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Now the code is prepared for easier analysis.
The control flow is less complex, there are fewer (or no) unused opcodes
and labels and no more stateful conditional codes handling.
At this stage, high level language constructs are ready to be
detected.
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.section ".rodata1",#alloc
.align 4
.l0:
.asciz "%u %u\n"
.section ".text",#alloc,#execinstr
.align 4
.global main
main:
save %sp,-96,%sp
set .l0,%i0
mov 1,%i1
clr %o1
mov 1,%o0
clr %i2
.l1:
cmp %i1,1
be .l7
nop
.l2:
srl %o0,1,%g2
btst 1,%o0
bne .l3
nop
inc %i2
srl %o0,1,%o0
ba .l4
nop
.l3:
add %o0,%g2,%g2
inc 2,%i2
add %g2,1,%o2
cmp %o2,%o0
bcs .l6
nop
mov %o2,%o0
.l4:
cmp %o0,1
bne .l2
nop
.l7:
cmp %i2,%o1
bgu 1f
nop
inc %i1
ba .l9
nop
1:
mov %i0,%o0
mov %i1,%o1
mov %i2,%o2
call printf
nop
inc %i1
mov %i2,%o1
.l9:
mov %i1,%o0
clr %i2
ba .l1
nop
.l6:
restore %g0,0,%o0
retl
nop
.type main,2
.size main,(.-main)
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What's next?
A next step is to identify code
repetitions which are introduced by optimizers to e.g. minimize
branches or work around inefficiencies in loop entry, and also
to duplicate delay slot operation into the first iteration.
Now seems to be the right time for a flow chart for further code
analysis.
The SPARC Architecture Manual,
Version 8,
SPARC International,
Prentice Hall,
1992
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