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#mach: crisv32
#output: Basic clock cycles, total @: 54\n
#output: Memory source stall cycles: 0\n
#output: Memory read-after-write stall cycles: 0\n
#output: Movem source stall cycles: 0\n
#output: Movem destination stall cycles: 0\n
#output: Movem address stall cycles: 0\n
#output: Multiplication source stall cycles: 0\n
#output: Jump source stall cycles: 0\n
#output: Branch misprediction stall cycles: 18\n
#output: Jump target stall cycles: 0\n
#sim: --cris-cycles=basic
; Check branch penalties. It is assumed that the taken-counters
; in the bimodal branch-predictors start at 0, meaning two taken
; branches are required for a branch to be predicted as taken
; for each counter, from reset. None of these branches go
; to the end of a cache-line and none map to the same counter.
.include "testutils.inc"
startnostack
ba 0f ; No penalty: always-taken condition not "predicted".
nop
nop
0:
setf c
bcs 0f ; Penalty 2 cycles.
nop
nop
0:
clearf c
bcc 0f ; Penalty 2 cycles, though branch is a nop.
moveq 4,r0 ; Execute 5 times:
0:
move.d r0,r0
bne 0b ; Mispredicted 3 out of 5 times: penalty 3*2 cycles.
subq 1,r0
0:
beq 0f ; Not taken; no penalty.
nop
nop
0:
; (Almost) same insns, but with 16-bit bCC insns.
ba 0f ; No penalty: always-taken condition not "predicted".
nop
.space 520
0:
setf c
bcs 0f ; Penalty 2 cycles.
nop
.space 520
0:
moveq 4,r0 ; Execute 5 times:
0:
ba 1f
move.d r0,r0 ; Mispredicted 3 out of 5 times:
.space 520
1:
bne 0b ; Penalty 3*2 cycles.
subq 1,r0
beq 0f ; Not taken; no penalty.
nop
0:
break 15
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