diff --git a/src/cc65.vcxproj b/src/cc65.vcxproj
index 1015b389f..0f63a1022 100644
--- a/src/cc65.vcxproj
+++ b/src/cc65.vcxproj
@@ -87,6 +87,7 @@
+
@@ -163,6 +164,7 @@
+
diff --git a/src/cc65/codeoptutil.c b/src/cc65/codeoptutil.c
new file mode 100644
index 000000000..999c18d33
--- /dev/null
+++ b/src/cc65/codeoptutil.c
@@ -0,0 +1,993 @@
+/*****************************************************************************/
+/* */
+/* codeoptutil.c */
+/* */
+/* Optimize operations that take operands via the stack */
+/* */
+/* */
+/* */
+/* (C) 2001 Ullrich von Bassewitz */
+/* Wacholderweg 14 */
+/* D-70597 Stuttgart */
+/* EMail: uz@cc65.org */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
+
+
+
+#include
+
+/* common */
+#include "chartype.h"
+#include "xmalloc.h"
+
+/* cc65 */
+#include "codeinfo.h"
+#include "codeoptutil.h"
+#include "error.h"
+
+
+
+/*****************************************************************************/
+/* Load tracking code */
+/*****************************************************************************/
+
+
+
+void ClearLoadRegInfo (LoadRegInfo* RI)
+/* Clear a LoadRegInfo struct */
+{
+ RI->Flags = LI_NONE;
+ RI->LoadIndex = -1;
+ RI->LoadEntry = 0;
+ RI->LoadYIndex = -1;
+ RI->LoadYEntry = 0;
+ RI->XferIndex = -1;
+ RI->XferEntry = 0;
+ RI->Offs = 0;
+}
+
+
+
+void CopyLoadRegInfo (LoadRegInfo* To, LoadRegInfo* From)
+/* Copy a LoadRegInfo struct */
+{
+ To->Flags = From->Flags;
+ To->LoadIndex = From->LoadIndex;
+ To->LoadEntry = From->LoadEntry;
+ To->LoadYIndex = From->LoadYIndex;
+ To->LoadYEntry = From->LoadYEntry;
+ To->XferIndex = From->XferIndex;
+ To->XferEntry = From->XferEntry;
+ To->Offs = From->Offs;
+}
+
+
+
+void FinalizeLoadRegInfo (LoadRegInfo* RI, CodeSeg* S)
+/* Prepare a LoadRegInfo struct for use */
+{
+ /* Get the entries */
+ if (RI->LoadIndex >= 0) {
+ RI->LoadEntry = CS_GetEntry (S, RI->LoadIndex);
+ } else {
+ RI->LoadEntry = 0;
+ }
+ if (RI->XferIndex >= 0) {
+ RI->XferEntry = CS_GetEntry (S, RI->XferIndex);
+ } else {
+ RI->XferEntry = 0;
+ }
+ /* Load from src not modified before op can be treated as direct */
+ if ((RI->Flags & LI_SRC_CHG) == 0 &&
+ (RI->Flags & (LI_CHECK_ARG | LI_CHECK_Y)) != 0) {
+ RI->Flags |= LI_DIRECT;
+ if ((RI->Flags & LI_CHECK_Y) != 0) {
+ RI->Flags |= LI_RELOAD_Y;
+ }
+ }
+ /* We cannot ldy src,y */
+ if ((RI->Flags & LI_RELOAD_Y) != 0 &&
+ RI->LoadYEntry != 0 &&
+ (RI->LoadYEntry->Use & REG_Y) == REG_Y) {
+ RI->Flags &= ~LI_DIRECT;
+ }
+}
+
+
+
+void AdjustLoadRegInfo (LoadRegInfo* RI, int Index, int Change)
+/* Adjust a load register info struct after deleting or inserting an entry
+** with a given index
+*/
+{
+ CHECK (abs (Change) == 1);
+ if (Change < 0) {
+ /* Deletion */
+ if (Index < RI->LoadIndex) {
+ --RI->LoadIndex;
+ } else if (Index == RI->LoadIndex) {
+ /* Has been removed */
+ RI->LoadIndex = -1;
+ RI->LoadEntry = 0;
+ }
+ if (Index < RI->XferIndex) {
+ --RI->XferIndex;
+ } else if (Index == RI->XferIndex) {
+ /* Has been removed */
+ RI->XferIndex = -1;
+ RI->XferEntry = 0;
+ }
+ } else {
+ /* Insertion */
+ if (Index <= RI->LoadIndex) {
+ ++RI->LoadIndex;
+ }
+ if (Index <= RI->XferIndex) {
+ ++RI->XferIndex;
+ }
+ }
+}
+
+
+
+void ClearLoadInfo (LoadInfo* LI)
+/* Clear a LoadInfo struct */
+{
+ ClearLoadRegInfo (&LI->A);
+ ClearLoadRegInfo (&LI->X);
+ ClearLoadRegInfo (&LI->Y);
+}
+
+
+
+void CopyLoadInfo (LoadInfo* To, LoadInfo* From)
+/* Copy a LoadInfo struct */
+{
+ CopyLoadRegInfo (&To->A, &From->A);
+ CopyLoadRegInfo (&To->X, &From->X);
+ CopyLoadRegInfo (&To->Y, &From->Y);
+}
+
+
+
+void FinalizeLoadInfo (LoadInfo* LI, CodeSeg* S)
+/* Prepare a LoadInfo struct for use */
+{
+ /* Get the entries */
+ FinalizeLoadRegInfo (&LI->A, S);
+ FinalizeLoadRegInfo (&LI->X, S);
+ FinalizeLoadRegInfo (&LI->Y, S);
+}
+
+
+
+void AdjustLoadInfo (LoadInfo* LI, int Index, int Change)
+/* Adjust a load info struct after deleting entry with a given index */
+{
+ AdjustLoadRegInfo (&LI->A, Index, Change);
+ AdjustLoadRegInfo (&LI->X, Index, Change);
+ AdjustLoadRegInfo (&LI->Y, Index, Change);
+}
+
+
+
+RegInfo* GetLastChangedRegInfo (StackOpData* D, LoadRegInfo* Reg)
+/* Get RegInfo of the last load insn entry */
+{
+ CodeEntry* E;
+
+ if (Reg->LoadIndex >= 0 && (E = CS_GetEntry (D->Code, Reg->LoadIndex)) != 0) {
+ return E->RI;
+ }
+
+ return 0;
+}
+
+
+
+static int Affected (LoadRegInfo* RI, const CodeEntry* E)
+/* Check if the load src may be modified between the pushax and op */
+{
+ fncls_t fncls;
+ unsigned int Use;
+ unsigned int Chg;
+ unsigned int UseToCheck = 0;
+
+ if ((RI->Flags & (LI_CHECK_ARG | LI_CHECK_Y)) != 0) {
+ if (E->AM == AM65_IMM || E->AM == AM65_ACC || E->AM == AM65_IMP || E->AM == AM65_BRA) {
+ return 0;
+ }
+ CHECK ((RI->Flags & LI_CHECK_ARG) == 0 || RI->LoadEntry != 0);
+ CHECK ((RI->Flags & LI_CHECK_Y) == 0 || RI->LoadYEntry != 0);
+
+ if ((RI->Flags & LI_CHECK_ARG) != 0) {
+ UseToCheck |= RI->LoadEntry->Use;
+ }
+
+ if ((RI->Flags & LI_CHECK_Y) != 0) {
+ UseToCheck |= RI->LoadYEntry->Use;
+ }
+
+ if (E->OPC == OP65_JSR) {
+ /* Try to know about the function */
+ fncls = GetFuncInfo (E->Arg, &Use, &Chg);
+ if ((UseToCheck & Chg & REG_ALL) == 0 &&
+ fncls == FNCLS_BUILTIN) {
+ /* Builtin functions are known to be harmless */
+ return 0;
+ }
+ /* Otherwise play it safe */
+ return 1;
+ } else if (E->OPC == OP65_DEC || E->OPC == OP65_INC ||
+ E->OPC == OP65_ASL || E->OPC == OP65_LSR ||
+ E->OPC == OP65_ROL || E->OPC == OP65_ROR ||
+ E->OPC == OP65_TRB || E->OPC == OP65_TSB ||
+ E->OPC == OP65_STA || E->OPC == OP65_STX || E->OPC == OP65_STY) {
+ if ((E->AM == AM65_ABS || E->AM == AM65_ZP)) {
+ if ((RI->Flags & LI_CHECK_ARG) != 0 &&
+ strcmp (RI->LoadEntry->Arg, E->Arg) == 0) {
+ return 1;
+ }
+ if ((RI->Flags & LI_CHECK_Y) != 0 &&
+ strcmp (RI->LoadYEntry->Arg, E->Arg) == 0) {
+ return 1;
+ }
+ return 0;
+ }
+ /* We could've check further for more cases where the load target isn't modified,
+ ** But for now let's save the trouble and just play it safe. */
+ return 1;
+ }
+ }
+ return 0;
+}
+
+
+
+static void HonourUseAndChg (LoadRegInfo* RI, unsigned Reg, const CodeEntry* E, int I)
+/* Honour use and change flags for an instruction */
+{
+ if ((E->Chg & Reg) != 0) {
+ /* Remember this as an indirect load */
+ ClearLoadRegInfo (RI);
+ RI->LoadIndex = I;
+ RI->XferIndex = -1;
+ RI->Flags = 0;
+ } else if (Affected (RI, E)) {
+ RI->Flags |= LI_SRC_CHG;
+ }
+}
+
+
+
+unsigned int TrackLoads (LoadInfo* LI, LoadInfo* LLI, CodeSeg* S, int I)
+/* Track loads for a code entry.
+** Return used registers.
+*/
+{
+ unsigned Used;
+ CodeEntry* E = CS_GetEntry (S, I);
+ CHECK (E != 0);
+
+ /* By default */
+ Used = E->Use;
+
+ /* Whether we had a load or xfer op before or not, the newly loaded value
+ ** will be the real one used for the pushax/op unless it's overwritten,
+ ** so we can just reset the flags about it in such cases.
+ */
+ if (E->Info & OF_LOAD) {
+
+ LoadRegInfo* RI = 0;
+
+ /* Determine, which register was loaded */
+ if (E->Chg & REG_A) {
+ RI = &LI->A;
+ } else if (E->Chg & REG_X) {
+ RI = &LI->X;
+ } else if (E->Chg & REG_Y) {
+ RI = &LI->Y;
+ }
+ CHECK (RI != 0);
+
+ /* Remember the load */
+ RI->LoadIndex = I;
+ RI->XferIndex = -1;
+
+ /* Set load flags */
+ RI->Flags = LI_LOAD_INSN;
+ if (E->AM == AM65_IMM) {
+ /* These insns are all ok and replaceable */
+ RI->Flags |= LI_DIRECT;
+ } else if (E->AM == AM65_ZP || E->AM == AM65_ABS) {
+ /* These insns are replaceable only if they are not modified later */
+ RI->Flags |= LI_CHECK_ARG;
+ } else if (E->AM == AM65_ZPY || E->AM == AM65_ABSY) {
+ /* These insns are replaceable only if they are not modified later */
+ RI->Flags |= LI_CHECK_ARG | LI_CHECK_Y;
+ } else if (E->AM == AM65_ZP_INDY &&
+ strcmp (E->Arg, "sp") == 0) {
+ /* A load from the stack with known offset is also ok, but in this
+ ** case we must reload the index register later. Please note that
+ ** a load indirect via other zero page locations is not ok, since
+ ** these locations may change between the push and the actual
+ ** operation.
+ */
+ RI->Flags |= LI_DIRECT | LI_CHECK_Y | LI_SP;
+
+ /* Reg Y can be regarded as unused if this load is removed */
+ Used &= ~REG_Y;
+ if (RI == &LI->A) {
+ LI->Y.Flags |= LI_USED_BY_A;
+ } else {
+ LI->Y.Flags |= LI_USED_BY_X;
+ }
+ }
+
+ /* If the load offset has a known value, we can just remember and reload
+ ** it into the index register later.
+ */
+ if ((RI->Flags & LI_CHECK_Y) != 0) {
+ if (RegValIsKnown (E->RI->In.RegY)) {
+ RI->Offs = (unsigned char)E->RI->In.RegY;
+ RI->Flags &= ~LI_CHECK_Y;
+ RI->Flags |= LI_RELOAD_Y;
+ } else {
+ /* We need to check if the src of Y is changed */
+ RI->LoadYIndex = LI->Y.LoadIndex;
+ RI->LoadYEntry = CS_GetEntry (S, RI->LoadYIndex);
+ }
+ }
+
+ /* Watch for any change of the load target */
+ if ((RI->Flags & LI_CHECK_ARG) != 0) {
+ RI->LoadEntry = CS_GetEntry (S, I);
+ }
+
+ } else if (E->Info & OF_XFR) {
+
+ /* Determine source and target of the transfer and handle the TSX insn */
+ LoadRegInfo* Src;
+ LoadRegInfo* Tgt;
+ switch (E->OPC) {
+ case OP65_TAX:
+ Src = &LI->A;
+ Tgt = &LI->X;
+ Used &= ~REG_A;
+ Src->Flags |= LI_USED_BY_X;
+ break;
+ case OP65_TAY:
+ Src = &LI->A;
+ Tgt = &LI->Y;
+ Used &= ~REG_A;
+ Src->Flags |= LI_USED_BY_Y;
+ break;
+ case OP65_TXA:
+ Src = &LI->X;
+ Tgt = &LI->A;
+ Used &= ~REG_X;
+ Src->Flags |= LI_USED_BY_A;
+ break;
+ case OP65_TYA:
+ Src = &LI->Y;
+ Tgt = &LI->A;
+ Used &= ~REG_Y;
+ Src->Flags |= LI_USED_BY_A;
+ break;
+ case OP65_TSX:
+ ClearLoadRegInfo (&LI->X);
+ return Used;
+ case OP65_TXS:
+ return Used;
+ default: Internal ("Unknown XFR insn in TrackLoads");
+ }
+
+ /* Transfer the data */
+ Tgt->LoadIndex = Src->LoadIndex;
+ Tgt->LoadEntry = Src->LoadEntry;
+ Tgt->LoadYIndex = Src->LoadYIndex;
+ Tgt->LoadYEntry = Src->LoadYEntry;
+ Tgt->XferIndex = I;
+ Tgt->Offs = Src->Offs;
+ Tgt->Flags = Src->Flags;
+
+ } else if (CE_IsCallTo (E, "ldaxysp") && RegValIsKnown (E->RI->In.RegY)) {
+
+ /* Both registers set, Y changed */
+ LI->A.LoadIndex = I;
+ LI->A.XferIndex = -1;
+ LI->A.Flags = (LI_LOAD_INSN | LI_DIRECT | LI_RELOAD_Y | LI_SP);
+ LI->A.Offs = (unsigned char) E->RI->In.RegY - 1;
+
+ LI->X.LoadIndex = I;
+ LI->X.XferIndex = -1;
+ LI->X.Flags = (LI_LOAD_INSN | LI_DIRECT | LI_RELOAD_Y | LI_SP);
+ LI->X.Offs = (unsigned char) E->RI->In.RegY;
+
+ /* Reg Y can be regarded as unused if this load is removed */
+ Used &= ~REG_Y;
+ LI->Y.Flags |= LI_USED_BY_A | LI_USED_BY_X;
+
+ } else {
+ HonourUseAndChg (&LI->A, REG_A, E, I);
+ HonourUseAndChg (&LI->X, REG_X, E, I);
+ HonourUseAndChg (&LI->Y, REG_Y, E, I);
+
+ /* The other operand may be affected too */
+ if (LLI != 0) {
+ if (Affected (&LLI->A, E)) {
+ LLI->A.Flags |= LI_SRC_CHG;
+ }
+ if (Affected (&LLI->X, E)) {
+ LLI->X.Flags |= LI_SRC_CHG;
+ }
+ if (Affected (&LLI->Y, E)) {
+ LLI->Y.Flags |= LI_SRC_CHG;
+ }
+ }
+ }
+
+ return Used;
+}
+
+
+
+void SetDontRemoveEntryFlag (LoadRegInfo* RI)
+/* Flag the entry as non-removable according to register flags */
+{
+ if (RI->Flags & LI_DONT_REMOVE) {
+ if (RI->LoadEntry != 0) {
+ RI->LoadEntry->Flags |= CEF_DONT_REMOVE;
+ }
+ }
+}
+
+
+
+void ResetDontRemoveEntryFlag (LoadRegInfo* RI)
+/* Unflag the entry as non-removable according to register flags */
+{
+ if (RI->Flags & LI_DONT_REMOVE) {
+ if (RI->LoadEntry != 0) {
+ RI->LoadEntry->Flags &= ~CEF_DONT_REMOVE;
+ }
+ }
+}
+
+
+
+void SetDontRemoveEntryFlags (StackOpData* D)
+/* Flag the entries as non-removable according to register flags */
+{
+ SetDontRemoveEntryFlag (&D->Lhs.A);
+ SetDontRemoveEntryFlag (&D->Lhs.X);
+ SetDontRemoveEntryFlag (&D->Rhs.A);
+ SetDontRemoveEntryFlag (&D->Rhs.X);
+}
+
+
+
+void ResetDontRemoveEntryFlags (StackOpData* D)
+/* Unflag the entries as non-removable according to register flags */
+{
+ ResetDontRemoveEntryFlag (&D->Lhs.A);
+ ResetDontRemoveEntryFlag (&D->Lhs.X);
+ ResetDontRemoveEntryFlag (&D->Rhs.A);
+ ResetDontRemoveEntryFlag (&D->Rhs.X);
+}
+
+
+
+void ResetStackOpData (StackOpData* Data)
+/* Reset the given data structure */
+{
+ Data->OptFunc = 0;
+ Data->ZPUsage = REG_NONE;
+ Data->ZPChanged = REG_NONE;
+ Data->UsedRegs = REG_NONE;
+ Data->RhsMultiChg = 0;
+
+ ClearLoadInfo (&Data->Lhs);
+ ClearLoadInfo (&Data->Rhs);
+
+ Data->PushIndex = -1;
+ Data->OpIndex = -1;
+}
+
+
+
+/*****************************************************************************/
+/* Helpers */
+/*****************************************************************************/
+
+
+
+void InsertEntry (StackOpData* D, CodeEntry* E, int Index)
+/* Insert a new entry. Depending on Index, D->PushIndex and D->OpIndex will
+** be adjusted by this function.
+*/
+{
+ /* Insert the entry into the code segment */
+ CS_InsertEntry (D->Code, E, Index);
+
+ /* Adjust register loads if necessary */
+ AdjustLoadInfo (&D->Lhs, Index, 1);
+ AdjustLoadInfo (&D->Rhs, Index, 1);
+
+ /* Adjust the indices if necessary */
+ if (D->PushEntry && Index <= D->PushIndex) {
+ ++D->PushIndex;
+ }
+ if (D->OpEntry && Index <= D->OpIndex) {
+ ++D->OpIndex;
+ }
+}
+
+
+
+void DelEntry (StackOpData* D, int Index)
+/* Delete an entry. Depending on Index, D->PushIndex and D->OpIndex will be
+** adjusted by this function, and PushEntry/OpEntry may get invalidated.
+*/
+{
+ /* Delete the entry from the code segment */
+ CS_DelEntry (D->Code, Index);
+
+ /* Adjust register loads if necessary */
+ AdjustLoadInfo (&D->Lhs, Index, -1);
+ AdjustLoadInfo (&D->Rhs, Index, -1);
+
+ /* Adjust the other indices if necessary */
+ if (Index < D->PushIndex) {
+ --D->PushIndex;
+ } else if (Index == D->PushIndex) {
+ D->PushEntry = 0;
+ }
+ if (Index < D->OpIndex) {
+ --D->OpIndex;
+ } else if (Index == D->OpIndex) {
+ D->OpEntry = 0;
+ }
+}
+
+
+
+void AdjustStackOffset (StackOpData* D, unsigned Offs)
+/* Adjust the offset for all stack accesses in the range PushIndex to OpIndex.
+** OpIndex is adjusted according to the insertions.
+*/
+{
+ /* Walk over all entries */
+ int I = D->PushIndex + 1;
+ while (I < D->OpIndex) {
+
+ CodeEntry* E = CS_GetEntry (D->Code, I);
+
+ /* Check if this entry does a stack access, and if so, if it's a plain
+ ** load from stack, since this is needed later.
+ */
+ int Correction = 0;
+ if ((E->Use & REG_SP) != 0) {
+
+ /* Check for some things that should not happen */
+ CHECK (E->AM == AM65_ZP_INDY || E->RI->In.RegY >= (short) Offs);
+ CHECK (strcmp (E->Arg, "sp") == 0);
+ /* We need to correct this one */
+ Correction = (E->OPC == OP65_LDA)? 2 : 1;
+
+ } else if (CE_IsCallTo (E, "ldaxysp")) {
+ /* We need to correct this one */
+ Correction = 1;
+ }
+
+ if (Correction) {
+ /* Get the code entry before this one. If it's a LDY, adjust the
+ ** value.
+ */
+ CodeEntry* P = CS_GetPrevEntry (D->Code, I);
+ if (P && P->OPC == OP65_LDY && CE_IsConstImm (P)) {
+ /* The Y load is just before the stack access, adjust it */
+ CE_SetNumArg (P, P->Num - Offs);
+ } else {
+ /* Insert a new load instruction before the stack access */
+ const char* Arg = MakeHexArg (E->RI->In.RegY - Offs);
+ CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
+ InsertEntry (D, X, I++);
+ }
+
+ /* If we need the value of Y later, be sure to reload it */
+ if (RegYUsed (D->Code, I+1)) {
+ CodeEntry* N;
+ const char* Arg = MakeHexArg (E->RI->In.RegY);
+ if (Correction == 2 && (N = CS_GetNextEntry(D->Code, I)) != 0 &&
+ ((N->Info & OF_ZBRA) != 0) && N->JumpTo != 0) {
+ /* The Y register is used but the load instruction loads A
+ ** and is followed by a branch that evaluates the zero flag.
+ ** This means that we cannot just insert the load insn
+ ** for the Y register at this place, because it would
+ ** destroy the Z flag. Instead place load insns at the
+ ** target of the branch and after it.
+ ** Note: There is a chance that this code won't work. The
+ ** jump may be a backwards jump (in which case the stack
+ ** offset has already been adjusted) or there may be other
+ ** instructions between the load and the conditional jump.
+ ** Currently the compiler does not generate such code, but
+ ** it is possible to force the optimizer into something
+ ** invalid by use of inline assembler.
+ */
+
+ /* Add load insn after the branch */
+ CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
+ InsertEntry (D, X, I+2);
+
+ /* Add load insn before branch target */
+ CodeEntry* Y = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
+ int J = CS_GetEntryIndex (D->Code, N->JumpTo->Owner);
+ CHECK (J > I); /* Must not happen */
+ InsertEntry (D, Y, J);
+
+ /* Move the label to the new insn */
+ CodeLabel* L = CS_GenLabel (D->Code, Y);
+ CS_MoveLabelRef (D->Code, N, L);
+ } else {
+ CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
+ InsertEntry (D, X, I+1);
+ /* Skip this instruction in the next round */
+ ++I;
+ }
+ }
+ }
+
+ /* Next entry */
+ ++I;
+ }
+
+ /* If we have rhs load insns that load from stack, we'll have to adjust
+ ** the offsets for these also.
+ */
+ if ((D->Rhs.A.Flags & (LI_RELOAD_Y | LI_SP | LI_CHECK_Y)) == (LI_RELOAD_Y | LI_SP)) {
+ D->Rhs.A.Offs -= Offs;
+ }
+ if ((D->Rhs.X.Flags & (LI_RELOAD_Y | LI_SP | LI_CHECK_Y)) == (LI_RELOAD_Y | LI_SP)) {
+ D->Rhs.X.Offs -= Offs;
+ }
+}
+
+
+
+int IsRegVar (StackOpData* D)
+/* If the value pushed is that of a zeropage variable that is unchanged until Op,
+** 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 be unchanged till Op */
+ if ((D->Lhs.A.Flags & (LI_DIRECT | LI_RELOAD_Y)) != LI_DIRECT ||
+ (D->Lhs.X.Flags & (LI_DIRECT | LI_RELOAD_Y)) != LI_DIRECT) {
+ return 0;
+ }
+
+ /* 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;
+}
+
+
+
+void AddStoreLhsA (StackOpData* D)
+/* Add a store to zero page after the push insn */
+{
+ CodeEntry* X = NewCodeEntry (OP65_STA, AM65_ZP, D->ZPLo, 0, D->PushEntry->LI);
+ InsertEntry (D, X, D->PushIndex+1);
+}
+
+
+
+void AddStoreLhsX (StackOpData* D)
+/* Add a store to zero page after the push insn */
+{
+ CodeEntry* X = NewCodeEntry (OP65_STX, AM65_ZP, D->ZPHi, 0, D->PushEntry->LI);
+ InsertEntry (D, X, D->PushIndex+1);
+}
+
+
+
+void ReplacePushByStore (StackOpData* D)
+/* Replace the call to the push subroutine by a store into the zero page
+** location (actually, the push is not replaced, because we need it for
+** later, but the name is still ok since the push will get removed at the
+** end of each routine).
+*/
+{
+ /* Store the value into the zeropage instead of pushing it. Check high
+ ** byte first so that the store is later in A/X order.
+ */
+ if ((D->Lhs.X.Flags & LI_DIRECT) == 0) {
+ AddStoreLhsX (D);
+ }
+ if ((D->Lhs.A.Flags & LI_DIRECT) == 0) {
+ AddStoreLhsA (D);
+ }
+}
+
+
+
+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 {
+
+ if ((LI->A.Flags & LI_CHECK_Y) == 0) {
+ /* ldy #offs */
+ X = NewCodeEntry (OP65_LDY, AM65_IMM, MakeHexArg (LI->A.Offs), 0, D->OpEntry->LI);
+ } else {
+ /* ldy src */
+ X = NewCodeEntry (OP65_LDY, LI->A.LoadYEntry->AM, LI->A.LoadYEntry->Arg, 0, D->OpEntry->LI);
+ }
+ InsertEntry (D, X, D->IP++);
+
+ if (LI->A.LoadEntry->OPC == OP65_JSR) {
+ /* opc (sp),y */
+ X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
+ } else {
+ /* opc src,y */
+ X = NewCodeEntry (OPC, LI->A.LoadEntry->AM, LI->A.LoadEntry->Arg, 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++);
+
+ }
+}
+
+
+
+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 {
+
+ if ((LI->A.Flags & LI_CHECK_Y) == 0) {
+ /* ldy #const */
+ X = NewCodeEntry (OP65_LDY, AM65_IMM, MakeHexArg (LI->X.Offs), 0, D->OpEntry->LI);
+ } else {
+ /* ldy src */
+ X = NewCodeEntry (OP65_LDY, LI->X.LoadYEntry->AM, LI->X.LoadYEntry->Arg, 0, D->OpEntry->LI);
+ }
+ InsertEntry (D, X, D->IP++);
+
+ if (LI->X.LoadEntry->OPC == OP65_JSR) {
+ /* opc (sp),y */
+ X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
+ } else {
+ /* opc src,y */
+ X = NewCodeEntry (OPC, LI->A.LoadEntry->AM, LI->A.LoadEntry->Arg, 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++);
+ }
+}
+
+
+
+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_REMOVE) {
+ if (LI->A.LoadIndex >= 0 &&
+ (LI->A.LoadEntry->Flags & CEF_DONT_REMOVE) == 0) {
+ DelEntry (D, LI->A.LoadIndex);
+ }
+ if (LI->A.XferIndex >= 0 &&
+ (LI->A.XferEntry->Flags & CEF_DONT_REMOVE) == 0) {
+ DelEntry (D, LI->A.XferIndex);
+ }
+ }
+ if ((LI->X.Flags & LI_REMOVE) == LI_REMOVE) {
+ if (LI->X.LoadIndex >= 0 &&
+ (LI->X.LoadEntry->Flags & CEF_DONT_REMOVE) == 0) {
+ DelEntry (D, LI->X.LoadIndex);
+ }
+ if (LI->X.XferIndex >= 0 &&
+ (LI->X.XferEntry->Flags & CEF_DONT_REMOVE) == 0) {
+ DelEntry (D, LI->X.XferIndex);
+ }
+ }
+}
+
+
+
+void RemoveRemainders (StackOpData* D)
+/* Remove the code that is unnecessary after translation of the sequence */
+{
+ /* Remove the register loads for lhs and rhs if nothing prevents that */
+ 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 CmpHarmless (const void* Key, const void* Entry)
+/* Compare function for bsearch */
+{
+ return strcmp (Key, *(const char**)Entry);
+}
+
+
+
+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.
+*/
+{
+ const char* const Tab[] = {
+ "aslax1",
+ "aslax2",
+ "aslax3",
+ "aslax4",
+ "aslaxy",
+ "asrax1",
+ "asrax2",
+ "asrax3",
+ "asrax4",
+ "asraxy",
+ "bcastax",
+ "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);
+}
+
+
diff --git a/src/cc65/codeoptutil.h b/src/cc65/codeoptutil.h
new file mode 100644
index 000000000..49a8ce60f
--- /dev/null
+++ b/src/cc65/codeoptutil.h
@@ -0,0 +1,257 @@
+/*****************************************************************************/
+/* */
+/* codeoptutil.h */
+/* */
+/* Optimize operations that take operands via the stack */
+/* */
+/* */
+/* */
+/* (C) 2001 Ullrich von Bassewitz */
+/* Wacholderweg 14 */
+/* D-70597 Stuttgart */
+/* EMail: uz@cc65.org */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
+
+
+
+#ifndef CODEOPTUTIL_H
+#define CODEOPTUTIL_H
+
+
+
+/* cc65 */
+#include "codeent.h"
+#include "codeseg.h"
+
+
+
+/*****************************************************************************/
+/* Load tracking data */
+/*****************************************************************************/
+
+
+
+/* LoadRegInfo flags set by DirectOp */
+typedef enum {
+ LI_NONE = 0x00,
+ LI_DIRECT = 0x01, /* Direct op may be used */
+ LI_RELOAD_Y = 0x02, /* Reload index register Y */
+ LI_REMOVE = 0x04, /* Load may be removed */
+ LI_DONT_REMOVE = 0x08, /* Load may not be removed */
+ LI_CHECK_ARG = 0x10, /* Load src might be modified later */
+ LI_SRC_CHG = 0x20, /* Load src is possibly modified */
+ LI_LOAD_INSN = 0x40, /* Has a load insn */
+ LI_CHECK_Y = 0x80, /* Indexed load src might be modified later */
+ LI_USED_BY_A = 0x100, /* Content used by RegA */
+ LI_USED_BY_X = 0x200, /* Content used by RegX */
+ LI_USED_BY_Y = 0x400, /* Content used by RegY */
+ LI_SP = 0x800, /* Content on stack */
+} LI_FLAGS;
+
+/* Structure that tells us how to load the lhs values */
+typedef struct LoadRegInfo LoadRegInfo;
+struct LoadRegInfo {
+ LI_FLAGS Flags; /* Tells us how to load */
+ int LoadIndex; /* Index of load insn, -1 if invalid */
+ CodeEntry* LoadEntry; /* The actual entry, 0 if invalid */
+ int LoadYIndex; /* Index of Y-load insn, -1 if invalid */
+ CodeEntry* LoadYEntry; /* The actual Y-load entry, 0 if invalid */
+ int XferIndex; /* Index of transfer insn */
+ CodeEntry* XferEntry; /* The actual transfer entry */
+ int Offs; /* Stack offset if data is on stack */
+};
+
+/* Now combined for both registers */
+typedef struct LoadInfo LoadInfo;
+struct LoadInfo {
+ LoadRegInfo A; /* Info for A register */
+ LoadRegInfo X; /* Info for X register */
+ LoadRegInfo Y; /* Info for Y register */
+};
+
+/* Structure forward decl */
+typedef struct StackOpData StackOpData;
+typedef struct OptFuncDesc OptFuncDesc;
+
+/* Structure that holds the needed data */
+struct StackOpData {
+ CodeSeg* Code; /* Pointer to code segment */
+ unsigned Flags; /* Flags to remember things */
+
+ /* Pointer to optimizer subfunction description */
+ const OptFuncDesc* OptFunc;
+
+ /* ZP register usage inside the sequence */
+ unsigned ZPUsage;
+ unsigned ZPChanged;
+
+ /* Freedom of registers inside the sequence */
+ unsigned UsedRegs; /* Registers used */
+
+ /* Whether the rhs is changed multiple times */
+ int RhsMultiChg;
+
+ /* Register load information for lhs and rhs */
+ LoadInfo Lhs;
+ LoadInfo Rhs;
+
+ /* Several indices of insns in the code segment */
+ int PushIndex; /* Index of call to pushax in codeseg */
+ int OpIndex; /* Index of actual operation */
+
+ /* Pointers to insns in the code segment */
+ CodeEntry* PrevEntry; /* Entry before the call to pushax */
+ CodeEntry* PushEntry; /* Pointer to entry with call to pushax */
+ CodeEntry* OpEntry; /* Pointer to entry with op */
+ CodeEntry* NextEntry; /* Entry after the op */
+
+ const char* ZPLo; /* Lo byte of zero page loc to use */
+ const char* ZPHi; /* Hi byte of zero page loc to use */
+ unsigned IP; /* Insertion point used by some routines */
+};
+
+
+
+/*****************************************************************************/
+/* Load tracking code */
+/*****************************************************************************/
+
+
+
+void ClearLoadRegInfo (LoadRegInfo* LRI);
+/* Clear a LoadRegInfo struct */
+
+void CopyLoadRegInfo (LoadRegInfo* To, LoadRegInfo* From);
+/* Copy a LoadRegInfo struct */
+
+void FinalizeLoadRegInfo (LoadRegInfo* LRI, CodeSeg* S);
+/* Prepare a LoadRegInfo struct for use */
+
+void AdjustLoadRegInfo (LoadRegInfo* LRI, int Index, int Change);
+/* Adjust a load register info struct after deleting or inserting an entry
+** with a given index
+*/
+
+void ClearLoadInfo (LoadInfo* LI);
+/* Clear a LoadInfo struct */
+
+void CopyLoadInfo (LoadInfo* To, LoadInfo* From);
+/* Copy a LoadInfo struct */
+
+void FinalizeLoadInfo (LoadInfo* LI, CodeSeg* S);
+/* Prepare a LoadInfo struct for use */
+
+void AdjustLoadInfo (LoadInfo* LI, int Index, int Change);
+/* Adjust a load info struct after deleting entry with a given index */
+
+RegInfo* GetLastChangedRegInfo (StackOpData* D, LoadRegInfo* Reg);
+/* Get RegInfo of the last insn entry that changed the reg */
+
+unsigned int TrackLoads (LoadInfo* LI, LoadInfo* LLI, CodeSeg* S, int I);
+/* Track loads for a code entry.
+** Return used registers.
+*/
+
+void SetDontRemoveEntryFlag (LoadRegInfo* LRI);
+/* Flag the entry as non-removable according to register flags */
+
+void ResetDontRemoveEntryFlag (LoadRegInfo* LRI);
+/* Unflag the entry as non-removable according to register flags */
+
+void SetDontRemoveEntryFlags (StackOpData* D);
+/* Flag the entries as non-removable according to register flags */
+
+void ResetDontRemoveEntryFlags (StackOpData* D);
+/* Unflag the entries as non-removable according to register flags */
+
+void ResetStackOpData (StackOpData* Data);
+/* Reset the given data structure */
+
+
+
+/*****************************************************************************/
+/* Helpers */
+/*****************************************************************************/
+
+
+
+void InsertEntry (StackOpData* D, CodeEntry* E, int Index);
+/* Insert a new entry. Depending on Index, D->PushIndex and D->OpIndex will
+** be adjusted by this function.
+*/
+
+void DelEntry (StackOpData* D, int Index);
+/* Delete an entry. Depending on Index, D->PushIndex and D->OpIndex will be
+** adjusted by this function, and PushEntry/OpEntry may get invalidated.
+*/
+
+void AdjustStackOffset (StackOpData* D, unsigned Offs);
+/* Adjust the offset for all stack accesses in the range PushIndex to OpIndex.
+** OpIndex is adjusted according to the insertions.
+*/
+
+int IsRegVar (StackOpData* D);
+/* If the value pushed is that of a zeropage variable that is unchanged until Op,
+** replace ZPLo and ZPHi in the given StackOpData struct by the variable and return true.
+** Otherwise leave D untouched and return false.
+*/
+
+void AddStoreLhsA (StackOpData* D);
+/* Add a store to zero page after the push insn */
+
+void AddStoreLhsX (StackOpData* D);
+/* Add a store to zero page after the push insn */
+
+void ReplacePushByStore (StackOpData* D);
+/* Replace the call to the push subroutine by a store into the zero page
+** location (actually, the push is not replaced, because we need it for
+** later, but the name is still ok since the push will get removed at the
+** end of each routine).
+*/
+
+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.
+*/
+
+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.
+*/
+
+void RemoveRegLoads (StackOpData* D, LoadInfo* LI);
+/* Remove register load insns */
+
+
+void RemoveRemainders (StackOpData* D);
+/* Remove the code that is unnecessary after translation of the sequence */
+
+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.
+*/
+
+/* End of codeoptutil.h */
+
+#endif
diff --git a/src/cc65/coptstop.c b/src/cc65/coptstop.c
index c31b0ec97..457f9ff1f 100644
--- a/src/cc65/coptstop.c
+++ b/src/cc65/coptstop.c
@@ -41,57 +41,12 @@
/* cc65 */
#include "codeent.h"
#include "codeinfo.h"
+#include "codeoptutil.h"
#include "coptstop.h"
#include "error.h"
-/*****************************************************************************/
-/* Load tracking data */
-/*****************************************************************************/
-
-
-
-/* LoadRegInfo flags set by DirectOp */
-typedef enum {
- LI_NONE = 0x00,
- LI_DIRECT = 0x01, /* Direct op may be used */
- LI_RELOAD_Y = 0x02, /* Reload index register Y */
- LI_REMOVE = 0x04, /* Load may be removed */
- LI_DONT_REMOVE = 0x08, /* Load may not be removed */
- LI_CHECK_ARG = 0x10, /* Load src might be modified later */
- LI_SRC_CHG = 0x20, /* Load src is possibly modified */
- LI_LOAD_INSN = 0x40, /* Has a load insn */
- LI_CHECK_Y = 0x80, /* Indexed load src might be modified later */
- LI_USED_BY_A = 0x100, /* Content used by RegA */
- LI_USED_BY_X = 0x200, /* Content used by RegX */
- LI_USED_BY_Y = 0x400, /* Content used by RegY */
- LI_SP = 0x800, /* Content on stack */
-} LI_FLAGS;
-
-/* Structure that tells us how to load the lhs values */
-typedef struct LoadRegInfo LoadRegInfo;
-struct LoadRegInfo {
- LI_FLAGS Flags; /* Tells us how to load */
- int LoadIndex; /* Index of load insn, -1 if invalid */
- CodeEntry* LoadEntry; /* The actual entry, 0 if invalid */
- int LoadYIndex; /* Index of Y-load insn, -1 if invalid */
- CodeEntry* LoadYEntry; /* The actual Y-load entry, 0 if invalid */
- int XferIndex; /* Index of transfer insn */
- CodeEntry* XferEntry; /* The actual transfer entry */
- int Offs; /* Stack offset if data is on stack */
-};
-
-/* Now combined for both registers */
-typedef struct LoadInfo LoadInfo;
-struct LoadInfo {
- LoadRegInfo A; /* Info for A register */
- LoadRegInfo X; /* Info for X register */
- LoadRegInfo Y; /* Info for Y register */
-};
-
-
-
/*****************************************************************************/
/* Data */
/*****************************************************************************/
@@ -121,9 +76,6 @@ typedef enum {
OP_RHS_REMOVE_DIRECT = 0xC000, /* RHS must be directly removable */
} OP_FLAGS;
-/* Structure forward decl */
-typedef struct StackOpData StackOpData;
-
/* Structure that describes an optimizer subfunction for a specific op */
typedef unsigned (*OptFunc) (StackOpData* D);
typedef struct OptFuncDesc OptFuncDesc;
@@ -134,434 +86,6 @@ struct OptFuncDesc {
OP_FLAGS Flags; /* Flags */
};
-/* Structure that holds the needed data */
-struct StackOpData {
- CodeSeg* Code; /* Pointer to code segment */
- unsigned Flags; /* Flags to remember things */
-
- /* Pointer to optimizer subfunction description */
- const OptFuncDesc* OptFunc;
-
- /* ZP register usage inside the sequence */
- unsigned ZPUsage;
- unsigned ZPChanged;
-
- /* Freedom of registers inside the sequence */
- unsigned UsedRegs; /* Registers used */
-
- /* Whether the rhs is changed multiple times */
- int RhsMultiChg;
-
- /* Register load information for lhs and rhs */
- LoadInfo Lhs;
- LoadInfo Rhs;
-
- /* Several indices of insns in the code segment */
- int PushIndex; /* Index of call to pushax in codeseg */
- int OpIndex; /* Index of actual operation */
-
- /* Pointers to insns in the code segment */
- CodeEntry* PrevEntry; /* Entry before the call to pushax */
- CodeEntry* PushEntry; /* Pointer to entry with call to pushax */
- CodeEntry* OpEntry; /* Pointer to entry with op */
- CodeEntry* NextEntry; /* Entry after the op */
-
- const char* ZPLo; /* Lo byte of zero page loc to use */
- const char* ZPHi; /* Hi byte of zero page loc to use */
- unsigned IP; /* Insertion point used by some routines */
-};
-
-
-
-/*****************************************************************************/
-/* Load tracking code */
-/*****************************************************************************/
-
-
-
-static void ClearLoadRegInfo (LoadRegInfo* RI)
-/* Clear a LoadRegInfo struct */
-{
- RI->Flags = LI_NONE;
- RI->LoadIndex = -1;
- RI->LoadEntry = 0;
- RI->LoadYIndex = -1;
- RI->LoadYEntry = 0;
- RI->XferIndex = -1;
- RI->XferEntry = 0;
- RI->Offs = 0;
-}
-
-
-
-static void CopyLoadRegInfo (LoadRegInfo* To, LoadRegInfo* From)
-/* Copy a LoadRegInfo struct */
-{
- To->Flags = From->Flags;
- To->LoadIndex = From->LoadIndex;
- To->LoadEntry = From->LoadEntry;
- To->LoadYIndex = From->LoadYIndex;
- To->LoadYEntry = From->LoadYEntry;
- To->XferIndex = From->XferIndex;
- To->XferEntry = From->XferEntry;
- To->Offs = From->Offs;
-}
-
-
-
-static void FinalizeLoadRegInfo (LoadRegInfo* RI, CodeSeg* S)
-/* Prepare a LoadRegInfo struct for use */
-{
- /* Get the entries */
- if (RI->LoadIndex >= 0) {
- RI->LoadEntry = CS_GetEntry (S, RI->LoadIndex);
- } else {
- RI->LoadEntry = 0;
- }
- if (RI->XferIndex >= 0) {
- RI->XferEntry = CS_GetEntry (S, RI->XferIndex);
- } else {
- RI->XferEntry = 0;
- }
- /* Load from src not modified before op can be treated as direct */
- if ((RI->Flags & LI_SRC_CHG) == 0 &&
- (RI->Flags & (LI_CHECK_ARG | LI_CHECK_Y)) != 0) {
- RI->Flags |= LI_DIRECT;
- if ((RI->Flags & LI_CHECK_Y) != 0) {
- RI->Flags |= LI_RELOAD_Y;
- }
- }
- /* We cannot ldy src,y */
- if ((RI->Flags & LI_RELOAD_Y) != 0 &&
- RI->LoadYEntry != 0 &&
- (RI->LoadYEntry->Use & REG_Y) == REG_Y) {
- RI->Flags &= ~LI_DIRECT;
- }
-}
-
-
-
-static void ClearLoadInfo (LoadInfo* LI)
-/* Clear a LoadInfo struct */
-{
- ClearLoadRegInfo (&LI->A);
- ClearLoadRegInfo (&LI->X);
- ClearLoadRegInfo (&LI->Y);
-}
-
-
-
-static void CopyLoadInfo (LoadInfo* To, LoadInfo* From)
-/* Copy a LoadInfo struct */
-{
- CopyLoadRegInfo (&To->A, &From->A);
- CopyLoadRegInfo (&To->X, &From->X);
- CopyLoadRegInfo (&To->Y, &From->Y);
-}
-
-
-
-static void AdjustLoadRegInfo (LoadRegInfo* RI, int Index, int Change)
-/* Adjust a load register info struct after deleting or inserting an entry
-** with a given index
-*/
-{
- CHECK (abs (Change) == 1);
- if (Change < 0) {
- /* Deletion */
- if (Index < RI->LoadIndex) {
- --RI->LoadIndex;
- } else if (Index == RI->LoadIndex) {
- /* Has been removed */
- RI->LoadIndex = -1;
- RI->LoadEntry = 0;
- }
- if (Index < RI->XferIndex) {
- --RI->XferIndex;
- } else if (Index == RI->XferIndex) {
- /* Has been removed */
- RI->XferIndex = -1;
- RI->XferEntry = 0;
- }
- } else {
- /* Insertion */
- if (Index <= RI->LoadIndex) {
- ++RI->LoadIndex;
- }
- if (Index <= RI->XferIndex) {
- ++RI->XferIndex;
- }
- }
-}
-
-
-
-static void FinalizeLoadInfo (LoadInfo* LI, CodeSeg* S)
-/* Prepare a LoadInfo struct for use */
-{
- /* Get the entries */
- FinalizeLoadRegInfo (&LI->A, S);
- FinalizeLoadRegInfo (&LI->X, S);
- FinalizeLoadRegInfo (&LI->Y, S);
-}
-
-
-
-static void AdjustLoadInfo (LoadInfo* LI, int Index, int Change)
-/* Adjust a load info struct after deleting entry with a given index */
-{
- AdjustLoadRegInfo (&LI->A, Index, Change);
- AdjustLoadRegInfo (&LI->X, Index, Change);
- AdjustLoadRegInfo (&LI->Y, Index, Change);
-}
-
-
-
-static int Affected (LoadRegInfo* RI, const CodeEntry* E)
-/* Check if the load src may be modified between the pushax and op */
-{
- fncls_t fncls;
- unsigned int Use;
- unsigned int Chg;
- unsigned int UseToCheck = 0;
-
- if ((RI->Flags & (LI_CHECK_ARG | LI_CHECK_Y)) != 0) {
- if (E->AM == AM65_IMM || E->AM == AM65_ACC || E->AM == AM65_IMP || E->AM == AM65_BRA) {
- return 0;
- }
- CHECK ((RI->Flags & LI_CHECK_ARG) == 0 || RI->LoadEntry != 0);
- CHECK ((RI->Flags & LI_CHECK_Y) == 0 || RI->LoadYEntry != 0);
-
- if ((RI->Flags & LI_CHECK_ARG) != 0) {
- UseToCheck |= RI->LoadEntry->Use;
- }
-
- if ((RI->Flags & LI_CHECK_Y) != 0) {
- UseToCheck |= RI->LoadYEntry->Use;
- }
-
- if (E->OPC == OP65_JSR) {
- /* Try to know about the function */
- fncls = GetFuncInfo (E->Arg, &Use, &Chg);
- if ((UseToCheck & Chg & REG_ALL) == 0 &&
- fncls == FNCLS_BUILTIN) {
- /* Builtin functions are known to be harmless */
- return 0;
- }
- /* Otherwise play it safe */
- return 1;
- } else if (E->OPC == OP65_DEC || E->OPC == OP65_INC ||
- E->OPC == OP65_ASL || E->OPC == OP65_LSR ||
- E->OPC == OP65_ROL || E->OPC == OP65_ROR ||
- E->OPC == OP65_TRB || E->OPC == OP65_TSB ||
- E->OPC == OP65_STA || E->OPC == OP65_STX || E->OPC == OP65_STY) {
- if ((E->AM == AM65_ABS || E->AM == AM65_ZP)) {
- if ((RI->Flags & LI_CHECK_ARG) != 0 &&
- strcmp (RI->LoadEntry->Arg, E->Arg) == 0) {
- return 1;
- }
- if ((RI->Flags & LI_CHECK_Y) != 0 &&
- strcmp (RI->LoadYEntry->Arg, E->Arg) == 0) {
- return 1;
- }
- return 0;
- }
- /* We could've check further for more cases where the load target isn't modified,
- ** But for now let's save the trouble and just play it safe. */
- return 1;
- }
- }
- return 0;
-}
-
-
-
-static void HonourUseAndChg (LoadRegInfo* RI, unsigned Reg, const CodeEntry* E, int I)
-/* Honour use and change flags for an instruction */
-{
- if ((E->Chg & Reg) != 0) {
- /* Remember this as an indirect load */
- ClearLoadRegInfo (RI);
- RI->LoadIndex = I;
- RI->XferIndex = -1;
- RI->Flags = 0;
- } else if (Affected (RI, E)) {
- RI->Flags |= LI_SRC_CHG;
- }
-}
-
-
-
-static unsigned int TrackLoads (LoadInfo* LI, LoadInfo* LLI, CodeSeg* S, int I)
-/* Track loads for a code entry.
-** Return used registers.
-*/
-{
- unsigned Used;
- CodeEntry* E = CS_GetEntry (S, I);
- CHECK (E != 0);
-
- /* By default */
- Used = E->Use;
-
- /* Whether we had a load or xfer op before or not, the newly loaded value
- ** will be the real one used for the pushax/op unless it's overwritten,
- ** so we can just reset the flags about it in such cases.
- */
- if (E->Info & OF_LOAD) {
-
- LoadRegInfo* RI = 0;
-
- /* Determine, which register was loaded */
- if (E->Chg & REG_A) {
- RI = &LI->A;
- } else if (E->Chg & REG_X) {
- RI = &LI->X;
- } else if (E->Chg & REG_Y) {
- RI = &LI->Y;
- }
- CHECK (RI != 0);
-
- /* Remember the load */
- RI->LoadIndex = I;
- RI->XferIndex = -1;
-
- /* Set load flags */
- RI->Flags = LI_LOAD_INSN;
- if (E->AM == AM65_IMM) {
- /* These insns are all ok and replaceable */
- RI->Flags |= LI_DIRECT;
- } else if (E->AM == AM65_ZP || E->AM == AM65_ABS) {
- /* These insns are replaceable only if they are not modified later */
- RI->Flags |= LI_CHECK_ARG;
- } else if (E->AM == AM65_ZPY || E->AM == AM65_ABSY) {
- /* These insns are replaceable only if they are not modified later */
- RI->Flags |= LI_CHECK_ARG | LI_CHECK_Y;
- } else if (E->AM == AM65_ZP_INDY &&
- strcmp (E->Arg, "sp") == 0) {
- /* A load from the stack with known offset is also ok, but in this
- ** case we must reload the index register later. Please note that
- ** a load indirect via other zero page locations is not ok, since
- ** these locations may change between the push and the actual
- ** operation.
- */
- RI->Flags |= LI_DIRECT | LI_CHECK_Y | LI_SP;
-
- /* Reg Y can be regarded as unused if this load is removed */
- Used &= ~REG_Y;
- if (RI == &LI->A) {
- LI->Y.Flags |= LI_USED_BY_A;
- } else {
- LI->Y.Flags |= LI_USED_BY_X;
- }
- }
-
- /* If the load offset has a known value, we can just remember and reload
- ** it into the index register later.
- */
- if ((RI->Flags & LI_CHECK_Y) != 0) {
- if (RegValIsKnown (E->RI->In.RegY)) {
- RI->Offs = (unsigned char)E->RI->In.RegY;
- RI->Flags &= ~LI_CHECK_Y;
- RI->Flags |= LI_RELOAD_Y;
- } else {
- /* We need to check if the src of Y is changed */
- RI->LoadYIndex = LI->Y.LoadIndex;
- RI->LoadYEntry = CS_GetEntry (S, RI->LoadYIndex);
- }
- }
-
- /* Watch for any change of the load target */
- if ((RI->Flags & LI_CHECK_ARG) != 0) {
- RI->LoadEntry = CS_GetEntry (S, I);
- }
-
- } else if (E->Info & OF_XFR) {
-
- /* Determine source and target of the transfer and handle the TSX insn */
- LoadRegInfo* Src;
- LoadRegInfo* Tgt;
- switch (E->OPC) {
- case OP65_TAX:
- Src = &LI->A;
- Tgt = &LI->X;
- Used &= ~REG_A;
- Src->Flags |= LI_USED_BY_X;
- break;
- case OP65_TAY:
- Src = &LI->A;
- Tgt = &LI->Y;
- Used &= ~REG_A;
- Src->Flags |= LI_USED_BY_Y;
- break;
- case OP65_TXA:
- Src = &LI->X;
- Tgt = &LI->A;
- Used &= ~REG_X;
- Src->Flags |= LI_USED_BY_A;
- break;
- case OP65_TYA:
- Src = &LI->Y;
- Tgt = &LI->A;
- Used &= ~REG_Y;
- Src->Flags |= LI_USED_BY_A;
- break;
- case OP65_TSX:
- ClearLoadRegInfo (&LI->X);
- return Used;
- case OP65_TXS:
- return Used;
- default: Internal ("Unknown XFR insn in TrackLoads");
- }
-
- /* Transfer the data */
- Tgt->LoadIndex = Src->LoadIndex;
- Tgt->LoadEntry = Src->LoadEntry;
- Tgt->LoadYIndex = Src->LoadYIndex;
- Tgt->LoadYEntry = Src->LoadYEntry;
- Tgt->XferIndex = I;
- Tgt->Offs = Src->Offs;
- Tgt->Flags = Src->Flags;
-
- } else if (CE_IsCallTo (E, "ldaxysp") && RegValIsKnown (E->RI->In.RegY)) {
-
- /* Both registers set, Y changed */
- LI->A.LoadIndex = I;
- LI->A.XferIndex = -1;
- LI->A.Flags = (LI_LOAD_INSN | LI_DIRECT | LI_RELOAD_Y | LI_SP);
- LI->A.Offs = (unsigned char) E->RI->In.RegY - 1;
-
- LI->X.LoadIndex = I;
- LI->X.XferIndex = -1;
- LI->X.Flags = (LI_LOAD_INSN | LI_DIRECT | LI_RELOAD_Y | LI_SP);
- LI->X.Offs = (unsigned char) E->RI->In.RegY;
-
- /* Reg Y can be regarded as unused if this load is removed */
- Used &= ~REG_Y;
- LI->Y.Flags |= LI_USED_BY_A | LI_USED_BY_X;
-
- } else {
- HonourUseAndChg (&LI->A, REG_A, E, I);
- HonourUseAndChg (&LI->X, REG_X, E, I);
- HonourUseAndChg (&LI->Y, REG_Y, E, I);
-
- /* The other operand may be affected too */
- if (LLI != 0) {
- if (Affected (&LLI->A, E)) {
- LLI->A.Flags |= LI_SRC_CHG;
- }
- if (Affected (&LLI->X, E)) {
- LLI->X.Flags |= LI_SRC_CHG;
- }
- if (Affected (&LLI->Y, E)) {
- LLI->Y.Flags |= LI_SRC_CHG;
- }
- }
- }
-
- return Used;
-}
-
/*****************************************************************************/
@@ -570,421 +94,6 @@ static unsigned int TrackLoads (LoadInfo* LI, LoadInfo* LLI, CodeSeg* S, int I)
-static void InsertEntry (StackOpData* D, CodeEntry* E, int Index)
-/* Insert a new entry. Depending on Index, D->PushIndex and D->OpIndex will
-** be adjusted by this function.
-*/
-{
- /* Insert the entry into the code segment */
- CS_InsertEntry (D->Code, E, Index);
-
- /* Adjust register loads if necessary */
- AdjustLoadInfo (&D->Lhs, Index, 1);
- AdjustLoadInfo (&D->Rhs, Index, 1);
-
- /* Adjust the indices if necessary */
- if (D->PushEntry && Index <= D->PushIndex) {
- ++D->PushIndex;
- }
- if (D->OpEntry && Index <= D->OpIndex) {
- ++D->OpIndex;
- }
-}
-
-
-
-static void DelEntry (StackOpData* D, int Index)
-/* Delete an entry. Depending on Index, D->PushIndex and D->OpIndex will be
-** adjusted by this function, and PushEntry/OpEntry may get invalidated.
-*/
-{
- /* Delete the entry from the code segment */
- CS_DelEntry (D->Code, Index);
-
- /* Adjust register loads if necessary */
- AdjustLoadInfo (&D->Lhs, Index, -1);
- AdjustLoadInfo (&D->Rhs, Index, -1);
-
- /* Adjust the other indices if necessary */
- if (Index < D->PushIndex) {
- --D->PushIndex;
- } else if (Index == D->PushIndex) {
- D->PushEntry = 0;
- }
- if (Index < D->OpIndex) {
- --D->OpIndex;
- } else if (Index == D->OpIndex) {
- D->OpEntry = 0;
- }
-}
-
-
-
-static void AdjustStackOffset (StackOpData* D, unsigned Offs)
-/* Adjust the offset for all stack accesses in the range PushIndex to OpIndex.
-** OpIndex is adjusted according to the insertions.
-*/
-{
- /* Walk over all entries */
- int I = D->PushIndex + 1;
- while (I < D->OpIndex) {
-
- CodeEntry* E = CS_GetEntry (D->Code, I);
-
- /* Check if this entry does a stack access, and if so, if it's a plain
- ** load from stack, since this is needed later.
- */
- int Correction = 0;
- if ((E->Use & REG_SP) != 0) {
-
- /* Check for some things that should not happen */
- CHECK (E->AM == AM65_ZP_INDY || E->RI->In.RegY >= (short) Offs);
- CHECK (strcmp (E->Arg, "sp") == 0);
- /* We need to correct this one */
- Correction = (E->OPC == OP65_LDA)? 2 : 1;
-
- } else if (CE_IsCallTo (E, "ldaxysp")) {
- /* We need to correct this one */
- Correction = 1;
- }
-
- if (Correction) {
- /* Get the code entry before this one. If it's a LDY, adjust the
- ** value.
- */
- CodeEntry* P = CS_GetPrevEntry (D->Code, I);
- if (P && P->OPC == OP65_LDY && CE_IsConstImm (P)) {
- /* The Y load is just before the stack access, adjust it */
- CE_SetNumArg (P, P->Num - Offs);
- } else {
- /* Insert a new load instruction before the stack access */
- const char* Arg = MakeHexArg (E->RI->In.RegY - Offs);
- CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
- InsertEntry (D, X, I++);
- }
-
- /* If we need the value of Y later, be sure to reload it */
- if (RegYUsed (D->Code, I+1)) {
- CodeEntry* N;
- const char* Arg = MakeHexArg (E->RI->In.RegY);
- if (Correction == 2 && (N = CS_GetNextEntry(D->Code, I)) != 0 &&
- ((N->Info & OF_ZBRA) != 0) && N->JumpTo != 0) {
- /* The Y register is used but the load instruction loads A
- ** and is followed by a branch that evaluates the zero flag.
- ** This means that we cannot just insert the load insn
- ** for the Y register at this place, because it would
- ** destroy the Z flag. Instead place load insns at the
- ** target of the branch and after it.
- ** Note: There is a chance that this code won't work. The
- ** jump may be a backwards jump (in which case the stack
- ** offset has already been adjusted) or there may be other
- ** instructions between the load and the conditional jump.
- ** Currently the compiler does not generate such code, but
- ** it is possible to force the optimizer into something
- ** invalid by use of inline assembler.
- */
-
- /* Add load insn after the branch */
- CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
- InsertEntry (D, X, I+2);
-
- /* Add load insn before branch target */
- CodeEntry* Y = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
- int J = CS_GetEntryIndex (D->Code, N->JumpTo->Owner);
- CHECK (J > I); /* Must not happen */
- InsertEntry (D, Y, J);
-
- /* Move the label to the new insn */
- CodeLabel* L = CS_GenLabel (D->Code, Y);
- CS_MoveLabelRef (D->Code, N, L);
- } else {
- CodeEntry* X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
- InsertEntry (D, X, I+1);
- /* Skip this instruction in the next round */
- ++I;
- }
- }
- }
-
- /* Next entry */
- ++I;
- }
-
- /* If we have rhs load insns that load from stack, we'll have to adjust
- ** the offsets for these also.
- */
- if ((D->Rhs.A.Flags & (LI_RELOAD_Y | LI_SP | LI_CHECK_Y)) == (LI_RELOAD_Y | LI_SP)) {
- D->Rhs.A.Offs -= Offs;
- }
- if ((D->Rhs.X.Flags & (LI_RELOAD_Y | LI_SP | LI_CHECK_Y)) == (LI_RELOAD_Y | LI_SP)) {
- D->Rhs.X.Offs -= Offs;
- }
-}
-
-
-
-static void AddStoreLhsA (StackOpData* D)
-/* Add a store to zero page after the push insn */
-{
- CodeEntry* X = NewCodeEntry (OP65_STA, AM65_ZP, D->ZPLo, 0, D->PushEntry->LI);
- InsertEntry (D, X, D->PushIndex+1);
-}
-
-
-
-static void AddStoreLhsX (StackOpData* D)
-/* Add a store to zero page after the push insn */
-{
- CodeEntry* X = NewCodeEntry (OP65_STX, AM65_ZP, D->ZPHi, 0, D->PushEntry->LI);
- InsertEntry (D, X, D->PushIndex+1);
-}
-
-
-
-static void ReplacePushByStore (StackOpData* D)
-/* Replace the call to the push subroutine by a store into the zero page
-** location (actually, the push is not replaced, because we need it for
-** later, but the name is still ok since the push will get removed at the
-** end of each routine).
-*/
-{
- /* Store the value into the zeropage instead of pushing it. Check high
- ** byte first so that the store is later in A/X order.
- */
- if ((D->Lhs.X.Flags & LI_DIRECT) == 0) {
- AddStoreLhsX (D);
- }
- if ((D->Lhs.A.Flags & LI_DIRECT) == 0) {
- AddStoreLhsA (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 {
-
- if ((LI->A.Flags & LI_CHECK_Y) == 0) {
- /* ldy #offs */
- X = NewCodeEntry (OP65_LDY, AM65_IMM, MakeHexArg (LI->A.Offs), 0, D->OpEntry->LI);
- } else {
- /* ldy src */
- X = NewCodeEntry (OP65_LDY, LI->A.LoadYEntry->AM, LI->A.LoadYEntry->Arg, 0, D->OpEntry->LI);
- }
- InsertEntry (D, X, D->IP++);
-
- if (LI->A.LoadEntry->OPC == OP65_JSR) {
- /* opc (sp),y */
- X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
- } else {
- /* opc src,y */
- X = NewCodeEntry (OPC, LI->A.LoadEntry->AM, LI->A.LoadEntry->Arg, 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 {
-
- if ((LI->A.Flags & LI_CHECK_Y) == 0) {
- /* ldy #const */
- X = NewCodeEntry (OP65_LDY, AM65_IMM, MakeHexArg (LI->X.Offs), 0, D->OpEntry->LI);
- } else {
- /* ldy src */
- X = NewCodeEntry (OP65_LDY, LI->X.LoadYEntry->AM, LI->X.LoadYEntry->Arg, 0, D->OpEntry->LI);
- }
- InsertEntry (D, X, D->IP++);
-
- if (LI->X.LoadEntry->OPC == OP65_JSR) {
- /* opc (sp),y */
- X = NewCodeEntry (OPC, AM65_ZP_INDY, "sp", 0, D->OpEntry->LI);
- } else {
- /* opc src,y */
- X = NewCodeEntry (OPC, LI->A.LoadEntry->AM, LI->A.LoadEntry->Arg, 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_REMOVE) {
- if (LI->A.LoadIndex >= 0 &&
- (LI->A.LoadEntry->Flags & CEF_DONT_REMOVE) == 0) {
- DelEntry (D, LI->A.LoadIndex);
- }
- if (LI->A.XferIndex >= 0 &&
- (LI->A.XferEntry->Flags & CEF_DONT_REMOVE) == 0) {
- DelEntry (D, LI->A.XferIndex);
- }
- }
- if ((LI->X.Flags & LI_REMOVE) == LI_REMOVE) {
- if (LI->X.LoadIndex >= 0 &&
- (LI->X.LoadEntry->Flags & CEF_DONT_REMOVE) == 0) {
- DelEntry (D, LI->X.LoadIndex);
- }
- if (LI->X.XferIndex >= 0 &&
- (LI->X.XferEntry->Flags & CEF_DONT_REMOVE) == 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 if nothing prevents that */
- 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 that is unchanged until Op,
-** 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 be unchanged till Op */
- if ((D->Lhs.A.Flags & (LI_DIRECT | LI_RELOAD_Y)) != LI_DIRECT ||
- (D->Lhs.X.Flags & (LI_DIRECT | LI_RELOAD_Y)) != LI_DIRECT) {
- return 0;
- }
-
- /* 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;
-}
-
-
-
-static RegInfo* GetLastChangedRegInfo (StackOpData* D, LoadRegInfo* Reg)
-/* Get RegInfo of the last load insn entry */
-{
- CodeEntry* E;
-
- if (Reg->LoadIndex >= 0 && (E = CS_GetEntry (D->Code, Reg->LoadIndex)) != 0) {
- return E->RI;
- }
-
- return 0;
-}
-
-
-
static int SameRegAValue (StackOpData* D)
/* Check if Rhs Reg A == Lhs Reg A */
{
@@ -2304,94 +1413,6 @@ static const OptFuncDesc* FindFunc (const OptFuncDesc FuncTable[], size_t Count,
-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",
- "bcastax",
- "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->ZPUsage = REG_NONE;
- Data->ZPChanged = REG_NONE;
- Data->UsedRegs = REG_NONE;
- Data->RhsMultiChg = 0;
-
- 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
@@ -2701,52 +1722,6 @@ static int RegAPreCondOk (StackOpData* D)
-static void SetDontRemoveEntryFlag (LoadRegInfo* RI)
-/* Flag the entry as non-removable according to register flags */
-{
- if (RI->Flags & LI_DONT_REMOVE) {
- if (RI->LoadEntry != 0) {
- RI->LoadEntry->Flags |= CEF_DONT_REMOVE;
- }
- }
-}
-
-
-
-static void ResetDontRemoveEntryFlag (LoadRegInfo* RI)
-/* Unflag the entry as non-removable according to register flags */
-{
- if (RI->Flags & LI_DONT_REMOVE) {
- if (RI->LoadEntry != 0) {
- RI->LoadEntry->Flags &= ~CEF_DONT_REMOVE;
- }
- }
-}
-
-
-
-static void SetDontRemoveEntryFlags (StackOpData* D)
-/* Flag the entries as non-removable according to register flags */
-{
- SetDontRemoveEntryFlag (&D->Lhs.A);
- SetDontRemoveEntryFlag (&D->Lhs.X);
- SetDontRemoveEntryFlag (&D->Rhs.A);
- SetDontRemoveEntryFlag (&D->Rhs.X);
-}
-
-
-
-static void ResetDontRemoveEntryFlags (StackOpData* D)
-/* Unflag the entries as non-removable according to register flags */
-{
- ResetDontRemoveEntryFlag (&D->Lhs.A);
- ResetDontRemoveEntryFlag (&D->Lhs.X);
- ResetDontRemoveEntryFlag (&D->Rhs.A);
- ResetDontRemoveEntryFlag (&D->Rhs.X);
-}
-
-
-
unsigned OptStackOps (CodeSeg* S)
/* Optimize operations that take operands via the stack */
{