(E->Chg & REG_Y)? 'Y' : '_');
// }
- /* Terminate the line */
- fprintf (F, "\n");
}
AddCodeLine ("lda %s", lbuf); /* load A from the label */
if (!(flags & CF_UNSIGNED)) {
/* Must sign extend */
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel ();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* X is invalid now */
+ g_defcodelabel (L);
}
}
break;
AddCodeLine ("lda (sp),y");
}
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* X is invalid now */
+ g_defcodelabel (L);
}
}
break;
ldaconst (offs); /* Load A with offset value */
AddCodeLine ("jsr leaasp"); /* Load effective address */
} else {
+ unsigned L = GetLocalLabel ();
if (CPU == CPU_65C02 && offs == 1) {
AddCodeLine ("lda sp");
AddCodeLine ("ldx sp+1");
AddCodeLine ("ina");
- AddCodeLine ("bne *+3");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!"); /* Invalidate X */
} else {
ldaconst (offs);
AddCodeLine ("clc");
AddCodeLine ("ldx sp+1");
AddCodeLine ("adc sp");
- AddCodeLine ("bcc *+3");
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!"); /* Invalidate X */
}
+ g_defcodelabel (L);
}
}
}
/* Add the value of the stackpointer */
if (CodeSizeFactor > 250) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("ldx sp+1");
AddCodeLine ("clc");
AddCodeLine ("adc sp");
- AddCodeLine ("bcc *+3");
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!"); /* Invalidate X */
+ g_defcodelabel (L);
} else {
AddCodeLine ("jsr leaasp");
}
void g_addlocal (unsigned flags, int offs)
/* Add a local variable to ax */
{
+ unsigned L;
+
/* Correct the offset and check it */
offs -= oursp;
CheckLocalOffs (offs);
switch (flags & CF_TYPE) {
case CF_CHAR:
+ L = GetLocalLabel();
AddCodeLine ("ldy #$%02X", offs & 0xFF);
AddCodeLine ("clc");
AddCodeLine ("adc (sp),y");
- AddCodeLine ("bcc *+3");
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!");
+ g_defcodelabel (L);
break;
case CF_INT:
void g_addstatic (unsigned flags, unsigned long label, unsigned offs)
/* Add a static variable to ax */
{
+ unsigned L;
+
/* Create the correct label name */
char* lbuf = GetLabelName (flags, label, offs);
switch (flags & CF_TYPE) {
case CF_CHAR:
+ L = GetLocalLabel();
AddCodeLine ("clc");
AddCodeLine ("adc %s", lbuf);
- AddCodeLine ("bcc *+3");
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!");
+ g_defcodelabel (L);
break;
case CF_INT:
AddCodeLine ("sta %s", lbuf);
}
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* Invalidate X */
+ g_defcodelabel (L);
}
break;
}
}
}
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* Invalidate X */
+ g_defcodelabel (L);
}
break;
}
AddCodeLine ("sta %s", lbuf);
}
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* Invalidate X */
+ g_defcodelabel (L);
}
break;
}
}
AddCodeLine ("sta (sp),y");
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dex");
- AddCodeHint ("x:!"); /* Invalidate X */
+ g_defcodelabel (L);
}
break;
}
void g_addaddr_local (unsigned flags, int offs)
/* Add the address of a local variable to ax */
{
+ unsigned L = 0;
+
/* Add the offset */
offs -= oursp;
if (offs != 0) {
/* We cannot address more then 256 bytes of locals anyway */
+ L = GetLocalLabel();
CheckLocalOffs (offs);
AddCodeLine ("clc");
AddCodeLine ("adc #$%02X", offs & 0xFF);
- AddCodeLine ("bcc *+4"); /* Do also skip the CLC insn below */
+ /* Do also skip the CLC insn below */
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- AddCodeHint ("x:!"); /* Invalidate X */
}
/* Add the current stackpointer value */
AddCodeLine ("clc");
+ if (L != 0) {
+ /* Label was used above */
+ g_defcodelabel (L);
+ }
AddCodeLine ("adc sp");
AddCodeLine ("tay");
AddCodeLine ("txa");
* will be set.
*/
{
+ unsigned L;
+
/* Check the size and determine operation */
switch (flags & CF_TYPE) {
case CF_CHAR:
if (flags & CF_FORCECHAR) {
AddCodeLine ("cmp #$%02X", (unsigned char)val);
- break;
+ break;
}
/* FALLTHROUGH */
case CF_INT:
+ L = GetLocalLabel();
AddCodeLine ("cmp #$%02X", (unsigned char)val);
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
+ g_defcodelabel (L);
break;
case CF_LONG:
AddCodeLine ("ldy #$00");
AddCodeLine ("ldx sreg+1");
if ((flags & CF_UNSIGNED) == 0) {
- AddCodeLine ("bpl *+3");
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("bpl %s", LocalLabelName (L));
AddCodeLine ("dey");
- AddCodeHint ("y:!");
+ g_defcodelabel (L);
}
AddCodeLine ("lda sreg");
AddCodeLine ("sty sreg+1");
case CF_INT:
if (CPU == CPU_65C02 && val == 1) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("ina");
- AddCodeLine ("bne *+3");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("inx");
- /* Tell the optimizer that the X register may be invalid */
- AddCodeHint ("x:!");
+ g_defcodelabel (L);
} else if (CodeSizeFactor < 200) {
/* Use jsr calls */
if (val <= 8) {
/* Inline the code */
if (val < 0x300) {
if ((val & 0xFF) != 0) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("clc");
AddCodeLine ("adc #$%02X", (unsigned char) val);
- AddCodeLine ("bcc *+3");
+ AddCodeLine ("bcc %s", LocalLabelName (L));
AddCodeLine ("inx");
- /* Tell the optimizer that the X register may be invalid */
- AddCodeHint ("x:!");
+ g_defcodelabel (L);
}
if (val >= 0x100) {
AddCodeLine ("inx");
/* Inline the code */
if (val < 0x300) {
if ((val & 0xFF) != 0) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("sec");
AddCodeLine ("sbc #$%02X", (unsigned char) val);
- AddCodeLine ("bcs *+3");
+ AddCodeLine ("bcs %s", LocalLabelName (L));
AddCodeLine ("dex");
- /* Tell the optimizer that the X register may be invalid */
- AddCodeHint ("x:!");
+ g_defcodelabel (L);
}
if (val >= 0x100) {
AddCodeLine ("dex");
static char* ops [12] = {
"toseq00", "toseqa0", "toseqax",
"toseq00", "toseqa0", "toseqax",
- 0, 0, "toseqeax",
- 0, 0, "toseqeax",
+ 0, 0, "toseqeax",
+ 0, 0, "toseqeax",
};
+ unsigned L;
+
/* If the right hand side is const, the lhs is not on stack but still
* in the primary register.
*/
/* FALLTHROUGH */
case CF_INT:
+ L = GetLocalLabel();
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr booleq");
return;
0, 0, "tosneeax",
};
+ unsigned L;
/* If the right hand side is const, the lhs is not on stack but still
* in the primary register.
/* FALLTHROUGH */
case CF_INT:
+ L = GetLocalLabel();
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr boolne");
return;
/* Test for less than */
{
static char* ops [12] = {
- "toslt00", "toslta0", "tosltax",
- "tosult00", "tosulta0", "tosultax",
- 0, 0, "toslteax",
- 0, 0, "tosulteax",
+ "toslt00", "toslta0", "tosltax",
+ "tosult00", "tosulta0", "tosultax",
+ 0, 0, "toslteax",
+ 0, 0, "tosulteax",
};
/* If the right hand side is const, the lhs is not on stack but still
switch (flags & CF_TYPE) {
case CF_CHAR:
- if (flags & CF_FORCECHAR) {
- AddCodeLine ("cmp #$%02X", (unsigned char)val);
- if (flags & CF_UNSIGNED) {
- AddCodeLine ("jsr boolult");
- } else {
- AddCodeLine ("jsr boollt");
- }
- return;
- }
- /* FALLTHROUGH */
+ if (flags & CF_FORCECHAR) {
+ AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ if (flags & CF_UNSIGNED) {
+ AddCodeLine ("jsr boolult");
+ } else {
+ AddCodeLine ("jsr boollt");
+ }
+ return;
+ }
+ /* FALLTHROUGH */
case CF_INT:
- if ((flags & CF_UNSIGNED) == 0 && val == 0) {
- /* If we have a signed compare against zero, we only need to
- * test the high byte.
- */
- AddCodeLine ("txa");
- AddCodeLine ("jsr boollt");
- return;
- }
- /* Direct code only for unsigned data types */
- if (flags & CF_UNSIGNED) {
- AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
- AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ if ((flags & CF_UNSIGNED) == 0 && val == 0) {
+ /* If we have a signed compare against zero, we only need to
+ * test the high byte.
+ */
+ AddCodeLine ("txa");
+ AddCodeLine ("jsr boollt");
+ return;
+ }
+ /* Direct code only for unsigned data types */
+ if (flags & CF_UNSIGNED) {
+ unsigned L = GetLocalLabel();
+ AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
+ AddCodeLine ("bne %s", LocalLabelName (L));
+ AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr boolult");
return;
}
/* If we go here, we didn't emit code. Push the lhs on stack and fall
* into the normal, non-optimized stuff.
*/
- g_push (flags & ~CF_CONST, 0);
+ g_push (flags & ~CF_CONST, 0);
}
case CF_INT:
if (flags & CF_UNSIGNED) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr boolule");
return;
}
AddCodeLine ("ora tmp1");
AddCodeLine ("jsr boolne");
} else {
+ unsigned L = GetLocalLabel();
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr boolugt");
}
return;
}
/* Direct code only for unsigned data types */
if (flags & CF_UNSIGNED) {
+ unsigned L = GetLocalLabel();
AddCodeLine ("cpx #$%02X", (unsigned char)(val >> 8));
- AddCodeLine ("bne *+4");
+ AddCodeLine ("bne %s", LocalLabelName (L));
AddCodeLine ("cmp #$%02X", (unsigned char)val);
+ g_defcodelabel (L);
AddCodeLine ("jsr booluge");
return;
}
#include "coll.h"
/* cc65 */
+#include "codeent.h"
+#include "codeseg.h"
+#include "error.h"
#include "codeinfo.h"
};
static const FuncInfo FuncInfoTable[] = {
- { "booleq", REG_NONE, REG_AX },
- { "boolge", REG_NONE, REG_AX },
- { "boolgt", REG_NONE, REG_AX },
- { "boolle", REG_NONE, REG_AX },
- { "boollt", REG_NONE, REG_AX },
- { "boolne", REG_NONE, REG_AX },
- { "booluge", REG_NONE, REG_AX },
- { "boolugt", REG_NONE, REG_AX },
- { "boolule", REG_NONE, REG_AX },
- { "boolult", REG_NONE, REG_AX },
- { "decax1", REG_AX, REG_AX },
- { "decax2", REG_AX, REG_AX },
- { "decax3", REG_AX, REG_AX },
- { "decax4", REG_AX, REG_AX },
- { "decax5", REG_AX, REG_AX },
- { "decax6", REG_AX, REG_AX },
- { "decax7", REG_AX, REG_AX },
- { "decax8", REG_AX, REG_AX },
- { "decaxy", REG_AXY, REG_AX },
- { "decsp2", REG_NONE, REG_A },
- { "decsp3", REG_NONE, REG_A },
- { "decsp4", REG_NONE, REG_A },
- { "decsp5", REG_NONE, REG_A },
- { "decsp6", REG_NONE, REG_A },
- { "decsp7", REG_NONE, REG_A },
- { "decsp8", REG_NONE, REG_A },
- { "ldax0sp", REG_Y, REG_AX },
- { "ldaxysp", REG_Y, REG_AX },
- { "pusha", REG_A, REG_Y },
- { "pusha0", REG_A, REG_XY },
- { "pushax", REG_AX, REG_Y },
- { "pushw0sp", REG_NONE, REG_AXY },
- { "pushwysp", REG_Y, REG_AXY },
- { "tosicmp", REG_AX, REG_AXY },
+ { "addysp", REG_Y, REG_NONE },
+ { "booleq", REG_NONE, REG_AX },
+ { "boolge", REG_NONE, REG_AX },
+ { "boolgt", REG_NONE, REG_AX },
+ { "boolle", REG_NONE, REG_AX },
+ { "boollt", REG_NONE, REG_AX },
+ { "boolne", REG_NONE, REG_AX },
+ { "booluge", REG_NONE, REG_AX },
+ { "boolugt", REG_NONE, REG_AX },
+ { "boolule", REG_NONE, REG_AX },
+ { "boolult", REG_NONE, REG_AX },
+ { "decax1", REG_AX, REG_AX },
+ { "decax2", REG_AX, REG_AX },
+ { "decax3", REG_AX, REG_AX },
+ { "decax4", REG_AX, REG_AX },
+ { "decax5", REG_AX, REG_AX },
+ { "decax6", REG_AX, REG_AX },
+ { "decax7", REG_AX, REG_AX },
+ { "decax8", REG_AX, REG_AX },
+ { "decaxy", REG_AXY, REG_AX },
+ { "decsp2", REG_NONE, REG_A },
+ { "decsp3", REG_NONE, REG_A },
+ { "decsp4", REG_NONE, REG_A },
+ { "decsp5", REG_NONE, REG_A },
+ { "decsp6", REG_NONE, REG_A },
+ { "decsp7", REG_NONE, REG_A },
+ { "decsp8", REG_NONE, REG_A },
+ { "incsp1", REG_NONE, REG_NONE },
+ { "incsp2", REG_NONE, REG_Y },
+ { "incsp3", REG_NONE, REG_Y },
+ { "incsp4", REG_NONE, REG_Y },
+ { "incsp5", REG_NONE, REG_Y },
+ { "incsp6", REG_NONE, REG_Y },
+ { "incsp7", REG_NONE, REG_Y },
+ { "incsp8", REG_NONE, REG_Y },
+ { "ldax0sp", REG_Y, REG_AX },
+ { "ldaxysp", REG_Y, REG_AX },
+ { "pusha", REG_A, REG_Y },
+ { "pusha0", REG_A, REG_XY },
+ { "pushax", REG_AX, REG_Y },
+ { "pushw0sp", REG_NONE, REG_AXY },
+ { "pushwysp", REG_Y, REG_AXY },
+ { "tosicmp", REG_AX, REG_AXY },
};
#define FuncInfoCount (sizeof(FuncInfoTable) / sizeof(FuncInfoTable[0]))
-/* Structure used to pass information to the RegValUsedInt1 and 2 functions */
-typedef struct RVUInfo RVUInfo;
-struct RVUInfo {
- Collection VisitedLines; /* Lines already visited */
-};
-
/*****************************************************************************/
*Use |= Info->Use;
*Chg |= Info->Chg;
} else {
+ /* Assume all registers used */
*Use |= REG_AXY;
*Chg |= REG_AXY;
}
}
-
-#if 0
-static unsigned RVUInt2 (Line* L,
- LineColl* LC, /* To remember visited lines */
- unsigned Used, /* Definitely used registers */
- unsigned Unused) /* Definitely unused registers */
-/* Subfunction for RegValUsed. Will be called recursively in case of branches. */
-{
- int I;
- /* Check the following instructions. We classifiy them into primary
- * loads (register value not used), neutral (check next instruction),
- * and unknown (assume register was used).
- */
+static unsigned char GetRegInfo2 (CodeSeg* S,
+ CodeEntry* E,
+ int Index,
+ Collection* Visited,
+ unsigned char Used,
+ unsigned char Unused)
+/* Recursively called subfunction for GetRegInfo. */
+{
+ /* Follow the instruction flow recording register usage. */
while (1) {
- unsigned R;
-
- /* Get the next line and follow jumps */
- do {
-
- /* Handle jumps to local labels (continue there) */
- if (LineMatch (L, "\tjmp\tL") || LineMatch (L, "\tbra\tL")) {
- /* Get the target of the jump */
- L = GetTargetLine (L->Line+5);
- }
-
- /* Get the next line, skip local labels */
- do {
- L = NextCodeSegLine (L);
- } while (L && (IsLocalLabel (L) || L->Line[0] == '\0'));
-
- /* Bail out if we're done */
- if (L == 0 || IsExtLabel (L)) {
- /* End of function reached */
- goto ExitPoint;
- }
-
- /* Check if we had this line already. If so, bail out, if not,
- * add it to the list of known lines.
- */
- if (LCHasLine (LC, L) || !LCAddLine (LC, L)) {
- goto ExitPoint;
- }
-
- } while (LineMatch (L, "\tjmp\tL") || LineMatch (L, "\tbra\tL"));
-
- /* Special handling of code hints */
- if (IsHintLine (L)) {
-
- if (IsHint (L, "a:-") && (Used & REG_A) == 0) {
- Unused |= REG_A;
- } else if (IsHint (L, "x:-") && (Used & REG_X) == 0) {
- Unused |= REG_X;
- } else if (IsHint (L, "y:-") && (Used & REG_Y) == 0) {
- Unused |= REG_Y;
- }
-
- /* Special handling for branches */
- } else if (LineMatchX (L, ShortBranches) >= 0 ||
- LineMatchX (L, LongBranches) >= 0) {
- const char* Target = L->Line+5;
- if (Target[0] == 'L') {
- /* Jump to local label. Check the register usage starting at
- * the branch target and at the code following the branch.
- * All registers that are unused in both execution flows are
- * returned as unused.
- */
- unsigned U1, U2;
- U2 = RVUInt1 (GetTargetLine (Target), LC, Used, Unused);
- U1 = RVUInt1 (L, LC, Used, Unused);
- return U1 | U2; /* Used in any of the branches */
- }
- } else {
-
- /* Search for the instruction in this line */
- I = FindCmd (L);
-
- /* If we don't find it, assume all other registers are used */
- if (I < 0) {
- break;
- }
-
- /* Evaluate the use flags, check for addressing modes */
- R = CmdDesc[I].Use;
- if (IsXAddrMode (L)) {
- R |= REG_X;
- } else if (IsYAddrMode (L)) {
- R |= REG_Y;
- }
- if (R) {
- /* Remove registers that were already new loaded */
- R &= ~Unused;
-
- /* Remember the remaining registers */
- Used |= R;
- }
-
- /* Evaluate the load flags */
- R = CmdDesc[I].Load;
- if (R) {
- /* Remove registers that were already used */
- R &= ~Used;
-
- /* Remember the remaining registers */
- Unused |= R;
- }
-
- }
-
- /* If we know about all registers, bail out */
- if ((Used | Unused) == REG_ALL) {
+ unsigned char R;
+
+ /* Check if we have already visited the current code entry. If so,
+ * bail out.
+ */
+ if (CodeEntryHasMark (E)) {
+ break;
+ }
+
+ /* Mark this entry as already visited */
+ CodeEntrySetMark (E);
+ CollAppend (Visited, E);
+
+ /* Evaluate the used registers */
+ if ((R = E->Use) != REG_NONE) {
+ /* We are not interested in the use of any register that has been
+ * used before.
+ */
+ R &= ~Unused;
+ /* Remember the remaining registers */
+ Used |= R;
+ }
+
+ /* Evaluate the changed registers */
+ if ((R = E->Chg) != REG_NONE) {
+ /* We are not interested in the use of any register that has been
+ * used before.
+ */
+ R &= ~Used;
+ /* Remember the remaining registers */
+ Unused |= R;
+ }
+
+ /* If we know about all registers now, bail out */
+ if ((Used | Unused) == REG_AXY) {
break;
}
+
+ /* If the instruction is an RTS or RTI, we're done */
+ if (E->OPC == OPC_RTS || E->OPC == OPC_RTI) {
+ break;
+ }
+
+ /* If we have an unconditional branch, follow this branch if possible,
+ * otherwise we're done.
+ */
+ if ((E->Info & OF_UBRA) != 0) {
+
+ /* Does this jump have a valid target? */
+ if (E->JumpTo) {
+
+ /* Unconditional jump */
+ E = E->JumpTo->Owner;
+ Index = -1; /* Invalidate */
+
+ } else {
+ /* Jump outside means we're done */
+ break;
+ }
+
+ /* In case of conditional branches, follow the branch if possible and
+ * follow the normal flow (branch not taken) afterwards. If we cannot
+ * follow the branch, we're done.
+ */
+ } else if ((E->Info & OF_CBRA) != 0) {
+
+ if (E->JumpTo) {
+
+ /* Recursively determine register usage at the branch target */
+ unsigned char U1;
+ unsigned char U2;
+
+ U1 = GetRegInfo2 (S, E->JumpTo->Owner, -1, Visited, Used, Unused);
+ if (U1 == REG_AXY) {
+ /* All registers used, no need for second call */
+ return REG_AXY;
+ }
+ if (Index < 0) {
+ Index = GetCodeEntryIndex (S, E);
+ }
+ if ((E = GetCodeEntry (S, ++Index)) == 0) {
+ Internal ("GetRegInfo2: No next entry!");
+ }
+ U2 = GetRegInfo2 (S, E, Index, Visited, Used, Unused);
+ return U1 | U2; /* Used in any of the branches */
+
+ } else {
+ /* Jump to global symbol */
+ break;
+ }
+
+ } else {
+
+ /* Just go to the next instruction */
+ if (Index < 0) {
+ Index = GetCodeEntryIndex (S, E);
+ }
+ E = GetCodeEntry (S, ++Index);
+ if (E == 0) {
+ /* No next entry */
+ Internal ("GetRegInfo2: No next entry!");
+ }
+
+ }
+
}
-ExitPoint:
/* Return to the caller the complement of all unused registers */
- return ~Unused & REG_ALL;
+ return Used;
}
-static unsigned RVUInt1 (Line* L,
- LineColl* LC, /* To remember visited lines */
- unsigned Used, /* Definitely used registers */
- unsigned Unused) /* Definitely unused registers */
-/* Subfunction for RegValUsed. Will be called recursively in case of branches. */
+static unsigned char GetRegInfo1 (CodeSeg* S,
+ CodeEntry* E,
+ int Index,
+ Collection* Visited,
+ unsigned char Used,
+ unsigned char Unused)
+/* Recursively called subfunction for GetRegInfo. */
{
/* Remember the current count of the line collection */
- unsigned Count = LC->Count;
+ unsigned Count = CollCount (Visited);
/* Call the worker routine */
- unsigned R = RVUInt2 (L, LC, Used, Unused);
-
- /* Restore the old count */
- LC->Count = Count;
+ unsigned char R = GetRegInfo2 (S, E, Index, Visited, Used, Unused);
+
+ /* Restore the old count, unmarking all new entries */
+ unsigned NewCount = CollCount (Visited);
+ while (NewCount-- > Count) {
+ CodeEntry* E = CollAt (Visited, NewCount);
+ CodeEntryResetMark (E);
+ CollDelete (Visited, NewCount);
+ }
- /* Return the result */
+ /* Return the registers used */
return R;
}
-static unsigned RegValUsed (Line* Start)
-/* Check the next instructions after the one in L for register usage. If
- * a register is used as an index, or in a store or other instruction, it
- * is assumed to be used. If a register is loaded with a value, before it
- * was used by one of the actions described above, it is assumed unused.
- * If the end of the lookahead is reached, all registers that are uncertain
- * are marked as used.
- * The result of the search is returned.
+unsigned char GetRegInfo (struct CodeSeg* S, unsigned Index)
+/* Determine register usage information for the instructions starting at the
+ * given index.
*/
{
- unsigned R;
+ CodeEntry* E;
+ Collection Visited; /* Visited entries */
+ unsigned char R;
+
+ /* Get the code entry for the given index */
+ if (Index >= GetCodeEntryCount (S)) {
+ /* There is no such code entry */
+ return REG_NONE;
+ }
+ E = GetCodeEntry (S, Index);
- /* Create a new line collection and enter the start line */
- LineColl* LC = NewLineColl (256);
- LCAddLine (LC, Start);
+ /* Initialize the data structure used to collection information */
+ InitCollection (&Visited);
/* Call the recursive subfunction */
- R = RVUInt1 (Start, LC, REG_NONE, REG_NONE);
+ R = GetRegInfo1 (S, E, Index, &Visited, REG_NONE, REG_NONE);
/* Delete the line collection */
- FreeLineColl (LC);
+ DoneCollection (&Visited);
/* Return the registers used */
return R;
-static int RegAUsed (Line* Start)
+int RegAUsed (struct CodeSeg* S, unsigned Index)
/* Check if the value in A is used. */
{
- return (RegValUsed (Start) & REG_A) != 0;
+ return (GetRegInfo (S, Index) & REG_A) != 0;
}
-static int RegXUsed (Line* Start)
+int RegXUsed (struct CodeSeg* S, unsigned Index)
/* Check if the value in X is used. */
{
- return (RegValUsed (Start) & REG_X) != 0;
+ return (GetRegInfo (S, Index) & REG_X) != 0;
}
-static int RegYUsed (Line* Start)
+int RegYUsed (struct CodeSeg* S, unsigned Index)
/* Check if the value in Y is used. */
{
- return (RegValUsed (Start) & REG_Y) != 0;
+ return (GetRegInfo (S, Index) & REG_Y) != 0;
}
-#endif
+/*****************************************************************************/
+/* Forwards */
+/*****************************************************************************/
+
+
+
+struct CodeSeg;
+
+
+
/*****************************************************************************/
/* Data */
/*****************************************************************************/
* will use all registers and load all registers.
*/
+unsigned char GetRegInfo (struct CodeSeg* S, unsigned Index);
+/* Determine register usage information for the instructions starting at the
+ * given index.
+ */
+
+int RegAUsed (struct CodeSeg* S, unsigned Index);
+/* Check if the value in A is used. */
+
+int RegXUsed (struct CodeSeg* S, unsigned Index);
+/* Check if the value in X is used. */
+
+int RegYUsed (struct CodeSeg* S, unsigned Index);
+/* Check if the value in Y is used. */
+
/* End of codeinfo.h */
{ OptDeadCode, "OptDeadCode", 0 },
/* Optimize jump targets */
{ OptJumpTarget, "OptJumpTarget", 0 },
- /* Remove dead conditional branches */
- { OptDeadCondBranches, "OptDeadCondBranches", 0 },
+ /* Optimize conditional branches */
+ { OptCondBranches, "OptCondBranches", 0 },
/* Remove calls to the bool transformer subroutines */
{ OptBoolTransforms, "OptBoolTransforms", 0 },
+ /* Remove unused loads */
+ { OptUnusedLoads, "OptUnusedLoads", 0 },
};
unsigned Pass = 0;
unsigned OptChanges;
+ /* If we shouldn't run the optimizer, bail out */
+ if (!Optimize) {
+ return;
+ }
+
/* Print the name of the function we are working on */
if (S->Func) {
Print (stdout, 1, "Running optimizer for function `%s'\n", S->Func->Name);
+void InsertCodeEntry (CodeSeg* S, struct CodeEntry* E, unsigned Index)
+/* Insert the code entry at the index given. Following code entries will be
+ * moved to slots with higher indices.
+ */
+{
+ /* Insert the entry into the collection */
+ CollInsert (&S->Entries, E, Index);
+}
+
+
+
void DelCodeEntry (CodeSeg* S, unsigned Index)
/* Delete an entry from the code segment. This includes moving any associated
* labels, removing references to labels and even removing the referenced labels
+struct CodeEntry* GetNextCodeEntry (CodeSeg* S, unsigned Index)
+/* Get the code entry following the one with the index Index. If there is no
+ * following code entry, return NULL.
+ */
+{
+ if (Index >= CollCount (&S->Entries)-1) {
+ /* This is the last entry */
+ return 0;
+ } else {
+ /* Code entries left */
+ return CollAt (&S->Entries, Index+1);
+ }
+}
+
+
+
unsigned GetCodeEntryIndex (CodeSeg* S, struct CodeEntry* E)
/* Return the index of a code entry */
{
* errors to slip through.
*/
if (L->Owner) {
- CollDeleteItem (&L->Owner->Labels, L);
+ CollDeleteItem (&L->Owner->Labels, L);
}
/* All references removed, delete the label itself */
/* If there are no more references, delete the label */
if (CollCount (&L->JumpFrom) == 0) {
- DelCodeLabel (S, L);
+ DelCodeLabel (S, L);
}
}
/* Get the number of entries in this segment */
unsigned Count = GetCodeEntryCount (S);
- /* Check if we have to delete anything */
- if (Last < Count) {
+ /* First pass: Delete all references to labels. If the reference count
+ * for a label drops to zero, delete it.
+ */
+ unsigned C = Count;
+ while (Last < C--) {
+
+ /* Get the next entry */
+ CodeEntry* E = GetCodeEntry (S, C);
- /* Remove all entries after the given one */
- while (Last < Count--) {
+ /* Check if this entry has a label reference */
+ if (E->JumpTo) {
+ /* Remove the reference to the label */
+ RemoveCodeLabelRef (S, E);
+ }
- /* Get the next entry */
- CodeEntry* E = GetCodeEntry (S, Count);
+ }
- /* If the code entry has labels, delete them */
- while (CodeEntryHasLabel (E)) {
+ /* Second pass: Delete the instructions. If a label attached to an
+ * instruction still has references, it must be references from outside
+ * the deleted area. Don't delete the label in this case, just make it
+ * ownerless and move it to the label pool.
+ */
+ C = Count;
+ while (Last < C--) {
- /* Get the label */
- CodeLabel* L = GetCodeLabel (E, 0);
+ /* Get the next entry */
+ CodeEntry* E = GetCodeEntry (S, C);
- /* Delete it */
- DelCodeLabel (S, L);
+ /* Check if this entry has a label attached */
+ if (CodeEntryHasLabel (E)) {
+ /* Move the labels to the pool and clear the owner pointer */
+ MoveLabelsToPool (S, E);
+ }
- }
+ /* Delete the pointer to the entry */
+ CollDelete (&S->Entries, C);
- /* Delete the entry itself */
- DelCodeEntry (S, Count);
- }
+ /* Delete the entry itself */
+ FreeCodeEntry (E);
}
}
/* Output all entries */
for (I = 0; I < Count; ++I) {
+
+ unsigned char Use;
+
OutputCodeEntry (CollConstAt (&S->Entries, I), F);
+
+ /* Print usage info */
+ Use = GetRegInfo ((CodeSeg*) S, I+1);
+ fprintf (F,
+ " Use: %c%c%c\n",
+ (Use & REG_A)? 'A' : '_',
+ (Use & REG_X)? 'X' : '_',
+ (Use & REG_Y)? 'Y' : '_');
}
/* If this is a segment for a function, leave the function */
void AddCodeEntry (CodeSeg* S, const char* Format, va_list ap) attribute ((format(printf,2,0)));
/* Add a line to the given code segment */
+void InsertCodeEntry (CodeSeg* S, struct CodeEntry* E, unsigned Index);
+/* Insert the code entry at the index given. Following code entries will be
+ * moved to slots with higher indices.
+ */
+
void DelCodeEntry (CodeSeg* S, unsigned Index);
/* Delete an entry from the code segment. This includes moving any associated
* labels, removing references to labels and even removing the referenced labels
struct CodeEntry* GetCodeEntry (CodeSeg* S, unsigned Index);
/* Get an entry from the given code segment */
+struct CodeEntry* GetNextCodeEntry (CodeSeg* S, unsigned Index);
+/* Get the code entry following the one with the index Index. If there is no
+ * following code entry, return NULL.
+ */
+
unsigned GetCodeEntryIndex (CodeSeg* S, struct CodeEntry* E);
/* Return the index of a code entry */
* the second branch will never be taken, and we may jump directly
* to the instruction behind this one.
*/
- goto NextEntry;
+ if ((E->Info & OF_CBRA) != 0 && (N->Info & OF_CBRA) != 0) {
+ unsigned NI; /* Index of N */
+ CodeEntry* X; /* Instruction behind N */
+ CodeLabel* LX; /* Label attached to X */
+
+ /* Get the branch conditions of both branches */
+ bc_t BC1 = GetBranchCond (E->OPC);
+ bc_t BC2 = GetBranchCond (N->OPC);
+
+ /* Check the branch conditions */
+ if (BC1 != GetInverseCond (BC2)) {
+ /* Condition not met */
+ goto NextEntry;
+ }
+
+ /* We may jump behind this conditional branch. This means that
+ * N may not be the last entry.
+ */
+ NI = GetCodeEntryIndex (S, N);
+ if (NI >= Count-1) {
+ /* N is last entry */
+ goto NextEntry;
+ }
+
+ /* Get the pointer to the next instruction */
+ X = GetCodeEntry (S, NI+1);
+
+ /* Get the label attached to X, create a new one if needed */
+ LX = GenCodeLabel (S, X);
+
+ /* Move the reference from E to the new label */
+ MoveCodeLabelRef (S, E, LX);
+
+ /* Remember, we had changes */
+ ++Changes;
+
+ /* Done */
+ continue;
+
+ }
}
NextEntry:
*/
{
unsigned Changes = 0;
- unsigned I;
+ unsigned I;
/* Get the number of entries, bail out if we have less than 2 entries */
unsigned Count = GetCodeEntryCount (S);
/*****************************************************************************/
-/* Remove conditional jumps never taken */
+/* Optimize conditional branches */
/*****************************************************************************/
-unsigned OptDeadCondBranches (CodeSeg* S)
-/* If an immidiate load of a register is followed by a conditional jump that
- * is never taken because the load of the register sets the flags in such a
- * manner, remove the conditional branch.
+unsigned OptCondBranches (CodeSeg* S)
+/* Performs several optimization steps:
+ *
+ * - If an immidiate load of a register is followed by a conditional jump that
+ * is never taken because the load of the register sets the flags in such a
+ * manner, remove the conditional branch.
+ * - If the conditional branch is always taken because of the register load,
+ * replace it by a jmp.
+ * - If a conditional branch jumps around an unconditional branch, remove the
+ * conditional branch and make the jump a conditional branch with the
+ * inverse condition of the first one.
*/
{
unsigned Changes = 0;
I = 0;
while (I < Count-1) {
+ CodeEntry* N;
+ CodeLabel* L;
+
/* Get next entry */
CodeEntry* E = GetCodeEntry (S, I);
/* Check if it's a register load */
- if ((E->Info & OF_LOAD) != 0 && E->AM == AM_IMM && (E->Flags & CEF_NUMARG) != 0) {
+ if ((E->Info & OF_LOAD) != 0 && /* It's a load instruction */
+ E->AM == AM_IMM && /* ..with immidiate addressing */
+ (E->Flags & CEF_NUMARG) != 0 && /* ..and a numeric argument. */
+ (N = GetNextCodeEntry (S, I)) != 0 && /* There is a following entry */
+ (N->Info & OF_CBRA) != 0 && /* ..which is a conditional branch */
+ !CodeEntryHasLabel (N)) { /* ..and does not have a label */
+
+ /* Get the branch condition */
+ bc_t BC = GetBranchCond (N->OPC);
- bc_t BC;
+ /* Check the argument against the branch condition */
+ if ((BC == BC_EQ && E->Num != 0) ||
+ (BC == BC_NE && E->Num == 0) ||
+ (BC == BC_PL && (E->Num & 0x80) != 0) ||
+ (BC == BC_MI && (E->Num & 0x80) == 0)) {
- /* Immidiate register load, get next instruction */
- CodeEntry* N = GetCodeEntry (S, I+1);
+ /* Remove the conditional branch */
+ DelCodeEntry (S, I+1);
+ --Count;
- /* Check if the following insn is a conditional branch or if it
- * has a label attached.
- */
- if ((N->Info & OF_CBRA) == 0 || CodeEntryHasLabel (E)) {
- /* No conditional jump or label attached, bail out */
+ /* Remember, we had changes */
+ ++Changes;
+
+ } else if ((BC == BC_EQ && E->Num == 0) ||
+ (BC == BC_NE && E->Num != 0) ||
+ (BC == BC_PL && (E->Num & 0x80) == 0) ||
+ (BC == BC_MI && (E->Num & 0x80) != 0)) {
+
+ /* The branch is always taken, replace it by a jump */
+ ReplaceOPC (N, OPC_JMP);
+
+ /* Remember, we had changes */
+ ++Changes;
+ }
+
+ }
+
+ if ((E->Info & OF_CBRA) != 0 && /* It's a conditional branch */
+ (L = E->JumpTo) != 0 && /* ..referencing a local label */
+ (N = GetNextCodeEntry (S, I)) != 0 && /* There is a following entry */
+ (N->Info & OF_UBRA) != 0 && /* ..which is an uncond branch, */
+ !CodeEntryHasLabel (N) && /* ..has no label attached */
+ L->Owner == GetNextCodeEntry (S, I+1)) {/* ..and jump target follows */
+
+ /* Replace the jump by a conditional branch with the inverse branch
+ * condition than the branch around it.
+ */
+ ReplaceOPC (N, GetInverseBranch (E->OPC));
+
+ /* Remove the conditional branch */
+ DelCodeEntry (S, I);
+ --Count;
+
+ /* Remember, we had changes */
+ ++Changes;
+
+ }
+
+ /* Next entry */
+ ++I;
+
+ }
+
+ /* Return the number of changes made */
+ return Changes;
+}
+
+
+
+/*****************************************************************************/
+/* Remove unused loads */
+/*****************************************************************************/
+
+
+
+unsigned OptUnusedLoads (CodeSeg* S)
+/* Remove loads of registers where the value loaded is not used later. */
+{
+ unsigned Changes = 0;
+ unsigned I;
+
+ /* Get the number of entries, bail out if we have not enough */
+ unsigned Count = GetCodeEntryCount (S);
+ if (Count < 2) {
+ return 0;
+ }
+
+ /* Walk over the entries */
+ I = 0;
+ while (I < Count-1) {
+
+ /* Get next entry */
+ CodeEntry* E = GetCodeEntry (S, I);
+
+ /* Check if it's a register load */
+ if ((E->Info & OF_LOAD) != 0) {
+
+ unsigned char R;
+
+ /* Get the next instruction, it must not be a conditional branch */
+ CodeEntry* N = GetCodeEntry (S, I+1);
+ if ((N->Info & OF_CBRA) != 0) {
goto NextEntry;
}
- /* Get the branch condition */
- BC = GetBranchCond (N->OPC);
+ /* Check which sort of load it is */
+ switch (E->OPC) {
+ case OPC_LDA: R = REG_A; break;
+ case OPC_LDX: R = REG_X; break;
+ case OPC_LDY: R = REG_Y; break;
+ default: goto NextEntry; /* OOPS */
+ }
- /* Check the argument against the branch condition */
- if ((BC == BC_EQ && E->Num != 0) ||
- (BC == BC_NE && E->Num == 0) ||
- (BC == BC_PL && (E->Num & 0x80) != 0) ||
- (BC == BC_MI && (E->Num & 0x80) == 0)) {
+ /* Get register usage and check if the register value is used later */
+ if ((GetRegInfo (S, I+1) & R) == 0) {
- /* Remove the conditional branch */
- DelCodeEntry (S, I+1);
+ /* Register value is not used, remove the load */
+ DelCodeEntry (S, I);
--Count;
/* Remember, we had changes */
/* Return the number of changes made */
return Changes;
-}
+}
* the branch gets removed.
*/
-unsigned OptDeadCondBranches (CodeSeg* S);
+unsigned OptCondBranches (CodeSeg* S);
/* If an immidiate load of a register is followed by a conditional jump that
* is never taken because the load of the register sets the flags in such a
* manner, remove the conditional branch.
*/
+unsigned OptUnusedLoads (CodeSeg* S);
+/* Remove loads of registers where the value loaded is not used later. */
+
/* End of coptind.h */
projects / cc65 / commitdiff