X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=src%2Fcc65%2Fcoptsub.c;h=fdb1676841170b1c53742091cc5df320107dd5fc;hb=1bcd4b44f84d322871ac774dff831d6524733f21;hp=3b236b678b2b76ed03a37945bd794c8ee0c861c0;hpb=21111ba235f184c962985fd79c4782eaa5990c83;p=cc65 diff --git a/src/cc65/coptsub.c b/src/cc65/coptsub.c index 3b236b678..fdb167684 100644 --- a/src/cc65/coptsub.c +++ b/src/cc65/coptsub.c @@ -1,15 +1,15 @@ /*****************************************************************************/ /* */ -/* coptsub.c */ +/* coptsub.c */ /* */ -/* Optimize subtraction sequences */ +/* Optimize subtraction sequences */ /* */ /* */ /* */ -/* (C) 2001 Ullrich von Bassewitz */ -/* Wacholderweg 14 */ -/* D-70597 Stuttgart */ -/* EMail: uz@cc65.org */ +/* (C) 2001-2006, Ullrich von Bassewitz */ +/* Römerstrasse 52 */ +/* D-70794 Filderstadt */ +/* EMail: uz@cc65.org */ /* */ /* */ /* This software is provided 'as-is', without any expressed or implied */ @@ -33,7 +33,8 @@ -#include +/* common */ +#include "chartype.h" /* cc65 */ #include "codeent.h" @@ -43,7 +44,7 @@ /*****************************************************************************/ -/* Optimize subtractions */ +/* Optimize subtractions */ /*****************************************************************************/ @@ -51,9 +52,9 @@ unsigned OptSub1 (CodeSeg* S) /* Search for the sequence * - * sbc ... + * sbc ... * bcs L - * dex + * dex * L: * * and remove the handling of the high byte if X is not used later. @@ -65,32 +66,32 @@ unsigned OptSub1 (CodeSeg* S) unsigned I = 0; while (I < CS_GetEntryCount (S)) { - CodeEntry* L[3]; + CodeEntry* L[3]; - /* Get next entry */ - CodeEntry* E = CS_GetEntry (S, I); + /* Get next entry */ + CodeEntry* E = CS_GetEntry (S, I); - /* Check for the sequence */ - if (E->OPC == OP65_SBC && - CS_GetEntries (S, L, I+1, 3) && - (L[0]->OPC == OP65_BCS || L[0]->OPC == OP65_JCS) && - L[0]->JumpTo != 0 && - !CE_HasLabel (L[0]) && - L[1]->OPC == OP65_DEX && - !CE_HasLabel (L[1]) && - L[0]->JumpTo->Owner == L[2] && - !RegXUsed (S, I+3)) { + /* Check for the sequence */ + if (E->OPC == OP65_SBC && + CS_GetEntries (S, L, I+1, 3) && + (L[0]->OPC == OP65_BCS || L[0]->OPC == OP65_JCS) && + L[0]->JumpTo != 0 && + !CE_HasLabel (L[0]) && + L[1]->OPC == OP65_DEX && + !CE_HasLabel (L[1]) && + L[0]->JumpTo->Owner == L[2] && + !RegXUsed (S, I+3)) { - /* Remove the bcs/dex */ - CS_DelEntries (S, I+1, 2); + /* Remove the bcs/dex */ + CS_DelEntries (S, I+1, 2); - /* Remember, we had changes */ - ++Changes; + /* Remember, we had changes */ + ++Changes; - } + } - /* Next entry */ - ++I; + /* Next entry */ + ++I; } @@ -103,9 +104,9 @@ unsigned OptSub1 (CodeSeg* S) unsigned OptSub2 (CodeSeg* S) /* Search for the sequence * - * lda xx + * lda xx * sec - * sta tmp1 + * sta tmp1 * lda yy * sbc tmp1 * sta yy @@ -114,7 +115,7 @@ unsigned OptSub2 (CodeSeg* S) * * sec * lda yy - * sbc xx + * sbc xx * sta yy */ { @@ -124,54 +125,50 @@ unsigned OptSub2 (CodeSeg* S) unsigned I = 0; while (I < CS_GetEntryCount (S)) { - CodeEntry* L[5]; - - /* Get next entry */ - CodeEntry* E = CS_GetEntry (S, I); - - /* Check for the sequence */ - if (E->OPC == OP65_LDA && - CS_GetEntries (S, L, I+1, 5) && - L[0]->OPC == OP65_SEC && - !CE_HasLabel (L[0]) && - L[1]->OPC == OP65_STA && - strcmp (L[1]->Arg, "tmp1") == 0 && - !CE_HasLabel (L[1]) && - L[2]->OPC == OP65_LDA && - !CE_HasLabel (L[2]) && - L[3]->OPC == OP65_SBC && - strcmp (L[3]->Arg, "tmp1") == 0 && - !CE_HasLabel (L[3]) && - L[4]->OPC == OP65_STA && - strcmp (L[4]->Arg, L[2]->Arg) == 0 && - !CE_HasLabel (L[4])) { - - /* Remove the store to tmp1 */ - CS_DelEntry (S, I+2); - - /* Remove the subtraction */ - CS_DelEntry (S, I+3); - - /* Move the lda to the position of the subtraction and change the - * op to SBC. - */ - CS_MoveEntry (S, I, I+3); - CE_ReplaceOPC (E, OP65_SBC); - - /* If the sequence head had a label, move this label back to the - * head. - */ - if (CE_HasLabel (E)) { - CS_MoveLabels (S, E, L[0]); - } - - /* Remember, we had changes */ - ++Changes; - - } - - /* Next entry */ - ++I; + CodeEntry* L[5]; + + /* Get next entry */ + CodeEntry* E = CS_GetEntry (S, I); + + /* Check for the sequence */ + if (E->OPC == OP65_LDA && + !CS_RangeHasLabel (S, I+1, 5) && + CS_GetEntries (S, L, I+1, 5) && + L[0]->OPC == OP65_SEC && + L[1]->OPC == OP65_STA && + strcmp (L[1]->Arg, "tmp1") == 0 && + L[2]->OPC == OP65_LDA && + L[3]->OPC == OP65_SBC && + strcmp (L[3]->Arg, "tmp1") == 0 && + L[4]->OPC == OP65_STA && + strcmp (L[4]->Arg, L[2]->Arg) == 0) { + + /* Remove the store to tmp1 */ + CS_DelEntry (S, I+2); + + /* Remove the subtraction */ + CS_DelEntry (S, I+3); + + /* Move the lda to the position of the subtraction and change the + * op to SBC. + */ + CS_MoveEntry (S, I, I+3); + CE_ReplaceOPC (E, OP65_SBC); + + /* If the sequence head had a label, move this label back to the + * head. + */ + if (CE_HasLabel (E)) { + CS_MoveLabels (S, E, L[0]); + } + + /* Remember, we had changes */ + ++Changes; + + } + + /* Next entry */ + ++I; } @@ -181,4 +178,56 @@ unsigned OptSub2 (CodeSeg* S) +unsigned OptSub3 (CodeSeg* S) +/* Search for a call to decaxn and replace it by an 8 bit sub if the X register + * is not used later. + */ +{ + unsigned Changes = 0; + + /* Walk over the entries */ + unsigned I = 0; + while (I < CS_GetEntryCount (S)) { + + CodeEntry* E; + + /* Get next entry */ + E = CS_GetEntry (S, I); + + /* Check for the sequence */ + if (E->OPC == OP65_JSR && + strncmp (E->Arg, "decax", 5) == 0 && + IsDigit (E->Arg[5]) && + E->Arg[6] == '\0' && + !RegXUsed (S, I+1)) { + + CodeEntry* X; + const char* Arg; + + /* Insert new code behind the sequence */ + X = NewCodeEntry (OP65_SEC, AM65_IMP, 0, 0, E->LI); + CS_InsertEntry (S, X, I+1); + + Arg = MakeHexArg (E->Arg[5] - '0'); + X = NewCodeEntry (OP65_SBC, AM65_IMM, Arg, 0, E->LI); + CS_InsertEntry (S, X, I+2); + + /* Delete the old code */ + CS_DelEntry (S, I); + + /* Remember, we had changes */ + ++Changes; + + } + + /* Next entry */ + ++I; + + } + + /* Return the number of changes made */ + return Changes; +} + +