hexChars: dw 0, 0x03ff0000, 0x0000007e, 0x0000007e, 0, 0, 0, 0
# hexChars[ch >> 5] & (1 << (ch & 0x1F))
srl t0, a0, 5 # ch >> 5
lw t0, hexChars(t0) #
andi t1, a0, 0x1F # ch & 0x1F
addi t2, zero, 1 # 1
sll t2, a0, t1 # 1 << (ch & 0x1F)
and t0, t0, t2 # t0 is 0 if not a hex char
aGV4Q2hhcnM6IGR3IDAsIDB4MDNmZjAwMDAsIDB4MDAwMDAwN2UsIDB4MDAwMDAwN2UsIDAsIDAsIDAsIDAKCiMgaGV4Q2hhcnNbY2ggPj4gNV0gJiAoMSA8PCAoY2ggJiAweDFGKSkKCnNybCB0MCwgYTAsIDUJCSMgY2ggPj4gNQpsdyB0MCwgaGV4Q2hhcnModDApCSMKYW5kaSB0MSwgYTAsIDB4MUYJIyBjaCAmIDB4MUYKYWRkaSB0MiwgemVybywgMQkjIDEKc2xsIHQyLCBhMCwgdDEJCSMgMSA8PCAoY2ggJiAweDFGKQphbmQgdDAsIHQwLCB0MgkJIyB0MCBpcyAwIGlmIG5vdCBhIGhleCBjaGFyCg==