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|
replace {
pula
psha
lda %1
} by {
; Peephole 1a - removed redundant pula/psha
lda %1
}
replace {
pula
psha
lda %1,s
} by {
; Peephole 1b - removed redundant pula/psha
lda %1,s
}
replace {
pula
psha
clra
} by {
; Peephole 1c - removed redundant pula/psha
clra
}
replace {
bcs %1
jmp %5
%1:
} by {
; Peephole 2a - eliminated jmp
bcc %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bcc %1
jmp %5
%1:
} by {
; Peephole 2b - eliminated jmp
bcs %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
beq %1
jmp %5
%1:
} by {
; Peephole 2c - eliminated jmp
bne %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bne %1
jmp %5
%1:
} by {
; Peephole 2d - eliminated jmp
beq %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
brclr %3,%2,%1
jmp %5
%1:
} by {
; Peephole 2e - eliminated jmp
brset %3,%2,%5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
brset %3,%2,%1
jmp %5
%1:
} by {
; Peephole 2f - eliminated jmp
brclr %3,%2,%5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bls %1
jmp %5
%1:
} by {
; Peephole 2g - eliminated jmp
bhi %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bhi %1
jmp %5
%1:
} by {
; Peephole 2h - eliminated jmp
bls %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
ble %1
jmp %5
%1:
} by {
; Peephole 2i - eliminated jmp
bgt %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bgt %1
jmp %5
%1:
} by {
; Peephole 2j - eliminated jmp
ble %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bge %1
jmp %5
%1:
} by {
; Peephole 2k - eliminated jmp
blt %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
blt %1
jmp %5
%1:
} by {
; Peephole 2l - eliminated jmp
bge %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bmi %1
jmp %5
%1:
} by {
; Peephole 2m - eliminated jmp
bpl %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace {
bpl %1
jmp %5
%1:
} by {
; Peephole 2n - eliminated jmp
bmi %5
%1:
} if labelInRange(%5), labelRefCountChange(%1 -1)
replace restart {
jmp %5
} by {
; Peephole 3 - shortened jmp to bra
bra %5
} if labelInRange(%5)
replace {
lda %1
tsta
} by {
; Peephole 4a - eliminated redundant tsta
lda %1
}
replace {
ldx %1
tstx
} by {
; Peephole 4b - eliminated redundant tstx
ldx %1
}
replace {
jmp %5
} by {
; Peephole 6a - replaced jmp to rts with rts
rts
} if optimizeReturn(), labelIsReturnOnly(%5), labelRefCountChange(%5 -1)
replace {
bra %5
} by {
; Peephole 6b - replaced jmp to rts with rts
rts
} if optimizeReturn(), labelIsReturnOnly(%5), labelRefCountChange(%5 -1)
replace {
bne %1
%1:
} by {
; Peephole 7a - eliminated branch
%1:
} if labelRefCountChange(%1 -1)
replace {
beq %1
%1:
} by {
; Peephole 7b - eliminated branch
%1:
} if labelRefCountChange(%1 -1)
replace restart {
bra %1
%1:
} by {
; Peephole 7c - eliminated branch
%1:
} if labelRefCountChange(%1 -1)
replace restart {
bra %1
%2:
%1:
} by {
; Peephole 7d - eliminated branch
%2:
%1:
} if labelRefCountChange(%1 -1)
replace {
cmp #%2
beq %1
} by {
; Peephole 10a - combined cmp/beq
cbeqa #%2,%1
}
replace {
cmp *%2
beq %1
} by {
; Peephole 10b - combined cmp/beq
cbeq *%2,%1
}
replace {
dec %2,s
bne %1
} by {
; Peephole 10c - combined dec/bne
dbnz %2,s,%1
}
// should be one of the last peepholes
replace restart {
%1:
} by {
; Peephole 500 removed redundant label %1
} if labelRefCount(%1 0)
replace restart {
jsr %1
rts
} by {
; Peephole 501 did tail call optimization.
jmp %1
} if optimizeReturn()
|
