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Analysis of cycle costs for SH4:

-> udiv_le128:            5
-> udiv_ge64k:            6
-> udiv udiv_25:         10
-> pos_divisor:           3
-> pos_result linear:     5
-> pos_result - -:        5
-> div_le128:             7
-> div_ge64k:             9
sdivsi3 -> udiv_25             13
udiv25 -> div_ge64k_end:       15
div_ge64k_end -> rts:          13
div_le128 -> div_le128_2:       2, r1 latency 3
udiv_le128 -> div_le128_2:      2, r1 latency 3
(u)div_le128 -> div_by_1:       9
(u)div_le128 -> rts:           17
div_by_1(_neg) -> rts:          4
div_ge64k -> div_r8:            2
div_ge64k -> div_ge64k_2:       3
udiv_ge64k -> udiv_r8:          3
udiv_ge64k -> div_ge64k_2:      3 + LS
(u)div_ge64k -> div_ge64k_end: 13
div_r8 -> div_r8_2:             2
udiv_r8 -> div_r8_2:            2 + LS
(u)div_r8 -> rts:              21

-> - + neg_result:             5
-> + - neg_result:             5
-> div_le128_neg:              7
-> div_ge64k_neg:              9
-> div_r8_neg:                11
-> <64k div_ge64k_neg_end:    28
-> >=64k div_ge64k_neg_end:   22
div_ge64k_neg_end ft -> rts:  14
div_r8_neg_end -> rts:         4
div_r8_neg -> div_r8_neg_end: 18
div_le128_neg -> div_by_1_neg: 4
div_le128_neg -> rts          18

         sh4-200    absolute divisor range:
            1  [2..128]  [129..64K) [64K..|dividend|/256] >=64K,>|dividend/256|
udiv       18     22         38            32                   30
sdiv pos:  20     24         41            35                   32
sdiv neg:  15     25         42            36                   33

         sh4-300    absolute divisor range:
                 8 bit      16 bit       24 bit              > 24 bit
udiv              15         35            28                   25
sdiv              14         36            34                   31


fp-based:

unsigned: 42 + 3 + 3 (lingering ftrc latency + sts fpul,rx) at caller's site
signed: 33 + 3 + 3 (lingering ftrc latency + sts fpul,rx) at caller's site

call-div1:    divisor range:
              [1..64K)  >= 64K
unsigned:       63        58
signed:         76        76

SFUNC_STATIC call overhead:
mov.l 0f,r1
bsrf r1

SFUNC_GOT call overhead - current:
mov.l 0f,r1
mova 0f,r0
mov.l 1f,r2
add r1,r0
mov.l @(r0,r2),r0
jmp @r0
; 3 cycles worse than SFUNC_STATIC

SFUNC_GOT call overhead - improved assembler:
mov.l 0f,r1
mova 0f,r0
mov.l @(r0,r1),r0
jmp @r0
; 2 cycles worse than SFUNC_STATIC


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