X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=src%2Fcc65%2Fcoptcmp.c;h=012291e9acc4da9be9906c60778b883446d90c9e;hb=53518d59c9eb424bce359eecb7170d7f2970b105;hp=dd24c48c4e55667695e9e3f9da4f2ea1954e19ba;hpb=21c6e1badb3dcb0631e12e716dc9e619625b8dcb;p=cc65 diff --git a/src/cc65/coptcmp.c b/src/cc65/coptcmp.c index dd24c48c4..012291e9a 100644 --- a/src/cc65/coptcmp.c +++ b/src/cc65/coptcmp.c @@ -6,7 +6,7 @@ /* */ /* */ /* */ -/* (C) 2001 Ullrich von Bassewitz */ +/* (C) 2001-2002 Ullrich von Bassewitz */ /* Wacholderweg 14 */ /* D-70597 Stuttgart */ /* EMail: uz@cc65.org */ @@ -49,26 +49,6 @@ -/* Defines for the conditions in a compare */ -typedef enum { - CMP_INV = -1, - CMP_EQ, - CMP_NE, - CMP_GT, - CMP_GE, - CMP_LT, - CMP_LE, - CMP_UGT, - CMP_UGE, - CMP_ULT, - CMP_ULE -} cmp_t; - -/* Table with the compare suffixes */ -static const char CmpSuffixTab [][4] = { - "eq", "ne", "gt", "ge", "lt", "le", "ugt", "uge", "ult", "ule" -}; - /* Table used to invert a condition, indexed by condition */ static const unsigned char CmpInvertTab [] = { CMP_NE, CMP_EQ, @@ -89,59 +69,6 @@ static const char CmpSignedTab [] = { -static cmp_t FindCmpCond (const char* Code, unsigned CodeLen) -/* Search for a compare condition by the given code using the given length */ -{ - unsigned I; - - /* Linear search */ - for (I = 0; I < sizeof (CmpSuffixTab) / sizeof (CmpSuffixTab [0]); ++I) { - if (strncmp (Code, CmpSuffixTab [I], CodeLen) == 0) { - /* Found */ - return I; - } - } - - /* Not found */ - return CMP_INV; -} - - - -static cmp_t FindBoolCmpCond (const char* Name) -/* Map a condition suffix to a code. Return the code or CMP_INV on failure */ -{ - /* Check for the correct subroutine name */ - if (strncmp (Name, "bool", 4) == 0) { - /* Name is ok, search for the code in the table */ - return FindCmpCond (Name+4, strlen(Name)-4); - } else { - /* Not found */ - return CMP_INV; - } -} - - - -static cmp_t FindTosCmpCond (const char* Name) -/* Check if this is a call to one of the TOS compare functions (tosgtax). - * Return the condition code or CMP_INV on failure. - */ -{ - unsigned Len = strlen (Name); - - /* Check for the correct subroutine name */ - if (strncmp (Name, "tos", 3) == 0 && strcmp (Name+Len-2, "ax") == 0) { - /* Name is ok, search for the code in the table */ - return FindCmpCond (Name+3, Len-3-2); - } else { - /* Not found */ - return CMP_INV; - } -} - - - static void ReplaceCmp (CodeSeg* S, unsigned I, cmp_t Cond) /* Helper function for the replacement of routines that return a boolean * followed by a conditional jump. Instead of the boolean value, the condition @@ -283,63 +210,6 @@ static int GetCmpRegVal (const CodeEntry* E) -static int IsCmpToZero (const CodeEntry* E) -/* Check if the given instrcuction is a compare to zero instruction */ -{ - return (E->OPC == OP65_CMP && - E->AM == AM65_IMM && - (E->Flags & CEF_NUMARG) != 0 && - E->Num == 0); -} - - - -static int IsSpLoad (const CodeEntry* E) -/* Return true if this is the load of A from the stack */ -{ - return E->OPC == OP65_LDA && E->AM == AM65_ZP_INDY && strcmp (E->Arg, "sp") == 0; -} - - - -static int IsLocalLoad16 (CodeSeg* S, unsigned Index, - CodeEntry** L, unsigned Count) -/* Check if a 16 bit load of a local variable follows: - * - * ldy #$xx - * lda (sp),y - * tax - * dey - * lda (sp),y - * - * If so, read Count entries following the first ldy into L and return true - * if this is possible. Otherwise return false. - */ -{ - /* Be sure we read enough entries for the check */ - CHECK (Count >= 5); - - /* Read the first entry */ - L[0] = CS_GetEntry (S, Index); - - /* Check for the sequence */ - return (L[0]->OPC == OP65_LDY && - CE_KnownImm (L[0]) && - CS_GetEntries (S, L+1, Index+1, Count-1) && - IsSpLoad (L[1]) && - !CE_HasLabel (L[1]) && - L[2]->OPC == OP65_TAX && - !CE_HasLabel (L[2]) && - L[3]->OPC == OP65_LDY && - CE_KnownImm (L[3]) && - L[3]->Num == L[0]->Num - 1 && - !CE_HasLabel (L[3]) && - IsSpLoad (L[4]) && - !CE_HasLabel (L[4])); -} - - - /*****************************************************************************/ /* Remove calls to the bool transformer subroutines */ /*****************************************************************************/ @@ -434,13 +304,12 @@ unsigned OptCmp1 (CodeSeg* S) /* Check for the sequence */ if (E->OPC == OP65_STX && + !CS_RangeHasLabel (S, I+1, 2) && CS_GetEntries (S, L, I+1, 2) && L[0]->OPC == OP65_STX && strcmp (L[0]->Arg, "tmp1") == 0 && - !CE_HasLabel (L[0]) && L[1]->OPC == OP65_ORA && - strcmp (L[1]->Arg, "tmp1") == 0 && - !CE_HasLabel (L[1])) { + strcmp (L[1]->Arg, "tmp1") == 0) { /* Remove the remaining instructions */ CS_DelEntries (S, I+1, 2); @@ -484,37 +353,93 @@ unsigned OptCmp2 (CodeSeg* S) unsigned I = 0; while (I < CS_GetEntryCount (S)) { - CodeEntry* L[2]; + CodeEntry* L[3]; /* Get next entry */ - CodeEntry* E = CS_GetEntry (S, I); + L[0] = CS_GetEntry (S, I); /* Check for the sequence */ - if ((E->OPC == OP65_ADC || - E->OPC == OP65_AND || - E->OPC == OP65_DEA || - E->OPC == OP65_EOR || - E->OPC == OP65_INA || - E->OPC == OP65_LDA || - E->OPC == OP65_ORA || - E->OPC == OP65_PLA || - E->OPC == OP65_SBC || - E->OPC == OP65_TXA || - E->OPC == OP65_TYA) && - CS_GetEntries (S, L, I+1, 2) && - IsCmpToZero (L[0]) && - !CE_HasLabel (L[0]) && - ((L[1]->Info & OF_FBRA) != 0 || - (L[1]->OPC == OP65_JSR && - FindBoolCmpCond (L[1]->Arg) != CMP_INV)) && - !CE_HasLabel (L[1])) { - - /* Remove the compare */ - CS_DelEntry (S, I+1); + if ((L[0]->OPC == OP65_ADC || + L[0]->OPC == OP65_AND || + L[0]->OPC == OP65_DEA || + L[0]->OPC == OP65_EOR || + L[0]->OPC == OP65_INA || + L[0]->OPC == OP65_LDA || + L[0]->OPC == OP65_ORA || + L[0]->OPC == OP65_PLA || + L[0]->OPC == OP65_SBC || + L[0]->OPC == OP65_TXA || + L[0]->OPC == OP65_TYA) && + !CS_RangeHasLabel (S, I+1, 2) && + CS_GetEntries (S, L+1, I+1, 2) && + L[1]->OPC == OP65_CMP && + CE_KnownImm (L[1]) && + L[1]->Num == 0) { + + /* Check for the call to boolxx. We cannot remove the compare if + * the carry flag is evaluated later, because the load will not + * set the carry flag. + */ + if (L[2]->OPC == OP65_JSR) { + switch (FindBoolCmpCond (L[2]->Arg)) { + + case CMP_EQ: + case CMP_NE: + case CMP_GT: + case CMP_GE: + case CMP_LT: + case CMP_LE: + /* Remove the compare */ + CS_DelEntry (S, I+1); + ++Changes; + break; + + case CMP_UGT: + case CMP_UGE: + case CMP_ULT: + case CMP_ULE: + case CMP_INV: + /* Leave it alone */ + break; + } - /* Remember, we had changes */ - ++Changes; + } else { + /* Check for a branch on conditions that are set by the load. + * Beware: The insn may branch to another conditional branch + * that evaluates other flags, so check that. + */ + CodeEntry* E = L[2]; + int Delete = 0; + while (1) { + if ((E->Info & (OF_CBRA|OF_UBRA)) != 0) { + /* A conditional branch. Check if it jumps on a + * condition not set by the load. + */ + if ((E->Info & (OF_FBRA|OF_UBRA)) == 0) { + /* Invalid branch */ + break; + } else if (E->JumpTo == 0) { + /* Jump to external */ + Delete = 1; + break; + } else { + /* Check target of branch */ + E = E->JumpTo->Owner; + } + } else { + /* Some other insn */ + Delete = 1; + break; + } + } + + /* Delete the compare if we can */ + if (Delete) { + CS_DelEntry (S, I+1); + ++Changes; + } + } } /* Next entry */ @@ -562,7 +487,7 @@ unsigned OptCmp3 (CodeSeg* S) /* Check for the sequence */ if (E->OPC == OP65_LDA && - CS_GetEntries (S, L, I+1, 5) && + CS_GetEntries (S, L, I+1, 5) && L[0]->OPC == OP65_LDX && !CE_HasLabel (L[0]) && IsImmCmp16 (L+1) && @@ -610,10 +535,7 @@ unsigned OptCmp4 (CodeSeg* S) /* Optimize compares of local variables: * * ldy #o - * lda (sp),y - * tax - * dey - * lda (sp),y + * jsr ldaxysp * cpx #a * bne L1 * cmp #b @@ -626,26 +548,52 @@ unsigned OptCmp4 (CodeSeg* S) unsigned I = 0; while (I < CS_GetEntryCount (S)) { - CodeEntry* L[9]; + CodeEntry* L[6]; + + /* Get the next entry */ + L[0] = CS_GetEntry (S, I); /* Check for the sequence */ - if (IsLocalLoad16 (S, I, L, 9) && IsImmCmp16 (L+5)) { + if (L[0]->OPC == OP65_LDY && + CE_KnownImm (L[0]) && + CS_GetEntries (S, L+1, I+1, 5) && + !CE_HasLabel (L[1]) && + CE_IsCallTo (L[1], "ldaxysp") && + IsImmCmp16 (L+2)) { - if ((L[8]->Info & OF_FBRA) != 0 && L[5]->Num == 0 && L[7]->Num == 0) { + if ((L[5]->Info & OF_FBRA) != 0 && L[2]->Num == 0 && L[4]->Num == 0) { - /* The value is zero, we may use the simple code version: - * ldy #o - * lda (sp),y + CodeEntry* X; + char Buf[20]; + + /* The value is zero, we may use the simple code version: * ldy #o-1 + * lda (sp),y + * ldy #o * ora (sp),y * jne/jeq ... */ - CE_ReplaceOPC (L[4], OP65_ORA); + sprintf (Buf, "$%02X", (int)(L[0]->Num-1)); + X = NewCodeEntry (OP65_LDY, AM65_IMM, Buf, 0, L[0]->LI); + CS_InsertEntry (S, X, I+1); + + X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI); + CS_InsertEntry (S, X, I+2); + + X = NewCodeEntry (OP65_LDY, AM65_IMM, L[0]->Arg, 0, L[0]->LI); + CS_InsertEntry (S, X, I+3); + + X = NewCodeEntry (OP65_ORA, AM65_ZP_INDY, "sp", 0, L[1]->LI); + CS_InsertEntry (S, X, I+4); + CS_DelEntries (S, I+5, 3); /* cpx/bne/cmp */ - CS_DelEntry (S, I+2); /* tax */ + CS_DelEntry (S, I); /* ldy */ } else { + CodeEntry* X; + char Buf[20]; + /* Change the code to just use the A register. Move the load * of the low byte after the first branch if possible: * @@ -658,10 +606,23 @@ unsigned OptCmp4 (CodeSeg* S) * cmp #b * jne/jeq ... */ - CS_DelEntry (S, I+2); /* tax */ - CE_ReplaceOPC (L[5], OP65_CMP); /* cpx -> cmp */ - CS_MoveEntry (S, I+4, I+2); /* cmp */ - CS_MoveEntry (S, I+5, I+3); /* bne */ + X = NewCodeEntry (OP65_LDY, AM65_IMM, L[0]->Arg, 0, L[0]->LI); + CS_InsertEntry (S, X, I+3); + + X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI); + CS_InsertEntry (S, X, I+4); + + X = NewCodeEntry (OP65_CMP, L[2]->AM, L[2]->Arg, 0, L[2]->LI); + CS_InsertEntry (S, X, I+5); + + sprintf (Buf, "$%02X", (int)(L[0]->Num-1)); + X = NewCodeEntry (OP65_LDY, AM65_IMM, Buf, 0, L[0]->LI); + CS_InsertEntry (S, X, I+7); + + X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI); + CS_InsertEntry (S, X, I+8); + + CS_DelEntries (S, I, 3); /* ldy/jsr/cpx */ } @@ -901,3 +862,4 @@ NextEntry: +