (LI_DIRECT | LI_RELOAD_Y);
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} else if (CE_IsCallTo (E, "ldaxysp") && RegValIsKnown (E->RI->In.RegY)) {
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/* If we had a load or xfer op before, this is a duplicate load which
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** can cause problems if it encountered between the pushax and the op,
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** so remember it for both registers involved.
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*/
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if (LI->A.LoadIndex >= 0 || LI->A.XferIndex >= 0) {
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LI->A.Flags |= LI_DUP_LOAD;
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}
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if (LI->X.LoadIndex >= 0 || LI->X.XferIndex >= 0) {
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LI->X.Flags |= LI_DUP_LOAD;
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}
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/* Both registers set, Y changed */
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LI->A.LoadIndex = I;
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LI->A.XferIndex = -1;
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LI->A.Flags |= (LI_DIRECT | LI_RELOAD_Y);
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LI->A.Offs = (unsigned char) E->RI->In.RegY - 1;
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LI->X.LoadIndex = I;
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LI->X.XferIndex = -1;
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LI->X.Flags |= (LI_DIRECT | LI_RELOAD_Y);
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LI->X.Offs = (unsigned char) E->RI->In.RegY;
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ClearLoadRegInfo (&LI->Y);
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} else {
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HonourUseAndChg (&LI->A, REG_A, E);
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HonourUseAndChg (&LI->X, REG_X, E);
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HonourUseAndChg (&LI->Y, REG_Y, E);
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}
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}
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/*****************************************************************************/
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/* Helpers */
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/*****************************************************************************/
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static void InsertEntry (StackOpData* D, CodeEntry* E, int Index)
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/* Insert a new entry. Depending on Index, D->PushIndex and D->OpIndex will
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** be adjusted by this function.
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*/
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{
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/* Insert the entry into the code segment */
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CS_InsertEntry (D->Code, E, Index);
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/* Adjust register loads if necessary */
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AdjustLoadInfo (&D->Lhs, Index, 1);
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AdjustLoadInfo (&D->Rhs, Index, 1);
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/* Adjust the indices if necessary */
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if (D->PushEntry && Index <= D->PushIndex) {
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++D->PushIndex;
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}
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if (D->OpEntry && Index <= D->OpIndex) {
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++D->OpIndex;
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}
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}
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static void DelEntry (StackOpData* D, int Index)
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/* Delete an entry. Depending on Index, D->PushIndex and D->OpIndex will be
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** adjusted by this function, and PushEntry/OpEntry may get invalidated.
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*/
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{
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/* Delete the entry from the code segment */
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CS_DelEntry (D->Code, Index);
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/* Adjust register loads if necessary */
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AdjustLoadInfo (&D->Lhs, Index, -1);
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AdjustLoadInfo (&D->Rhs, Index, -1);
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/* Adjust the other indices if necessary */
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if (Index < D->PushIndex) {
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--D->PushIndex;
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} else if (Index == D->PushIndex) {
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D->PushEntry = 0;
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}
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if (Index < D->OpIndex) {
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--D->OpIndex;
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} else if (Index == D->OpIndex) {
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D->OpEntry = 0;
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}
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}
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static void AdjustStackOffset (StackOpData* D, unsigned Offs)
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/* Adjust the offset for all stack accesses in the range PushIndex to OpIndex.
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** OpIndex is adjusted according to the insertions.
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*/
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{
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/* Walk over all entries */
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int I = D->PushIndex + 1;
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while (I < D->OpIndex) {
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CodeEntry* E = CS_GetEntry (D->Code, I);
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int NeedCorrection = 0;
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if ((E->Use & REG_SP) != 0) {
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/* Check for some things that should not happen */
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CHECK (E->AM == AM65_ZP_INDY || E->RI->In.RegY >= (short) Offs);
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CHECK (strcmp (E->Arg, "sp") == 0);
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/* We need to correct this one */
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NeedCorrection = 1;
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} else if (CE_IsCallTo (E, "ldaxysp")) {
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/* We need to correct this one */
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NeedCorrection = 1;
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}
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if (NeedCorrection) {
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/* Get the code entry before this one. If it's a LDY, adjust the
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** value.
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*/
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CodeEntry* P = CS_GetPrevEntry (D->Code, I);
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if (P && P->OPC == OP65_LDY && CE_IsConstImm (P)) {
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/* The Y load is just before the stack access, adjust it */
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CE_SetNumArg (P, P->Num - Offs);
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} else {
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/* Insert a new load instruction before the stack access */
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const char* Arg = MakeHexArg (E->RI->In.RegY - Offs);
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CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
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InsertEntry (D, X, I++);
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}
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/* If we need the value of Y later, be sure to reload it */
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if (RegYUsed (D->Code, I+1)) {
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const char* Arg = MakeHexArg (E->RI->In.RegY);
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CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
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InsertEntry (D, X, I+1);
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/* Skip this instruction in the next round */
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++I;
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}
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}
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/* Next entry */
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++I;
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}
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/* If we have rhs load insns that load from stack, we'll have to adjust
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** the offsets for these also.
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*/
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if (D->Rhs.A.Flags & LI_RELOAD_Y) {
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D->Rhs.A.Offs -= Offs;
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}
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if (D->Rhs.X.Flags & LI_RELOAD_Y) {
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D->Rhs.X.Offs -= Offs;
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}
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}
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static void AddStoreA (StackOpData* D)
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/* Add a store to zero page after the push insn */
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{
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CodeEntry* X = NewCodeEntry (OP65_STA, AM65_ZP, D->ZPLo, 0, D->PushEntry->LI);
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InsertEntry (D, X, D->PushIndex+1);
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}
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static void AddStoreX (StackOpData* D)
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/* Add a store to zero page after the push insn */
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{
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CodeEntry* X = NewCodeEntry (OP65_STX, AM65_ZP, D->ZPHi, 0, D->PushEntry->LI);
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InsertEntry (D, X, D->PushIndex+1);
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}
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static void ReplacePushByStore (StackOpData* D)
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/* Replace the call to the push subroutine by a store into the zero page
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** location (actually, the push is not replaced, because we need it for
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** later, but the name is still ok since the push will get removed at the
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** end of each routine).
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*/
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{
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/* Store the value into the zeropage instead of pushing it. Check high
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** byte first so that the store is later in A/X order.
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*/
|
|
if ((D->Lhs.X.Flags & LI_DIRECT) == 0) {
|
|
AddStoreX (D);
|
|
}
|
|
if ((D->Lhs.A.Flags & LI_DIRECT) == 0) {
|
|
AddStoreA (D);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void AddOpLow (StackOpData* D, opc_t OPC, LoadInfo* LI)
|
|
/* Add an op for the low byte of an operator. This function honours the
|
|
** OP_DIRECT and OP_RELOAD_Y flags and generates the necessary instructions.
|
|
** All code is inserted at the current insertion point.
|
|
*/
|
|
{
|
|
CodeEntry* X;
|
|
|
|
if ((LI->A.Flags & LI_DIRECT) != 0) {
|
|
/* Op with a variable location. If the location is on the stack, we
|
|
** need to reload the Y register.
|
|
*/
|
|
if ((LI->A.Flags & LI_RELOAD_Y) == 0) {
|
|
|
|
/* opc ... */
|
|
CodeEntry* LoadA = LI->A.LoadEntry;
|
|
X = NewCodeEntry (OPC, LoadA->AM, LoadA->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
} else {
|
|
|
|
/* ldy #offs */
|
|
const char* Arg = MakeHexArg (LI->A.Offs);
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* opc (sp),y */
|
|
X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
}
|
|
|
|
/* In both cases, we can remove the load */
|
|
LI->A.Flags |= LI_REMOVE;
|
|
|
|
} else {
|
|
|
|
/* Op with temp storage */
|
|
X = NewCodeEntry (OPC, AM65_ZP, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void AddOpHigh (StackOpData* D, opc_t OPC, LoadInfo* LI, int KeepResult)
|
|
/* Add an op for the high byte of an operator. Special cases (constant values
|
|
** or similar) have to be checked separately, the function covers only the
|
|
** generic case. Code is inserted at the insertion point.
|
|
*/
|
|
{
|
|
CodeEntry* X;
|
|
|
|
if (KeepResult) {
|
|
/* pha */
|
|
X = NewCodeEntry (OP65_PHA, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
}
|
|
|
|
/* txa */
|
|
X = NewCodeEntry (OP65_TXA, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
if ((LI->X.Flags & LI_DIRECT) != 0) {
|
|
|
|
if ((LI->X.Flags & LI_RELOAD_Y) == 0) {
|
|
|
|
/* opc xxx */
|
|
CodeEntry* LoadX = LI->X.LoadEntry;
|
|
X = NewCodeEntry (OPC, LoadX->AM, LoadX->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
} else {
|
|
|
|
/* ldy #const */
|
|
const char* Arg = MakeHexArg (LI->X.Offs);
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* opc (sp),y */
|
|
X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
}
|
|
|
|
/* In both cases, we can remove the load */
|
|
LI->X.Flags |= LI_REMOVE;
|
|
|
|
} else {
|
|
/* opc zphi */
|
|
X = NewCodeEntry (OPC, AM65_ZP, D->ZPHi, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
}
|
|
|
|
if (KeepResult) {
|
|
/* tax */
|
|
X = NewCodeEntry (OP65_TAX, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* pla */
|
|
X = NewCodeEntry (OP65_PLA, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void RemoveRegLoads (StackOpData* D, LoadInfo* LI)
|
|
/* Remove register load insns */
|
|
{
|
|
/* Both registers may be loaded with one insn, but DelEntry will in this
|
|
** case clear the other one.
|
|
*/
|
|
if ((LI->A.Flags & (LI_REMOVE | LI_DONT_REMOVE)) == LI_REMOVE) {
|
|
if (LI->A.LoadIndex >= 0) {
|
|
DelEntry (D, LI->A.LoadIndex);
|
|
}
|
|
if (LI->A.XferIndex >= 0) {
|
|
DelEntry (D, LI->A.XferIndex);
|
|
}
|
|
}
|
|
if ((LI->X.Flags & (LI_REMOVE | LI_DONT_REMOVE)) == LI_REMOVE) {
|
|
if (LI->X.LoadIndex >= 0) {
|
|
DelEntry (D, LI->X.LoadIndex);
|
|
}
|
|
if (LI->X.XferIndex >= 0) {
|
|
DelEntry (D, LI->X.XferIndex);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static void RemoveRemainders (StackOpData* D)
|
|
/* Remove the code that is unnecessary after translation of the sequence */
|
|
{
|
|
/* Remove the register loads for lhs and rhs */
|
|
RemoveRegLoads (D, &D->Lhs);
|
|
RemoveRegLoads (D, &D->Rhs);
|
|
|
|
/* Remove the push and the operator routine */
|
|
DelEntry (D, D->OpIndex);
|
|
DelEntry (D, D->PushIndex);
|
|
}
|
|
|
|
|
|
|
|
static int IsRegVar (StackOpData* D)
|
|
/* If the value pushed is that of a zeropage variable, replace ZPLo and ZPHi
|
|
** in the given StackOpData struct by the variable and return true. Otherwise
|
|
** leave D untouched and return false.
|
|
*/
|
|
{
|
|
CodeEntry* LoadA = D->Lhs.A.LoadEntry;
|
|
CodeEntry* LoadX = D->Lhs.X.LoadEntry;
|
|
unsigned Len;
|
|
|
|
/* Must have both load insns */
|
|
if (LoadA == 0 || LoadX == 0) {
|
|
return 0;
|
|
}
|
|
|
|
/* Must be loads from zp */
|
|
if (LoadA->AM != AM65_ZP || LoadX->AM != AM65_ZP) {
|
|
return 0;
|
|
}
|
|
|
|
/* Must be the same zp loc with high byte in X */
|
|
Len = strlen (LoadA->Arg);
|
|
if (strncmp (LoadA->Arg, LoadX->Arg, Len) != 0 ||
|
|
strcmp (LoadX->Arg + Len, "+1") != 0) {
|
|
return 0;
|
|
}
|
|
|
|
/* Use the zero page location directly */
|
|
D->ZPLo = LoadA->Arg;
|
|
D->ZPHi = LoadX->Arg;
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Actual optimization functions */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
static unsigned Opt_toseqax_tosneax (StackOpData* D, const char* BoolTransformer)
|
|
/* Optimize the toseqax and tosneax sequences. */
|
|
{
|
|
CodeEntry* X;
|
|
CodeLabel* L;
|
|
|
|
/* Create a call to the boolean transformer function and a label for this
|
|
** insn. This is needed for all variants. Other insns are inserted *before*
|
|
** the call.
|
|
*/
|
|
X = NewCodeEntry (OP65_JSR, AM65_ABS, BoolTransformer, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex + 1);
|
|
L = CS_GenLabel (D->Code, X);
|
|
|
|
/* If the lhs is direct (but not stack relative), encode compares with lhs
|
|
** effectively reverting the order (which doesn't matter for ==).
|
|
*/
|
|
if ((D->Lhs.A.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT &&
|
|
(D->Lhs.X.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT) {
|
|
|
|
CodeEntry* LoadX = D->Lhs.X.LoadEntry;
|
|
CodeEntry* LoadA = D->Lhs.A.LoadEntry;
|
|
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* cpx */
|
|
X = NewCodeEntry (OP65_CPX, LoadX->AM, LoadX->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* bne L */
|
|
X = NewCodeEntry (OP65_BNE, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* cmp */
|
|
X = NewCodeEntry (OP65_CMP, LoadA->AM, LoadA->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Lhs load entries can be removed */
|
|
D->Lhs.X.Flags |= LI_REMOVE;
|
|
D->Lhs.A.Flags |= LI_REMOVE;
|
|
|
|
} else if ((D->Rhs.A.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT &&
|
|
(D->Rhs.X.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT) {
|
|
|
|
CodeEntry* LoadX = D->Rhs.X.LoadEntry;
|
|
CodeEntry* LoadA = D->Rhs.A.LoadEntry;
|
|
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* cpx */
|
|
X = NewCodeEntry (OP65_CPX, LoadX->AM, LoadX->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* bne L */
|
|
X = NewCodeEntry (OP65_BNE, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* cmp */
|
|
X = NewCodeEntry (OP65_CMP, LoadA->AM, LoadA->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Rhs load entries can be removed */
|
|
D->Rhs.X.Flags |= LI_REMOVE;
|
|
D->Rhs.A.Flags |= LI_REMOVE;
|
|
|
|
} else if ((D->Rhs.A.Flags & LI_DIRECT) != 0 &&
|
|
(D->Rhs.X.Flags & LI_DIRECT) != 0) {
|
|
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Add operand for low byte */
|
|
AddOpLow (D, OP65_CMP, &D->Rhs);
|
|
|
|
/* bne L */
|
|
X = NewCodeEntry (OP65_BNE, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Add operand for high byte */
|
|
AddOpHigh (D, OP65_CMP, &D->Rhs, 0);
|
|
|
|
} else {
|
|
|
|
/* Save lhs into zeropage, then compare */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* cpx */
|
|
X = NewCodeEntry (OP65_CPX, AM65_ZP, D->ZPHi, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* bne L */
|
|
X = NewCodeEntry (OP65_BNE, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* cmp */
|
|
X = NewCodeEntry (OP65_CMP, AM65_ZP, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
}
|
|
|
|
/* Remove the push and the call to the tosgeax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosshift (StackOpData* D, const char* Name)
|
|
/* Optimize shift sequences. */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
ReplacePushByStore (D);
|
|
|
|
/* If the lhs is direct (but not stack relative), we can just reload the
|
|
** data later.
|
|
*/
|
|
if ((D->Lhs.A.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT &&
|
|
(D->Lhs.X.Flags & (LI_DIRECT | LI_RELOAD_Y)) == LI_DIRECT) {
|
|
|
|
CodeEntry* LoadX = D->Lhs.X.LoadEntry;
|
|
CodeEntry* LoadA = D->Lhs.A.LoadEntry;
|
|
|
|
/* Inline the shift */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* tay */
|
|
X = NewCodeEntry (OP65_TAY, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* lda */
|
|
X = NewCodeEntry (OP65_LDA, LoadA->AM, LoadA->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* ldx */
|
|
X = NewCodeEntry (OP65_LDX, LoadX->AM, LoadX->Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Lhs load entries can be removed */
|
|
D->Lhs.X.Flags |= LI_REMOVE;
|
|
D->Lhs.A.Flags |= LI_REMOVE;
|
|
|
|
} else {
|
|
|
|
/* Save lhs into zeropage and reload later */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
|
|
/* Be sure to setup IP after adding the stores, otherwise it will get
|
|
** messed up.
|
|
*/
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* tay */
|
|
X = NewCodeEntry (OP65_TAY, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* lda zp */
|
|
X = NewCodeEntry (OP65_LDA, AM65_ZP, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* ldx zp+1 */
|
|
X = NewCodeEntry (OP65_LDX, AM65_ZP, D->ZPHi, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
}
|
|
|
|
/* jsr shlaxy/aslaxy/whatever */
|
|
X = NewCodeEntry (OP65_JSR, AM65_ABS, Name, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the shift function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt___bzero (StackOpData* D)
|
|
/* Optimize the __bzero sequence */
|
|
{
|
|
CodeEntry* X;
|
|
const char* Arg;
|
|
CodeLabel* L;
|
|
|
|
/* Check if we're using a register variable */
|
|
if (!IsRegVar (D)) {
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
}
|
|
|
|
/* If the return value of __bzero is used, we have to add code to reload
|
|
** a/x from the pointer variable.
|
|
*/
|
|
if (RegAXUsed (D->Code, D->OpIndex+1)) {
|
|
X = NewCodeEntry (OP65_LDA, AM65_ZP, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+1);
|
|
X = NewCodeEntry (OP65_LDX, AM65_ZP, D->ZPHi, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+2);
|
|
}
|
|
|
|
/* X is always zero, A contains the size of the data area to zero.
|
|
** Note: A may be zero, in which case the operation is null op.
|
|
*/
|
|
if (D->OpEntry->RI->In.RegA != 0) {
|
|
|
|
/* lda #$00 */
|
|
X = NewCodeEntry (OP65_LDA, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+1);
|
|
|
|
/* The value of A is known */
|
|
if (D->OpEntry->RI->In.RegA <= 0x81) {
|
|
|
|
/* Loop using the sign bit */
|
|
|
|
/* ldy #count-1 */
|
|
Arg = MakeHexArg (D->OpEntry->RI->In.RegA - 1);
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+2);
|
|
|
|
/* L: sta (zp),y */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+3);
|
|
L = CS_GenLabel (D->Code, X);
|
|
|
|
/* dey */
|
|
X = NewCodeEntry (OP65_DEY, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+4);
|
|
|
|
/* bpl L */
|
|
X = NewCodeEntry (OP65_BPL, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+5);
|
|
|
|
} else {
|
|
|
|
/* Loop using an explicit compare */
|
|
|
|
/* ldy #$00 */
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+2);
|
|
|
|
/* L: sta (zp),y */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+3);
|
|
L = CS_GenLabel (D->Code, X);
|
|
|
|
/* iny */
|
|
X = NewCodeEntry (OP65_INY, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+4);
|
|
|
|
/* cpy #count */
|
|
Arg = MakeHexArg (D->OpEntry->RI->In.RegA);
|
|
X = NewCodeEntry (OP65_CPY, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+5);
|
|
|
|
/* bne L */
|
|
X = NewCodeEntry (OP65_BNE, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+6);
|
|
}
|
|
|
|
}
|
|
|
|
/* Remove the push and the call to the __bzero function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_staspidx (StackOpData* D)
|
|
/* Optimize the staspidx sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
/* Check if we're using a register variable */
|
|
if (!IsRegVar (D)) {
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
}
|
|
|
|
/* Replace the store subroutine call by a direct op */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+1);
|
|
|
|
/* Remove the push and the call to the staspidx function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_staxspidx (StackOpData* D)
|
|
/* Optimize the staxspidx sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
/* Check if we're using a register variable */
|
|
if (!IsRegVar (D)) {
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
}
|
|
|
|
/* Inline the store */
|
|
|
|
/* sta (zp),y */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+1);
|
|
|
|
if (RegValIsKnown (D->OpEntry->RI->In.RegY)) {
|
|
/* Value of Y is known */
|
|
const char* Arg = MakeHexArg (D->OpEntry->RI->In.RegY + 1);
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
} else {
|
|
X = NewCodeEntry (OP65_INY, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
}
|
|
InsertEntry (D, X, D->OpIndex+2);
|
|
|
|
if (RegValIsKnown (D->OpEntry->RI->In.RegX)) {
|
|
/* Value of X is known */
|
|
const char* Arg = MakeHexArg (D->OpEntry->RI->In.RegX);
|
|
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
} else {
|
|
/* Value unknown */
|
|
X = NewCodeEntry (OP65_TXA, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
}
|
|
InsertEntry (D, X, D->OpIndex+3);
|
|
|
|
/* sta (zp),y */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, D->ZPLo, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+4);
|
|
|
|
/* If we remove staxspidx, we must restore the Y register to what the
|
|
** function would return.
|
|
*/
|
|
X = NewCodeEntry (OP65_LDY, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->OpIndex+5);
|
|
|
|
/* Remove the push and the call to the staxspidx function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosaddax (StackOpData* D)
|
|
/* Optimize the tosaddax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
CodeEntry* N;
|
|
|
|
/* We need the entry behind the add */
|
|
CHECK (D->NextEntry != 0);
|
|
|
|
/* Check if the X register is known and zero when the add is done, and
|
|
** if the add is followed by
|
|
**
|
|
** ldy #$00
|
|
** jsr ldauidx ; or ldaidx
|
|
**
|
|
** If this is true, the addition does actually add an offset to a pointer
|
|
** before it is dereferenced. Since both subroutines take an offset in Y,
|
|
** we can pass the offset (instead of #$00) and remove the addition
|
|
** alltogether.
|
|
*/
|
|
if (D->OpEntry->RI->In.RegX == 0 &&
|
|
D->NextEntry->OPC == OP65_LDY &&
|
|
CE_IsKnownImm (D->NextEntry, 0) &&
|
|
!CE_HasLabel (D->NextEntry) &&
|
|
(N = CS_GetNextEntry (D->Code, D->OpIndex + 1)) != 0 &&
|
|
(CE_IsCallTo (N, "ldauidx") ||
|
|
CE_IsCallTo (N, "ldaidx"))) {
|
|
|
|
int Signed = (strcmp (N->Arg, "ldaidx") == 0);
|
|
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
AddStoreX (D);
|
|
AddStoreA (D);
|
|
|
|
/* Replace the ldy by a tay. Be sure to create the new entry before
|
|
** deleting the ldy, since we will reference the line info from this
|
|
** insn.
|
|
*/
|
|
X = NewCodeEntry (OP65_TAY, AM65_IMP, 0, 0, D->NextEntry->LI);
|
|
DelEntry (D, D->OpIndex + 1);
|
|
InsertEntry (D, X, D->OpIndex + 1);
|
|
|
|
/* Replace the call to ldaidx/ldauidx. Since X is already zero, and
|
|
** the ptr is in the zero page location, we just need to load from
|
|
** the pointer, and fix X in case of ldaidx.
|
|
*/
|
|
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, D->ZPLo, 0, N->LI);
|
|
DelEntry (D, D->OpIndex + 2);
|
|
InsertEntry (D, X, D->OpIndex + 2);
|
|
if (Signed) {
|
|
|
|
CodeLabel* L;
|
|
|
|
/* Add sign extension - N is unused now */
|
|
N = CS_GetNextEntry (D->Code, D->OpIndex + 2);
|
|
CHECK (N != 0);
|
|
L = CS_GenLabel (D->Code, N);
|
|
|
|
X = NewCodeEntry (OP65_BPL, AM65_BRA, L->Name, L, X->LI);
|
|
InsertEntry (D, X, D->OpIndex + 3);
|
|
|
|
X = NewCodeEntry (OP65_DEX, AM65_IMP, 0, 0, X->LI);
|
|
InsertEntry (D, X, D->OpIndex + 4);
|
|
}
|
|
|
|
} else {
|
|
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
ReplacePushByStore (D);
|
|
|
|
/* Inline the add */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* clc */
|
|
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Low byte */
|
|
AddOpLow (D, OP65_ADC, &D->Lhs);
|
|
|
|
/* High byte */
|
|
if (D->PushEntry->RI->In.RegX == 0) {
|
|
|
|
/* The high byte is the value in X plus the carry */
|
|
CodeLabel* L = CS_GenLabel (D->Code, D->NextEntry);
|
|
|
|
/* bcc L */
|
|
X = NewCodeEntry (OP65_BCC, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* inx */
|
|
X = NewCodeEntry (OP65_INX, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
} else if (D->OpEntry->RI->In.RegX == 0 &&
|
|
(RegValIsKnown (D->PushEntry->RI->In.RegX) ||
|
|
(D->Lhs.X.Flags & LI_RELOAD_Y) == 0)) {
|
|
|
|
/* The high byte is that of the first operand plus carry */
|
|
CodeLabel* L;
|
|
if (RegValIsKnown (D->PushEntry->RI->In.RegX)) {
|
|
/* Value of first op high byte is known */
|
|
const char* Arg = MakeHexArg (D->PushEntry->RI->In.RegX);
|
|
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
} else {
|
|
/* Value of first op high byte is unknown. Load from ZP or
|
|
** original storage.
|
|
*/
|
|
if (D->Lhs.X.Flags & LI_DIRECT) {
|
|
CodeEntry* LoadX = D->Lhs.X.LoadEntry;
|
|
X = NewCodeEntry (OP65_LDX, LoadX->AM, LoadX->Arg, 0, D->OpEntry->LI);
|
|
} else {
|
|
X = NewCodeEntry (OP65_LDX, AM65_ZP, D->ZPHi, 0, D->OpEntry->LI);
|
|
}
|
|
}
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* bcc label */
|
|
L = CS_GenLabel (D->Code, D->NextEntry);
|
|
X = NewCodeEntry (OP65_BCC, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* inx */
|
|
X = NewCodeEntry (OP65_INX, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
} else {
|
|
/* High byte is unknown */
|
|
AddOpHigh (D, OP65_ADC, &D->Lhs, 1);
|
|
}
|
|
}
|
|
|
|
/* Remove the push and the call to the tosaddax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosandax (StackOpData* D)
|
|
/* Optimize the tosandax sequence */
|
|
{
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
ReplacePushByStore (D);
|
|
|
|
/* Inline the and, low byte */
|
|
D->IP = D->OpIndex + 1;
|
|
AddOpLow (D, OP65_AND, &D->Lhs);
|
|
|
|
/* High byte */
|
|
AddOpHigh (D, OP65_AND, &D->Lhs, 1);
|
|
|
|
/* Remove the push and the call to the tosandax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosaslax (StackOpData* D)
|
|
/* Optimize the tosaslax sequence */
|
|
{
|
|
return Opt_tosshift (D, "aslaxy");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosasrax (StackOpData* D)
|
|
/* Optimize the tosasrax sequence */
|
|
{
|
|
return Opt_tosshift (D, "asraxy");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_toseqax (StackOpData* D)
|
|
/* Optimize the toseqax sequence */
|
|
{
|
|
return Opt_toseqax_tosneax (D, "booleq");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosgeax (StackOpData* D)
|
|
/* Optimize the tosgeax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
CodeLabel* L;
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_CMP, &D->Rhs);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* eor #$80 */
|
|
X = NewCodeEntry (OP65_EOR, AM65_IMM, "$80", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* asl a */
|
|
X = NewCodeEntry (OP65_ASL, AM65_ACC, "a", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
L = CS_GenLabel (D->Code, X);
|
|
|
|
/* Insert a bvs L before the eor insn */
|
|
X = NewCodeEntry (OP65_BVS, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP - 2);
|
|
++D->IP;
|
|
|
|
/* lda #$00 */
|
|
X = NewCodeEntry (OP65_LDA, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* ldx #$00 */
|
|
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* rol a */
|
|
X = NewCodeEntry (OP65_ROL, AM65_ACC, "a", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the tosgeax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosltax (StackOpData* D)
|
|
/* Optimize the tosltax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
CodeLabel* L;
|
|
|
|
|
|
/* Inline the compare */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_CMP, &D->Rhs);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* eor #$80 */
|
|
X = NewCodeEntry (OP65_EOR, AM65_IMM, "$80", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* asl a */
|
|
X = NewCodeEntry (OP65_ASL, AM65_ACC, "a", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
L = CS_GenLabel (D->Code, X);
|
|
|
|
/* Insert a bvc L before the eor insn */
|
|
X = NewCodeEntry (OP65_BVC, AM65_BRA, L->Name, L, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP - 2);
|
|
++D->IP;
|
|
|
|
/* lda #$00 */
|
|
X = NewCodeEntry (OP65_LDA, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* ldx #$00 */
|
|
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* rol a */
|
|
X = NewCodeEntry (OP65_ROL, AM65_ACC, "a", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the tosltax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosneax (StackOpData* D)
|
|
/* Optimize the tosneax sequence */
|
|
{
|
|
return Opt_toseqax_tosneax (D, "boolne");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosorax (StackOpData* D)
|
|
/* Optimize the tosorax sequence */
|
|
{
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
ReplacePushByStore (D);
|
|
|
|
/* Inline the or, low byte */
|
|
D->IP = D->OpIndex + 1;
|
|
AddOpLow (D, OP65_ORA, &D->Lhs);
|
|
|
|
/* High byte */
|
|
AddOpHigh (D, OP65_ORA, &D->Lhs, 1);
|
|
|
|
/* Remove the push and the call to the tosorax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosshlax (StackOpData* D)
|
|
/* Optimize the tosshlax sequence */
|
|
{
|
|
return Opt_tosshift (D, "shlaxy");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosshrax (StackOpData* D)
|
|
/* Optimize the tosshrax sequence */
|
|
{
|
|
return Opt_tosshift (D, "shraxy");
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tossubax (StackOpData* D)
|
|
/* Optimize the tossubax sequence. Note: subtraction is not commutative! */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* sec */
|
|
X = NewCodeEntry (OP65_SEC, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_SBC, &D->Rhs);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 1);
|
|
|
|
/* Remove the push and the call to the tossubax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosugeax (StackOpData* D)
|
|
/* Optimize the tosugeax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_CMP, &D->Rhs);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* lda #$00 */
|
|
X = NewCodeEntry (OP65_LDA, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* ldx #$00 */
|
|
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* rol a */
|
|
X = NewCodeEntry (OP65_ROL, AM65_ACC, "a", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the tosugeax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosugtax (StackOpData* D)
|
|
/* Optimize the tosugtax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* sec */
|
|
X = NewCodeEntry (OP65_SEC, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_SBC, &D->Rhs);
|
|
|
|
/* We need the zero flag, so remember the immediate result */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP, "tmp1", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* Set Z flag */
|
|
X = NewCodeEntry (OP65_ORA, AM65_ZP, "tmp1", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Transform to boolean */
|
|
X = NewCodeEntry (OP65_JSR, AM65_ABS, "boolugt", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the operator function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosuleax (StackOpData* D)
|
|
/* Optimize the tosuleax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* sec */
|
|
X = NewCodeEntry (OP65_SEC, AM65_IMP, 0, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_SBC, &D->Rhs);
|
|
|
|
/* We need the zero flag, so remember the immediate result */
|
|
X = NewCodeEntry (OP65_STA, AM65_ZP, "tmp1", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* Set Z flag */
|
|
X = NewCodeEntry (OP65_ORA, AM65_ZP, "tmp1", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Transform to boolean */
|
|
X = NewCodeEntry (OP65_JSR, AM65_ABS, "boolule", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the operator function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosultax (StackOpData* D)
|
|
/* Optimize the tosultax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Inline the sbc */
|
|
D->IP = D->OpIndex+1;
|
|
|
|
/* Must be true because of OP_RHS_LOAD */
|
|
CHECK ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) != 0);
|
|
|
|
/* Add code for low operand */
|
|
AddOpLow (D, OP65_CMP, &D->Rhs);
|
|
|
|
/* Add code for high operand */
|
|
AddOpHigh (D, OP65_SBC, &D->Rhs, 0);
|
|
|
|
/* Transform to boolean */
|
|
X = NewCodeEntry (OP65_JSR, AM65_ABS, "boolult", 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
|
|
/* Remove the push and the call to the operator function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static unsigned Opt_tosxorax (StackOpData* D)
|
|
/* Optimize the tosxorax sequence */
|
|
{
|
|
CodeEntry* X;
|
|
|
|
|
|
/* Store the value into the zeropage instead of pushing it */
|
|
ReplacePushByStore (D);
|
|
|
|
/* Inline the xor, low byte */
|
|
D->IP = D->OpIndex + 1;
|
|
AddOpLow (D, OP65_EOR, &D->Lhs);
|
|
|
|
/* High byte */
|
|
if (RegValIsKnown (D->PushEntry->RI->In.RegX) &&
|
|
RegValIsKnown (D->OpEntry->RI->In.RegX)) {
|
|
/* Both values known, precalculate the result */
|
|
const char* Arg = MakeHexArg (D->PushEntry->RI->In.RegX ^ D->OpEntry->RI->In.RegX);
|
|
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, D->OpEntry->LI);
|
|
InsertEntry (D, X, D->IP++);
|
|
} else if (D->PushEntry->RI->In.RegX != 0) {
|
|
/* High byte is unknown */
|
|
AddOpHigh (D, OP65_EOR, &D->Lhs, 1);
|
|
}
|
|
|
|
/* Remove the push and the call to the tosandax function */
|
|
RemoveRemainders (D);
|
|
|
|
/* We changed the sequence */
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Code */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
static const OptFuncDesc FuncTable[] = {
|
|
{ "__bzero", Opt___bzero, REG_NONE, OP_X_ZERO | OP_A_KNOWN },
|
|
{ "staspidx", Opt_staspidx, REG_NONE, OP_NONE },
|
|
{ "staxspidx", Opt_staxspidx, REG_AX, OP_NONE },
|
|
{ "tosaddax", Opt_tosaddax, REG_NONE, OP_NONE },
|
|
{ "tosandax", Opt_tosandax, REG_NONE, OP_NONE },
|
|
{ "tosaslax", Opt_tosaslax, REG_NONE, OP_NONE },
|
|
{ "tosasrax", Opt_tosasrax, REG_NONE, OP_NONE },
|
|
{ "toseqax", Opt_toseqax, REG_NONE, OP_NONE },
|
|
{ "tosgeax", Opt_tosgeax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosltax", Opt_tosltax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosneax", Opt_tosneax, REG_NONE, OP_NONE },
|
|
{ "tosorax", Opt_tosorax, REG_NONE, OP_NONE },
|
|
{ "tosshlax", Opt_tosshlax, REG_NONE, OP_NONE },
|
|
{ "tosshrax", Opt_tosshrax, REG_NONE, OP_NONE },
|
|
{ "tossubax", Opt_tossubax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosugeax", Opt_tosugeax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosugtax", Opt_tosugtax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosuleax", Opt_tosuleax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosultax", Opt_tosultax, REG_NONE, OP_RHS_LOAD_DIRECT },
|
|
{ "tosxorax", Opt_tosxorax, REG_NONE, OP_NONE },
|
|
};
|
|
#define FUNC_COUNT (sizeof(FuncTable) / sizeof(FuncTable[0]))
|
|
|
|
|
|
|
|
static int CmpFunc (const void* Key, const void* Func)
|
|
/* Compare function for bsearch */
|
|
{
|
|
return strcmp (Key, ((const OptFuncDesc*) Func)->Name);
|
|
}
|
|
|
|
|
|
|
|
static const OptFuncDesc* FindFunc (const char* Name)
|
|
/* Find the function with the given name. Return a pointer to the table entry
|
|
** or NULL if the function was not found.
|
|
*/
|
|
{
|
|
return bsearch (Name, FuncTable, FUNC_COUNT, sizeof(OptFuncDesc), CmpFunc);
|
|
}
|
|
|
|
|
|
|
|
static int CmpHarmless (const void* Key, const void* Entry)
|
|
/* Compare function for bsearch */
|
|
{
|
|
return strcmp (Key, *(const char**)Entry);
|
|
}
|
|
|
|
|
|
|
|
static int HarmlessCall (const char* Name)
|
|
/* Check if this is a call to a harmless subroutine that will not interrupt
|
|
** the pushax/op sequence when encountered.
|
|
*/
|
|
{
|
|
static const char* const Tab[] = {
|
|
"aslax1",
|
|
"aslax2",
|
|
"aslax3",
|
|
"aslax4",
|
|
"aslaxy",
|
|
"asrax1",
|
|
"asrax2",
|
|
"asrax3",
|
|
"asrax4",
|
|
"asraxy",
|
|
"bnegax",
|
|
"complax",
|
|
"decax1",
|
|
"decax2",
|
|
"decax3",
|
|
"decax4",
|
|
"decax5",
|
|
"decax6",
|
|
"decax7",
|
|
"decax8",
|
|
"decaxy",
|
|
"incax1",
|
|
"incax2",
|
|
"incax3",
|
|
"incax4",
|
|
"incax5",
|
|
"incax6",
|
|
"incax7",
|
|
"incax8",
|
|
"incaxy",
|
|
"ldaxidx",
|
|
"ldaxysp",
|
|
"negax",
|
|
"shlax1",
|
|
"shlax2",
|
|
"shlax3",
|
|
"shlax4",
|
|
"shlaxy",
|
|
"shrax1",
|
|
"shrax2",
|
|
"shrax3",
|
|
"shrax4",
|
|
"shraxy",
|
|
};
|
|
|
|
void* R = bsearch (Name,
|
|
Tab,
|
|
sizeof (Tab) / sizeof (Tab[0]),
|
|
sizeof (Tab[0]),
|
|
CmpHarmless);
|
|
return (R != 0);
|
|
}
|
|
|
|
|
|
|
|
static void ResetStackOpData (StackOpData* Data)
|
|
/* Reset the given data structure */
|
|
{
|
|
Data->OptFunc = 0;
|
|
Data->UsedRegs = REG_NONE;
|
|
|
|
ClearLoadInfo (&Data->Lhs);
|
|
ClearLoadInfo (&Data->Rhs);
|
|
|
|
Data->PushIndex = -1;
|
|
Data->OpIndex = -1;
|
|
}
|
|
|
|
|
|
|
|
static int PreCondOk (StackOpData* D)
|
|
/* Check if the preconditions for a call to the optimizer subfunction are
|
|
** satisfied. As a side effect, this function will also choose the zero page
|
|
** register to use.
|
|
*/
|
|
{
|
|
/* Check the flags */
|
|
unsigned UnusedRegs = D->OptFunc->UnusedRegs;
|
|
if (UnusedRegs != REG_NONE &&
|
|
(GetRegInfo (D->Code, D->OpIndex+1, UnusedRegs) & UnusedRegs) != 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
if ((D->OptFunc->Flags & OP_A_KNOWN) != 0 &&
|
|
RegValIsUnknown (D->OpEntry->RI->In.RegA)) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
if ((D->OptFunc->Flags & OP_X_ZERO) != 0 &&
|
|
D->OpEntry->RI->In.RegX != 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
if ((D->OptFunc->Flags & OP_LHS_LOAD) != 0) {
|
|
if (D->Lhs.A.LoadIndex < 0 || D->Lhs.X.LoadIndex < 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
} else if ((D->OptFunc->Flags & OP_LHS_LOAD_DIRECT) != 0) {
|
|
if ((D->Lhs.A.Flags & D->Lhs.X.Flags & LI_DIRECT) == 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
if ((D->OptFunc->Flags & OP_RHS_LOAD) != 0) {
|
|
if (D->Rhs.A.LoadIndex < 0 || D->Rhs.X.LoadIndex < 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
} else if ((D->OptFunc->Flags & OP_RHS_LOAD_DIRECT) != 0) {
|
|
if ((D->Rhs.A.Flags & D->Rhs.X.Flags & LI_DIRECT) == 0) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
if ((D->Rhs.A.Flags | D->Rhs.X.Flags) & LI_DUP_LOAD) {
|
|
/* Cannot optimize */
|
|
return 0;
|
|
}
|
|
|
|
/* Determine the zero page locations to use */
|
|
if ((D->UsedRegs & REG_PTR1) == REG_NONE) {
|
|
D->ZPLo = "ptr1";
|
|
D->ZPHi = "ptr1+1";
|
|
} else if ((D->UsedRegs & REG_SREG) == REG_NONE) {
|
|
D->ZPLo = "sreg";
|
|
D->ZPHi = "sreg+1";
|
|
} else if ((D->UsedRegs & REG_PTR2) == REG_NONE) {
|
|
D->ZPLo = "ptr2";
|
|
D->ZPHi = "ptr2+1";
|
|
} else {
|
|
/* No registers available */
|
|
return 0;
|
|
}
|
|
|
|
/* Determine if we have a basic block */
|
|
return CS_IsBasicBlock (D->Code, D->PushIndex, D->OpIndex);
|
|
}
|
|
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* Code */
|
|
/*****************************************************************************/
|
|
|
|
|
|
|
|
unsigned OptStackOps (CodeSeg* S)
|
|
/* Optimize operations that take operands via the stack */
|
|
{
|
|
unsigned Changes = 0; /* Number of changes in one run */
|
|
StackOpData Data;
|
|
int I;
|
|
int OldEntryCount; /* Old number of entries */
|
|
unsigned UsedRegs = 0; /* Registers used */
|
|
unsigned ChangedRegs = 0;/* Registers changed */
|
|
|
|
|
|
enum {
|
|
Initialize,
|
|
Search,
|
|
FoundPush,
|
|
FoundOp
|
|
} State = Initialize;
|
|
|
|
|
|
/* Remember the code segment in the info struct */
|
|
Data.Code = S;
|
|
|
|
/* Look for a call to pushax followed by a call to some other function
|
|
** that takes it's first argument on the stack, and the second argument
|
|
** in the primary register.
|
|
** It depends on the code between the two if we can handle/transform the
|
|
** sequence, so check this code for the following list of things:
|
|
**
|
|
** - the range must be a basic block (one entry, one exit)
|
|
** - there may not be accesses to local variables with unknown
|
|
** offsets (because we have to adjust these offsets).
|
|
** - no subroutine calls
|
|
** - no jump labels
|
|
**
|
|
** Since we need a zero page register later, do also check the
|
|
** intermediate code for zero page use.
|
|
*/
|
|
I = 0;
|
|
while (I < (int)CS_GetEntryCount (S)) {
|
|
|
|
/* Get the next entry */
|
|
CodeEntry* E = CS_GetEntry (S, I);
|
|
|
|
/* Actions depend on state */
|
|
switch (State) {
|
|
|
|
case Initialize:
|
|
ResetStackOpData (&Data);
|
|
UsedRegs = ChangedRegs = REG_NONE;
|
|
State = Search;
|
|
/* FALLTHROUGH */
|
|
|
|
case Search:
|
|
/* While searching, track register load insns, so we can tell
|
|
** what is in a register once pushax is encountered.
|
|
*/
|
|
if (CE_HasLabel (E)) {
|
|
/* Currently we don't track across branches */
|
|
ClearLoadInfo (&Data.Lhs);
|
|
}
|
|
if (CE_IsCallTo (E, "pushax")) {
|
|
Data.PushIndex = I;
|
|
State = FoundPush;
|
|
} else {
|
|
/* Track load insns */
|
|
TrackLoads (&Data.Lhs, E, I);
|
|
}
|
|
break;
|
|
|
|
case FoundPush:
|
|
/* We' found a pushax before. Search for a stack op that may
|
|
** follow and in the meantime, track zeropage usage and check
|
|
** for code that will disable us from translating the sequence.
|
|
*/
|
|
if (CE_HasLabel (E)) {
|
|
/* Currently we don't track across branches */
|
|
ClearLoadInfo (&Data.Rhs);
|
|
}
|
|
if (E->OPC == OP65_JSR) {
|
|
|
|
/* Subroutine call: Check if this is one of the functions,
|
|
** we're going to replace.
|
|
*/
|
|
Data.OptFunc = FindFunc (E->Arg);
|
|
if (Data.OptFunc) {
|
|
/* Remember the op index and go on */
|
|
Data.OpIndex = I;
|
|
Data.OpEntry = E;
|
|
State = FoundOp;
|
|
break;
|
|
} else if (!HarmlessCall (E->Arg)) {
|
|
/* A call to an unkown subroutine: We need to start
|
|
** over after the last pushax. Note: This will also
|
|
** happen if we encounter a call to pushax!
|
|
*/
|
|
I = Data.PushIndex;
|
|
State = Initialize;
|
|
break;
|
|
} else {
|
|
/* Track register usage */
|
|
Data.UsedRegs |= (E->Use | E->Chg);
|
|
TrackLoads (&Data.Rhs, E, I);
|
|
}
|
|
|
|
} else if (E->Info & OF_STORE && (E->Chg & REG_ZP) == 0) {
|
|
|
|
/* Too dangerous - there may be a change of a variable
|
|
** within the sequence.
|
|
*/
|
|
I = Data.PushIndex;
|
|
State = Initialize;
|
|
break;
|
|
|
|
} else if ((E->Use & REG_SP) != 0 &&
|
|
(E->AM != AM65_ZP_INDY ||
|
|
RegValIsUnknown (E->RI->In.RegY) ||
|
|
E->RI->In.RegY < 2)) {
|
|
|
|
/* If we are using the stack, and we don't have "indirect Y"
|
|
** addressing mode, or the value of Y is unknown, or less
|
|
** than two, we cannot cope with this piece of code. Having
|
|
** an unknown value of Y means that we cannot correct the
|
|
** stack offset, while having an offset less than two means
|
|
** that the code works with the value on stack which is to
|
|
** be removed.
|
|
*/
|
|
I = Data.PushIndex;
|
|
State = Initialize;
|
|
break;
|
|
|
|
} else {
|
|
/* Other stuff: Track register usage */
|
|
Data.UsedRegs |= (E->Use | E->Chg);
|
|
TrackLoads (&Data.Rhs, E, I);
|
|
}
|
|
/* If the registers from the push (A/X) are used before they're
|
|
** changed, we cannot change the sequence, because this would
|
|
** with a high probability change the register contents.
|
|
*/
|
|
UsedRegs |= E->Use;
|
|
if ((UsedRegs & ~ChangedRegs) & REG_AX) {
|
|
I = Data.PushIndex;
|
|
State = Initialize;
|
|
break;
|
|
}
|
|
ChangedRegs |= E->Chg;
|
|
break;
|
|
|
|
case FoundOp:
|
|
/* Track zero page location usage beyond this point */
|
|
Data.UsedRegs |= GetRegInfo (S, I, REG_SREG | REG_PTR1 | REG_PTR2);
|
|
|
|
/* Finalize the load info */
|
|
FinalizeLoadInfo (&Data.Lhs, S);
|
|
FinalizeLoadInfo (&Data.Rhs, S);
|
|
|
|
/* If the Lhs loads do load from zeropage, we have to include
|
|
** them into UsedRegs registers used. The Rhs loads have already
|
|
** been tracked.
|
|
*/
|
|
if (Data.Lhs.A.LoadEntry && Data.Lhs.A.LoadEntry->AM == AM65_ZP) {
|
|
Data.UsedRegs |= Data.Lhs.A.LoadEntry->Use;
|
|
}
|
|
if (Data.Lhs.X.LoadEntry && Data.Lhs.X.LoadEntry->AM == AM65_ZP) {
|
|
Data.UsedRegs |= Data.Lhs.X.LoadEntry->Use;
|
|
}
|
|
|
|
/* Check the preconditions. If they aren't ok, reset the insn
|
|
** pointer to the pushax and start over. We will loose part of
|
|
** load tracking but at least a/x has probably lost between
|
|
** pushax and here and will be tracked again when restarting.
|
|
*/
|
|
if (!PreCondOk (&Data)) {
|
|
I = Data.PushIndex;
|
|
State = Initialize;
|
|
break;
|
|
}
|
|
|
|
/* Prepare the remainder of the data structure. */
|
|
Data.PrevEntry = CS_GetPrevEntry (S, Data.PushIndex);
|
|
Data.PushEntry = CS_GetEntry (S, Data.PushIndex);
|
|
Data.OpEntry = CS_GetEntry (S, Data.OpIndex);
|
|
Data.NextEntry = CS_GetNextEntry (S, Data.OpIndex);
|
|
|
|
/* Remember the current number of code lines */
|
|
OldEntryCount = CS_GetEntryCount (S);
|
|
|
|
/* Adjust stack offsets to account for the upcoming removal */
|
|
AdjustStackOffset (&Data, 2);
|
|
|
|
/* Regenerate register info, since AdjustStackOffset changed
|
|
** the code
|
|
*/
|
|
CS_GenRegInfo (S);
|
|
|
|
/* Call the optimizer function */
|
|
Changes += Data.OptFunc->Func (&Data);
|
|
|
|
/* Since the function may have added or deleted entries,
|
|
** correct the index.
|
|
*/
|
|
I += CS_GetEntryCount (S) - OldEntryCount;
|
|
|
|
/* Regenerate register info */
|
|
CS_GenRegInfo (S);
|
|
|
|
/* Done */
|
|
State = Initialize;
|
|
continue;
|
|
|
|
}
|
|
|
|
/* Next entry */
|
|
++I;
|
|
|
|
}
|
|
|
|
/* Return the number of changes made */
|
|
return Changes;
|
|
}
|