Before (without minsize):
100083ca <udiv64_slow>:
udiv64_slow():
/proc/self/cwd/sw/device/lib/base/math.c:14
100083ca: 1141 addi sp,sp,-16
100083cc: c622 sw s0,12(sp)
100083ce: 4881 li a7,0
100083d0: 4801 li a6,0
100083d2: 4381 li t2,0
100083d4: 4e01 li t3,0
100083d6: 03f00f93 li t6,63
100083da: 00159293 slli t0,a1,0x1
100083de: 537d li t1,-1
/proc/self/cwd/sw/device/lib/base/math.c:28
100083e0: /-------> fe0f8793 addi a5,t6,-32
100083e4: | /-- 0007c963 bltz a5,100083f6 <udiv64_slow+0x2c>
100083e8: | | 01f5deb3 srl t4,a1,t6
100083ec: | /--|-- a829 j 10008406 <udiv64_slow+0x3c>
100083ee: | | | c0001073 unimp
100083f2: | | | c0001073 unimp
100083f6: | | \-> 01f55eb3 srl t4,a0,t6
100083fa: | | ffffc793 not a5,t6
100083fe: | | 00f297b3 sll a5,t0,a5
10008402: | | 00feeeb3 or t4,t4,a5
10008406: | \----> 01f3d793 srli a5,t2,0x1f
1000840a: | 0e06 slli t3,t3,0x1
1000840c: | 00fe6e33 or t3,t3,a5
10008410: | 0386 slli t2,t2,0x1
10008412: | 001ef793 andi a5,t4,1
10008416: | 0077eeb3 or t4,a5,t2
/proc/self/cwd/sw/device/lib/base/math.c:34
1000841a: | /----- 00de0963 beq t3,a3,1000842c <udiv64_slow+0x62>
1000841e: | | 00de37b3 sltu a5,t3,a3
10008422: | | /-- a039 j 10008430 <udiv64_slow+0x66>
10008424: | | | c0001073 unimp
10008428: | | | c0001073 unimp
1000842c: | \--|-> 00ceb7b3 sltu a5,t4,a2
10008430: | \-> 0017cf13 xori t5,a5,1
10008434: | 01f8d793 srli a5,a7,0x1f
10008438: | 0806 slli a6,a6,0x1
1000843a: | 00f86833 or a6,a6,a5
1000843e: | 0886 slli a7,a7,0x1
10008440: | 41e007b3 neg a5,t5
10008444: | 00d7f433 and s0,a5,a3
10008448: | 8ff1 and a5,a5,a2
1000844a: | 40fe83b3 sub t2,t4,a5
1000844e: | 00feb7b3 sltu a5,t4,a5
10008452: | 408e0433 sub s0,t3,s0
10008456: | 40f40e33 sub t3,s0,a5
/proc/self/cwd/sw/device/lib/base/math.c:25
1000845a: | 1ffd addi t6,t6,-1
/proc/self/cwd/sw/device/lib/base/math.c:34
1000845c: | 01e8e8b3 or a7,a7,t5
/proc/self/cwd/sw/device/lib/base/math.c:25
10008460: \-------- f86f90e3 bne t6,t1,100083e0 <udiv64_slow+0x16>
/proc/self/cwd/sw/device/lib/base/math.c:40
10008464: /-- c709 beqz a4,1000846e <udiv64_slow+0xa4>
/proc/self/cwd/sw/device/lib/base/math.c:41
10008466: | 00772023 sw t2,0(a4)
1000846a: | 01c72223 sw t3,4(a4)
/proc/self/cwd/sw/device/lib/base/math.c:43
1000846e: \-> 8546 mv a0,a7
10008470: 85c2 mv a1,a6
10008472: 4432 lw s0,12(sp)
10008474: 0141 addi sp,sp,16
10008476: 8082 ret
10008478: c0001073 unimp
1000847c: c0001073 unimpAfter (with minsize, and manual implementation of __lshrdi3 marked as noinline):
10008350 <udiv64_slow>:
udiv64_slow():
/proc/self/cwd/sw/device/lib/base/math.c:56
10008350: 7179 addi sp,sp,-48
10008352: d606 sw ra,44(sp)
10008354: d422 sw s0,40(sp)
10008356: d226 sw s1,36(sp)
10008358: d04a sw s2,32(sp)
1000835a: ce4e sw s3,28(sp)
1000835c: cc52 sw s4,24(sp)
1000835e: ca56 sw s5,20(sp)
10008360: c85a sw s6,16(sp)
10008362: c65e sw s7,12(sp)
10008364: c462 sw s8,8(sp)
10008366: c266 sw s9,4(sp)
10008368: c06a sw s10,0(sp)
1000836a: 893a mv s2,a4
1000836c: 8bb6 mv s7,a3
1000836e: 8ab2 mv s5,a2
10008370: 89ae mv s3,a1
10008372: 8a2a mv s4,a0
10008374: 4501 li a0,0
10008376: 4581 li a1,0
10008378: 4c81 li s9,0
1000837a: 4b01 li s6,0
1000837c: 03f00d13 li s10,63
10008380: 5c7d li s8,-1
/proc/self/cwd/sw/device/lib/base/math.c:67
10008382: /----------- 078d0563 beq s10,s8,100083ec <udiv64_slow+0x9c>
/proc/self/cwd/sw/device/lib/base/math.c:68
10008386: | /-------> 01f55613 srli a2,a0,0x1f
1000838a: | | 0586 slli a1,a1,0x1
1000838c: | | 00c5e4b3 or s1,a1,a2
10008390: | | 00151413 slli s0,a0,0x1
/proc/self/cwd/sw/device/lib/base/math.c:70
10008394: | | 8552 mv a0,s4
10008396: | | 85ce mv a1,s3
10008398: | | 866a mv a2,s10
1000839a: | | 3741 jal 1000831a <__lshrdi3>
1000839c: | | 8905 andi a0,a0,1
1000839e: | | 008565b3 or a1,a0,s0
/proc/self/cwd/sw/device/lib/base/math.c:76
100083a2: | | /----- 01748963 beq s1,s7,100083b4 <udiv64_slow+0x64>
100083a6: | | | 0174b533 sltu a0,s1,s7
100083aa: | | | /-- a039 j 100083b8 <udiv64_slow+0x68>
100083ac: | | | | c0001073 unimp
100083b0: | | | | c0001073 unimp
100083b4: | | \--|-> 0155b533 sltu a0,a1,s5
100083b8: | | \-> 00154613 xori a2,a0,1
100083bc: | | 01fcd513 srli a0,s9,0x1f
100083c0: | | 0b06 slli s6,s6,0x1
100083c2: | | 00ab6b33 or s6,s6,a0
100083c6: | | 0c86 slli s9,s9,0x1
100083c8: | | 40c00533 neg a0,a2
100083cc: | | 017576b3 and a3,a0,s7
100083d0: | | 01557733 and a4,a0,s5
100083d4: | | 40e58533 sub a0,a1,a4
100083d8: | | 00e5b5b3 sltu a1,a1,a4
100083dc: | | 8c95 sub s1,s1,a3
100083de: | | 40b485b3 sub a1,s1,a1
100083e2: | | 00ccecb3 or s9,s9,a2
/proc/self/cwd/sw/device/lib/base/math.c:67
100083e6: | | 1d7d addi s10,s10,-1
100083e8: | \-------- f98d1fe3 bne s10,s8,10008386 <udiv64_slow+0x36>
/proc/self/cwd/sw/device/lib/base/math.c:82
100083ec: \--------/-X 00090563 beqz s2,100083f6 <udiv64_slow+0xa6>
/proc/self/cwd/sw/device/lib/base/math.c:83
100083f0: | 864a mv a2,s2
100083f2: | c208 sw a0,0(a2)
100083f4: | c24c sw a1,4(a2)
/proc/self/cwd/sw/device/lib/base/math.c:85
100083f6: \-> 8566 mv a0,s9
100083f8: 85da mv a1,s6
100083fa: 50b2 lw ra,44(sp)
100083fc: 5422 lw s0,40(sp)
100083fe: 5492 lw s1,36(sp)
10008400: 5902 lw s2,32(sp)
10008402: 49f2 lw s3,28(sp)
10008404: 4a62 lw s4,24(sp)
10008406: 4ad2 lw s5,20(sp)
10008408: 4b42 lw s6,16(sp)
1000840a: 4bb2 lw s7,12(sp)
1000840c: 4c22 lw s8,8(sp)
1000840e: 4c92 lw s9,4(sp)
10008410: 4d02 lw s10,0(sp)
10008412: 6145 addi sp,sp,48
10008414: 8082 ret
10008416: c0001073 unimp
1000841a: c0001073 unimp