+// peeph.def - Common Z80 and gbz80 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.
+
replace restart {
- ld %1,%1
+ ld %1,%1
} by {
- ; Removed redundent load
-}
+ ; peephole 1 removed redundant load.
+} if notVolatile(%1)
+
replace restart {
- xor a,a
- or a,%1
- or a,a
- jp %2,%3
+ ld %1,%3
+ ld %1,%2
} by {
- ; Removed redundent or a,a
- xor a,a
- or a,%1
- jp %2,%3
-}
+ ; peephole 2 removed dead load into %1
+ ld %1,%2
+} if notVolatile(%1 %3), operandsNotSame
+
replace restart {
- cp a,#0x00
- jp nz,%1
+ jp NC,%1
+ jp %2
+%1:
} by {
- ; Rule 3
- or a,a
- jp nz,%1
-}
+ jp C,%2
+ ; peephole 3 removed jp by using inverse jump logic
+%1:
+} if labelRefCountChange(%1 -1)
+
replace restart {
- jp nz,%1
+ jp C,%1
jp %2
%1:
- jp %3
-%2:
} by {
- ; Rule 4
- jp z,%2
+ jp NC,%2
+ ; peephole 4 removed jp by using inverse jump logic
%1:
- jp %3
-%2:
-}
+} if labelRefCountChange(%1 -1)
+
replace restart {
- jp nz,%1
+ jp NZ,%1
jp %2
%1:
} by {
- ; Rule 5
- jp z,%2
+ jp Z,%2
+ ; peephole 5 removed jp by using inverse jump logic
%1:
-}
+} if labelRefCountChange(%1 -1)
+
replace restart {
- jp z,%1
+ jp Z,%1
jp %2
%1:
} by {
- ; Rule 6
- jp nz,%2
+ jp NZ,%2
+ ; peephole 6 removed jp by using inverse jump logic
%1:
+} if labelRefCountChange(%1 -1)
+
+replace restart {
+ jp %5
+} by {
+ jp %6
+ ; peephole 7 redirected jump-to-jump at %5 by jump to %6
+} if labelIsUncondJump(), labelRefCountChange(%5 -1), labelRefCountChange(%6 +1)
+
+replace restart {
+ jp %1,%5
+} by {
+ jp %1,%6
+ ; peephole 8 redirected jump-to-jump at %5 by jump to %6
+} if labelIsUncondJump(), labelRefCountChange(%5 -1), labelRefCountChange(%6 +1)
+
+replace restart {
+ ld %2,%3
+ jp %4
+%5:
+ ld %2,%3
+%4:
+} by {
+ ; peephole 9 removed jump and redundant load.
+%5:
+ ld %2,%3
+%4:
+} if labelRefCountChange(%4 -1)
+
+replace restart {
+ xor a,a
+ ld a,#0x00
+} by {
+ xor a,a
+ ; peephole 10 removed redundant load of 0 into a.
+}
+
+replace {
+ ld e,#0x%1
+ ld d,#0x%2
+} by {
+ ld de,#0x%2%1
+ ; peephole 11 combined constant loads into register pair.
+}
+
+replace {
+ ld l,#0x%1
+ ld h,#0x%2
+} by {
+ ld hl,#0x%2%1
+ ; peephole 12 combined constant loads into register pair.
+}
+
+replace {
+ ld c,#0x%1
+ ld b,#0x%2
+} by {
+ ld bc,#0x%2%1
+ ; peephole 13 combined constant loads into register pair.
}
+
replace restart {
+ ld %1,a
ld a,%1
+} by {
+ ld %1,a
+ ; peephole 14 removed redundant load from %1 into a.
+} if notVolatile(%1)
+// This gives many false negatives and without the test no problems are encountered in the regression tests
+// Maybe we can try this after 2.7.0 release
+
+replace restart {
+ ld a,%1
+ ld %1,a
+} by {
+ ld a,%1
+ ; peephole 15 removed redundant load from a into %1.
+} if notVolatile(%1)
+// This gives many false negatives and without the test no problems are encountered in the regression tests
+// Maybe we can try this after 2.7.0 release
+
+replace restart {
+ ld %2,%3
+ ld a,%2
+ and a,%1
+ ld %2,%4
+} by {
+ ld a,%3
+ ; peephole 16 moved %3 directly into a instead of going through %2.
+ and a,%1
+ ld %2,%4
+} if notVolatile(%2), operandsNotSame
+
+replace restart {
+ ld %1,a
+ ld a,%2
+ or a,%1
+} by {
+ ld %1,a
or a,%2
+ ; peephole 17 removed load by reordering or arguments.
+} if notVolatile(%1)
+
+replace restart {
+ ld %1,a
+ xor a,a
+ or a,%1
+} by {
+ ld %1,a
+ or a,a
+ ; peephole 18 used value still in a instead of loading it from %1.
+}
+
+replace restart {
+ or a,%1
+ or a,a
+} by {
+ or a,%1
+ ; peephole 19 removed redundant or after or.
+}
+
+replace restart {
+ and a,%1
+ or a,a
+} by {
+ and a,%1
+ ; peephole 20 removed redundant or after and.
+}
+
+replace restart {
+ xor a,%1
or a,a
} by {
- ; Rule 8
+ xor a,%1
+ ; peephole 21 removed redundant or after xor.
+}
+
+replace restart {
+ ld %1,a
+ and a,%2
+ ld %1,a
+} by {
+ ; peephole 22 removed redundant load into %1.
+ and a,%2
+ ld %1,a
+} if notVolatile(%1)
+
+replace {
+ ld %1,%2
+ ld a,%2
+} by {
+ ld a,%2
+ ld %1,a
+ ; peephole 23 load value in a first and use it next
+} if notVolatile(%1 %2)
+
+replace restart {
+ ld %1,%2
+ ld %3,%4
+ ld %2,%1
+ ld %4,%3
+} by {
+ ld %1,%2
+ ld %3,%4
+ ; peephole 24 removed redundant load from %3%1 into %4%2
+} if notVolatile(%1 %2 %3 %4)
+
+replace restart {
+ ld b,%1
+ ld a,b
+ pop bc
+} by {
ld a,%1
+ ; peephole 25 removed load into b
+ pop bc
+}
+
+replace restart {
+ ld c,%1
+ ld a,c
+ pop bc
+} by {
+ ld a,%1
+ ; peephole 26 removed load into c
+ pop bc
+}
+
+replace restart {
+ ld d,%1
+ ld a,d
+ pop de
+} by {
+ ld a,%1
+ ; peephole 27 removed load into d
+ pop de
+}
+
+replace restart {
+ ld e,%1
+ ld a,e
+ pop de
+} by {
+ ld a,%1
+ ; peephole 28 removed load into e
+ pop de
+}
+
+replace restart {
+ ld h,%1
+ ld a,h
+ pop hl
+} by {
+ ld a,%1
+ ; peephole 29 removed load into h
+ pop hl
+}
+
+replace restart {
+ ld l,%1
+ ld a,l
+ pop hl
+} by {
+ ld a,%1
+ ; peephole 30 removed load into l
+ pop hl
+}
+
+replace restart {
+ ld a,c
+ push af
+ inc sp
+ ld a,#%2
+ push af
+ inc sp
+ call %3
+} by {
+ ld b,c
+ ld c,#%2
+ push bc
+ ; peephole 31 moved and pushed arguments c and #%2 through bc instead of pushing them individually.
+ call %3
+}
+
+replace restart {
+ ld a,e
+ push af
+ inc sp
+ ld a,#%2
+ push af
+ inc sp
+ call %3
+} by {
+ ld d,e
+ ld e,#%2
+ push de
+ ; peephole 32 moved and pushed arguments e and #%2 through de instead of pushing them individually.
+ call %3
+}
+
+replace restart {
+ ld a,%1
+ sub a,%2
+ jp %3,%4
+ ld a,%1
+} by {
+ ld a,%1
+ cp a,%2
+ jp %3,%4
+ ; peephole 33 removed load by replacing sub with cp
+ assert a=%1
+} if notVolatile(%1)
+
+replace restart {
+ assert a=%1
+ sub a,%2
+ jp %3,%4
+ ld a,%1
+} by {
+ cp a,#%2
+ jp %3,%4
+ ; peephole 34 removed load by replacing sub with cp
+ assert a=%1
+}
+
+replace restart {
+ assert a=%1
+} by {
+}
+
+replace restart {
+ sub a,#0xFF
+ jp Z,%1
+} by {
+ inc a
+ ; peephole 35 replaced sub a,#0xFF by inc a.
+ jp Z,%1
+}
+
+replace restart {
+ sub a,#0xFF
+ jp NZ,%1
+} by {
+ inc a
+ ; peephole 36 replaced sub a,#0xFF by inc a.
+ jp NZ,%1
+}
+
+replace restart {
+ ld bc,#%1 + %2
+ ld a,c
+ add a,%3
+ ld c,a
+ ld a,b
+ adc a,%4
+ ld b,a
+} by {
+ ld a,#<(%1 + %2)
+ add a,%3
+ ld c,a
+ ld a,#>(%1 + %2)
+ ; peephole 37 directly used (%1 + %2) in calculation instead of placing it in bc first.
+ adc a,%4
+ ld b,a
+}
+
+replace restart {
+ ld de,#%1 + %2
+ ld a,e
+ add a,%3
+ ld e,a
+ ld a,d
+ adc a,%4
+ ld d,a
+} by {
+ ld a,#<(%1 + %2)
+ add a,%3
+ ld e,a
+ ld a,#>(%1 + %2)
+ ; peephole 38 directly used (%1 + %2) in calculation instead of placing it in de first.
+ adc a,%4
+ ld d,a
+}
+
+replace restart {
+ rlca
+ ld a,#0x00
+ rla
+} by {
+ rlca
+ and a,#0x01
+ ; peephole 39 replaced zero load, rla by and since rlca writes the same value to carry bit and least significant bit.
+}
+
+replace restart {
+ ld %1,%2
+ push %1
+ pop %4
+ ld %1,%3
+} by {
+ ld %4,%2
+ ; peephole 40 moved %2 directly into de instead of going through %1.
+ ld %1,%3
+}
+
+replace restart {
+ add a,#0x00
+ ld %2,a
+ ld a,%3
+ adc a,%4
+} by {
+ ; peephole 41 removed lower part of multibyte addition.
+ ld %2,a
+ ld a,%3
+ add a,%4
+}
+
+replace restart {
+ ld %1,a
+ ld a,%2
+ add a,%1
+ ld %1,a
+} by {
+ ; peephole 42 removed loads by exploiting commutativity of addition.
+ add a,%2
+ ld %1,a
+} if notVolatile(%1)
+
+// sdcc does not use the H flag. sla resets it, while add sets it.
+// To ensure that the state of the H flag is not changed by this
+// peephole uncomment the add %3, %4 at the end (since it overwrite the H flag).
+replace restart {
+ ld %1, a
+ sla %1
+ ld a, %2
+ //add %3, %4
+} by {
+ add a, a
+ ; peephole 42a shifts in accumulator insted of %1
+ ld %1, a
+ ld a, %2
+ //add %3, %4
+}
+
+replace restart {
+ ld %1,a
+ ld a,%2
+ add a,%1
+} by {
+ ld %1, a
+ ; peephole 43 removed load by exploiting commutativity of addition.
+ add a,%2
+}
+
+replace restart {
+ or a,%1
+ jp NZ,%2
+ xor a,a
+ or a,%3
+} by {
+ or a,%1
+ jp NZ,%2
+ ; peephole 44 removed redundant zeroing of a (which has just been tested to be #0x00).
+ or a,%3
+}
+
+replace restart {
+ or a,%1
+ jp NZ,%2
+ ld %3,#0x00
+} by {
+ or a,%1
+ jp NZ,%2
+ ld %3,a
+ ; peephole 45 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ and a,%1
+ jp NZ,%2
+ ld %3,#0x00
+} by {
+ and a,%1
+ jp NZ,%2
+ ld %3,a
+ ; peephole 46 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ sub a,%1
+ jp NZ,%2
+ ld %3,#0x00
+} by {
+ sub a,%1
+ jp NZ,%2
+ ld %3,a
+ ; peephole 47 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ dec a
+ jp NZ,%1
+ ld %2,#0x00
+} by {
+ dec a
+ jp NZ,%1
+ ld %2,a
+ ; peephole 48 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ or a,%1
+ jp NZ,%2
+ ld a,%3
+ or a,a
+} by {
+ or a,%1
+ jp NZ,%2
+ or a,%3
+ ; peephole 49 shortened or using a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ and a,%1
+ jp NZ,%2
+ ld a,%3
+ or a,a
+} by {
+ and a,%1
+ jp NZ,%2
+ or a,%3
+ ; peephole 50 shortened or using a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ sub a,%1
+ jp NZ,%2
+ ld a,%3
+ or a,a
+} by {
+ sub a,%1
+ jp NZ,%2
+ or a,%3
+ ; peephole 51 shortened or using a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ dec a
+ jp NZ,%1
+ ld a,%2
+ or a,a
+} by {
+ dec a
+ jp NZ,%1
or a,%2
+ ; peephole 52 shortened or using a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ or a,%1
+ jp NZ,%2
+ push %3
+ ld %4,#0x00
+} by {
+ or a,%1
+ jp NZ,%2
+ push %3
+ ld %4,a
+ ; peephole 53 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ and a,%1
+ jp NZ,%2
+ push %3
+ ld %4,#0x00
+} by {
+ sub a,%1
+ jp NZ,%2
+ push %3
+ ld %4,a
+ ; peephole 54 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ sub a,%1
+ jp NZ,%2
+ push %3
+ ld %4,#0x00
+} by {
+ sub a,%1
+ jp NZ,%2
+ push %3
+ ld %4,a
+ ; peephole 55 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ dec a
+ jp NZ,%1
+ push %2
+ ld %3,#0x00
+} by {
+ dec a
+ jp NZ,%1
+ push %2
+ ld %3,a
+ ; peephole 56 replaced constant #0x00 by a (which has just been tested to be #0x00).
+}
+
+replace restart {
+ ld de,#%1 + %2
+ inc de
+ inc de
+ inc de
+} by {
+ ld de,#%1 + %2 + 3
+ ; peephole 57 moved triple increment of de to constant.
+}
+
+replace restart {
+ ld de,#%1 + %2
+ inc de
+ inc de
+} by {
+ ld de,#%1 + %2 + 2
+ ; peephole 58 moved double increment of de to constant.
+}
+
+replace restart {
+ ld de,#%1 + %2
+ inc de
+} by {
+ ld de,#%1 + %2 + 1
+ ; peephole 59 moved increment of de to constant.
+}
+
+replace restart {
+ ld bc,#%1 + %2
+ inc bc
+ inc bc
+ inc bc
+} by {
+ ld bc,#%1 + %2 + 3
+ ; peephole 60 moved triple increment of bc to constant.
+}
+
+replace restart {
+ ld bc,#%1 + %2
+ inc bc
+ inc bc
+} by {
+ ld bc,#%1 + %2 + 2
+ ; peephole 61 moved double increment of bc to constant.
+}
+
+replace restart {
+ ld bc,#%1 + %2
+ inc bc
+} by {
+ ld bc,#%1 + %2 + 1
+ ; peephole 62 moved increment of bc to constant.
+}
+
+replace restart {
+ ld bc,#%1
+ ld a,c
+ add a,#0x%2
+ ld c,a
+ ld a,b
+ adc a,#0x%3
+ ld b,a
+} by {
+ ld bc,#%1 + 0x%3%2
+ ; peephole 63 moved addition of constant 0x%3%2 to bc to constant.
+}
+
+replace restart {
+ ld bc,#%1 + %4
+ ld a,c
+ add a,#0x%2
+ ld c,a
+ ld a,b
+ adc a,#0x%3
+ ld b,a
+} by {
+ ld bc,#%1 + %4 + 0x%3%2
+ ; peephole 64 moved addition of constant 0x%3%2 to bc to constant.
+}
+
+replace restart {
+ call %1
+ ret
+} by {
+ jp %1
+ ; peephole 65 replaced call at end of function by jump.
+}
+
+// Callee saves ix.
+replace restart {
+ call %1
+ pop ix
+ ret
+} by {
+ pop ix
+ jp %1
+ ; peephole 66 replaced call at end of function by jump moving call beyond pop ix.
}
projects / fw / sdcc / blobdiff