+// peeph-z80.def - Z80 peephole rules
+//
+//
+// (c) Philipp Klaus Krause (pkk@spth.de, philipp@colecovision.eu) 2006 - 2007
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option) any
+// later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+// This can't go into peeph.def since %1 could be (hl+) on gbz80.
replace restart {
- ld a,%1(%2)
- bit %3,a
- jp %4,%5
+ ld %1,%3
+ ld %1,%2
} by {
- bit %3,%1(%2)
- jp %4,%5
+ ; peephole z0 removed dead load into %1
+ ld %1,%2
+} if notVolatile(%1 %3), operandsNotSame
+
+replace restart {
+ ld %1,#%2
+ ld a,0(%1)
+ ld %3,a
+ ld %1,#%5
+} by {
+ ld a,(#%2)
+ ; peephole z1 used #%2 directly instead of going through %1 using indirect addressing.
+ ld %3,a
+ ld %1,#%5
}
-replace {
- ld %1,%2)
- ld a,%2)
+
+replace restart {
+ ld %1,#%2
+ ld 0(%1),a
+%4:
+ ld %1,%5
} by {
- ld %1,%2)
- ld a,%1
+ ld (#%2),a
+ ; peephole z2 directly used #%2 instead of going through %1 using indirect addressing.
+%4:
+ ld %1,%5
}
-replace {
- ld %1),a
- xor a,a
- or a,%1)
- jp z,%2
+
+replace restart {
+ pop af
+ ld %1,#%2
+ ld 0(%1),%3
+ ld %1,#%4
} by {
- ld %1),a
- or a,a
- jp z,%2
+ ld a,%3
+ ld (#%2),a
+ ; peephole z3 used #%2 directly instead of going through %1 using indirect addressing.
+ pop af
+ ld %1,#%4
+} if operandsNotRelated(%3 'a')
+
+replace restart {
+ ld bc,#%1 + %2
+ ld a,%3
+ ld (bc),a
+ ld bc,#%4 + %5
+} by {
+ ld a,%3
+ ld (#%1 + %2),a
+ ; peephole z4 directly used address #%1 + %2 instead of placing it in bc first.
+ ld bc,#%4 + %5
}
-replace {
- rlca
- ld a,#0x00
- rla
+
+replace restart {
+ ld bc,#%1 + %2 + %6
+ ld a,%3
+ ld (bc),a
+ ld bc,#%4 + %5
} by {
- rlca
- and a,#0x01
+ ld a,%3
+ ld (#%1 + %2 + %6),a
+ ; peephole z5 directly used address #%1 + %2 + %6 instead of placing it in bc first.
+ ld bc,#%4 + %5
}
-replace {
- ld %3,a
- ld l,%1)
- ld h,%2)
- ld l,(hl)
+
+replace restart {
+ ld bc,#%1 + %2
ld a,%3
+ ld (bc),a
+%7:
+ ld bc,#%4 + %5
} by {
- ld %3,a
- ld l,%1)
- ld h,%2)
- ld l,(hl)
+ ld a,%3
+ ld (#%1 + %2),a
+ ; peephole z6 directly used address #%1 + %2 instead of placing it in bc first.
+%7:
+ ld bc,#%4 + %5
}
+
+replace restart {
+ ld bc,#%1 + %2 + %6
+ ld a,%3
+ ld (bc),a
+%7:
+ ld bc,#%4 + %5
+} by {
+ ld a,%3
+ ld (#%1 + %2 + %6),a
+ ; peephole z7 directly used address #%1 + %2 + %6 instead of placing it in bc first.
+%7:
+ ld bc,#%4 + %5
+}
+
+replace restart {
+ ld c,%1
+ ld l,c
+ ret
+} by {
+ ld l,%1
+ ; peephole z8 moved %1 directly into l instead of going through c.
+ ret
+}
+
+replace restart {
+ ld b,h
+ ld c,l
+ pop af
+ push bc
+ call %1
+} by {
+ ex (sp),hl
+ ; peephole z9 moved hl directly to the stack instead of going through bc.
+ call %1
+}
+
+replace restart {
+ ld d,h
+ ld e,l
+ pop af
+ push de
+ call %1
+} by {
+ ex (sp),hl
+ ; peephole z10 moved hl directly to the stack instead of going through de.
+ call %1
+}
+
+replace restart {
+ jp %5
+} by {
+ ret
+ ; peephole z11 replaced jump by return.
+} if labelIsReturnOnly(), labelRefCountChange(%5 -1)
+
+replace restart {
+ jp %1,%5
+} by {
+ ret %1
+ ; peephole z11a replaced jump by return.
+} if labelIsReturnOnly(), labelRefCountChange(%5 -1)
+
+// Should be one of the last ones. Opens the code to further peephole optimization.
+replace restart {
+%1:
+} by {
+ ; peephole z12 removed unused label %1.
+} if labelRefCount(%1 0)
+
+// Applying z11 or z11a followed by z12 will often leave a dead ret at the end of the function. Remove it.
+replace {
+ jp %5
+ ret
+} by {
+ jp %5
+ ; peephole z13 removed unused ret.
+}
+
+// These should be the last rules, so that the peepholes above need to look at jp only.
+replace {
+ jp %5
+} by {
+ jr %5
+ ; peephole z14 changed absolute to relative unconditional jump.
+} if labelInRange()
+
+replace {
+ jp Z,%5
+} by {
+ jr Z,%5
+ ; peephole z15 changed absolute to relative conditional jump.
+} if labelInRange()
+
+replace {
+ jp NZ,%5
+} by {
+ jr NZ,%5
+ ; peephole z16 changed absolute to relative conditional jump.
+} if labelInRange()
+
+replace {
+ jp C,%5
+} by {
+ jr C,%5
+ ; peephole z17 changed absolute to relative conditional jump.
+} if labelInRange()
+
+replace {
+ jp NC,%5
+} by {
+ jr NC,%5
+ ; peephole z18 changed absolute to relative conditional jump.
+} if labelInRange()
projects / fw / sdcc / blobdiff