/*****************************************************************************/
/* */
-/* coptind.h */
+/* coptind.h */
/* */
-/* Environment independent low level optimizations */
+/* Environment independent low level optimizations */
/* */
/* */
/* */
-/* (C) 2001 Ullrich von Bassewitz */
-/* Wacholderweg 14 */
-/* D-70597 Stuttgart */
-/* EMail: uz@cc65.org */
+/* (C) 2001-2009, Ullrich von Bassewitz */
+/* Roemerstrasse 52 */
+/* D-70794 Filderstadt */
+/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
+/* cc65 */
#include "codeseg.h"
/*****************************************************************************/
-/* Code */
+/* Code */
/*****************************************************************************/
-unsigned OptRTSJumps (CodeSeg* S);
+unsigned OptRTSJumps1 (CodeSeg* S);
/* Replace jumps to RTS by RTS */
+unsigned OptRTSJumps2 (CodeSeg* S);
+/* Replace long conditional jumps to RTS */
+
unsigned OptDeadJumps (CodeSeg* S);
/* Remove dead jumps (jumps to the next instruction) */
* label, the dead code elimination should take care of it.
*/
-unsigned OptJumpTarget (CodeSeg* S);
+unsigned OptJumpTarget1 (CodeSeg* S);
/* If the instruction preceeding an unconditional branch is the same as the
* instruction preceeding the jump target, the jump target may be moved
* one entry back. This is a size optimization, since the instruction before
* the branch gets removed.
*/
-unsigned OptCondBranches (CodeSeg* S);
+unsigned OptJumpTarget2 (CodeSeg* S);
+/* If a bcs jumps to a sec insn or a bcc jumps to clc, skip this insn, since
+ * it's job is already done.
+ */
+
+unsigned OptJumpTarget3 (CodeSeg* S);
+/* Jumps to load instructions of a register, that do already have the matching
+ * register contents may skip the load instruction, since it's job is already
+ * done.
+ */
+
+unsigned OptCondBranches1 (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 OptCondBranches2 (CodeSeg* S);
+/* If on entry to a "rol a" instruction the accu is zero, and a beq/bne follows,
+ * we can remove the rol and branch on the state of the carry.
+ */
+
unsigned OptUnusedLoads (CodeSeg* S);
/* Remove loads of registers where the value loaded is not used later. */
unsigned OptUnusedStores (CodeSeg* S);
/* Remove stores into zero page registers that aren't used later */
-unsigned OptDuplicateLoads (CodeSeg* S);
+unsigned OptDupLoads (CodeSeg* S);
/* Remove loads of registers where the value loaded is already in the register. */
unsigned OptStoreLoad (CodeSeg* S);
/* Remove a store followed by a load from the same location. */
-unsigned OptTransfers (CodeSeg* S);
+unsigned OptTransfers1 (CodeSeg* S);
/* Remove transfers from one register to another and back */
+unsigned OptTransfers2 (CodeSeg* S);
+/* Replace loads followed by a register transfer by a load with the second
+ * register if possible.
+ */
+
+unsigned OptTransfers3 (CodeSeg* S);
+/* Replace a register transfer followed by a store of the second register by a
+ * store of the first register if this is possible.
+ */
+
+unsigned OptTransfers4 (CodeSeg* S);
+/* Replace a load of a register followed by a transfer insn of the same register
+ * by a load of the second register if possible.
+ */
+
+unsigned OptPushPop (CodeSeg* S);
+/* Remove a PHA/PLA sequence were A is not used later */
+
+unsigned OptPrecalc (CodeSeg* S);
+/* Replace immediate operations with the accu where the current contents are
+ * known by a load of the final value.
+ */
+
unsigned OptBranchDist (CodeSeg* S);
/* Change branches for the distance needed. */
+unsigned OptIndLoads1 (CodeSeg* S);
+/* Change
+ *
+ * lda (zp),y
+ *
+ * into
+ *
+ * lda (zp,x)
+ *
+ * provided that x and y are both zero.
+ */
+unsigned OptIndLoads2 (CodeSeg* S);
+/* Change
+ *
+ * lda (zp,x)
+ *
+ * into
+ *
+ * lda (zp),y
+ *
+ * provided that x and y are both zero.
+ */
-/* End of coptind.h */
-#endif
+/* End of coptind.h */
+#endif